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19 pages, 3421 KiB  
Article
Dried Apricot Polyphenols Suppress the Growth of A549 Human Lung Adenocarcinoma Cells by Inducing Apoptosis via a Mitochondrial-Dependent Pathway
by Caiyun Zhao, Jingteng Wang, Jintian Guo, Wenjing Gao, Bin Li, Xin Shang, Li Zheng, Bin Wu and Yinghua Fu
Foods 2025, 14(1), 108; https://doi.org/10.3390/foods14010108 (registering DOI) - 2 Jan 2025
Viewed by 245
Abstract
Dried apricots are rich in a variety of polyphenols, which have anti-cancer activity. In this study, 949 phenolic substances were found by means of UPLC-MS/MS, mainly including 2′,7-dihydroxy-3′,4′-dimethoxyisoflavan, scopoletin, rutin, quercetin-3-O-robinobioside, and elaidolinolenic acid. The results indicated that dried apricot polyphenols (DAPs) could [...] Read more.
Dried apricots are rich in a variety of polyphenols, which have anti-cancer activity. In this study, 949 phenolic substances were found by means of UPLC-MS/MS, mainly including 2′,7-dihydroxy-3′,4′-dimethoxyisoflavan, scopoletin, rutin, quercetin-3-O-robinobioside, and elaidolinolenic acid. The results indicated that dried apricot polyphenols (DAPs) could cause cell cycle arrest in the G0/G1 and G2/M phases by decreasing the cyclin D1, CDK4, cyclin B1, CDK1, and CDK6 levels in A549 human lung adenocarcinoma cells. Moreover, the ROS and Bax levels were increased, and the Bcl-2 and mitochondrial membrane potential were decreased in A549 cells treated with DAP, increasing caspase-9, caspase-3, and cleaved-PARP1 activities and leading to apoptosis of the A549 cells. Meanwhile, tumor growth was also inhibited by DAPs in an A549 tumor-bearing mouse model, Bax and caspase-3 were upregulated, and Bcl-2 was downregulated, inducing apoptosis of lung cancer cells. In conclusion, DAPs could inhibit lung cancer cell growth by inducing apoptosis due to cell cycle arrest and mitochondria-dependent pathways. Full article
(This article belongs to the Section Food Nutrition)
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Figure 1

Figure 1
<p>Flowchart of the animal experiment design.</p>
Full article ">Figure 2
<p>Effect of DAPs on A549 cell activity. (<b>A</b>) Cell viability assessed with CCK-8 assay; (<b>B</b>) cell morphology observed under inverted microscope, scale bar: 100μm. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, **** <span class="html-italic">p</span> &lt; 0.0001 compared to the control group.</p>
Full article ">Figure 2 Cont.
<p>Effect of DAPs on A549 cell activity. (<b>A</b>) Cell viability assessed with CCK-8 assay; (<b>B</b>) cell morphology observed under inverted microscope, scale bar: 100μm. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, **** <span class="html-italic">p</span> &lt; 0.0001 compared to the control group.</p>
Full article ">Figure 3
<p>Effect of DAPs on A549 cell migration. (<b>A</b>) Migration of A549 cells observed with inverted microscope, scale bar: 100 μm; (<b>B</b>) analysis of A549 cell migration using Image J. *** <span class="html-italic">p</span> &lt; 0.001, **** <span class="html-italic">p</span> &lt; 0.0001 compared to the control group.</p>
Full article ">Figure 4
<p>Effect of DAPs on apoptosis in A549 cells. (<b>A</b>) Apoptosis rate analyzed via flow cytometry; (<b>B</b>) nuclear morphology observed under fluorescence microscope, scale bar: 100 μm; (<b>C</b>) Bax; (<b>D</b>) Bcl-2. *** <span class="html-italic">p</span> &lt; 0.001, **** <span class="html-italic">p</span> &lt; 0.0001 compared to the control group.</p>
Full article ">Figure 4 Cont.
<p>Effect of DAPs on apoptosis in A549 cells. (<b>A</b>) Apoptosis rate analyzed via flow cytometry; (<b>B</b>) nuclear morphology observed under fluorescence microscope, scale bar: 100 μm; (<b>C</b>) Bax; (<b>D</b>) Bcl-2. *** <span class="html-italic">p</span> &lt; 0.001, **** <span class="html-italic">p</span> &lt; 0.0001 compared to the control group.</p>
Full article ">Figure 5
<p>Effect of DAPs on the A549 cell cycle. (<b>A</b>) The cell cycle distribution was detected via flow cytometry; (<b>B</b>) cyclin D1; (<b>C</b>) CDK4; (<b>D</b>) CDK6; (<b>E</b>) cyclin B; (<b>F</b>) CDK1. ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, **** <span class="html-italic">p</span> &lt; 0.0001 compared to the control group.</p>
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<p>Effect of DAPs on the MMP of A549 cells. (<b>A</b>) The MMP observed under fluorescence microscope, scale bar: 100 μm; (<b>B</b>) caspase-9; (<b>C</b>) caspase-3; (<b>D</b>) cleaved-PARP1/PARP1. * <span class="html-italic">p</span> &lt; 0.05, *** <span class="html-italic">p</span> &lt; 0.001, **** <span class="html-italic">p</span> &lt; 0.0001 compared to the control group.</p>
Full article ">Figure 7
<p>Effect of DAPs on ROS in A549 cells. (<b>A</b>) Fluorescence intensity of ROS assessed using fluorescence microscopy, scale bar: 100 μm; (<b>B</b>) the cellular ROS level quantified via flow cytometry. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, **** <span class="html-italic">p</span> &lt; 0.0001 compared to the control group; ## <span class="html-italic">p</span> &lt; 0.01, #### <span class="html-italic">p</span> &lt; 0.0001 compared to the 1000 μg/mL + NAC group.</p>
Full article ">Figure 7 Cont.
<p>Effect of DAPs on ROS in A549 cells. (<b>A</b>) Fluorescence intensity of ROS assessed using fluorescence microscopy, scale bar: 100 μm; (<b>B</b>) the cellular ROS level quantified via flow cytometry. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, **** <span class="html-italic">p</span> &lt; 0.0001 compared to the control group; ## <span class="html-italic">p</span> &lt; 0.01, #### <span class="html-italic">p</span> &lt; 0.0001 compared to the 1000 μg/mL + NAC group.</p>
Full article ">Figure 8
<p>Anti-tumor effects of DAPs in vivo. (<b>A</b>) Variations in the body weight of mice during the experiment; (<b>B</b>) changes in tumor volume during the experiment; (<b>C</b>) tumor weight at the conclusion of the experiment; (<b>D</b>) pathological evaluation of the tumor tissue, scale bar: 200 μm; (<b>E</b>) Ki67 expression in the tumor tissue, scale bar: 100 μm. **** <span class="html-italic">p</span> &lt; 0.0001 compared to the MC group.</p>
Full article ">Figure 9
<p>Effect of DAPs on mouse organs. (<b>A</b>) Hearts; (<b>B</b>) livers; (<b>C</b>) spleens; (<b>D</b>) lungs; (<b>E</b>) kidneys; (<b>F</b>) pathological evaluation of liver and kidney, scale bar: 200 μm; (<b>G</b>) AST; (<b>H</b>) ALT; (<b>I</b>) CR; (<b>J</b>) BUN; triangle, square, bullet represent the distribution of samples in each group; ** <span class="html-italic">p</span> &lt; 0.01 compared to the MC group.</p>
Full article ">Figure 10
<p>Expression of apoptosis-related proteins in tumor tissue. (<b>A</b>) Bax; (<b>B</b>) Bcl-2; (<b>C</b>) caspase-3. **** <span class="html-italic">p</span> &lt; 0.0001 compared to the MC group.</p>
Full article ">
21 pages, 1137 KiB  
Article
CDC20 and CCNB1 Overexpression as Prognostic Markers in Bladder Cancer
by Hatice Sevim Nalkiran, Ilknur Biri, Ihsan Nalkiran, Hakki Uzun, Sumeyye Durur and Recep Bedir
Diagnostics 2025, 15(1), 59; https://doi.org/10.3390/diagnostics15010059 - 29 Dec 2024
Viewed by 315
Abstract
Background: Bladder cancer (BC) is one of the ten most common cancers worldwide, with a high recurrence rate and significant variation in clinical outcomes based on tumor grade and stage. This study aimed to investigate the gene expression profiles at different cancer stages [...] Read more.
Background: Bladder cancer (BC) is one of the ten most common cancers worldwide, with a high recurrence rate and significant variation in clinical outcomes based on tumor grade and stage. This study aimed to investigate the gene expression profiles at different cancer stages to assess their potential prognostic value. Methods: RNA was extracted from paraffin-embedded BC tissues and the gene expression levels of CDC20 and CCNB1 were analyzed using qRT-PCR. A total of 54 BC patient samples were included in the analysis and categorized into low-grade (LG) (n = 23) and high-grade (HG) (n = 31) tumors, as well as stages pTa, pT1, and pT2. Results: CDC20 gene expression was significantly higher in the HG group (mean fold-change: 16.1) compared to the LG group (mean fold-change: 10.54), indicating a significant association with tumor grade (p = 0.039). However, no significant differences were observed in CDC20 expression across the cancer stages. For CCNB1, while gene expression was significantly elevated in higher-stage tumors (pT2 vs. pTa; p = 0.038), no significant association was found between CCNB1 expression and tumor grade. Survival analysis revealed that increased CCNB1 expression and advanced cancer stage were associated with poorer overall survival, whereas no significant impact of CDC20 expression or tumor grade on survival was observed. Correlation analysis indicated a positive relationship between CDC20 expression and tumor grade (r = 0.284, p = 0.038) and between CCNB1 expression and tumor stage (r = 0.301, p = 0.027). Conclusions: Our findings suggest that CDC20 overexpression is linked to higher tumor grades, while CCNB1 overexpression is associated with more advanced cancer stages in BC. These results underscore the potential utility of CDC20 and CCNB1 as biomarkers for tumor prognosis and as therapeutic targets. Further studies with larger cohorts are needed to validate these findings and better understand the molecular mechanisms driving BC progression. Full article
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Figure 1

Figure 1
<p>Differential expression of CDC20 and CCNB1 genes in BC tissues across different grades and stages. (<b>a</b>) CDC20 gene expression fold-change comparison between LG and HG BC tissues. (<b>b</b>) CCNB1 gene expression (fold-change) comparison between LG and HG BC tissues. (<b>c</b>) CDC20 gene expression fold-change in BC tissues across pathological stages (pTa, pT1, and pT2). (<b>d</b>) CCNB1 gene expression fold-change in BC tissues across pathological stages (pTa, pT1, and pT2). (<b>e</b>) Heatmap visualization of CDC20 and CCNB1 gene expression levels in BC tissues categorized by grade (LG and HG) and stage (pTa, pT1, and pT2). Red indicates higher expression and green indicates lower expression levels. LG: low-grade tumor, HG: high-grade tumor. The median value is indicated by a bold black line.</p>
Full article ">Figure 2
<p>Kaplan−Meier survival curves for tumor grades and cancer stages (<b>a</b>) CDC20 expression: Survival comparison between patients with downregulated and upregulated CDC20 expression, showing no significant difference (log-rank <span class="html-italic">p</span> = 0.450). (<b>b</b>) CCNB1 expression: Patients with upregulated CCNB1 expression exhibit significantly worse overall survival compared to those with downregulated expression (log-rank <span class="html-italic">p</span> = 0.047). (<b>c</b>) Tumor grade (LG vs. HG): No significant difference in survival is observed between LG and HG tumors (log-rank <span class="html-italic">p</span> = 0.891). (<b>d</b>) Tumor stage (pTa, pT1, and pT2): Significant survival differences are evident across tumor stages, with more advanced stages (pT2) associated with poorer survival outcomes (log-rank <span class="html-italic">p</span> = 0.026).</p>
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18 pages, 4915 KiB  
Article
Novel 4-alkoxy Meriolin Congeners Potently Induce Apoptosis in Leukemia and Lymphoma Cells
by Karina S. Krings, Tobias R. Wassenberg, Pablo Cea-Medina, Laura Schmitt, Ilka Lechtenberg, Tanya R. Llewellyn, Nan Qin, Holger Gohlke, Sebastian Wesselborg and Thomas J. J. Müller
Molecules 2024, 29(24), 6050; https://doi.org/10.3390/molecules29246050 - 23 Dec 2024
Viewed by 454
Abstract
Meriolins (3-(pyrimidin-4-yl)-7-azaindoles) are synthetic hybrids of the naturally occurring alkaloids variolin and meridianin and display a strong cytotoxic potential. We have recently shown that the novel derivative meriolin 16 is highly cytotoxic in several lymphoma and leukemia cell lines as well as [...] Read more.
Meriolins (3-(pyrimidin-4-yl)-7-azaindoles) are synthetic hybrids of the naturally occurring alkaloids variolin and meridianin and display a strong cytotoxic potential. We have recently shown that the novel derivative meriolin 16 is highly cytotoxic in several lymphoma and leukemia cell lines as well as in primary patient-derived lymphoma and leukemia cells and predominantly targets cyclin-dependent kinases (CDKs). Here, we efficiently synthesized nine novel 2-aminopyridyl meriolin congeners (3a3i), i.e., pyrimeriolins, using a one-pot Masuda borylation-Suzuki coupling (MBSC) sequence, with eight of them bearing lipophilic alkoxy substituents of varying length, to systematically determine the influence of the alkoxy sidechain length on the biological activity. All the synthesized derivatives displayed a pronounced cytotoxic potential, with six compounds showing IC50 values in the nanomolar range. Derivatives 3b3f strongly induced apoptosis and activated caspases with rapid kinetics within 3–4 h in Jurkat leukemia and Ramos lymphoma cells. The induction of apoptosis by the most potent derivative 3e was mediated by the intrinsic mitochondrial death pathway, as it was blocked in caspase-9 deficient and Apaf-1 knockdown Jurkat cells. However, as recently shown for meriolin 16, derivative 3e was able to induce apoptosis in the Jurkat cells overexpressing the antiapoptotic protein Bcl-2. Since tumor cells often inactivate the intrinsic mitochondrial apoptosis pathway (e.g., by overexpression of Bcl-2), these meriolin congeners represent promising therapeutic agents for overcoming therapeutic resistance. Full article
(This article belongs to the Special Issue Synthesis, Characterization, and Biological Evaluation of Alkaloids)
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Graphical abstract

Graphical abstract
Full article ">Figure 1
<p><span class="html-italic">Meridianin A</span> and <span class="html-italic">variolin B</span> alongside the semi-synthetic hybrid structure of the <span class="html-italic">meriolins</span> [<a href="#B10-molecules-29-06050" class="html-bibr">10</a>].</p>
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<p>Synthesized <span class="html-italic">pyrimeriolins</span> <b>3</b> via the MBSC-sequence (yields are given in parenthesis).</p>
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<p>Reference substances for the assays (synthesized according to our previous protocol) [<a href="#B35-molecules-29-06050" class="html-bibr">35</a>].</p>
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<p>The synthesized <span class="html-italic">pyrimeriolin</span> derivatives show prominent cytotoxicity in human Burkitt lymphoma (Ramos) cells and T-cell acute leukemia (Jurkat) cell lines. Ramos and Jurkat cells were incubated for 24 h with increasing concentrations of <span class="html-italic">meriolin</span> <b>3</b> and <b>16</b> and the newly synthesized <span class="html-italic">pyrimeriolins</span> <b>3a</b>–<b>3i</b>. The cell viability was determined with the resazurin reduction assay (AlamarBlue<sup>®</sup> assay). Data points shown represent the mean (±SD) of three independent experiments. The respective values were normalized to the DMSO control (0.1% <span class="html-italic">v</span>/<span class="html-italic">v</span>) so that the control was set to 100%. Non-linear regression curve fitting was used to calculate IC<sub>50</sub> (IC<sub>50</sub> = half maximum inhibitory concentration) values using Prism 6 (GraphPad software).</p>
Full article ">Figure 5
<p>Binding of <span class="html-italic">pyrimeriolin</span> <b>3e</b> and <b>3i</b> to CDK9. Left panels show a general view of the 10 best binding poses of compounds <b>3e</b> (<b>A</b>) and <b>3i</b> (<b>B</b>) placed in the active site of CDK9. The right panels show slices through the binding site. The sidechains of the binding site amino acids are depicted as white sticks, whereas the best 10 scored binding poses for <span class="html-italic">pyrimeriolins</span> <b>3e</b> and <b>3i</b> are shown as yellow sticks.</p>
