Objective： The aim of this study was to explore the mechanisms by which the flavonoid casticin enhances tumor necrosis factor-related apoptosis-inducing ligand （TRAIL）-induced apoptosis in colon cancer cells. Meth...Objective： The aim of this study was to explore the mechanisms by which the flavonoid casticin enhances tumor necrosis factor-related apoptosis-inducing ligand （TRAIL）-induced apoptosis in colon cancer cells. Methods： Human colon cancer HT-29 cells were treated with TRAIL or casticin. Cytotoxicity was examined by MTT assay, and apoptosis determined by morphological observation and flow cytometric analysis. Death receptor 5 （DRS）, DR4, and endoplasmic reticulum （ER） stress response markers, including glucose regulating protein 78 （GRP78）, activating transcription factor 4 （ATF4） and CHOP （CCAAT/enhancer binding protein homologous protein）, were examined with western blot. Small interfering RNA （siRNA） transfection was employed to knock down CHOP. Results： HT-29 cells were resistance to TRAIL-induced apoptosis, but casticin, at subtoxic concentrations, potentiated HT-29 cells to TRAIL-induced apoptosis. Casticin up-regulated the expression of DR5 time-and dose-dependent manners, but had no effect on the expression of DR4. Also, casticin increased the levels of ER stress response markers （GRP78, ATF4 and CHOP） in a similar way to DR5. Knockdown of CHOP by specific siRNA, or salubrinal, an ER stress inhibitor, abolished the up-regulation of DR5 and enhancement of TRAIL-induced apoptosis by casticin. Conclusion： Casticin enhances TRAIL-induced apoptosis of colon cancer cells by ER stress-mediated up-regulation of DR5.展开更多
Polygonum cuspidatum is used as a traditional medicinal herb for the therapy of various diseases including several types of cancers. In the present study, we focused on addressing the anti-cancer activity and molecula...Polygonum cuspidatum is used as a traditional medicinal herb for the therapy of various diseases including several types of cancers. In the present study, we focused on addressing the anti-cancer activity and molecular mechanism of methanol extract of Polygonum cuspidatum (MEPC) in HSC-2 human oral cancer cells. The effect of MEPC on oral cancer cells was estimated by 3-(4,5-dimethylthiazol-20yl)-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay, 4’-6-diamidino-2-phenylindole (DAPI) staining and Western blot analysis. MEPC inhibited the cell viability and induced apoptosis through the induction of death receptor (DR) 5. MEPC also increased the expression of C/EBP homologous protein/growth arrest and the DNA damage-inducible gene 153 (CHOP), a transcription factor induced by ER stress. Thus, we concluded that the induction of CHOP leading to DR5 up-regulation is required for the anti-cancer activity of MEPC in HSC-2 cells and MEPC may be a promising drug candidate for oral cancer.展开更多
Objective： To investigate the effects of xanthotoxin from Apiaceae medicinal plants on cell proliferation and apoptosis, and explore its mechanism of action against human gastric carcinoma SGC-7901 cells in vitro.Met...Objective： To investigate the effects of xanthotoxin from Apiaceae medicinal plants on cell proliferation and apoptosis, and explore its mechanism of action against human gastric carcinoma SGC-7901 cells in vitro.Methods： SGC-7901, HepG-2, MCF-7, and A549 cells were treated with different concentrations of xanthotoxin（10, 20, 60, 80, 100, 120, 140, and 160 μg/mL） for 48 h, and the cell viability（IC50） was determined by MTT assay; Xanthotoxin-induced apoptosis in cells was observed by using Hoechst 33258 Staining Kit and Annexin V-FITC Apoptosis Detection Kit; Flow cytometry was used to detect apoptosis related proteins of Fas/FasL, Bid, and DR5/TRAIL proteins in human gastric carcinoma SGC-7901 cells after being treated by xanthotoxin; The influence of xanthotoxin on Caspase-8 protein expression in the cells was determined by Flouormetric Assay Kit.Results： Xanthotoxin obviously inhibited SGC-7901, HepG-2, MCF-7, and A549 cells proliferation, and its inhibition was in a concentration-dependent manner; flow cytometry results showed that in a certain concentration range, xanthotoxin can increase the expression levels of Fas/FasL and DR5/TRAIL proteins in a concentration-dependence manner. The content of Bid protein in cells was increased, and it showed concentration-dependence.Conclusion： Xanthotoxin may induce SGC-7901 cells apoptosis in a certain concentration range through the Fas/FasL protein mediated death receptor pathway, or by DR5/TRAIL mediated death receptor pathway, and increase the expression level of death receptor protein, activation Caspase-8, activating downstream effect factor, inducing cell apoptosis, or activate Caspase-8 cutting activate protein Bid, and then enter the mitochondrial pathway, induction of apoptosis.展开更多
