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
Background Cardiovascular disease is a major cause of mortality and morbidity in patients with chronic kidney disease Macrophage death in advanced atherosclerosJs promotes necrosis and plaque destabilization. In vitro...Background Cardiovascular disease is a major cause of mortality and morbidity in patients with chronic kidney disease Macrophage death in advanced atherosclerosJs promotes necrosis and plaque destabilization. In vitro data from peritoneal macrophages show apoptosis triggered through endoplasmic reticulum （ER） stress caused by free cholesterol accumulation plays an important role. Here we used THP-1 cells differentiated by 100 ng/ml of phorbol 12-myristate 13-acetate （PMA） for five days as an in vitro model, to investigate if acetylated low-density lipoprotein （AcLDL） loading could also induce apoptosis and its underlying mechanisms. Methods Oil red O staining was used to examine the lipid droplets. Confocal microscopy was used to visualize the uptake of AcLDL. Hoechst 33258 stain and the caspase 3,7 assay were used to detect apoptosis. High performance liquid chromatography was used in the intracellular free cholesterol （FC） and cholesterol ester （CE） assay. Western blotting was used to demonstrate the protein level. Real-time PCR was used to detect the changes of mRNAs. ER free cholesterol was also assayed. Results Confocal microscopy showed THP-1 cells differentiated by 100 ng/ml of PMA for five days uptake more AcLDL than differentiated for two days. Hoechst 33258 stain showed AcLDL could induce apoptosis in THP-1 macrophages in a time and dose dependent manner. Exposure of THP-1 macrophages to 100 ug/ml of AcLDL for 24 hours resulted in a significant increase in caspase 3,7 activity, a significant increase in FC and CE mass of 1.5 and 2.4-fold, meanwhile, a significant increase in transcription factor C/EBP homologous protein and a decrease in Bcl-2 both in protein and mRNA levels were observed with an 8-fold rise of free cholesterol in the ER. Conclusion ER stress is involved in AcLDL induced apoptosJs in THP-1 macrophages with free cholesterol accumulation in the ER.展开更多
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This study was supported by the grants from the National Natural Science Foundation of China （No. 30700373） and the Royal Free Hospital Special Trustees Grant 115.
文摘Background Cardiovascular disease is a major cause of mortality and morbidity in patients with chronic kidney disease Macrophage death in advanced atherosclerosJs promotes necrosis and plaque destabilization. In vitro data from peritoneal macrophages show apoptosis triggered through endoplasmic reticulum （ER） stress caused by free cholesterol accumulation plays an important role. Here we used THP-1 cells differentiated by 100 ng/ml of phorbol 12-myristate 13-acetate （PMA） for five days as an in vitro model, to investigate if acetylated low-density lipoprotein （AcLDL） loading could also induce apoptosis and its underlying mechanisms. Methods Oil red O staining was used to examine the lipid droplets. Confocal microscopy was used to visualize the uptake of AcLDL. Hoechst 33258 stain and the caspase 3,7 assay were used to detect apoptosis. High performance liquid chromatography was used in the intracellular free cholesterol （FC） and cholesterol ester （CE） assay. Western blotting was used to demonstrate the protein level. Real-time PCR was used to detect the changes of mRNAs. ER free cholesterol was also assayed. Results Confocal microscopy showed THP-1 cells differentiated by 100 ng/ml of PMA for five days uptake more AcLDL than differentiated for two days. Hoechst 33258 stain showed AcLDL could induce apoptosis in THP-1 macrophages in a time and dose dependent manner. Exposure of THP-1 macrophages to 100 ug/ml of AcLDL for 24 hours resulted in a significant increase in caspase 3,7 activity, a significant increase in FC and CE mass of 1.5 and 2.4-fold, meanwhile, a significant increase in transcription factor C/EBP homologous protein and a decrease in Bcl-2 both in protein and mRNA levels were observed with an 8-fold rise of free cholesterol in the ER. Conclusion ER stress is involved in AcLDL induced apoptosJs in THP-1 macrophages with free cholesterol accumulation in the ER.