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<p>Molecular dynamics simulations starting from the binding poses of <span class="html-italic">meriolin</span> <b>3e</b> and <b>3i</b> in CDK9. (<b>A</b>) Histogram of the non-fitted RMSD obtained for the full <span class="html-italic">pyrimeriolin</span> <b>3e</b> ligand (yellow) or only its 7-azaindolyl moiety (blue). (<b>B</b>) Active site of CDK9 (shown as gray cartoon) showing the effective volume occupied by <span class="html-italic">pyrimeriolin</span> <b>3e</b> (red grid), the binding pose of the ligand in the last simulation frame is shown as yellow sticks. (<b>C</b>) Same as in (<b>A</b>) but for <b>3i</b>. (<b>D</b>) Same as in (<b>B</b>) but for <b>3i</b>.</p>
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<p>Apoptosis-induced DNA fragmentation by the (<span class="html-italic">pyri</span>)<span class="html-italic">meriolin</span> derivatives. Ramos or Jurkat cells were treated with 0.1 µM or 1.0 µM of the respective <span class="html-italic">(pyri)meriolin</span> derivatives, 0.1% <span class="html-italic">v</span>/<span class="html-italic">v</span> DMSO (diluent control), or 2.5 µM staurosporine (STS; as a positive control for apoptosis induction) for 24 h. Apoptosis-induced DNA degradation was measured via flow-cytometric measurement of propidium iodide stained apoptotic hypodiploid nuclei [<a href="#B41-molecules-29-06050" class="html-bibr">41</a>]. The experiment was performed in triplicates (error bars = mean ± SD).</p>
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<p>Compounds <b>3b</b>–<b>3f</b> induce caspase activation in rapid kinetics in Ramos cells. Ramos cells were treated with 0.1 µM or 1.0 µM of the respective <span class="html-italic">(pyri)meriolin</span> derivatives for up to 8 h. As a positive control, the potent apoptotic stimulus staurosporine (2.5 µM; STS) was included in each kinetic. Subsequently, caspase-3 activity was determined by measurement of the fluorescence of the profluorescent caspase-3 substrate DEVD-AMC in a spectrofluorometer. Error bars represent the mean ± SD of one experiment performed in triplicates.</p>
Full article ">Figure 9
<p>Compounds <b>3b</b>–<b>3f</b> induce the cleavage of the caspase substrate PARP in rapid kinetics in Ramos cells. 1 × 10<sup>6</sup> Ramos cells were treated with 1 µM of the respective <span class="html-italic">(pyri)meriolin</span> derivatives for 2, 4, 6 and 8 h. In addition, the cells were treated for 8 h with DMSO (0.1% <span class="html-italic">v</span>/<span class="html-italic">v</span>) as a diluent control or for 8 h with 2.5 µM staurosporine. The resulting cells were prepared for immunoblot analysis and antibodies of caspase-3 substrate PARP were used to visualize the cleavage of this substrate. The cleavage of the caspase substrate PARP was detected by immunoblotting. Solid arrowheads indicate the uncleaved form of PARP (p116); open arrowheads indicate the cleaved form (p85). Immunoblotting for glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was used as loading control.</p>
Full article ">Figure 10
<p><span class="html-italic">Meriolin</span> derivate <b>3e</b> activates the mitochondrial apoptosis pathway in Bcl-2 overexpressing Jurkat cells. (<b>A</b>) <b>3e</b>-induced apoptosis requires Apaf-1. The CRISPR inhibition system was used to achieve a stable knockdown of Apaf-1 [<a href="#B35-molecules-29-06050" class="html-bibr">35</a>]. Apaf-1 proficient (Jurkat-Apaf1-pos.; black squares) and Apaf-1 knockdown Jurkat cells (Jurkat-Apaf1-knockdown; white squares) were treated with increasing concentrations of compound <b>3e</b>. After 24 h, apoptosis was assessed by the flow cytometric measurement of apoptotic hypodiploid nuclei. (<b>B</b>) <b>3e</b>-induced apoptosis requires caspase-9. Caspase-9-proficient Jurkat cells (Jurkat Casp9-pos., black squares) or caspase-9-deficient Jurkat cells (Jurkat Casp9-neg., white squares) [<a href="#B45-molecules-29-06050" class="html-bibr">45</a>] were treated with increasing concentrations of compound <b>3e</b>. After 24 h, apoptosis was assessed by the flow cytometric measurement of apoptotic hypodiploid nuclei. (<b>C</b>) <b>3e</b> induces apoptosis in the presence of antiapoptotic Bcl-2. Jurkat cells stably transfected with vectors encoding Bcl-2 (Jurkat Bcl-2; white squares) [<a href="#B46-molecules-29-06050" class="html-bibr">46</a>] or empty vector (Jurkat vector; black squares) were treated with increasing concentrations of compound <b>3e</b>. After 24 h, apoptosis was assessed by the flow cytometric measurement of apoptotic hypodiploid nuclei. (<b>D</b>) The induction of apoptosis by the DNA-damaging anticancer drug etoposide (used as a control for the activation of the mitochondrial apoptosis pathway) was blocked in caspase-9 deficient and Apaf-1 knockdown Jurkat cells, as well as in Bcl-2 overexpressing Jurkat. Apaf-1 proficient (Jurkat-Apaf1-pos.) or Apaf-1 knockdown Jurkat cells (Jurkat-Apaf1-knockdown), caspase-9 proficient Jurkat cells (Jurkat Casp9-pos.) or caspase-9 deficient (Jurkat Casp9-neg.) Jurkat cells or Jurkat cells overexpressing Bcl-2 (Jurkat Bcl-2) or empty vector (Jurkat vector) were treated with 50 µM etoposide or 0.1% <span class="html-italic">v</span>/<span class="html-italic">v</span> DMSO (diluent control). After 24 h, apoptosis was assessed by flow cytometric measurement of the apoptotic hypodiploid nuclei. (<b>E</b>) Ramos and Jurkat cells were incubated with <span class="html-italic">pyrimeriolin</span> derivative <b>3e</b> (0.1, 1.0 or 10 µM) or DMSO (0.1% <span class="html-italic">v</span>/<span class="html-italic">v</span>) as a diluent control for 6 h. Treatment with 0.1 or 1.0 µM of the CDK9-specific inhibitor AZD4573 [<a href="#B47-molecules-29-06050" class="html-bibr">47</a>] served as positive control. Inhibition of CDK9-mediated phosphorylation of RNA polymerase II at Ser2 (p-Ser2 of RNA pol II) was monitored by immunoblotting. Vinculin served as a loading control.</p>
Full article ">Scheme 1
<p>Schematic synthesis of <span class="html-italic">meriolins</span> via one-pot MBSC-sequence [<a href="#B10-molecules-29-06050" class="html-bibr">10</a>,<a href="#B29-molecules-29-06050" class="html-bibr">29</a>,<a href="#B30-molecules-29-06050" class="html-bibr">30</a>].</p>
Full article ">Scheme 2
<p>Retrosynthetic breakdown of the alkoxy substituted <span class="html-italic">pyrimeriolins</span> <b>3</b> [<a href="#B10-molecules-29-06050" class="html-bibr">10</a>,<a href="#B14-molecules-29-06050" class="html-bibr">14</a>].</p>
Full article ">Scheme 3
<p>MBSC-sequence conditions for the synthesis of <span class="html-italic">pyrimeriolins</span> <b>3</b> [<a href="#B10-molecules-29-06050" class="html-bibr">10</a>].</p>
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15 pages, 15559 KiB  
Article
The Role of Flavonoids from Aurantii Fructus Immaturus in the Alleviation of Allergic Asthma: Theoretical and Practical Insights
by Jingwen Xue, Yuntong Liu, Qiushi Chen, Huimin Liu, Huijing Zhang, Bo Wang, Yongri Jin, Xuwen Li and Xiaolei Shi
Int. J. Mol. Sci. 2024, 25(24), 13587; https://doi.org/10.3390/ijms252413587 - 19 Dec 2024
Viewed by 348
Abstract
Flavonoids derived from plants in the citrus family can have an alleviating effect on allergic asthma. The aim of this study was to provide insights into the mechanisms by which these compounds exert their effects on allergic asthma by combining theoretical and practical [...] Read more.
Flavonoids derived from plants in the citrus family can have an alleviating effect on allergic asthma. The aim of this study was to provide insights into the mechanisms by which these compounds exert their effects on allergic asthma by combining theoretical and practical approaches. Aurantii Fructus Immaturus flavonoids (AFIFs) were obtained by solvent extraction and were determined by high performance liquid chromatography (HPLC). In vivo and in vitro experiments combined with network pharmacology, Mendelian randomization (MR) analysis and the AutoDock method were applied to study the mechanism of their effects. The main AFIFs were found to be hesperidin (13.21 mg/g), neohesperidin (287.26 mg/g), naringin (322.56 mg/g), and narirutin (19.35 mg/g). Based on the network pharmacology and MR analysis results, five targets Caspase 3 (CASP3), CyclinD1 (CCND1), Intercellular adhesion molecule (ICAM), erb-b2 receptor tyrosine kinase 2 (ERBB2), and rubisco accumulation factor 1 (RAF1) were selected, and the interactions between the AFIFs and the targets were studied using AutoDock Vina. The results indicated that glycosidic bonds play an important role in the interactions between AFIFs and both ERBB2 and RAF1. Full article
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Figure 1

Figure 1
<p>HPLC analysis of AFIFs and effects of AFIFs on body weights, rectal temperature, spleen, thymus index and inflammatory response in vivo. (<b>A</b>) HPLC of AFIFs; (<b>B</b>) Structures of hesperidin, neohesperidin, naringin, and narirutin. Red circle presents the different connection of glycosidic bonds; Blue circle presents the different connection of -OH and -OCH<sub>3</sub>; (<b>C</b>) Effects of AFIFs on body weight changes; (<b>D</b>) Effects of AFIFs on rectal temperature change; (<b>E</b>) Effects of AFIFs on thymus index; (<b>F</b>) Effects of AFIFs on spleen index; (<b>G</b>) Effects of AFIFs on total IgE; (<b>H</b>) Effects of AFIFs on IL-17A in BALF; (<b>I</b>) Effects of AFIFs on IL-13 in BALF. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, compared with the Control group; # <span class="html-italic">p</span> &lt; 0.05, ## <span class="html-italic">p</span> &lt; 0.01, compared with the Model group.</p>
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<p>(<b>A</b>) Histomorphological changes in the lungs of mice (Control); (<b>B</b>) Histomorphological changes in the lungs of mice (Model); (<b>C</b>) Histomorphological changes in the lungs of mice (AFIFs dose 10 mg/kg); (<b>D</b>) Histomorphological changes in the lungs of mice (AFIFs dose 50 mg/kg); (<b>E</b>) Histomorphological changes in the lungs of mice (AFIFs dose 100 mg/kg).</p>
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<p>Effects of AFIFs on mast cell degranulation. (<b>A</b>) Effects of AFIFs on cell viability; (<b>B</b>) Effects of AFIFs on β-HEX; (<b>C</b>) Effects of AFIFs on Ca<sup>2+</sup> influx; (<b>D</b>) Effects of AFIFs on IL-4 release; (<b>E</b>) Effects of AFIFs on histamine release. * <span class="html-italic">p</span> &lt; 0.05,** <span class="html-italic">p</span> &lt; 0.01, compared with the Control group; # <span class="html-italic">p</span> &lt; 0.05, ## <span class="html-italic">p</span> &lt; 0.01, compared with the Model group (0 μg/mL).</p>
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<p>Network pharmacology of AFIFs and allergic asthma. (<b>A</b>) The number of allergic asthma-related targets and AFIFs targets showed by Venn; (<b>B</b>) Network of 22 targets; (<b>C</b>) KEGG analysis; (<b>D</b>) GO-CC analysis; (<b>E</b>) GO-MF analysis; (<b>F</b>) GO-BP analysis.</p>
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<p>MR association between expression of gene <span class="html-italic">BAX</span>, <span class="html-italic">CASP3</span>, <span class="html-italic">CCND1</span>, <span class="html-italic">ERBB2</span>, <span class="html-italic">ICAM1</span>, <span class="html-italic">PEBP1</span>, <span class="html-italic">RAF1</span>, and allergic asthma outcomes. Red pots indicated Odds ratio &gt; 1, Green pots indicated Odds ratio &lt; 1.</p>
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<p>Molecular docking between key protein and AFIFs; color balls indicated amino acid residues of different targets. (<b>I</b>) interaction between hesperidin and key protein; (<b>II</b>) interaction between neohesperidin and key protein; (<b>III</b>) interaction between naringin and key protein; (<b>IV</b>) interaction between narirutin and key protein.</p>
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17 pages, 1305 KiB  
Article
CT-Scan-Assessed Body Composition and Its Association with Tumor Protein Expression in Endometrial Cancer: The Role of Muscle and Adiposity Quantities
by Cuthbert Mario Mahenge, Rand Talal Akasheh, Ben Kinder, Xuan Viet Nguyen, Faiza Kalam and Ting-Yuan David Cheng
Cancers 2024, 16(24), 4222; https://doi.org/10.3390/cancers16244222 - 18 Dec 2024
Viewed by 402
Abstract
Background: Endometrial cancer is strongly associated with obesity, and tumors often harbor mutations in major cancer signaling pathways. To inform the integration of body composition into targeted therapy paradigms, this hypothesis-generating study explores the association between muscle mass, body fat, and tumor [...] Read more.
Background: Endometrial cancer is strongly associated with obesity, and tumors often harbor mutations in major cancer signaling pathways. To inform the integration of body composition into targeted therapy paradigms, this hypothesis-generating study explores the association between muscle mass, body fat, and tumor proteomics. Methods: We analyzed data from 113 patients in The Cancer Genome Atlas (TCGA) and Cancer Proteomic Tumor Analysis Consortium (CPTAC) cohorts and their corresponding abdominal CT scans. Among these patients, tumor proteomics data were available for 45 patients, and 133 proteins were analyzed. Adiposity and muscle components were assessed at the L3 vertebral level on the CT scans. Patients were stratified into tertiles of muscle and fat mass and categorized into three groups: high muscle/low adiposity, high muscle/high adiposity, and low muscle/all adiposities. Linear and Cox regression models were adjusted for study cohort, stage, histology type, age, race, and ethnicity. Results: Compared with the high-muscle/low-adiposity group, both the high-muscle/high-adiposity (HR = 4.3, 95% CI = 1.0–29.0) and low-muscle (HR = 4.4, 95% CI = 1.3–14.9) groups experienced higher mortality. Low muscle was associated with higher expression of phospho-4EBP1(T37 and S65), phospho-GYS(S641) and phospho-MAPK(T202/Y204) but lower expression of ARID1A, CHK2, SYK, LCK, EEF2, CYCLIN B1, and FOXO3A. High muscle/high adiposity was associated with higher expression of phospho-4EBP1 (T37), phospho-GYS (S641), CHK1, PEA15, SMAD3, BAX, DJ1, GYS, PKM2, COMPLEX II Subunit 30, and phospho-P70S6K (T389) but with lower expression of CHK2, CRAF, MSH6, TUBERIN, PR, ERK2, beta-CATENIN, AKT, and S6. Conclusions: These findings demonstrate an association between body composition and proteins involved in key cancer signaling pathways, notably the PI3K/AKT/MTOR, MAPK/ERK, cell cycle regulation, DNA damage response, and mismatch repair pathways. These findings warrant further validation and assessment in relation to prognosis and outcomes in these patients. Full article
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<p>Correlation between TSM (<b>A</b>) and TAT (<b>B</b>) with the BMI of the study participants.</p>
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<p>BMI distribution across the body composition groups of the study participants.</p>
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<p>Kaplan–Meier graph exploring the survival trend based on body composition group.</p>
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<p>Volcano plot of differential expression of protein tumors based on body composition groups with high muscle/low adiposity as a referent group.</p>
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22 pages, 7498 KiB  
Article
Recycling of Uridylated mRNAs in Starfish Embryos
by Haruka Yamazaki, Megumi Furuichi, Mikoto Katagiri, Rei Kajitani, Takehiko Itoh and Kazuyoshi Chiba
Biomolecules 2024, 14(12), 1610; https://doi.org/10.3390/biom14121610 - 16 Dec 2024
Viewed by 411
Abstract
In eukaryotes, mRNAs with long poly(A) tails are translationally active, but deadenylation and uridylation of these tails generally cause mRNA degradation. However, the fate of uridylated mRNAs that are not degraded quickly remains obscure. Here, using tail-seq and microinjection of the 3′ region [...] Read more.
