Objective Many Asian countries including China,Japan and Korea have very high incidence of gastric cancer,in which about 42% cases occur in China's Mainland.The precise targets and underlying mechanisms are not we...Objective Many Asian countries including China,Japan and Korea have very high incidence of gastric cancer,in which about 42% cases occur in China's Mainland.The precise targets and underlying mechanisms are not well understood.Our previous study revealed that Astragalus saponins(AST)showed promising effects on the suppression of the growth of HT-29 human colon cancer cells and tumor xenograft by inhibiting cell proliferation and promoting apoptosis.In the present study,we investigated the anti-carcinogenic effects of AST in AGS human gastric adenocarcinoma cells and attempted to elucidate the underlying mechanisms.Methods Growth inhibition of AGS cells was determined by using the MTT viability test.Involvement of different members of the apoptotic cascade and other growth-related factors was explored by assessment of their protein expression using Western blot analysis.Distribution of cells in different phases of the cell cycle was assessed by flow cytometry.Results Our data indicate that AST induced growth-inhibition and apoptosis in AGS cells by activating caspase 3 with subsequent poly(ADP-ribose)polymerase(PARP)cleavage.Cell cycle arrest at the G2/M phase had been observed in AST-treated AGS cells.The anti-proliferative effect of AST was associated with modulation of cyclin B1 and p21.We then demonstrate that AST could downregulate the expression of VEGF,of which interaction with its receptors is important for angiogenesis during tumor formation.Conclusions Our findings suggest that AST is an effective agent in gastric cancer treatment by inducing cell cycle arrest and apoptosis,of which anti-angiogenesis could be an alternative mode of action.展开更多
文摘Objective Many Asian countries including China,Japan and Korea have very high incidence of gastric cancer,in which about 42% cases occur in China's Mainland.The precise targets and underlying mechanisms are not well understood.Our previous study revealed that Astragalus saponins(AST)showed promising effects on the suppression of the growth of HT-29 human colon cancer cells and tumor xenograft by inhibiting cell proliferation and promoting apoptosis.In the present study,we investigated the anti-carcinogenic effects of AST in AGS human gastric adenocarcinoma cells and attempted to elucidate the underlying mechanisms.Methods Growth inhibition of AGS cells was determined by using the MTT viability test.Involvement of different members of the apoptotic cascade and other growth-related factors was explored by assessment of their protein expression using Western blot analysis.Distribution of cells in different phases of the cell cycle was assessed by flow cytometry.Results Our data indicate that AST induced growth-inhibition and apoptosis in AGS cells by activating caspase 3 with subsequent poly(ADP-ribose)polymerase(PARP)cleavage.Cell cycle arrest at the G2/M phase had been observed in AST-treated AGS cells.The anti-proliferative effect of AST was associated with modulation of cyclin B1 and p21.We then demonstrate that AST could downregulate the expression of VEGF,of which interaction with its receptors is important for angiogenesis during tumor formation.Conclusions Our findings suggest that AST is an effective agent in gastric cancer treatment by inducing cell cycle arrest and apoptosis,of which anti-angiogenesis could be an alternative mode of action.