文摘Objective： The aim of this study was to explore the mechanisms by which the flavonoid casticin enhances tumor necrosis factor-related apoptosis-inducing ligand （TRAIL）-induced apoptosis in colon cancer cells. Methods： Human colon cancer HT-29 cells were treated with TRAIL or casticin. Cytotoxicity was examined by MTT assay, and apoptosis determined by morphological observation and flow cytometric analysis. Death receptor 5 （DRS）, DR4, and endoplasmic reticulum （ER） stress response markers, including glucose regulating protein 78 （GRP78）, activating transcription factor 4 （ATF4） and CHOP （CCAAT/enhancer binding protein homologous protein）, were examined with western blot. Small interfering RNA （siRNA） transfection was employed to knock down CHOP. Results： HT-29 cells were resistance to TRAIL-induced apoptosis, but casticin, at subtoxic concentrations, potentiated HT-29 cells to TRAIL-induced apoptosis. Casticin up-regulated the expression of DR5 time-and dose-dependent manners, but had no effect on the expression of DR4. Also, casticin increased the levels of ER stress response markers （GRP78, ATF4 and CHOP） in a similar way to DR5. Knockdown of CHOP by specific siRNA, or salubrinal, an ER stress inhibitor, abolished the up-regulation of DR5 and enhancement of TRAIL-induced apoptosis by casticin. Conclusion： Casticin enhances TRAIL-induced apoptosis of colon cancer cells by ER stress-mediated up-regulation of DR5.
文摘Polygonum cuspidatum is used as a traditional medicinal herb for the therapy of various diseases including several types of cancers. In the present study, we focused on addressing the anti-cancer activity and molecular mechanism of methanol extract of Polygonum cuspidatum (MEPC) in HSC-2 human oral cancer cells. The effect of MEPC on oral cancer cells was estimated by 3-(4,5-dimethylthiazol-20yl)-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay, 4’-6-diamidino-2-phenylindole (DAPI) staining and Western blot analysis. MEPC inhibited the cell viability and induced apoptosis through the induction of death receptor (DR) 5. MEPC also increased the expression of C/EBP homologous protein/growth arrest and the DNA damage-inducible gene 153 (CHOP), a transcription factor induced by ER stress. Thus, we concluded that the induction of CHOP leading to DR5 up-regulation is required for the anti-cancer activity of MEPC in HSC-2 cells and MEPC may be a promising drug candidate for oral cancer.
基金supported by Harbin University of Commerce Research Funding(17x072)
文摘Objective： To investigate the effects of xanthotoxin from Apiaceae medicinal plants on cell proliferation and apoptosis, and explore its mechanism of action against human gastric carcinoma SGC-7901 cells in vitro.Methods： SGC-7901, HepG-2, MCF-7, and A549 cells were treated with different concentrations of xanthotoxin（10, 20, 60, 80, 100, 120, 140, and 160 μg/mL） for 48 h, and the cell viability（IC50） was determined by MTT assay; Xanthotoxin-induced apoptosis in cells was observed by using Hoechst 33258 Staining Kit and Annexin V-FITC Apoptosis Detection Kit; Flow cytometry was used to detect apoptosis related proteins of Fas/FasL, Bid, and DR5/TRAIL proteins in human gastric carcinoma SGC-7901 cells after being treated by xanthotoxin; The influence of xanthotoxin on Caspase-8 protein expression in the cells was determined by Flouormetric Assay Kit.Results： Xanthotoxin obviously inhibited SGC-7901, HepG-2, MCF-7, and A549 cells proliferation, and its inhibition was in a concentration-dependent manner; flow cytometry results showed that in a certain concentration range, xanthotoxin can increase the expression levels of Fas/FasL and DR5/TRAIL proteins in a concentration-dependence manner. The content of Bid protein in cells was increased, and it showed concentration-dependence.Conclusion： Xanthotoxin may induce SGC-7901 cells apoptosis in a certain concentration range through the Fas/FasL protein mediated death receptor pathway, or by DR5/TRAIL mediated death receptor pathway, and increase the expression level of death receptor protein, activation Caspase-8, activating downstream effect factor, inducing cell apoptosis, or activate Caspase-8 cutting activate protein Bid, and then enter the mitochondrial pathway, induction of apoptosis.