In eukaryotes, mRNAs with long poly(A) tails are translationally active, but deadenylation and uridylation of these tails generally cause mRNA degradation. However, the fate of uridylated mRNAs that are not degraded quickly remains obscure. Here, using tail-seq and microinjection of the 3′ region of mRNA, we report that some mRNAs in starfish are re-polyadenylated to be translationally active after deadenylation and uridylation. In oocytes, uridylated maternal cyclin B mRNAs are stable without decay, and they are polyadenylated to be translated after hormonal stimulation to resume meiosis, whereas they are deadenylated and re-uridylated at the blastula stage, followed by decay. Similarly, deadenylated and uridylated maternal ribosomal protein mRNAs, Rps29 and Rpl27a, were stable and inactive after hormonal stimulation, but they had been polyadenylated and active before hormonal stimulation. At the morula stage, uridylated maternal ribosomal protein mRNAs were re-polyadenylated, rendering them translationally active. These results indicate that uridylated mRNAs in starfish exist in a poised state, allowing them to be recycled or decayed. Full article
(This article belongs to the Special Issue Gametogenesis and Gamete Interaction, 2nd Edition)
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<p><span class="html-italic">Cyclin B</span> mRNA uridylation and degradation. (<b>A</b>) Relative mRNA expression levels for <span class="html-italic">cyclin B</span> in starfish oocytes and embryos. Total RNAs were purified at the indicated time and relative quantification of <span class="html-italic">cyclin B</span> mRNA expression was conducted using RT-qPCR (median ± SEM) (<span class="html-italic">n</span> = 3). (<b>B</b>) Experimental scheme for the microinjection of artificially tagged <span class="html-italic">cyclin B</span> mRNA. Tag-labeled <span class="html-italic">cyclin B</span> mRNA was synthesized and injected (red arrowheads) into oocytes at 0.5 h after 1-MA treatment (+1-MA) or into oocytes without the 1-MA treatment (−1-MA). Oocytes (+1-MA) were inseminated before the first polar body formation, and the total RNAs were purified at the indicated time. (<b>C</b>) Tail length measurements for <span class="html-italic">cyclin B</span> mRNA. At the indicated time, the total RNAs were purified, and a TGIRT template-switching reaction was performed (<a href="#app1-biomolecules-14-01610" class="html-app">Supplementary Figure S1B, left panel</a>). RT-PCR was conducted using the 3′ adaptor reverse primer and <span class="html-italic">cyclin B</span>-specific forward primer. The PCR products were then subjected to polyacrylamide gel electrophoresis and visualized using SYBR-Green I staining. The left and right panels show changes in the tail lengths of endogenous <span class="html-italic">cyclin B</span> mRNA and exogenously microinjected <span class="html-italic">cyclin B</span> mRNAs, respectively. (<b>D</b>) Sanger sequencing results of the 3′ terminal region of cDNA from endogenous maternal <span class="html-italic">cyclin B</span> mRNA of oocytes at Pro-I without 1-MA treatment [Endogenous −1-MA], from stimulated oocytes following first polar body formation (1 h after 1-MA treatment) [Endogenous +1-MA 1 h], and from embryos at the blastula stage (12 h after 1-MA treatment) [Endogenous +1-MA 12 h]. The mean number ± SE of uridine residues in the five nucleotides from the 3′ end was 0.0 ± 0.0 for [Endogenous −1-MA], 2.6 ± 0.5 for [Endogenous +1-MA 1 h], and 1.4 ± 0.3 for [Endogenous +1-MA 12 h]. A Tukey HSD test revealed that the mean number in the [Endogenous −1-MA] group was significantly lower than those in the other two groups (<span class="html-italic">p</span> &lt; 0.05). (<b>E</b>) Sequencing results of the 3′ terminal region of exogenous <span class="html-italic">cyclin B</span> mRNA from stimulated oocytes following first polar body formation (1 h after 1-MA treatment) [Exogenous +1-MA] and from embryos at the blastula stage (12 h after 1-MA treatment) [Exogenous −1-MA].</p>
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<p>Deadenylation, uridylation, and non-canonical poly(A) elongation of the mRNA for ribosomal protein <span class="html-italic">Rps29</span>. (<b>A</b>) Relative levels of mRNA expression for the ribosomal protein in starfish oocytes and embryos. Total RNAs were purified at the indicated time and relative quantification of mRNA expression for the ribosomal protein <span class="html-italic">Rps29</span> was performed using RT-qPCR (median ± SEM) (<span class="html-italic">n</span> = 3). (<b>B</b>) Measurement of the <span class="html-italic">Rps29</span> mRNA tail lengths. Oocytes stimulated with 1-MA were inseminated following second polar body formation. At the indicated time before or after 1-MA stimulation, total RNAs were purified, and adaptor ligation was performed (<a href="#app1-biomolecules-14-01610" class="html-app">Supplementary Figure S1B, right panel</a>). RT-PCR was conducted using the 3′ adaptor reverse primer and <span class="html-italic">Rps29</span>-specific forward primer. The PCR products were then subjected to polyacrylamide gel electrophoresis and visualized using SYBR-Green I staining. Similar results were obtained for three animals. (<b>C</b>) Sequencing results of the 3′ terminal region of cDNA of endogenous maternal <span class="html-italic">Rps29</span> mRNA from oocytes at Pro-I without 1-MA treatment [Endogenous −1-MA], stimulated oocytes after the first polar body formation (1.5 h after 1-MA treatment) [Endogenous +1-MA 1.5 h], and embryos at the blastula stage (12 h after 1-MA treatment) [Endogenous +1-MA 12 h]. The mean number ± SE of uridine residues in the five nucleotides from the 3′ end was 0.0 ± 0.0 for [Endogenous −1-MA] (poly(A) length &gt; 40 residues), 1.9 ± 0.5 for [Endogenous +1-MA 1.5 h] and 0.4 ± 0.2 for [Endogenous +1-MA 12 h] (poly(A) length &gt; 40 residues). A Tukey HSD test revealed that the mean number in the [Endogenous −1-MA] group was significantly lower than the [Endogenous +1-MA 1.5 h] group (<span class="html-italic">p</span> &lt; 0.05).</p>
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<p>Targeted TAIL-Seq of <span class="html-italic">Rps29</span> mRNA. (<b>A</b>) Distribution of poly(A) tail lengths of <span class="html-italic">Rps29</span> mRNA from oocytes without 1-MA treatment (−1-MA), with 1-MA treatment for 1.5 h (+1-MA 1.5 h), and with 1-MA treatment followed by insemination to obtain blastulae at 12 h. Relative frequencies (Y-axis, %) were calculated by dividing the number of detected reads that have indicated poly(A) lengths by the total number of reads that have poly(A) tails. Frequencies of poly(A) tail length &gt; 40 nucleotides are plotted on the right side. The number of reads is shown in parentheses. (<b>B</b>) Relative frequencies of the most frequent nucleotide with additional modifications at the 3′ end of the <span class="html-italic">Rps29</span> mRNA. Using each <span class="html-italic">Rps29</span> mRNA read, the most frequent nucleotides, such as U, G, and C, were determined. Relative frequencies (Y-axis, %) were calculated by dividing the number of reads with the most frequent nucleotides by the total number of reads with the indicated lengths of the poly(A) tails. mRNAs with tail lengths of ≤40 nucleotides and &gt;40 nucleotides were compared in the oocytes with or without 1-MA and at the embryonic stages of development. No modification, neither poly(A) tail nor additional modifications, were present at the end of the poly(A) tails. ≥2; two or more nucleotides comprised the most frequent nucleotides in the mRNA. (<b>C</b>) Distribution of the relative frequencies of non-A residues in the <span class="html-italic">Rps29</span> mRNA tails from blastulae and unstimulated oocytes. At the indicated position of the tails, the relative frequencies of the non-A residues (Y-axis, %) were calculated by dividing the number of reads carrying non-A residues by the total number of reads. The distribution of frequencies for the non-A residues is shown at the indicated position in the tails from 5′ to 3′ (left panel) and from 3′ to 5′ (right panel). The numbers of reads are shown in parentheses. (<b>D</b>) Relative frequencies of non-A residues in the non-canonical poly(A) tails of <span class="html-italic">Rps29</span> mRNA. The relative frequencies of the non-A residues (Y-axis, %) were calculated by dividing the number of each non-A residue (G, C, and U) in the tails of all reads by the number of tail lengths for all reads that have indicated lengths of poly(A) tails. mRNAs with tail lengths of ≤40 nucleotides and &gt;40 nucleotides are compared at the blastula stage.</p>
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<p>Deadenylation, uridylation, and non-canonical poly(A) elongation of the mRNA for exogenous ribosomal protein <span class="html-italic">Rps29</span>. (<b>A</b>) Experimental scheme. Tag-labeled <span class="html-italic">Rps29</span> mRNAs carrying long poly(A) tails were injected into oocytes with or without 1-MA treatment. Total RNAs were purified at the indicated times, whereas stimulated oocytes at 1 h and unstimulated oocytes were not inseminated. (<b>B</b>) Measurement of the tail length of endogenous and exogenous <span class="html-italic">Rps29</span> mRNA. RT-PCR was conducted using the 3′ adaptor reverse primer and <span class="html-italic">Rps29</span> mRNA-specific forward primer. The PCR products were subjected to polyacrylamide gel electrophoresis and SYBR-Green I staining. Similar results were obtained for two animals. (<b>C</b>) Sequencing results of exogenous <span class="html-italic">Rps29</span> mRNA from oocytes without 1-MA treatment [−1-MA], oocytes at 1 h after 1-MA treatment [+1-MA 1 h], and embryos at the morula stage (6 h after 1-MA treatment) [+1-MA 6 h]. ‘(30)’ in the sequences indicates ‘AA…AA’ containing 30 nucleotides. (<b>D</b>) Relative frequencies of the most frequent nucleotides in the additional modifications at the 3′ end of exogenous <span class="html-italic">Rps29</span> mRNA. Relative frequencies (Y-axis, %) were calculated by dividing the number of reads carrying the most frequent nucleotides by the total number of reads from oocytes and embryos at the indicated time. No modification, neither poly(A) tail nor additional modifications were present. “≥2”; two or more nucleotides comprised the most frequent nucleotides. (<b>E</b>) Distribution of the relative frequencies of non-A residues in tails of exogenous <span class="html-italic">Rps29</span> mRNA from oocytes and embryos. At the indicated position of the tails, the relative frequencies of the non-A residues (Y-axis, %) were calculated by dividing the number of reads carrying the non-A residues by the total number of reads. The distribution of frequencies of non-A residues is shown at the indicated position in tails from 5′ to 3′ (left panel) and from 3′ to 5′ (right panel). The numbers of reads are shown in parentheses. Yellow, morulae (5 h after 1-MA treatment). Red, blastulae (11 h after 1-MA treatment). Purple, Pro-I oocytes without 1-MA stimulation (2 h after injection). Blue, Pro-I oocytes without 1-MA stimulation (11 h after injection). (<b>F</b>) Relative frequencies of non-A residues in poly(A) tails of exogenous <span class="html-italic">Rps29</span> mRNA. The relative frequencies of the non-A residues (Y-axis, %) were calculated by dividing the number of each non-A residue (G, C, and U) in the tails of all reads by the number of tail lengths of all reads.</p>
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<p>Deadenylation, uridylation, and non-canonical poly(A) elongation of the mRNA for exogenous ribosomal protein ∆ PAS <span class="html-italic">Rps29</span>. (<b>A</b>) Experimental scheme. Tag-labeled wild-type and ∆ PAS <span class="html-italic">Rps29</span> mRNAs were injected into oocytes. At the indicated time, the total RNA was purified. (<b>B</b>) Measurement of the <span class="html-italic">Rps29</span> mRNA tail length. Total RNA was subjected to a TGIRT template-switching reaction. RT-PCR was conducted using the 3′ adaptor reverse primer and Tag-specific forward primer. The PCR products were then subjected to polyacrylamide electrophoresis and visualized using SYBR-Green I staining. The left and right panels show the changes in tail lengths for the exogenous wild-type and ∆ PAS <span class="html-italic">Rps29</span> mRNAs, respectively. Similar results were obtained for two animals. (<b>C</b>) Sequencing results of the 3′ terminal region of exogenous ∆ PAS <span class="html-italic">Rps29</span> mRNA purified from oocytes at Pro-I without 1-MA treatment at 2 h following injection of the mRNA [−1-MA 2 h], stimulated oocytes at 2 h following 1-MA treatment [+1-MA 2 h], and blastulae (11 h after 1-MA treatment) [+1-MA 11 h].</p>
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<p>Translational activities of the non-canonical poly(A) tails. (<b>A</b>) Experimental scheme. Tag(SGK)-labeled 40S <span class="html-italic">Rps29</span> mRNAs with canonical long poly(A) tails, short poly(A) tails, and non-canonical long and short poly(A) tails were synthesized and injected into oocytes without the 1-MA treatment. The table shows the number of A, T, G, and C nucleotides in the tails. (<b>B</b>) Western blotting of oocytes injected with mRNA carrying an <span class="html-italic">SGK</span> and non-canonical poly(A) tails of the 40S <span class="html-italic">Rps29</span> mRNA. At the indicated time after the injection of exogenous mRNA, oocytes were treated with a sample buffer, followed by polyacrylamide gel electrophoresis and Western blotting using an anti-SGK antibody. Arrowheads (endogenous) indicate endogenous SGK in oocytes. Similar results were obtained for 3 animals. (<b>C</b>) Experimental scheme. Reporter luciferase mRNA between the 5′ and 3′ UTR of 40S <span class="html-italic">Rps29</span> with a canonical long poly(A) tail was injected into oocytes with or without the 1-MA treatment. D, E. 1-MA-stimulated oocytes were inseminated after GVBD to start embryonic development and used to determine the reporter activities (<b>D</b>) (mean ± SE) (<span class="html-italic">n</span> = 3) and the length of poly(A) tails (<b>E</b>). To calculate the relative activity of translation, the luciferase activity of the unstimulated oocytes at 3 h after injection of the reporter mRNA was considered to be 100%, and Student’s t-test was used to determine the significance between the results observed after 3 and 11 h (<b>D</b>). Similar results were obtained for two animal models (<b>D</b>,<b>E</b>).</p>
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<p>Summary of the findings and proposed model. (<b>A</b>) Maternal mRNA deadenylation, uridylation, and non-canonical poly(A) elongation in starfish oocytes and embryos. Upper panel: Before hormonal stimulation of 1-MA, oocytes at Pro-I contain maternal ribosomal protein mRNAs (<span class="html-italic">Rps29</span> and <span class="html-italic">Rpl27a</span>) carrying long poly(A) tails and <span class="html-italic">cyclin B</span> mRNAs with uridylated short poly(A) tails. Following the resumption of meiosis of oocytes undergoing nuclear division of germinal vesicle breakdown, long poly(A) tails of ribosomal protein mRNAs are deadenylated and uridylated (newly added nucleotides are shown in larger font size). Some uridine residues of <span class="html-italic">cyclin B</span> mRNA are trimmed [<a href="#B26-biomolecules-14-01610" class="html-bibr">26</a>], followed by poly(A) elongation. After fertilization, uridylated short poly(A) tails of ribosomal proteins in morulae are re-elongated, forming non-canonical poly(A) tails. At the blastula stage, <span class="html-italic">cyclin B</span> mRNAs are deadenylated and uridylated. They are then degraded before gastrulation. Lower panel: Upper panel summarization. The arrow numbers correspond to those in the upper panel. Uridylated mRNAs are stable but inactive for translation. Canonical or non-canonical polyadenylation renders inactive mRNAs stably active for translation. Alternatively, uridylated mRNAs become unstable and inactive, followed by decay, as observed in other animals. (<b>B</b>) Proposed model for uridylation in starfish. Uridylated mRNAs are required to determine mRNA fate: destruction or recycling.</p>
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19 pages, 5110 KiB  
Article
Curcumin and Its Potential to Target the Glycolytic Behavior of Lactate-Acclimated Prostate Carcinoma Cells with Docetaxel
by Dongsic Choi, Jun Gi Lee, Su-Hak Heo, Moon-Kyen Cho, Hae-Seon Nam, Sang-Han Lee and Yoon-Jin Lee
Nutrients 2024, 16(24), 4338; https://doi.org/10.3390/nu16244338 - 16 Dec 2024
Viewed by 447
Abstract
Background: Dysregulated cellular metabolism is known to be associated with drug resistance in cancer treatment. Methods: In this study, we investigated the impact of cellular adaptation to lactic acidosis on intracellular energy metabolism and sensitivity to docetaxel in prostate carcinoma (PC) cells. The [...] Read more.
