白扁豆多糖对人胃癌细胞凋亡的作用及其机制

Effect of white lentil polysaccharides on the apoptosis of human gastric cancer cells and its mechanism

目的:探讨白扁豆多糖对人胃癌细胞凋亡的作用及其相关机制。方法:胃癌细胞HGC-27和SGC-7901经终浓度为16、8、4、2、1和0μg/ml的白扁豆多糖作用24、48和72h,各设3个复孔。MTS法检测其增殖活性;分别取经4、0μg/ml白扁豆多糖作用24h的HGC-27和SGC-7901细胞(各3个复孔),JC-1染色观察线粒体膜电位,流式细胞仪分析细胞周期和凋亡率,QPCR法探讨Bcl-2、caspase-3和Bax基因的mRNA转录水平。结果:白扁豆多糖作用后,HGC-27和SGC-7901细胞线粒体膜电位降低;细胞增殖显著受抑制(P<0.01),且效果与药物作用浓度和时间有关;细胞凋亡率分别为53.15%和38.77%,均较PBS处理组(8.07%和6.03%)明显增加(P<0.01),而细胞周期无显著变化;同时,细胞内Bcl-2基因的转录水平明显受抑制,Bax和caspase-3基因的转录明显上调(P<0.01)。结论:白扁豆多糖可通过调节Bax-Bcl-2-caspase3通路,诱导胃癌细胞HGC-27和SGC-7901凋亡。

Objective： To investigate the effect of white lentil polysaccharides on the apoptosis of human gastric cancer cells and its related mechanism. Methods： Gastric cancer cell lines HGC-27 and SGC-7901 were treated with 16,8,4,2,1 and 0 μg/ml white lentil polysaccharides for 24,48 and 72 hours respectively,each experiment 3 wells. The proliferation activities of gastric cancer cells were detected with Cell Titer 96-？AQueous Non-Radioactive Cell Proliferation Assay（ MTS）. HGC-27 and SGC-7901 cells were treated with 0 or 4 μg/ml white lentil polysaccharides for 24 hours respectively,each experiment 3 wells,then the changes of cell mitochondrial membrane potential were observed by JC-1 staining,cell cycle and cell apoptosis rates were evaluated with flow cytometry,the levels of mRNA expression of Bcl-2,caspase-3 and Bax genes were investigated with real-time quantitative PCR detecting system（ QPCR）. Results： After the gastric cancer cell lines HGC-27 and SGC-7901 were treated with white lentil polysaccharides,the mitochondrial membrane potential of the cells was significantly reduced,proliferation activities of the cells were inhibited obviously（ P 0.01）,and the inhibition degree was related with drug concentration and incubation time. Flow cytometry analysis showed that the apoptosis rates of HGC-27 and SGC-7901 cell lines were 53. 15% and 38. 77% respectively,which were significantly increased compared with PBS treatment groups（ 8. 07% and 6. 03%,P 0. 01）. And the cell cycle of these cells was not influenced significantly. The results of QPCR showed that Bcl-2 gene transcription level of HGC-27 and SGC-7901 cell lines was significantly down-regulated,and the transcription levels of Bax and caspase-3 genes were significantly increased（ P 0. 01）. Conclusion： The white lentil polysaccharides can induce the apoptosis of gastric cancer cells lines HGC-27 and SGC-7901,and the mechanism of their apoptosis may be mediated by the regulation of Bax-Bcl-2-caspase3 pathway.