Background: Dysregulated cellular metabolism is known to be associated with drug resistance in cancer treatment. Methods: In this study, we investigated the impact of cellular adaptation to lactic acidosis on intracellular energy metabolism and sensitivity to docetaxel in prostate carcinoma (PC) cells. The effects of curcumin and the role of hexokinase 2 (HK2) in this process were also examined. Results: PC-3AcT and DU145AcT cells that preadapted to lactic acid displayed increased growth behavior, increased dependence on glycolysis, and reduced sensitivity to docetaxel compared to parental PC-3 and DU145 cells. Molecular analyses revealed activation of the c-Raf/MEK/ERK pathway, upregulation of cyclin D1, cyclin B1, and p-cdc2Thr161, and increased levels and activities of key regulatory enzymes in glycolysis, including HK2, in lactate-acclimated cells. HK2 knockdown resulted in decreased cell growth and glycolytic activity, decreased levels of complexes I–V in the mitochondrial electron transport chain, loss of mitochondrial membrane potential, and depletion of intracellular ATP, ultimately leading to cell death. In a xenograft animal model, curcumin combined with docetaxel reduced tumor size and weight, induced downregulation of glycolytic enzymes, and stimulated the upregulation of apoptotic and necroptotic proteins. This was consistent with the in vitro results from 2D monolayer and 3D spheroid cultures, suggesting that the efficacy of curcumin is not affected by docetaxel. Conclusions: Overall, our findings suggest that metabolic plasticity through enhanced glycolysis observed in lactate-acclimated PC cells may be one of the underlying causes of docetaxel resistance, and targeting glycolysis by curcumin may provide potential for drug development that could improve treatment outcomes in PC patients. Full article
(This article belongs to the Special Issue Effects of Plant Extracts on Human Health)
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<p>Increased glycolytic flux in PC-3AcT and DU145AcT cells pre-adapted to lactic acid. Cellular responses were examined after culturing cells in DMEM containing 3.8 μM lactic acid for the indicated time (or 48 h, otherwise). (<b>A</b>) Percent cell viability. (<b>B</b>–<b>D</b>) Western blot analysis of cell cycle-regulatory (<b>B</b>), MEK/ERK signaling (<b>C</b>), and key regulatory enzymes in glycolysis (<b>D</b>). (<b>E</b>) Activities of hexokinase and pyruvate dehydrogenase. (<b>F</b>) Changes in glucose concentration in culture medium. Data are expressed as the mean ± standard deviation of three independent experiments. Statistical significance comparing respective PC-3 or DU145 cells was considered at * <span class="html-italic">p</span> &lt; 0.05 using one-way ANOVA and Tukey’s post hoc correction. HK, hexokinase; PFKP, phosphofructokinase platelet; PDH, pyruvate dehydrogenase.</p>
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<p>Increased glycolytic flux in PC-3AcT and DU145AcT cells pre-adapted to lactic acid. Cellular responses were examined after culturing cells in DMEM containing 3.8 μM lactic acid for the indicated time (or 48 h, otherwise). (<b>A</b>) Percent cell viability. (<b>B</b>–<b>D</b>) Western blot analysis of cell cycle-regulatory (<b>B</b>), MEK/ERK signaling (<b>C</b>), and key regulatory enzymes in glycolysis (<b>D</b>). (<b>E</b>) Activities of hexokinase and pyruvate dehydrogenase. (<b>F</b>) Changes in glucose concentration in culture medium. Data are expressed as the mean ± standard deviation of three independent experiments. Statistical significance comparing respective PC-3 or DU145 cells was considered at * <span class="html-italic">p</span> &lt; 0.05 using one-way ANOVA and Tukey’s post hoc correction. HK, hexokinase; PFKP, phosphofructokinase platelet; PDH, pyruvate dehydrogenase.</p>
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<p>Mitochondrial localization of HK2 and effect of docetaxel treatment on PC-3AcT and DU145AcT cells. Cells were cultured in DMEM containing 3.8 μM lactic acid with or without docetaxel (40 nM) for 48 h. (<b>A</b>) Western blot analysis of HK2 in mitochondrial and cytosolic fractions. (<b>B</b>) Western blot analysis of complexes I–V in the mitochondrial electron transport chain. (<b>C</b>) Measurement of mitochondrial membrane potential after staining cells with rhodamine123. (<b>D</b>) Changes in intracellular ATP concentration. (<b>E</b>) Percent cell viability for cells treated with or without 40 nM docetaxel. (<b>F</b>) Annexin V-PE binding assay for cells treated with or without 40 nM docetaxel. (<b>G</b>) Measurements of mitochondrial membrane potential for cells treated with or without 40 nM docetaxel. Data are expressed as the mean ± standard deviation of three independent experiments. Statistical significance comparing respective PC-3 or DU145 cells was considered at * <span class="html-italic">p</span> &lt; 0.05 using one-way ANOVA and Tukey’s post hoc correction. HK2, hexokinase 2; VDAC, voltage-dependent anion channel; NDUFB8, NADH-ubiquinone oxidoreductase subunit B8 (complex I); SDHB, succinate dehydrogenase complex iron sulfur subunit B (complex II); UQCRC2, ubiquinone-cytochrome C reductase core protein 2 (complex III); COX II, mitochondrial cytochrome C oxidase subunit II (complex IV); ATP5A, ATP synthase F1 subunit alpha (complex V); DTX, docetaxel.</p>
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<p>Mitochondrial localization of HK2 and effect of docetaxel treatment on PC-3AcT and DU145AcT cells. Cells were cultured in DMEM containing 3.8 μM lactic acid with or without docetaxel (40 nM) for 48 h. (<b>A</b>) Western blot analysis of HK2 in mitochondrial and cytosolic fractions. (<b>B</b>) Western blot analysis of complexes I–V in the mitochondrial electron transport chain. (<b>C</b>) Measurement of mitochondrial membrane potential after staining cells with rhodamine123. (<b>D</b>) Changes in intracellular ATP concentration. (<b>E</b>) Percent cell viability for cells treated with or without 40 nM docetaxel. (<b>F</b>) Annexin V-PE binding assay for cells treated with or without 40 nM docetaxel. (<b>G</b>) Measurements of mitochondrial membrane potential for cells treated with or without 40 nM docetaxel. Data are expressed as the mean ± standard deviation of three independent experiments. Statistical significance comparing respective PC-3 or DU145 cells was considered at * <span class="html-italic">p</span> &lt; 0.05 using one-way ANOVA and Tukey’s post hoc correction. HK2, hexokinase 2; VDAC, voltage-dependent anion channel; NDUFB8, NADH-ubiquinone oxidoreductase subunit B8 (complex I); SDHB, succinate dehydrogenase complex iron sulfur subunit B (complex II); UQCRC2, ubiquinone-cytochrome C reductase core protein 2 (complex III); COX II, mitochondrial cytochrome C oxidase subunit II (complex IV); ATP5A, ATP synthase F1 subunit alpha (complex V); DTX, docetaxel.</p>
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<p>Effect of HK2 knockdown alone or in combination with curcumin on glucose metabolism in PC-3AcT and Du145AcT cells. Cells were transfected with 10 nM HK2-targeting siRNA (siHK2) or stealth RNAi control (siC) for 24 h. They were then treated with or without curcumin (40 μM) in DMEM containing 3.8 μM lactic acid for 48 h. (<b>A</b>) Percent cell viability. (<b>B</b>) Western blot analysis of key regulatory enzymes in glycolysis. (<b>C</b>) Activities of hexokinase and pyruvate dehydrogenase. (<b>D</b>) Changes in glucose concentration in culture medium. (<b>E</b>) Western blot analysis of HK2 in mitochondrial and cytosolic fractions. The bar graph represents densitometric analysis of Western blot images normalized to β-actin. Data are expressed as the mean ± standard deviation of three independent experiments. Statistical significance comparing the respective siC group was considered at * <span class="html-italic">p</span> &lt; 0.05 using one-way ANOVA and Tukey’s post hoc correction. CCM, curcumin; HK, hexokinase; PFKP, phosphofructokinase platelet; PDH, pyruvate dehydrogenase.</p>
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<p>Effects of HK2 knockdown alone or in combination with curcumin on mitochondrial function and programmed cell death in PC-3AcT and Du145AcT cells. Cells were transfected with 10 nM HK2-targeting siRNA (siHK2) or stealth RNAi control (siC) for 24 h. They were then treated with or without curcumin (40 μM) in DMEM containing 3.8 μM lactic acid for 48 h. (<b>A</b>) Western blot analysis of complexes I–V in mitochondrial electron transport chain. (<b>B</b>) Measurements of mitochondrial membrane potential after staining cells with rhodamine123. (<b>C</b>) Changes in intracellular ATP concentration. (<b>D</b>) Cell cycle analysis. (<b>E</b>) Annexin V-PE binding assay. (<b>F</b>) Western blot analysis of apoptosis- and necroptosis-related proteins. Data are expressed as the mean ± standard deviation of three independent experiments. Statistical significance comparing the respective siC group was considered at * <span class="html-italic">p</span> &lt; 0.05 using one-way ANOVA and Tukey’s post hoc correction. CCM, curcumin; NDUFB8, NADH-ubiquinone oxidoreductase subunit B8 (complex I); SDHB, succinate dehydrogenase complex iron sulfur subunit B (complex II); UQCRC2, ubiquinone-cytochrome C reductase core protein 2 (complex III); COX II, mitochondrial cytochrome C oxidase subunit II (complex IV); ATP5A, ATP synthase F1 subunit alpha (complex V).</p>
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<p>Growth-inhibiting effect of co-treatment with curcumin and docetaxel. (<b>A</b>) Cell viability in 2D monolayer culture. Cells were cultured in DMEM containing 3.8 μM lactic acid with or without curcumin (40 μM) and docetaxel (40 nM) for 48 h. (<b>B</b>) Vitality staining of spheroids: from left to right: (i) phase-contrast image, (ii) fluorescent images of fluorescein diacetate(+) living cells in green, (iii) propidium iodide(+) dead cells in red, and (iv) merged; and spheroid cell viability. Spheroids were then treated with or without curcumin (40 µM) and docetaxel (40 nM) for 48 h in DMEM containing 3.8 μM lactic acid. (<b>C</b>) Representative mice, body weight, tumor volume, and tumor weight in PC-3-xenografted nude mice model. Mice (0.3–0.4 cm wide and 0.3–0.4 cm long) were injected intratumorally with vehicle or curcumin (15 mg/kg) and docetaxel (0.5 mg/kg) three times per week for 24 days. Data are expressed as the mean ± standard deviation of three independent experiments. Statistical significance comparing the respective control group was considered at * <span class="html-italic">p</span> &lt; 0.05 using one-way ANOVA and Tukey’s post hoc correction. CCM/DTX, co-treatment with curcumin and docetaxel.</p>
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<p>Effects of co-treatment with curcumin and docetaxel on expression of glycolysis-, apoptosis-, and necroptosis-related key proteins in 2D monolayer, 3D spheroid cultures, and nude mice xenograft models. Proteins were extracted from cells, spheroids, and tumors described in <a href="#nutrients-16-04338-f005" class="html-fig">Figure 5</a>, separated on 4–12% NuPAGE gels, and subjected to Western blot analysis. (<b>A</b>) Expression levels of key regulatory enzymes of glycolysis. (<b>B</b>) Expression levels of proteins related to apoptosis and necroptosis. The bar graph represents densitometric analysis of Western blot images normalized to β-actin. Data are expressed as the mean ± standard deviation of three independent experiments. Statistical significance comparing the respective control group was considered at * <span class="html-italic">p</span> &lt; 0.05 using one-way ANOVA and Tukey’s post hoc correction. CCM/DTX, co-treatment with curcumin and docetaxel.</p>
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19 pages, 6915 KiB  
Article
RIPK4 Downregulation Reduces ABCG2 Expression, Increasing BRAF-Mutated Melanoma Cell Susceptibility to Cisplatin- and Doxorubicin-Induced Apoptosis
by Bartlomiej Olajossy, Norbert Wronski, Ewelina Madej, Joanna Komperda, Małgorzata Szczygieł and Agnieszka Wolnicka-Glubisz
Biomolecules 2024, 14(12), 1573; https://doi.org/10.3390/biom14121573 - 10 Dec 2024
Viewed by 557
Abstract
Melanoma cells remain resistant to chemotherapy with cisplatin (CisPt) and doxorubicin (DOX). The abnormal expression of Receptor-Interacting Protein Kinase 4 (RIPK4) in certain melanomas contributes to tumour growth through the NFκB and Wnt/β-catenin signalling pathways, which are known to regulate chemoresistance and recurrence. [...] Read more.
Melanoma cells remain resistant to chemotherapy with cisplatin (CisPt) and doxorubicin (DOX). The abnormal expression of Receptor-Interacting Protein Kinase 4 (RIPK4) in certain melanomas contributes to tumour growth through the NFκB and Wnt/β-catenin signalling pathways, which are known to regulate chemoresistance and recurrence. Despite this, the role of RIPK4 in response to chemotherapeutics in melanoma has not been reported. In this study, we examined how the downregulation and overexpression of RIPK4 affect the sensitivity of BRAF-mutated melanoma cells (A375 and WM266.4) to CisPt and DOX along with determining the underlying mechanism. Using two RIPK4 silencing methods (siRNA and CRISPR/Cas9) and overexpression (dCas9-VPR), we assessed CisPt and DOX-induced apoptosis using caspase 3/7 activity, annexin V/7AAD staining, and FASC analysis. In addition, qRT-PCR and Western blotting were used to detect apoptosis-related genes and proteins such as cleaved PARP, p53, and cyclin D1. We demonstrated that the overexpression of RIPK4 inhibits, while its downregulation enhances, CisPt- or DOX-induced apoptosis in melanoma cells. The effects of downregulation are similar to those observed with pre-incubation with cyclosporin A, an ABCG2 inhibitor. Additionally, our findings provide preliminary evidence of crosstalk between RIPK4, BIRC3, and ABCG2. The results of these studies suggest the involvement of RIPK4 in the observed resistance to CisPt or DOX. Full article
(This article belongs to the Special Issue Molecular Advances in Drug Resistance and Novel Therapies for Cancer)
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Figure 1

Figure 1
<p>The effect of RIPK4 silencing on CisPt-induced apoptosis of melanoma cells: (<b>A</b>) Viability of melanoma (BLM, WM266.4, A375, SKMEL-28) treated with cisplatin (CisPt) at 24 h using the MTT assay. (<b>B</b>) Efficiency of RIPK4 silencing in WM266.4 cells transfected with RIPK4.si1 RNA, or neg.si RNA was analysed after 48 h using Western blotting. (<b>C</b>–<b>E</b>) CisPt decreases WM266.4 viability and induced apoptosis 24 h after the treatment in both neg.si and RIPK4.si transfected cells. (<b>C</b>) MTT; <span class="html-italic">n</span> = 3, (<b>D</b>) caspase3/7 activity; <span class="html-italic">n</span> = 3 and (<b>E</b>) Annexin-V-FITC (AnxV)/7AAD double staining and FASC analysis. Dead cells (necrotic: 7AAD<sup>+</sup>, early apoptotic: AnxV<sup>+/</sup>7AAD<sup>−</sup> and late apoptotic: AnxV<sup>+</sup>/7AAD<sup>+</sup>); <span class="html-italic">n</span> = 3. Each bar represents the mean ± SD of three to four biological replicates. ns—not significant, # indicates <span class="html-italic">p</span> &lt; 0.05 vs. control (untreated cells), * indicates <span class="html-italic">p</span> &lt; 0.05 between the probes as marked by the line. Original images can be found in <a href="#app1-biomolecules-14-01573" class="html-app">Figure S1</a>.</p>
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<p>Stable downregulation of RIPK4 enhances apoptosis induced by CisPt-induced apoptosis in A375 and WM266.4 melanoma cells 24 h after the treatment: (<b>A</b>) The level of RIPK4 in A375<sup>RIPK4.KO</sup>, WM266.4<sup>RIPK4.KO</sup>cells, and their parental lines (wild-type, Wt). (<b>B</b>) Caspase3/7 activity, <span class="html-italic">n</span> = 3. (<b>C</b>) Annexin V-FITC (AnxV)/7AAD double staining and FASC analysis. (<b>D</b>) Dead cells (necrotic: 7AAD<sup>+</sup>, early apoptotic: AnxV<sup>+</sup>/7AAD<sup>−</sup>, and late apoptotic: AnxV<sup>+</sup>/7AAD<sup>+</sup>). Each bar represents the mean ± SD of three biological replicates. * <span class="html-italic">p</span> &lt; 0.05 were considered significant; ns—not significant. Original images can be found in <a href="#app1-biomolecules-14-01573" class="html-app">Figure S2</a>.</p>
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<p>CisPt and RIPK4.KO attenuates Wnt/β-catenin signalling in A375 melanoma cells 24 h after treatment: The protein levels of pAKT, AKT, pGSK3β, β-catenin, c-myc in knockout cells (RIPK4.KO) and their parental lines (Wt) were assessed using Western blotting with densitometry, <span class="html-italic">n</span> = 3. GAPDH servers as loading control. Each bar represents the mean ± SD of three biological replicates. * <span class="html-italic">p</span> &lt; 0.05 was considered significant. ns—not significant. Original images can be found in <a href="#app1-biomolecules-14-01573" class="html-app">Figure S3</a>.</p>
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<p>CisPt and RIPK4.KO attenuates Wnt/β-catenin signalling in WM266.4 melanoma cells 24 h after treatment. The protein levels of pAKT, AKT, pGSK-3β, β-catenin, and c-myc in knockout cells (RIPK4.KO) and their parental lines (Wt) were assessed using Western blotting with densitometry, <span class="html-italic">n</span> = 3. GAPDH servers as loading control. Each bar represents the mean ± SD of three biological replicates. * <span class="html-italic">p</span> &lt; 0.05 was considered significant. ns—not significant. Original images can be found in <a href="#app1-biomolecules-14-01573" class="html-app">Figure S4</a>.</p>
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<p>The effect of CRISPR/Cas9 mediated RIPK4 downregulation in A375 (right) and WM266.4 (left) cells on the expression of pro- and anti-apoptotic genes: Transcript levels of BIRC3, MCL-1, MT1X, and in A375<sup>RIPK4.KO</sup>, WM266.4<sup>RIPK4.KO</sup>cells and their parental lines normalised to GAPDH; <span class="html-italic">n</span> = 3. Each bar represents the mean ± SD of three to six biological replicates. * <span class="html-italic">p</span> &lt; 0.05 were considered significant; ns—not significant.</p>
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<p>The effect of CRISPR/Cas9 mediated RIPK4 downregulation in A375 and WM266.4 cells on BIRC3,-5 and MPRs proteins. The protein levels of BIRC5, BIRC3, ABCB1, ABCC1, and ABCG2 in knockout cells (RIPK4.KO) and their parental lines (Wt) were assessed using Western blotting with densitometry, <span class="html-italic">n</span> = 3. GAPDH servers as loading control. Each bar represents the mean ± SD of three to five biological replicates. * <span class="html-italic">p</span> &lt; 0.05 was considered significant. ns—not significant. Original images can be found in <a href="#app1-biomolecules-14-01573" class="html-app">Figure S5</a>.</p>
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<p>Effects of cyclosporin A and CRISPR/Cas9 mediated RIPK4 downregulation on CisPt-induced apoptosis of melanoma cells 24 h after the treatment: (<b>A</b>) Viability by MTT assay; <span class="html-italic">n</span> = 3. (<b>B</b>) caspase3/7 activity; <span class="html-italic">n</span> = 3. Each bar represents the mean ± SD of three biological replicates in duplicates. * <span class="html-italic">p</span> &lt; 0.05 were considered significant. (<b>C</b>) Protein levels of RIPK4, p53, cyclinD1, and total Poly (ADP-ribose) polymerase (PARP) after indicated time periods using Western blotting. GAPDH was used as a loading control. ns—not significant. Original images can be found in <a href="#app1-biomolecules-14-01573" class="html-app">Figure S6</a>.</p>
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<p>RIPK4 knockout enhances the pro-apoptotic effect of CisPt pre-stimulated cells with CsA: (<b>A</b>) A375<sup>RIPK4.KO</sup>, (<b>B</b>) WM266.4<sup>RIPK4.KO</sup> were pre-incubated for 1 h with CsA (5 μM) and CisPt (10 and 20 μM), or DMSO, as a control for 24 h. The cells viability by MTT assay, <span class="html-italic">n</span> = 3 (upper panel), caspase 3/7 activity (middle panel), <span class="html-italic">n</span> = 3. Each bar represents the mean ± SD of three biological replicates in duplicate. * <span class="html-italic">p</span> &lt; 0.05 were considered significant. Protein levels of p53, cyclin D1, and total Poly (ADP-ribose) polymerase (PARP) using Western blotting with densitometry (lower panel). GAPDH was used as loading control. ns—not significant. Original images can be found in <a href="#app1-biomolecules-14-01573" class="html-app">Figure S7</a>.</p>
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<p>RIPK4 knockout has a similar effect on DOX-induced melanoma cell apoptosis as pretreatment with CsA. A375 <sup>RIPK4.KO</sup>, WM266.4<sup>RIPK4.KO</sup>, and their wild-type (Wt) controls were pre-incubated for 1 h with CsA (5 μM) and then treated with DOX (4 μM), or DMSO, as a control, for 6–24 h. (<b>A</b>) Cell viability 24 h after treatment using MTT assay, <span class="html-italic">n</span> = 3; (<b>B</b>) caspase 3/7 activity, <span class="html-italic">n</span> = 3. Each bar represents the mean of at least three biological replicates ± SD. * <span class="html-italic">p</span> &lt; 0.05 were considered significant. (<b>C</b>) Protein levels of RIPK4, p53, cyclinD1, and total Poly(ADP-ribose) polymerase (PARP) after indicated time periods using Western blotting with densitometry. GAPDH was used as loading control. ns—not significant. Original images can be found in <a href="#app1-biomolecules-14-01573" class="html-app">Figure S8</a>.</p>
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<p>RIPK4 overexpression in A375-dCas9 cells attenuates sensitivity to CisPt and DOX. A375-dCas9 cells were transfected with two single sgRNAs targeting RIPK4 (RIPK4.sg1, RIPK4.sg2) or no targeting control (neg.sg). After 72 h of transfection, cells were incubated with CisPt (20 μM) or DOX (4 μM), or DMSO, as a control, for 24 h. (<b>A</b>,<b>B</b>) The expression levels of RIPK4 and ABCG2 were analysed using Western blotting along with densitometry, <span class="html-italic">n</span> = 3. GAPDH was used as a loading control. (<b>C</b>) The expression levels of RIPK4, p53, cyclin D1, and total Poly (ADP-ribose) polymerase (PARP) were analysed using Western blotting. GAPDH was used as a loading control. (<b>D</b>) Caspase3/7 activity assay after 24 h. <span class="html-italic">n</span> = 3 in duplicate. (<b>E</b>) Cell viability using MTT assay, <span class="html-italic">n</span> = 3. Each bar represents the mean ± SD of two biological replicates in triplicates. * <span class="html-italic">p</span> &lt; 0.05 were considered significant. Original images can be found in <a href="#app1-biomolecules-14-01573" class="html-app">Figure S9</a>.</p>
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17 pages, 2210 KiB  
Article
TCF12 and LncRNA MALAT1 Cooperatively Harness High Cyclin D1 but Low β-Catenin Gene Expression to Exacerbate Colorectal Cancer Prognosis Independently of Metastasis
by Chia-Ming Wu, Chung-Hsing Chen, Kuo-Wang Tsai, Mei-Chen Tan, Fang-Yu Tsai, Shih-Sheng Jiang, Shang-Hung Chen, Wei-Shone Chen, Horng-Dar Wang and Tze-Sing Huang
Cells 2024, 13(24), 2035; https://doi.org/10.3390/cells13242035 - 10 Dec 2024
Viewed by 592
Abstract
Metastasis is a well-known factor worsening colorectal cancer (CRC) prognosis, but mortality mechanisms in non-metastatic patients with poor outcomes are less understood. TCF12 is a transcription factor that can be physically associated with the long non-coding RNA MALAT1, creating an alliance with correlated [...] Read more.
Metastasis is a well-known factor worsening colorectal cancer (CRC) prognosis, but mortality mechanisms in non-metastatic patients with poor outcomes are less understood. TCF12 is a transcription factor that can be physically associated with the long non-coding RNA MALAT1, creating an alliance with correlated expression levels in CRC patients. This TCF12–MALAT1 alliance is linked to poorer prognosis independently of age and metastasis. To identify the downstream effects responsible for this outcome, we analyzed 2312 common target genes of TCF12 and MALAT1, finding involvement in pathways like Aurora B, ATM, PLK1, and non-canonical WNT. We investigated the impact of WNT downstream genes CTNNB1 and CCND1, encoding β-catenin and cyclin D1, respectively, on survival in CRC patients with this alliance. Tumors with higher TCF12 and MALAT1 gene expressions alongside increased β-catenin gene expressions were classified as having a “Pan-CMS-2 pattern”, showing relatively better prognoses. Conversely, tumors with high TCF12, MALAT1, and cyclin D1 gene expressions but low β-catenin expression were categorized as “TMBC pattern”, associated with poor survival, with survival rates dropping sharply from 60% at one year to 30% at three years. This suggests that targeting cyclin D1-associated CDK4/6 could potentially reduce early mortality risks in TMBC patients, supporting personalized medicine approaches. Full article
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Figure 1
<p>TCF12 cooperates with MALAT1 to exacerbate CRC prognosis. (<b>A</b>) Identification of MALAT1 as a TCF12-associated lncRNA by RNA immunoprecipitation (IP) and sequencing. After immunoblot analysis to confirm that TCF12 was specifically immunoprecipitated by the anti-TCF12 antibody from the lysate of SW620 cells, the anti-TCF12 immunoprecipitates were further subjected to the procedures of RNA extraction and next-generation sequencing. Several TCF12-associated lncRNAs were annotated after the sequence alignment analyses with NCBI and Ensembl databases. (<b>B</b>) Validation of MALAT1 as a TCF12-associated lncRNA. MALAT1 was detected by RT-PCR from the RNA sample isolated from the anti-TCF12 immunoprecipitates of SW620 cells. (<b>C</b>) ESTIMATE algorithm was used to estimate the tumor purities of the CRC specimens employed by the GA and HiSeq platforms of the TCGA-COAD dataset. (<b>D</b>) Univariate Cox regression analyses showing that age, metastasis, and expression levels of TCF12 mRNA and MALAT1 under an alliance but not alone were significantly associated with patients’ shorter overall survival outcomes. The interaction term of TCF12 mRNA and MALAT1 expression levels, designated as “TCF12 × MALAT1”, was represented as three covariates in a multivariate Cox regression analysis: TCF12 mRNA expression level (designated as “TCF12”), MALAT1 expression level (designated as “MALAT1”), and the multiplication of TCF12 mRNA and MALAT1 expression levels (designated as “TCF12 ⦁ MALAT1”). (<b>E</b>) Multivariate Cox regression analysis showing that the association of the TCF12–MALAT1 alliance with CRC poorer prognosis remained statistically significant after adjusting for patients’ age and tumor metastasis.</p>
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<p>The TCF12–MALAT1 alliance is associated with <span class="html-italic">β-catenin</span>-independent <span class="html-italic">cyclin D1</span> expression. (<b>A</b>) A group of 2312 genes, designated as TCF12 and MALAT1 common target genes, were obtained by examining the overlap between the total 15,373 genes identified from anti-TCF12 ChIP and DNA sequencing [<a href="#B3-cells-13-02035" class="html-bibr">3</a>] and the list of 2650 MALAT1 target genes of the UALCAN website (University of Alabama at Birmingham) [<a href="#B45-cells-13-02035" class="html-bibr">45</a>]. They include <span class="html-italic">WNT2B</span>, <span class="html-italic">β-catenin</span>, <span class="html-italic">cyclin D1</span>, and <span class="html-italic">c-myc</span> genes. (<b>B</b>) The 2312 genes were analyzed by MGSA signal pathway enrichment. The significantly enriched pathways contain the non-canonical WNT pathway. (<b>C</b>) Pearson’s correlation analyses of the levels of TCF12 mRNA, MALAT1, β-catenin mRNA, cyclin D1 mRNA, and c-Myc mRNA in all 193 patients or the different subsets of patients classified based on the CMS criteria. (<b>D</b>) Kaplan–Meier OS curves of the 184 TCGA-COAD (GA) patients classified into 4 subtypes of the CMS system. The CMS-2 patients exhibited a better prognosis, but the CMS-1 and CMS-4 patients had relatively low OS rates. (<b>E</b>) The expression statuses of β-catenin and cyclin D1 mRNA in different CMS subtypes of the 59 patients with higher levels (&gt;median) of TCF12 mRNA and MALAT1 expressions (designated as “TCF12<sup>hi</sup>MALAT1<sup>hi</sup>”). The CMS-2 patients trended to express higher levels (&gt;median) of β-catenin mRNA but not cyclin D1 mRNA; however, other subtypes of patients seemed to express higher levels (&gt;median) of cyclin D1 mRNA instead of β-catenin mRNA.</p>
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<p><span class="html-italic">β-catenin</span> and <span class="html-italic">cyclin D1</span> gene expression affect the association of the TCF12–MALAT1 alliance with CRC patients’ poorer survival outcomes. (<b>A</b>) Kaplan–Meier OS curves of the 61 TCGA-COAD (GA) TCF12<sup>hi</sup>MALAT1<sup>hi</sup> patients who were divided into two groups based on the β-catenin mRNA expression level &gt; or ≤ median. Low β-catenin mRNA expression was significantly associated with shorter OS in the TCF12<sup>hi</sup>MALAT1<sup>hi</sup> patients (<span class="html-italic">p</span> = 0.004 by the log-rank test). (<b>B</b>) Kaplan–Meier OS curves of the 193 TCGA-COAD (GA) patients who were divided into two groups based on the patients with or without the status of higher TCF12 mRNA expression, higher MALAT1 expression, but low β-catenin mRNA expression (designated as “TCF12<sup>hi</sup>MALAT1<sup>hi</sup>β-catenin<sup>lo</sup>”). The patients with the TCF12<sup>hi</sup>MALAT1<sup>hi</sup>β-catenin<sup>lo</sup> expression status significantly exhibited a poorer prognosis when compared with other patients (<span class="html-italic">p</span> = 0.017 by the log-rank test). (<b>C</b>) Kaplan–Meier OS curves of the 61 TCGA-COAD (GA) TCF12<sup>hi</sup>MALAT1<sup>hi</sup> patients who were divided into two groups based on the cyclin D1 mRNA expression level &gt; or ≤ median. The patients with high cyclin D1 mRNA expression had a worse OS rate (<span class="html-italic">p</span> = 0.041 by the log-rank test). (<b>D</b>) Kaplan–Meier OS curves of the 193 TCGA-COAD (GA) patients who were divided into two groups based on the patients with or without the status of higher TCF12 mRNA expression, MALAT1 expression, and cyclin D1 mRNA expression (designated as “TCF12<sup>hi</sup>MALAT1<sup>hi</sup>cyclin D1<sup>hi</sup>”). The patients’ OS between the two groups showed no significant difference.</p>
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<p>The TCF12–MALAT1 alliance exacerbates CRC prognosis via low <span class="html-italic">β-catenin</span> but high <span class="html-italic">cyclin D1</span> gene expression. (<b>A</b>) Kaplan–Meier OS curves of the 33 TCGA-COAD (GA) TCF12<sup>hi</sup>MALAT1<sup>hi</sup>β-catenin<sup>hi</sup> patients who were divided into two groups based on the cyclin D1 mRNA expression level&gt; or ≤median. High cyclin D1 mRNA expression did not significantly worsen the OS of TCF12<sup>hi</sup>MALAT1<sup>hi</sup>β-catenin<sup>hi</sup> patients. (<b>B</b>) Kaplan–Meier OS curves of the 28 TCGA-COAD (GA) TCF12<sup>hi</sup>MALAT1<sup>hi</sup>β-catenin<sup>lo</sup> patients who were divided into 2 groups based on the cyclin D1 mRNA expression level&gt; or ≤median. High cyclin D1 mRNA expression rendered the TCF12<sup>hi</sup>MALAT1<sup>hi</sup>β-catenin<sup>lo</sup> patients prone to shorter survival. (<b>C</b>) Kaplan–Meier OS curves of the 193 TCGA-COAD (GA) patients who were divided into two groups based on the patients with or without the status of higher TCF12 mRNA expression, higher MALAT1 expression, low β-catenin mRNA expression, and higher cyclin D1 mRNA expression (designated as “TCF12<sup>hi</sup>MALAT1<sup>hi</sup>β-catenin<sup>lo</sup>cyclin D1<sup>hi</sup>” or “TMBC pattern”). The patients with the TMBC pattern significantly exhibited a poorer prognosis when compared with other patients (<span class="html-italic">p</span> &lt; 0.001 by the log-rank test). (<b>D</b>) Univariate and multivariate Cox regression analyses showing that the TMBC pattern is a metastasis-independent prognostic factor with an even higher hazard ratio. (<b>E</b>) A nomogram arose based on the effect levels of TMBC vs. metastasis on the OS of 193 TCGA-COAD (GA) patients. When the TMBC score was 100, metastasis reached a score of 83, suggesting that the TMBC pattern serves as a higher risk factor rather than metastasis. (<b>F</b>) Kaplan–Meier RFS curves of the 193 TCGA-COAD (GA) patients who were divided into two groups based on the patients with or without the TMBC pattern. The patients with the TMBC pattern significantly exhibited a shorter RFS outcome when compared with other patients (<span class="html-italic">p</span> = 0.024 by the log-rank test).</p>
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<p>A schematic illustration summarizing our studies of whether the TCF12–MALAT1 alliance and its downstream β-catenin and cyclin D1 determine a good or poor CRC prognosis. TCF12 is a transcriptional factor involved in numerous cellular processes. MALAT1 is a long lncRNA that can form a complex with TCF12, creating an alliance with correlated expression levels in CRC patients. This TCF12–MALAT1 alliance is linked to poorer prognosis independently of age and metastasis status. To identify the downstream factors/events responsible for this outcome, we analyzed 2312 common target genes of TCF12 and MALAT1 through MGSA pathway enrichment analysis, finding involvement in pathways like Aurora B, ATM, PLK1, and non-canonical WNT. We further investigated the impact of WNT downstream genes <span class="html-italic">β-catenin</span> and <span class="html-italic">cyclin D1</span> on survival in CRC patients with the TCF12–MALAT1 alliance. Our analysis of the TCGA-COAD (GA) dataset revealed that 61 out of 193 patients had tumors with the “TCF12<sup>hi</sup>MALAT1<sup>hi</sup>” expression status. Furthermore, 33 out of 61 patients had higher β-catenin mRNA levels in tumors. They were classified as having a “Pan-CMS-2 pattern” and exhibited better survival outcomes. For the other 28 patients with low expression levels of β-catenin mRNA in tumors, 16 out of them expressed higher levels of cyclin D1 mRNA in tumors, i.e., the “TCF12<sup>hi</sup>MALAT1<sup>hi</sup>β-catenin<sup>lo</sup>cyclin D1<sup>hi</sup>” expression status or the so-called “TMBC pattern”. They exhibited poorer RFS and OS outcomes independently of metastasis. Early tumor recurrence seemed to be a mortality risk to these TMBC patients.</p>
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14 pages, 10213 KiB  
Article
Counteractive Effects of Copper Nanoparticles and Betacellulin on Ovarian Cells
by Alexander V. Sirotkin, Paula Romero-Navarro, Barbora Loncová, Zuzana Fabová, Michaela Bartušová, Abdel Halim Harrath and Francisco Alonso
Nanomaterials 2024, 14(23), 1965; https://doi.org/10.3390/nano14231965 - 7 Dec 2024
Viewed by 696
Abstract
Copper nanoparticles (CuNPs) are known to affect many ovarian cell functions. CuNPs, prepared using a chemical reduction method, were fully characterized by different means (TEM, DLS, XRD, Z potential, XPS, and AES). The resulting colloidal suspension contained needle-like CuNPs aggregates made of a [...] Read more.
Copper nanoparticles (CuNPs) are known to affect many ovarian cell functions. CuNPs, prepared using a chemical reduction method, were fully characterized by different means (TEM, DLS, XRD, Z potential, XPS, and AES). The resulting colloidal suspension contained needle-like CuNPs aggregates made of a core of metallic copper and an oxidized surface of Cu2O and CuO. The separate and coupled effects of CuNPs and the growth factor betacellulin (BTC) were analyzed on the control of some basic functions of ovarian cells. With this purpose, porcine ovarian granulosa cells, together with CuNPs, BTC, and both (CuNPs + BTC), were cultured. Viability and BrDU tests, quantitative immunocytochemistry, TUNEL, and ELISA were used to evaluate markers of the S-phase (PCNA) and G-phase (cyclin B1) of the cell cycle, cell proliferation (BrDU incorporation), cytoplasmic/mitochondrial apoptosis (bax) and extrinsic (nuclear DNA fragmentation) markers, and the release of estradiol and progesterone. CuNPs were accumulated within the cells and were found to reduce all the markers of proliferation, but promoted all the markers of apoptosis and the release of steroid hormones. When added alone, BTC raised the expression of all cell viability and proliferation markers, depleted the expression of all apoptosis markers, and stimulated the release of both estradiol and progesterone. Furthermore, BTC prevented and even reversed the effect of CuNPs on all the measured parameters, whereas CuNPs mitigated BTC’s effect on all the analyzed cell functions. These results support a direct toxic effect of CuNPs and a stimulatory effect of BTC on ovarian cell functions, as well as the capability of BTC to protect against the adverse effects of CuNPs. Full article
(This article belongs to the Special Issue Advances in Toxicity of Nanoparticles in Organisms (2nd Edition))
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Graphical abstract

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<p>TEM micrographs of CuNPs.</p>
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<p>DLS graphic of CuNPs.</p>
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<p>(<b>a</b>) The needle width estimated by TEM for CuNPs; the comparative distribution of main needles and sub-needles is not significant, as some of the sub-needles were measured inside the main needles. (<b>b</b>) The Z potential graphic of CuNPs.</p>
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<p>XRD spectrum of CuNPs (<b><span style="color:red">*</span></b> denotes fcc Cu).</p>
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<p>(<b>a</b>) XPS spectrum (Cu 2<span class="html-italic">p</span><sub>3/2</sub> level) and (<b>b</b>) CuL<sub>3</sub>M<sub>45</sub>M<sub>45</sub> Auger energy spectrum of CuNPs.</p>
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<p>The incorporation of CuNPs into porcine ovarian granulosa cells cultured with CuNPs given at different doses. (<b>A</b>) The percentage of cells containing CuNPs. The results show (a) the effects of CuNPs: a significant (<span class="html-italic">p</span> &lt; 0.05) difference between the cells treated and not treated with CuNPs (CuNPs at a dose of 0 ng/mL). The results are expressed as the mean ± SEM. (<b>B</b>–<b>E</b>) Representative images of cells cultured with CuNPs at different doses: 0 ng/mL (<b>B</b>), 1 ng/mL (<b>C</b>), 10 ng/mL (<b>D</b>), and 100 ng/mL (<b>E</b>).</p>
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<p>The effects of CuNPs, betacellulin (BTC), and both together on (<b>A</b>) cell viability, (<b>B</b>) BrdU incorporation, (<b>C</b>) PCNA accumulation, (<b>D</b>) cyclin B1, (<b>E</b>) fragmentation of DNA, (<b>F</b>) bax accumulation, (<b>G</b>) caspase 3 accumulation, and (<b>H</b>) progesterone and (<b>I</b>) estradiol release in cells from porcine ovary. The recorded data show (a) the effects of CuNPs, with a significant (<span class="html-italic">p</span> &lt; 0.05) difference between the treated and untreated cells with CuNPs (CuNPs at a dose of 0 ng/mL); (b) the effect of BTC, with a significant difference (<span class="html-italic">p</span> &lt; 0.05) between the cultured and non-cultured groups of cells with BTC. All the results are depicted as the mean ± SEM.</p>
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30 pages, 13074 KiB  
Article
An Azomethine Derivative, BCS3, Targets XIAP and cIAP1/2 to Arrest Breast Cancer Progression Through MDM2-p53 and Bcl-2-Caspase Signaling Modulation
by Reetuparna Acharya, Pran Kishore Deb, Katharigatta N. Venugopala and Shakti Prasad Pattanayak
Pharmaceuticals 2024, 17(12), 1645; https://doi.org/10.3390/ph17121645 - 6 Dec 2024
Viewed by 564
Abstract
Background: Breast cancer influences more than 2 million women worldwide annually. Since apoptotic dysregulation is a cancer hallmark, targeting apoptotic regulators encompasses strategic drug development for cancer therapy. One such class of apoptotic regulators is inhibitors of apoptosis proteins (IAP) which are [...] Read more.
Background: Breast cancer influences more than 2 million women worldwide annually. Since apoptotic dysregulation is a cancer hallmark, targeting apoptotic regulators encompasses strategic drug development for cancer therapy. One such class of apoptotic regulators is inhibitors of apoptosis proteins (IAP) which are a class of E3 ubiquitin ligases that actively function to support cancer growth and survival. Methods: The current study reports design, synthesis, docking analysis (based on binding to IAP-BIR3 domains), anti-proliferative and anti-tumor potential of the azomethine derivative, 1-(4-chlorophenyl)-N-(4-ethoxyphenyl)methanimine (BCS3) on breast cancer (in vitro and in vivo) and its possible mechanisms of action. Results: Strong selective cytotoxic activity was observed in MDA-MB-231, MCF-7, and MDA-MB-468 breast cancer cell lines that exhibited IC50 values, 1.554 µM, 5.979 µM, and 6.462 µM, respectively, without affecting normal breast cells, MCF-10A. For the evaluation of the cytotoxic potential of BCS3, immunofluorescence, immunoblotting, and FACS (apoptosis and cell cycle) analyses were conducted. BCS3 antagonized IAPs, thereby causing MDM2-p53 and Bcl-2-Caspase-mediated intrinsic and extrinsic apoptosis. It also modulated p53 expression causing p21-CDK1/cyclin B1-mediated cell cycle arrest at S and G2/M phases. The in vitro findings were consistent with in vivo findings as observed by reduced tumor volume and apoptosis initiation (TUNEL assay) by IAP downregulation. BCS3 also produced potent synergistic effects with doxorubicin on tumor inhibition. Conclusions: Having witnessed the profound anti-proliferative potential of BCS3, the possible adverse effects related to anti-cancer therapy were examined following OECD 407 guidelines which confirmed its systemic safety profile and well tolerability. The results indicate the promising effect of BCS3 as an IAP antagonist for breast cancer therapy with fewer adverse effects. Full article
(This article belongs to the Special Issue Potential Therapeutic Targets for the Treatment of Pathological Pain)
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Figure 1
<p>The in silico molecular docking studies of BCS3 with IAPs that represent (<b>A</b>) 2D and 3D docked poses of <b>BCS3</b> with inhibitors of apoptosis proteins (XIAP (PDB ID: 3CLX), cIAP1 (PDB ID: 3MUP) and cIAP2 (PDB ID: 3M0A). In silico ADME prediction representing (<b>B</b>) BOILED-Egg model of <b>BCS3</b> (<b>C</b>) SwissADME bioavailability radar report of <b>BCS3</b> and (<b>D</b>) Prediction of possible metabolites of <b>BCS3</b> by Phase I biotransformation.</p>
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<p>Cytotoxic effects of various concentrations of <b>BCS3</b> on the proliferation of breast cancer cells, (<b>A</b>) MDA-MB-231, (<b>B</b>) MCF-7, and (<b>C</b>) MDA-MB-468 through MTT assay for 24 h. (<b>D</b>) Time-course study of proliferation of MDA-MB-231 cells after incubation with varying doses of <b>BCS3</b> (0.8, 1.6, and 3.2 µM) up to 96 h. Cell viability of the DMSO vehicle control group was set at 100%. Effect of varying doses of BCS3 (0.8, 1.6, and 3.2 µM) on the relative protein expressions of inhibitory apoptotic proteins (IAPs) as quantified by western blotting analysis in MDA-MB-231 cells (<b>E</b>) XIAP, (<b>F</b>) cIAP1, and cIAP2, respectively. Respective graphs represent each band of cIAP1 and cIAP2 measured by densitometry and normalized to corresponding p-97. (<b>G</b>) Protein analysis of MDM2 by ELISA in MDA-MB-231 cells. (<b>H</b>) Relative protein expression of p53 quantified by western blotting in MDA-MB-231 cells. The respective graph represents each band of XIAP, cIAP1, cIAP2, and p53 measured by densitometry and normalized to corresponding p-97. Mean ± SEM was calculated by replicating the experiment thrice (n = 3). Significant differences are shown as * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, with the control group.</p>
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<p>Relative protein expression of (<b>A</b>) MCL-1 quantified by western blotting in MDA-MB-231 cells. (<b>B</b>) Protein analysis of cytochrome c by ELISA in MDA-MB-231 cells. Relative protein expression of (<b>C</b>) SMAC, (<b>D</b>) Survivin, and (<b>E</b>) Apaf-1 quantified by western blotting in MDA-MB-231 cells. The respective graph represents each band of MCL-1, SMAC, Survivin, and Apaf-1 measured by densitometry and normalized to corresponding p-97 and β-actin. Cytotoxicity assessment through measurement of (<b>F</b>) ROS, (<b>G</b>) ATP content, and (<b>H</b>) lactate dehydrogenase (LDH) activity in MDA-MB-231 cells for 24 h post-treatment with varying doses of BCS3 (0.8, 1.6, and 3.2 µM). Mean ± SEM was calculated by replicating the experiment thrice (n = 3). Significant differences are shown as * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01 and *** <span class="html-italic">p</span> &lt; 0.001with the control group.</p>
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<p>Analysis of mitochondrial membrane potential of BCS3 on MDA-MB-231 cells verified using (<b>A</b>) JC-1 and (<b>B</b>) JC-10 levels. Mean ± SEM was calculated by replicating the experiment thrice (n = 3). Significant differences are shown as * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01 and *** <span class="html-italic">p</span> &lt; 0.001 with the control group. (<b>C</b>) Determination of apoptotic cell death in MDA-MB-231 cells documented by annexin V-Alexa Fluor 647 (a647)/PI double staining and FACS analysis after treatment with BCS3 (0.8, 1.6, and 3.2 µM). Annexin V[+] and PI[−]: apoptotic cells (N4); annexin V[+] and PI[+]: Late apoptotic cells (N2); annexin V[−] and PI[+]: necrotic cells (N1) and annexin V[−] and PI[−]: Living cells (N3). (<b>D</b>) Bar diagram depicting the percentage of apoptosis caused by a number of early and late apoptotic cellular populations after BCS3 treatment. Representation of western blot analysis showing the protein expression of (<b>E</b>) cleaved caspase-8, (<b>F</b>) cleaved caspase-3, and cleaved caspase-9 after 72 h of treatment with BCS3 (0.8, 1.6, and 3.2 µM). Respective graphs represent each band of caspases (3 and 9) measured by densitometry and normalized to corresponding α-tubulin and p-97. Mean ± SEM was calculated by replicating the experiment thrice (n = 3). Significant differences are shown as * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01 and *** <span class="html-italic">p</span> &lt; 0.001 with a control group.</p>
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<p>Immunofluorescence analysis depicting the elevation of (<b>A</b>) cleaved caspase-8 and (<b>B</b>) cleaved caspase-3 in vitro in MDA-MB-231 cells after 72 h of treatment with varying doses of BCS3 (1.6 and 3.2 µM) where Alexa 633 (red fluorescence) denotes caspase-3 and -8 expressions, respectively, and Hoechst (blue fluorescence) denotes cell nuclei locations. The scale bars of immunofluorescence analysis are represented as 10 µm.</p>
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<p>(<b>A</b>) Immunofluorescence analysis depicting the elevation of Bax in vitro in MDA-MB-231 cells after 72 h of treatment with varying doses of BCS3 (1.6 and 3.2 µM) where FITC (green fluorescence) denotes Bax expression and DAPI (light blue fluorescence) denotes cell nuclei locations. (<b>B</b>) Immunofluorescence analysis depicting the depletion of the Bcl-2 protein in vitro in MDA-MB-231 cells after 72 h of treatment with varying doses of BCS3 (1.6 and 3.2 µM) where Alexa 647 (red fluorescence) denotes Bcl-2 expression and DAPI (light blue fluorescence) denotes cell nuclei locations. The scale bars are represented as 20 µm.</p>
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<p>Flow cytometric analysis indicating (<b>A</b>) cell cycle progression of untreated MDA-MB-231 cells, the effect of different concentrations of BCS3 (0.8 µM, 1.6 µM and 3.2 µM) on MDA-MB-231 cells, (<b>B</b>) percentage of cell cycle distribution protein analysis of (<b>C</b>) p21, (<b>D</b>) phospho-CDK1, and (<b>E</b>) phospho-cyclin B1 by ELISA. Mean ± SEM was calculated through replicating the experiment thrice (n = 3). Significant differences are shown as * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01 and *** <span class="html-italic">p</span> &lt; 0.001 with the control group.</p>
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<p>(<b>A</b>) Effect of BCS3 on body weight (in grams) of DMBA-induced breast cancer in experimental rats. (<b>B</b>) Effect of BCS3 on tumor volume of DMBA-induced breast cancer in experimental rats. (<b>C</b>) Histopathological observation (400×) of hematoxylin and eosin (H&amp;E)-stained mammary tissues where scale bare represents the 50 µm section. Yellow arrows represent normal acini and ductules in normal groups. Black arrows show ductal hyperplasia in DMBA-treated group with abnormal tissue architecture. BCS3-treated groups show restoration of ductal architecture by yellow arrows. (<b>D</b>) Representation of TUNEL fluorescent images of a section of tumor excised from experimental animals from each group. Cell nuclei locations are indicated with Hoechst (blue fluorescence) and apoptotic cell location is indicated by Alexa Fluor 594 (purple fluorescence). The scale bars of immunofluorescence analysis are represented as 100 µm. (<b>E</b>) Evaluation of the rate of tumor cell apoptosis in mammary tissues of rats from each experimental group in accordance with images of TUNEL assay. Comparisons: a-Groups II, III, and IV with Group I; b-Groups III and IV compared to Group II; *** <span class="html-italic">p</span> &lt; 0.001, ** <span class="html-italic">p</span> &lt; 0.01 and * <span class="html-italic">p</span> &lt; 0.05. Group I: Control; Group II: induced control (DMBA, 20 mg in 0.5 mL of olive oil); Group III: DMBA (20 mg) + BCS3 (15 mg/kg, b.w); and Group IV: DMBA (20 mg) + BCS3 (30 mg/kg, b.w). DMBA: 7,12-dimethylbenz(a)anthracene.</p>
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<p>(<b>A</b>) Immunofluorescence analysis of Bax in mammary tissues belonging to cancer-bearing animals. Expression of Bax was observed to enhance upon BCS3 treatment which was observed by Alexa Fluor 488 (green fluorescence) representing Bax expression and DAPI (light-blue fluorescence) denoting cell nuclei locations. The scale bars of immunofluorescence analysis are represented as 20 µm. (<b>B</b>) Immunofluorescence analysis of cleaved caspase-3 in mammary tissues belonging to cancer-bearing animals. Expression of cleaved caspase-3 was observed to enhance upon BCS3 treatment which was observed by Alexa Fluor 647 (red fluorescence) representing cleaved caspase-3 expression and Hoechst (blue fluorescence) denoting cell nuclei locations. The scale bars of immunofluorescence analysis are represented as 20 µm. (<b>C</b>) Effect of BCS3 on protein expression of XIAP. Effect of BCS3 on expression of cell cycle proteins (<b>D</b>) p21, (<b>E</b>) phospho-CDK1, and (<b>F</b>) phospho-cyclin B1 on mammary tissues of experimental animals. Comparisons: a-Groups II, III, and IV with Group I; b-Groups III and IV compared to Group II; *** <span class="html-italic">p</span> &lt; 0.001, * <span class="html-italic">p</span> &lt; 0.05, and <sup>ns</sup> <span class="html-italic">p</span> &gt; 0.05. Group I: Control; Group II: induced control (DMBA, 20 mg in 0.5 mL of olive oil); Group III: DMBA (20 mg) + BCS3 (15 mg/kg, b.w); and Group IV: DMBA (20 mg) + BCS3 (30 mg/kg, b.w). DMBA: 7,12-dimethylbenz(a)anthracene.</p>
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<p>(<b>A</b>) Dose-inhibition response curve for BCS3 and doxorubicin output; (<b>B</b>) dose-response matrix (inhibition)/heat map for BCS3 and doxorubicin where the degree of red is positively related to inhibition ratio; (<b>C</b>) drug interaction landscape; and (<b>D</b>) synergy plot of combined treatment of BCS3 and doxorubicin calculated with zero interaction potency (ZIP) reference model of Synergyfinder.</p>
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<p>Representative photomicrograph of vital organs (liver, kidney, brain, and lungs) of normal experimental rats from repeated dose sub-acute oral toxicity study. Black arrows represent the presence of lipid droplets caused by hepatic steatosis. The kidney represents cloudy swelling (yellow arrows) and leukocytic infiltration as an effect of repeated administration of 300 mg/kg/day BCS3 dose. Group I: vehicle control group; Group II: 30 mg/kg/day of BCS3; Group III: 300 mg/kg/day of BCS3 (28 days); Group IV: satellite control group; and Group V: 300 mg/kg of BCS3 (satellite groups: 42 days); n = 5.</p>
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15 pages, 6750 KiB  
Article
Effects of Pterostilbene on the Cell Division Cycle of a Neuroblastoma Cell Line
by Francesca Bruno, Flores Naselli, Desiree Brancato, Sara Volpes, Paola Sofia Cardinale, Salvatore Saccone, Concetta Federico and Fabio Caradonna
Nutrients 2024, 16(23), 4152; https://doi.org/10.3390/nu16234152 - 29 Nov 2024
Viewed by 542
Abstract
Background. The “Cell Cycle Hypothesis” suggests that the abnormal re-entry of neurons into the cell division cycle leads to neurodegeneration, a mechanism supported by in vitro studies on neuronal-like cells treated with the hyperphosphorylating agent forskolin. Pterostilbene, a bioavailable compound found in foods [...] Read more.
Background. The “Cell Cycle Hypothesis” suggests that the abnormal re-entry of neurons into the cell division cycle leads to neurodegeneration, a mechanism supported by in vitro studies on neuronal-like cells treated with the hyperphosphorylating agent forskolin. Pterostilbene, a bioavailable compound found in foods such as blueberries and grapes, may exert neuroprotective effects and could serve as a potential adjunct therapy for neurodegenerative diseases. Methods. In this study, we investigated the effects of pterostilbene on neuronal-like cells derived from the human neuroblastoma SK-N-BE cell line, where cell cycle reactivation was induced by forskolin treatment. We analyzed molecular endpoints associated with differentiated versus replicative cell states, specifically the following: (a) the expression of cyclin CCND1, (b) the Ki67 cell proliferation marker, (c) the AT8 nuclear tau epitope, and (d) genome-wide DNA methylation changes. Results. Our findings indicate that pterostilbene exerts distinct effects on the cell division cycle depending on the cellular state, with neuroprotective benefits observed in differentiated neuronal-like cells, but not in cells undergoing induced division. Additionally, pterostilbene alters DNA methylation patterns. Conclusion. These results suggest that pterostilbene may offer neuroprotective advantages for differentiated neuronal-like cells. However, further studies are required to confirm these effects in vivo by examining specific biomarkers in human populations consuming pterostilbene-containing foods. Full article
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<p>Effect of pterostilbene on the cell cycle of SK-N-BE cells. Expression analysis of cyclin <span class="html-italic">CCND1</span> in replicative (<b>A</b>), differentiated (<b>B</b>), and differentiated with forskolin treatment (<b>C</b>). SK-N-BE cells were treated with pterostilbene 10 μM (Pt10) and 100 μM (Pt100) for 4 and 24 h. RQ: relative quantitation obtained by qRT-PCR using the 2<sup>−ΔΔCt</sup> method. C.I.: Confidence Interval. Control: treatment with DMSO; Fsk: forskolin; Fsk + Pt10: forskolin + pterostilbene 10 µM; Fsk + Pt100: forskolin + pterostilbene 100 µM. *: <span class="html-italic">p</span> &lt; 0.05, **: <span class="html-italic">p</span> &lt; 0.01, ***: <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>Effect of pterostilbene in SK-N-BE replicative cells. Immunolocalization of Ki67 proliferation marker (red signals) and AT8 tau epitope (green signals) in replicative cells after 4 h (<b>left panels</b>) and 24 h (<b>right panels</b>) of treatment with pterostilbene. Nuclei were stained with DAPI (blue). Images were captured by means of confocal laser scanning microscope at 400× magnification. Pt: pterostilbene. The scale bar, 20 μm for all the images, is located in the upper right panels.</p>
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<p>Effect of pterostilbene in differentiated SK-N-BE cells. Immunolocalization of Ki67 proliferation marker (red signals) and AT8 tau epitope (green signals) in differentiated SK-N-BE cells after 4 h (<b>left panels</b>) and 24 h (<b>right panels</b>) treatment with pterostilbene. Nuclei were stained with DAPI (blue). Images were captured by means of confocal laser scanning microscope at 400× magnification. Pt: pterostilbene. The scale bar, 20 μm for all the images, is located in the upper right panels.</p>
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<p>Effect of pterostilbene in SK-N-BE cells induced to cell cycle re-activation by forskolin. Immunolocalization of Ki67 proliferation marker (red signals) and AT8 tau epitope (green signals) in forskolin induced cells after 4 h (<b>left panels</b>) and 24 h (<b>right panels</b>) of pterostilbene treatment. Nuclei were stained with DAPI (blue). Images were captured by means of confocal laser scanning microscope at 400× magnification. Pt: pterostilbene. The scale bar, 20 μm for all the images, is located in the upper right panels.</p>
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<p>DNA methylation pattern on the SK-N-BE cells after 4 h of pterostilbene treatment. Representative MeSAP-PCR fingerprinting of replicative (<b>A</b>), differentiated (<b>C</b>), and forskolin-treated SK-N-BE cells (<b>E</b>) and the related graphic representations of the densitometry analysis (<b>B</b>, <b>D</b>, and <b>F</b> respectively). Control: cells treated with DMSO; Pt10 and P100: cells treated with pterostilbene 10 μM and 100 μM, respectively. Band pattern variation, in terms of intensification/weakening and appearance/disappearance, was evaluated by the densitometer scanning of mono-digested DNA (MD) in comparison with double-digested DNA (DD).</p>
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<p>DNA methylation pattern on the SK-N-BE cells after 24 h of pterostilbene treatment. Representative MeSAP-PCR fingerprinting of replicative (<b>A</b>), differentiated (<b>C</b>), and forskolin-treated SK-N-BE cells (<b>E</b>) and the related graphic representations of the densitometry analysis (<b>B</b>, <b>D</b>, and <b>F</b> respectively). Control: cells treated with DMSO; Pt10 and P100: cells treated with pterostilbene 10 μM and 100 μM, respectively. Band pattern variation, in terms of intensification/weakening and appearance/disappearance, was evaluated by the densitometer scanning of mono-digested DNA (MD) in comparison with double-digested DNA (DD).</p>
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12 pages, 4261 KiB  
Communication
Momordica charantia Extract Ameliorates Melanoma Cell Proliferation and Invasion into Mouse Lungs by Suppressing PAX3 Expression
by Keiichi Hiramoto and Hirotaka Oikawa
Int. J. Mol. Sci. 2024, 25(23), 12800; https://doi.org/10.3390/ijms252312800 - 28 Nov 2024
Viewed by 549
Abstract
Melanomas, which develop on malignant transformations of melanocytes, are highly malignant and prone to metastasis; therefore, effective drugs are required. The Momordica charantia (MC) extract has been shown to suppress cancer cell proliferation and invasion; however, the effect of the MC extract on [...] Read more.
Melanomas, which develop on malignant transformations of melanocytes, are highly malignant and prone to metastasis; therefore, effective drugs are required. The Momordica charantia (MC) extract has been shown to suppress cancer cell proliferation and invasion; however, the effect of the MC extract on melanoma in living organisms remains unclear. In this study, we investigated the mechanism underlying the amelioration of melanoma cell extravasation into mouse lungs by the MC extract. Male C57BL/6j mice (aged 8 weeks) were injected with B16 melanoma cells (1 × 105 cells/mouse). Subsequently, they were orally administered the MC extract daily for 2 weeks; mouse lung samples were obtained on the final day and analyzed. The MC extract ameliorated melanoma proliferation and infiltration into the lungs caused by melanoma cell treatment. It also increased phosphatase and tensin homolog deletion from chromosome 10 and suppressed paired box gene 3 (PAX3) and the phosphatidylinositol trisphosphate/RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin complex 1 signaling. Furthermore, it decreased microphthalmia-associated transcription factors and induced the suppression of cyclin-dependent kinase 2, hepatocyte growth factor receptor, B-cell/CLL lymphoma 2, and Ras-related proteins. Our findings suggest that the MC extract suppresses tumor survival genes by regulating PAX3, thereby ameliorating melanoma proliferation and invasion. Full article
(This article belongs to the Special Issue Bioactive Compounds of Natural Origin)
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Figure 1
<p>Effects of <span class="html-italic">Momordica charantia</span> (MC) extract treatment on melanoma cell infiltration and proliferation in mouse lungs. At 2 weeks after study initiation, the lungs were macroscopically analyzed (<b>a</b>); the number of DOPA-positive cells was measured by DOPA staining (<b>b</b>,<b>c</b>). Values are expressed in terms of mean ± SD (<span class="html-italic">n</span> = 5 animals). ** <span class="html-italic">p</span> &lt; 0.01. Scale bar = 100 μm.</p>
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<p>Effects of MC extract treatment on paired box gene 3 (PAX3) expression in the lungs of melanoma-bearing mice. At 2 weeks after study initiation, PAX3 expression was observed. Values are expressed in terms of mean ± SD (<span class="html-italic">n</span> = 5 animals). Intensity was calculated from five random visual fields with a constant area by using the ImageJ software. ** <span class="html-italic">p</span> &lt; 0.01. Scale bar = 100 µm.</p>
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<p>Effects of MC extract treatment on phosphatase and tensin homolog deletion from chromosome 10 (PTEN), phosphoinositide 3-kinase (PI3K), and phosphatidylinositol trisphosphate (PIP3) levels in the lungs of melanoma-bearing mice. The PTEN (<b>a</b>), PI3K (<b>b</b>), and PIP3 (<b>c</b>) levels were analyzed. Values are expressed in terms of mean ± SD (<span class="html-italic">n</span> = 5 animals). Intensity was calculated from five random visual fields with a constant area by using the ImageJ software. PI3K and PIP3 were measured using enzyme-linked immunosorbent assay (ELISA) kits. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01. Scale bar = 100 μm.</p>
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<p>Effects of MC extract treatment on the signal transduction from RAC-alpha serine/threonine-protein kinase (Akt) to protein synthesis in the lungs of melanoma-bearing mice. The Akt (<b>a</b>), mTORC1 (<b>b</b>), rpS6 (<b>c</b>), S6K1 (<b>d</b>), Ki67 (<b>e</b>), and cyclin D (<b>f</b>) levels were analyzed. Values are expressed in terms of mean ± SD (<span class="html-italic">n</span> = 5 animals). Intensity was calculated from five random visual fields with a constant area by using the ImageJ software. Ki67 and cyclin D were measured using ELISA kits. Scale bar = 100 μm. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>Effects of MC extract treatment on the signal transduction from RAC-alpha serine/threonine-protein kinase (Akt) to protein synthesis in the lungs of melanoma-bearing mice. The Akt (<b>a</b>), mTORC1 (<b>b</b>), rpS6 (<b>c</b>), S6K1 (<b>d</b>), Ki67 (<b>e</b>), and cyclin D (<b>f</b>) levels were analyzed. Values are expressed in terms of mean ± SD (<span class="html-italic">n</span> = 5 animals). Intensity was calculated from five random visual fields with a constant area by using the ImageJ software. Ki67 and cyclin D were measured using ELISA kits. Scale bar = 100 μm. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>Effects of MC extract treatment on the expression levels of malignant tumor survival genes located downstream of microphthalmia-associated transcription factor (MITF) in the lungs of melanoma-bearing mice. The MITF (<b>a</b>,<b>b</b>), cyclin-dependent kinase 2 (CDK2) (<b>a</b>,<b>c</b>), hepatocyte growth factor receptor c-Met (<b>a</b>,<b>d</b>), B-cell/CLL lymphoma 2 (Bcl2) (<b>a</b>,<b>e</b>), and Ras-related protein (RAB27A) (<b>a</b>,<b>f</b>) levels were analyzed. Values are expressed in terms of mean ± SD (<span class="html-italic">n</span> = 5 animals). Intensity was calculated from five random visual fields with a constant area by using the ImageJ software. Scale bar = 100 μm. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>Mechanism underlying the inhibition of melanoma cell proliferation and invasion by the MC extract. PAX3 increases the activity of MITF and promotes the proliferation and invasion of melanoma by increasing CDK2, c-MET, Bcl2, and RAB27A. PAX3 also suppresses PTEN and activates signaling from PIP3 to AKT, mTORC1, and S6K1, which promotes melanoma proliferation. The MC extract improves melanoma by suppressing the MITF pathway and PIP3 pathway through the control of PAX3.</p>
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14 pages, 5122 KiB  
Article
A Lucknolide Derivative Induces Mitochondrial ROS-Mediated G2/M Arrest and Apoptotic Cell Death in B16F10 Mouse Melanoma Cells
by Jae Hyeop Lee, Byeoung-Kyu Choi, Minsoo Kim, Hee Jae Shin and Sun Joo Park
Mar. Drugs 2024, 22(12), 533; https://doi.org/10.3390/md22120533 - 28 Nov 2024
Viewed by 766
Abstract
Melanoma is an aggressive skin cancer with a high risk of cancer-related deaths, and inducing apoptosis in melanoma cells is a promising therapeutic strategy. This study investigates the anti-tumor potential of a novel lucknolide derivative LA-UC as a therapeutic candidate for melanoma. Lucknolide [...] Read more.
Melanoma is an aggressive skin cancer with a high risk of cancer-related deaths, and inducing apoptosis in melanoma cells is a promising therapeutic strategy. This study investigates the anti-tumor potential of a novel lucknolide derivative LA-UC as a therapeutic candidate for melanoma. Lucknolide A (LA), a tricyclic ketal-lactone metabolite isolated from marine-derived Streptomyces sp., was chemically modified by introducing a 10-undecenoyl group to synthesize LA-UC. LA-UC preferentially inhibited the proliferation of melanoma cells, including B16F10, while exerting minimal effects on normal melanocytes or other tumor cell types, indicating the selective action of LA-UC against melanoma cells. LA-UC decreased G2/M checkpoint proteins, including cyclin B1 and Cdc2, while activating caspase-3 and caspase-9, resulting in G2/M cell cycle arrest and inducing apoptotic cell death in B16F10 cells. The addition of a pan-caspase inhibitor confirmed the caspase-dependent mechanism of LA-UC-induced cell death. Additionally, LA-UC elevated mitochondrial ROS levels, leading to mitochondrial membrane disruption, upregulation of pro-apoptotic proteins, and DNA damage in melanoma cells. The ROS scavenger N-acetylcysteine reduced LA-UC-induced mitochondrial ROS accumulation, mitochondrial membrane disruption, DNA damage, and apoptosis. Collectively, these findings suggest that LA-UC induces G2/M cell cycle arrest and caspase-dependent apoptosis in B16F10 cells through excessive mitochondrial ROS generation, membrane impairment, and DNA damage, highlighting its potential as a promising therapeutic candidate for melanoma treatment. Full article
(This article belongs to the Special Issue Marine Natural Products as Anticancer Agents, 4th Edition)
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Figure 1
<p>Structures of lucknolide A (LA) and lucknolide derivative (LA-UC), and its synthesis scheme. (<b>A</b>) The structure of LA, a natural product isolated from the marine-derived <span class="html-italic">Streptomyces</span> sp. strain 151KO-065. (<b>B</b>) The structure and its synthesis scheme of LA-UC, a semi-synthetic derivative of LA, synthesized by introducing a 10-undecenoyl group through semi-synthesis.</p>
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<p>LA-UC suppresses the proliferation of B16F10 mouse melanoma cells. (<b>A</b>) Several tumor cell lines, including B16F10, A375, Hela, HepG2, MDA-MB231, PC3, and HEMa human primary melanocytes were treated with LA or LA-UC for 24 h, and the cell viability was assessed by MTT assay. (<b>B</b>) B16F10 and A375 cells were treated with various concentrations of LA-UC for 24 h. Results are presented as mean ± standard error of the mean (SEM) of triplicate independent experiments. * <span class="html-italic">p</span> &lt; 0.05, **, <sup>##</sup> <span class="html-italic">p</span> &lt; 0.01, and ***, <sup>###</sup> <span class="html-italic">p</span> &lt; 0.001, compared to vehicle DMSO control in B16F10 or A375 cells.</p>
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<p>LA-UC induces G2/M arrest and apoptosis in B16F10 mouse melanoma cells. (<b>A</b>) Representative cell cycle analysis images showing LA-UC-induced G2/M phase arrest. B16F10 cells were treated with indicated concentrations of LA-UC for 24 h, fixed with ethanol, stained with propidium iodide (PI), and then analyzed using flow cytometry. The black dot line is vehicle DMSO control, and the red line (filled) is LA-UC-treated cells (<b>B</b>) Representative fluorescence-activated cell sorting (FACS) images showing LA-UC-induced apoptosis. Cell death was calculated as Annexin V and/or PI-positive cells. Results were quantified and are presented as mean ± standard error of the mean (SEM) of triplicate independent experiments. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001, compared to the control.</p>
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<p>Representative western blot images indicating LA-UC-induced G2/M phase arrest (<b>A</b>) and caspase-dependent apoptosis (<b>B</b>,<b>C</b>). B16F10 cells were treated with indicated concentrations of LA-UC for 24 h. Cyclin B1, Cdc2, caspase-3 and 9, cleaved caspase-3 and 9, GAPDH, and actin expressions were analyzed via immunoblotting. Protein levels were normalized to GAPDH or actin, and the fold change was calculated by dividing the normalized expression levels of each sample by the control value. (<b>C</b>,<b>D</b>) Cells were treated with Z-VAD-FMK (20 μM) for 12 h and then additionally treated with 8 μM LA-UC for 24 h. (<b>C</b>) MTT assay was performed to determine cell viability, and activation of caspase-3 was detected via Western blot analysis (<b>D</b>). Results were quantified using Image J and are presented as mean ± standard error of the mean (SEM) of triplicate independent experiments. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001, compared to vehicle control. C-Cas3: cleaved caspase-3; C-Cas9: cleaved caspase-9.</p>
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<p>LA-UC induces an increase in mitochondrial ROS, loss of mitochondrial membrane potential, and DNA damage. (<b>A</b>) B16F10 cells were treated with 8 μM LA-UC or 15 μM CCCP, a mitochondrial uncoupler, for 12 h. The level of mitochondrial ROS was measured with MitoSOX<sup>TM</sup> staining, and DNA with Hoechst 33342 staining. Scale bar, 20 μm. (<b>B</b>) Levels of mitochondrial membrane potential were measured via JC-1 staining. Representative images are shown. The intensity ratio of the green-to-red fluorescence was determined. Data are presented as the mean ± standard error of the mean (SEM). (<b>C</b>) Cells were treated the same as in (<b>A</b>,<b>B</b>), and expression levels of Bak, Bim, and cytochrome C were detected. (<b>D</b>) γ-H2AX protein was visualized via immunofluorescence using its primary antibodies to detect DNA damage and also determined by western blotting. Scale bar, 20 μm. Results were quantified and are presented as mean ± SEM of triplicate independent experiments. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001, compared to control. Cyt C: Cytochrome C.</p>
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<p>LA-UC-induced excessive generation of mitochondrial ROS is associated with LA-UC-induced cell cycle arrest and apoptosis in B16F10 cells. (<b>A</b>–<b>C</b>) B16F10 cells were pre-incubated with 2 mM NAC for 12 h and then additionally treated with 8 μM LA-UC or 15 μM CCCP for 12 h. (<b>A</b>) MTT assay was performed to determine cell viability. (<b>B</b>) Mitochondrial ROS levels were measured by MitoSOX<sup>TM</sup> staining. Scale bar, 20 μm. (<b>C</b>) Mitochondrial membrane potential was evaluated by JC-1 staining. (<b>D</b>–<b>F</b>) Cells were treated the same as in (<b>A</b>–<b>C</b>), and cell lysates were analyzed by western blotting for endogenous proteins. Representative images are shown. The expression levels of proteins were normalized to GAPDH or actin, and then the fold change was calculated by dividing each sample’s value by the control value. Results are presented as mean ± standard error of the mean (SEM) of triplicate independent experiments. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001 compared to control. C-Cas3: cleaved caspase-3; Cyt C: cytochrome C.</p>
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36 pages, 37425 KiB  
Article
Cocaine-Induced DNA-Dependent Protein Kinase Relieves RNAP II Pausing by Promoting TRIM28 Phosphorylation and RNAP II Hyperphosphorylation to Enhance HIV Transcription
by Adhikarimayum Lakhikumar Sharma, Priya Tyagi, Meenata Khumallambam and Mudit Tyagi
Cells 2024, 13(23), 1950; https://doi.org/10.3390/cells13231950 - 23 Nov 2024
Viewed by 933
Abstract
Drug abuse continues to pose a significant challenge in HIV control efforts. In our investigation, we discovered that cocaine not only upregulates the expression of the DNA-dependent protein kinase (DNA-PK) but also augments DNA-PK activation by enhancing its phosphorylation at S2056. Moreover, DNA-PK [...] Read more.
Drug abuse continues to pose a significant challenge in HIV control efforts. In our investigation, we discovered that cocaine not only upregulates the expression of the DNA-dependent protein kinase (DNA-PK) but also augments DNA-PK activation by enhancing its phosphorylation at S2056. Moreover, DNA-PK phosphorylation triggers the higher localization of the DNA-PK into the nucleus. The finding that cocaine increases the nuclear localization of the DNA-PK provides further support to our observation of enhanced DNA-PK recruitment at the HIV long terminal repeat (LTR) following cocaine exposure. By activating and facilitating the nuclear localization of the DNA-PK, cocaine effectively orchestrates multiple stages of HIV transcription, thereby promoting HIV replication. Additionally, our study demonstrates that the cocaine-induced DNA-PK promotes the hyper-phosphorylation of the RNA polymerase II (RNAP II) carboxyl-terminal domain (CTD) at Ser5 and Ser2 sites, enhancing both the initiation and elongation phases, respectively, of HIV transcription. The cocaine-mediated enhancement of transcriptional initiation is supported by its activation of cyclin-dependent kinase 7 (CDK7). Additionally, the induction of transcriptional elongation is marked by higher LTR recruitment and the increased phosphorylation of CDK9, which indicates the stimulation of positive transcriptional elongation factor b (P-TEFb). We demonstrate for the first time that cocaine, through DNA-PK activation, promotes the specific phosphorylation of TRIM28 at serine 824 (p-TRIM28, S824). This modification converts TRIM28 from a transcriptional inhibitor to a transactivator for HIV transcription. Additionally, we observed that the phosphorylation of TRIM28 (p-TRIM28, S824) promotes the transition from the pausing phase to the elongation phase of HIV transcription, thereby facilitating the production of full-length HIV genomic transcripts. This finding corroborates the previously observed enhanced RNAP II CTD phosphorylation at Ser2, a marker of transcriptional elongation, following cocaine exposure. Accordingly, upon cocaine treatment, we observed the elevated recruitment of p-TRIM28-(S824) at the HIV LTR. Overall, our results unravel the intricate molecular mechanisms underlying cocaine-induced HIV transcription and gene expression. These findings hold promise for the development of highly targeted therapeutics aimed at mitigating the detrimental effects of cocaine in individuals living with HIV. Full article
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Figure 1
<p>Cocaine enhances both the catalytic activity and nuclear level of the DNA-PK. MT-4 (<b>A</b>) and microglial cells (<b>C</b>) were treated with different concentrations of cocaine (Coc: 5, 10, and 20 μM) for 3 h (Lanes 2 to 4). Jurkat-pHR’-P’-Luc cells were treated with 10 µM cocaine (Coc) in replicates for 30 min and 3 h (Lanes 3 to 6) (<b>E</b>). Cells were harvested, and nuclear lysates were analyzed by immunoblotting using specific antibodies, pDNA-PKcs (S2056) and the DNA-PKcs, as indicated. Actin, a constitutively expressed protein, was used as a loading control. Densitometric analysis of protein bands (normalized to actin) confirmed the significant upregulation of the total DNA-PKcs and its phosphorylated form, pDNA-PKcs S2056 (pDNA-PKcs), following cocaine treatment (<b>B</b>,<b>D</b>,<b>F</b>). Representative immunofluorescence images (<b>G</b>), show control (Ctrl) and cocaine-treated (Coc) cells probed with anti-DNA-PKcs (Green) or anti-pDNA-PKcs (2056) (Red) antibodies which are co-labeled with DAPI (blue) for nuclear visualization. Images were captured at 60× magnification; the scale bar represents 10 µM (<b>G</b>). In panel (<b>H</b>), the MT-4 cells were treated with increasing concentrations of cocaine for 3 h. Cells were harvested and lysed, and both cellular and nuclear lysates were analyzed by immunoblotting with antibodies against DNA-PKcs, HDAC1, and actin (<b>H</b>). Densitometric analysis of the cellular and nuclear DNA-PKcs upon cocaine treatment (<b>I</b>). Immunoblots shown are representative of at least three independent experiments. The results are expressed as the mean ± SD and were analyzed by one- or two-way ANOVA, followed by Tukey’s multiple comparison test. Asterisks over the bars indicate significant differences: * <span class="html-italic">p</span> &lt; 0.05 for the comparisons of cocaine-treated cells vs. untreated cells (Ctrl).</p>
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<p>Cocaine-induced HIV transcription augments overall HIV replication. The structure of the lentiviral vector (pHR’-PNL-Luc) carrying the reporter luciferase gene under the HIV LTR promoter (<b>A</b>). A schematic representation of the cocaine (Coc) treatment scheme to perform a luciferase reporter assay (<b>B</b>). Jurkat-pHR’-P-Luc cells were chronically treated with 5 µM–20 µM of cocaine. The cells were lysed, the protein was quantified, and an equal amount of protein was used in each sample to perform luciferase assays (<b>C</b>). A schematic depiction of the cocaine treatment and subsequent infection of PBMCs with replication-competent HIV (<b>D</b>). HIV transcripts were quantified by real-time PCR using primer sets that amplify the Envelope (Env) region of the HIV genome (<b>E</b>). The level of Gag/p24 protein was analyzed by immunoblotting with specific antibodies against HIV p24 (<b>F</b>). Actin, a constitutively expressed protein, was used as a loading control in the same blot. Densitometric analysis of protein bands (normalized to actin) confirmed a significant increase in p24 levels compared to untreated cells (Ctrl) (<b>G</b>). Immunoblots are representative of at least three independent experiments. The black bar in the graphical representation represents the control, while the red bar indicates the presence of the cocaine. The results are expressed as the mean ± SD, analyzed by one-way ANOVA followed by Tukey’s multiple comparison test (<b>C</b>,<b>E</b>) or unpaired <span class="html-italic">t</span>-test (<b>G</b>). Asterisks over the bars indicate significant differences: * <span class="html-italic">p</span> &lt; 0.05 for the comparison of cocaine-treated cells vs. untreated control cells.</p>
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<p>Partial DNA-PK inhibition severely impairs HIV transcription and latency reactivation. A schematic representation of the protocol for the luciferase reporter assay detailing treatment with the DNA-PK inhibitor (DNA-PKi), M3814, and TNF-α (<b>A</b>). Jurkat-pHR’-P-Luc cells were treated with 5, 10, 15, and 20 µM of M3814 for 24 h, followed by activation with TNF-α (10 ng/mL) for another 48 h. Cells were lysed, the cell extract was quantified, and an equal amount of protein per sample was used to perform luciferase assays (<b>B</b>). The equal amounts of the same lysates were analyzed by immunoblotting using specific antibodies against the luciferase protein (sc-74548) (<b>C</b>). Jurkat-pHR’-P-Luc cells were cultured with different concentrations (2 μM to 40 μM) of M3814 for 48–72 h, and cell cytotoxicity was determined via MTS-PMS cell proliferation assay (Promega, Madison, WI, USA) (<b>D</b>). Latently infected 2D10 cells, which express a short-lived green fluorescent protein (d2EGFP) under the control of the HIV LTR promoter, were treated with 5 µM or 10 µM of M3814 for 24 h. Later, cells were stimulated with TNF-α for an additional 48 h. GFP expression was then assessed using flow cytometry (<b>E</b>,<b>F</b>). Immunoblots shown are representative of at least three independent experiments. In the graph, the black bar represents control, the gray bar denotes the absence of TNF-α, the red bar shows the presence of TNF-α alone, and fading red colors indicate dose-dependent inhibition of HIV by the inhibitor in presence of TNF-α. The results are expressed as the mean ± SD and analyzed by one- or two-way ANOVA followed by Tukey’s multiple comparison test. “ns” indicates not significant. Asterisks over the bars indicate significant differences: ** <span class="html-italic">p</span> &lt; 0.01 and *** <span class="html-italic">p</span> &lt; 0.001 for the comparison of either inactive vs. activated cells (TNF-α) or activated cells (TNF-α) vs. activated cells (TNF-α) treated with the DNA-PKi, M3814.</p>
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<p>Partial DNA-PK inhibition restricts HIV replication. A schematic representation of the treatment schedule of cells with DNA-PK inhibitors (M3814, NU7441), and/or TNF-α in the presence of HIV infection (<b>A</b>). Jurkat cells were treated overnight with either different concentrations of M3814 (5, 10, 15, and 20 μM) (<b>B</b>) or NU7441 (5, 10, 15, and 20 µM) (<b>D</b>) (Lanes 5–12). The next day, cells were activated with 10 ng/mL TNF-α for 3 h (Lanes 3, 4, 6, 8, 10, and 12). Subsequently, cells were infected with replication-competent dual-tropic HIV (Type 1 strain 93/TH/051) (Lanes 1–12). Cell lysates were prepared 4 h (NU7441) or 6 h (M3814) post-infection (hpi). The cell lysates were quantified, and equal amounts were analyzed per sample via immunoblotting using specific antibodies against HIV gag/p24 protein, as indicated (<b>B</b>,<b>D</b>). Immunoreactive proteins were detected using appropriately labeled secondary antibodies with Licor. Actin was used as a loading control. Densitometric analysis of protein bands relative to actin (<b>C</b>,<b>E</b>). Immunoblots are representative of at least three independent experiments. In the graph, the black bar represents control, the gray bar denotes the absence of TNF-α, the red bar shows the presence of TNF-α alone, and fading red colors indicate dose-dependent inhibition of HIV by the inhibitor in presence of TNF-α. The results are expressed as the mean ± SD and analyzed by one-way ANOVA followed by Tukey’s multiple comparison test. Asterisks over the bars indicate significant differences: ** <span class="html-italic">p</span> &lt; 0.01 for the comparison of inactive vs. activated cells (TNF-α) and activated cells (TNF-α) vs. activated cells (TNF-α) treated with DNA-PK inhibitors, NU7441 or M3814.</p>
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<p>Cocaine-mediated DNA-PK activation promotes HIV transcription and replication in both cell lines and primary cells. Jurkat-pHR’-P-Luc cells were treated with 10 µM of M3814 for 24 h. The next day, cells were treated with cocaine twice daily for 48 h and again for 3 h before harvesting. Cells were lysed, quantified protein amount, and the level of reporter protein expression was determined using a luciferase reporter assay (<b>A</b>). Jurkat cells (<b>B</b>,<b>C</b>) and PBMCs (<b>D</b>,<b>E</b>) were treated with 10 µM of M3814 for 24 h, then treated with cocaine for 3 h, and subsequently infected with replication-competent HIV for another 3 to 6 h. HIV transcripts were quantified by real-time PCR using primer sets that amplify the Nuc-2 (<b>B</b>,<b>D</b>) and Env (<b>C</b>,<b>E</b>) regions of the HIV genome. In panel (<b>F</b>), Jurkat cells were treated with 10 µM of M3814 for 24 h (Lanes 7 to 12), then treated with cocaine for 3 h (Lanes 3–6 and 10–12), and infected with replication-competent HIV across all lanes (Lanes 1–12) for another 5 h. The levels of HIV p24 and p17 proteins were analyzed via immunoblotting using antibodies against those proteins (<b>F</b>). Actin, a constitutively expressed protein, was used as a loading control. Densitometric analysis of protein bands (normalized to actin) was performed (<b>G</b>). Immunoblots are representative of at least three independent experiments. In the graph, the black bar represents the control, the red bar indicates the presence of cocaine, and the fading red colors show the effect of the inhibitor, with or without cocaine. The results are expressed as the mean ± SD and analyzed by two-way ANOVA followed by Tukey’s multiple comparisons test. Asterisks over the bars indicate significant differences: * <span class="html-italic">p</span> &lt; 0.05 for the comparison of cocaine-treated samples vs. untreated (Ctrl) and the comparison of cocaine plus inhibitor-treated samples vs. cocaine alone-treated samples.</p>
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<p>Cocaine promotes HIV transcription by enhancing the phosphorylation of the C-terminal domain (CTD) of RNA polymerase II (RNAP II). THP-1 cells were treated with increasing doses of cocaine (5, 10, 15, and 20 µM) for 3 h (<b>A</b>). MT-4 cells were treated as follows: untreated and uninfected (Lane 1), infected with HIV (93/TH/051) without cocaine treatment (Lane 2), treated with cocaine without HIV infection (Lane 3), or pre-treated with different concentrations of cocaine before HIV infection (Lanes 4 to 6) (<b>C</b>). Cells were harvested, and nuclear lysates were analyzed by immunoblotting with specific antibodies against phosphorylated RNAP II, RNAP II Ser2, and RNAP II Ser5. Actin, a constitutively expressed protein, was used as the loading control. Densitometric analysis of protein bands (normalized to actin) confirmed the significant hyper-phosphorylation of the RNAP II CTD within both Ser2 and Ser5 residues following cocaine treatment (<b>B</b>,<b>D</b>). THP-1 cells were treated with cocaine in the absence or presence of different concentrations of M3814 (0.5, 5, and 10 µM) (<b>E</b>). Cells were harvested, and nuclear extracts were evaluated via immunoblotting using specific antibodies against RNAP II Ser2, RNAP II Ser5, and total RNAP II. Densitometric analysis of protein bands (normalized to actin) (<b>F</b>). Immunoblots are representative of at least three independent experiments. The results are expressed as the mean ± SD and analyzed by two-way ANOVA followed by Tukey’s multiple comparison test. “ns” indicates not significant. Asterisks over the bars indicate significant differences. * <span class="html-italic">p</span> &lt; 0.05 is for the comparison of cocaine-treated samples against untreated (Ctrl) and the comparison of cocaine plus inhibitors treated against cocaine-alone-treated samples.</p>
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<p>Cocaine enhances the elongation phase of HIV transcription, not only by stimulating the DNA-PK, but also P-TEFb. Jurkat-pHR’P-Luc cells were treated with increasing doses of cocaine (5, 10, 15, 20, and 25 µM) for 3 h (<b>A</b>). Jurkat-pHR’P-Luc cells were treated as follows: untreated and uninfected (Lane 1), infected with HIV (93/TH/051) without cocaine treatment (Lane 2), treated with cocaine without HIV infection (Lane 3), or pre-treated with different concentrations of cocaine before HIV infection (Lanes 4 to 6) (<b>C</b>). Cells were harvested, and nuclear lysates were analyzed by immunoblotting with specific antibodies against P-TEFb subunits CDK9 and Cyclin T1, as well as CDK7 (TFIIH). Actin was used as a loading control. Densitometric analysis of protein bands (normalized to actin) confirmed a significant increase in CDK7, Cyclin T1, and p-CDK9 (Thr186) compared to untreated (Ctrl) cells (<b>B</b>,<b>D</b>). Wild-type (WT) and DNA-PK knockdown (DNA-PK KD) cells were treated with cocaine for 30 min and 3 h, and nuclear extracts were subjected to immunoblotting (<b>E</b>). Densitometric analysis of protein bands (normalized to actin) showed increased p-CDK9 phosphorylation and CDK7 activation in WT cells upon cocaine exposure (<b>F</b>). However, in DNA-PK KD cells, the lack of p-CDK9 (Thr186) phosphorylation and CDK7 activation upon cocaine treatment demonstrated that cocaine-induced activations are DNA-PK-specific (<b>F</b>). Immunoblots are representative of at least three independent experiments. The results are expressed as the mean ± SD for three independent experiments, analyzed by two-way ANOVA followed by Tukey’s multiple comparisons test. “ns” indicates not significant. Asterisks over the bars indicate significant differences: * <span class="html-italic">p</span> &lt; 0.05 compared to untreated cells (Ctrl).</p>
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<p>The cocaine-induced DNA-PK relieves RNAP II pausing by phosphorylating TRIM28 at S824. THP-1 (<b>A</b>,<b>B</b>) and Jurkat cells (<b>C</b>,<b>D</b>) were treated with increasing doses of cocaine, and the nuclear lysates were quantified and then evaluated via immunoblotting using specific antibodies against pTRIM28 (S824) and total TRIM28. Densitometric analysis confirmed a significant increase in pTRIM28 (S824) levels compared to untreated cells (Ctrl) (<b>A</b>–<b>D</b>). Jurkat-pHR’P-Luc cells were treated with cocaine (10 µM) for varying durations (30 min, 3 h, and 6 h), and the nuclear lysates were analyzed via immunoblotting using specific antibodies against pTRIM28 (S824) and total TRIM28. Densitometric analysis of protein bands (normalized to actin) confirmed a significant increase in pTRIM28 (S824) levels compared to untreated cells (Ctrl) (<b>E</b>,<b>F</b>). THP-1 cells were treated as follows: untreated and uninfected (Lane 1), infected with HIV (93/TH/051) without cocaine (Lane 2), treated with cocaine without HIV infection (Lane 3), or pre-treated with different concentrations of cocaine before HIV infection (Lanes 4 to 6). Nuclear lysates were analyzed via immunoblotting using specific antibodies against pTRIM28 (S824) and total TRIM28 (<b>G</b>). Densitometric analysis of protein bands (normalized to actin) confirmed a significant increase in pTRIM28 (S824) levels compared to untreated cells (Ctrl) (<b>H</b>). THP-1 cells were treated with different concentrations of M3814 in the presence and absence of cocaine (10 µM), and the nuclear lysates were analyzed via immunoblotting using specific antibodies against pTRIM28 (S824) and total TRIM28 (<b>I</b>). Densitometric analysis of protein bands (normalized to actin) (<b>J</b>). WT and DNA-PK KD cells were treated with cocaine for 30 min and 3 h, and the nuclear lysates were subjected to immunoblotting (<b>K</b>). Densitometric analysis of protein bands (normalized to actin) (<b>L</b>). Immunoblots are representative of at least three independent experiments. The results are expressed as the mean ± SD for three independent experiments, analyzed by two-way ANOVA followed by Tukey’s multiple comparisons test. “ns” indicates not significant. Asterisks over the bars indicate significant differences. * <span class="html-italic">p</span> &lt; 0.05 is for the comparison of cocaine-treated samples against untreated (Ctrl) and the comparison of cocaine plus inhibitors treated against cocaine alone-treated samples.</p>
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<p>Cocaine promotes RNAP II pause release by phosphorylating TRIM28 at S824. Jurkat cells were exposed to increasing concentrations of cocaine, and both cytoplasmic and nuclear extracts were subjected to immunoblotting using specific antibodies against pTRIM28 (S824), total TRIM28, DSIF (SPT-5), NELF-E, and HDAC1 (<b>A</b>). Densitometric analysis of protein bands (normalized to actin) (<b>B</b>,<b>C</b>). Immunoblots are representative of at least three independent experiments. The results are expressed as the mean ± SD for three independent experiments, analyzed by two-way ANOVA followed by Tukey’s multiple comparisons test. “ns” indicates not significant. Asterisks over the bars indicate significant differences. Statistical significance is set as <span class="html-italic">p</span> &lt; 0.05 (*) compared to untreated cells (Ctrl).</p>
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<p>Cocaine enhances HIV transcription by promoting the recruitment of the DNA-PKcs and pTRIM28 (S824) at the HIV LTR. Jurkat cells freshly infected with replication-incompetent HIV and pHR’P-Luc were exposed to cocaine. Chromatin immunoprecipitation (ChIP) assays were conducted to assess the recruitment kinetics of the DNA-PKcs, RNAP II, CDK7 (TFIIH), pTRIM28 (S824), total CDK9, and H3K27me3 at the promoter (<b>A</b>,<b>E</b>), Nucleosome-1 (<b>B</b>,<b>F</b>), Nucleosome-2 (<b>C</b>,<b>G</b>), and the further downstream Envelope regions (<b>D</b>,<b>H</b>) of the HIV LTR, using specific primer sets. The results are presented as the mean ± SD for three independent experiments, analyzed by two-way ANOVA followed by Tukey’s multiple comparisons test. “ns” indicates not significant. Asterisks above the bars indicate significant differences. Statistical significance is set as <span class="html-italic">p</span> &lt; 0.05 (*) compared to untreated cells (Ctrl).</p>
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<p>Cocaine-mediated DNA-PK activation enhances multiple aspects of HIV transcription. Cocaine-induced DNA-PK activation facilitates various stages of HIV transcription. Firstly, it enhances the initiation phase of HIV transcription by phosphorylating the C-terminal domain (CTD) of RNA polymerase II (RNAP II) at Ser5. Secondly, the cocaine-stimulated DNA-PK promotes the elongation phase by both directly catalyzing and facilitating the recruitment of positive transcription elongation factor b (P-TEFb), leading to the phosphorylation of Ser2 within the RNAP II CTD. This posttranslational modification renders RNAP II processive, ensuring efficient elongation. Finally, cocaine-induced DNA-PK activity also alleviates RNAP II pausing by phosphorylating TRIM28 at Ser824 (p-TRIM28 S824). This modification transforms TRIM28 from a transcriptional pausing factor to a facilitator (transactivator), thereby supporting HIV transcription.</p>
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