Bcl-2、Bak及caspase-9、3在维生素E琥珀酸酯诱导人胃癌细胞凋亡中的作用

目的探讨维生素E琥珀酸酯(VES)对体外培养的人胃癌细胞株SGC-7901细胞的凋亡诱导作用及其可能机制。方法以体外培养的人胃癌SGC-7901细胞为肿瘤模型,给予不同浓度水平的VES处理不同时间后,采用四甲偶氮唑盐比色(MTT)法观察VES对人胃癌细胞的生长抑制作用;用Annexin-V-FITC方法检测VES对胃癌细胞的凋亡诱导作用;采用Western blotting方法检测VES处理后的胃癌细胞中Bcl-2和Bak蛋白表达及caspase-9、caspase-3酶原的表达。结果(12.5～50.0)μmol/L的VES作用于人胃癌细胞24h后就可以抑制胃癌细胞的生长,呈明显的剂量依赖关系;Annexin-V-FITC和PI双染流式细胞仪检测结果表明,50μmol/LVES处理SGC-7901细胞12h后即可以引起细胞凋亡,且随作用时间的延长凋亡越明显。Western blotting结果显示,VES可以调节胃癌细胞中与凋亡相关的Bcl-2和Bak蛋白的表达,同时促进caspase-9、caspase-3酶原的裂解与活化。结论调节Bcl-2和Bak蛋白的表达,并裂解caspase-9、caspase-3是VES在体外发挥对人胃癌细胞的生长抑制和凋亡诱导作用的可能机制之一。

Effects of Bcl-2, Bak, caspase-9, 3 in Vitamin E Succinate Induced Apoptosis of Human Gastric Carcinoma Cells

Objective To study the growth inhibition and apoptosis-inducing effects of vitamin E succinate(VES) in human gastric carcinoma cells in vitro. Methods Cultured human gastric carcinoma cells were used as tumor model. MTT method was applied to detect the growth inhibition effect of VES in human gastric cancer cells. Apoptosis induced by VES treatment was detected by using Annexin-V-FITC assay. Protein expressions of Bcl-2, Bak, caspase-9 and caspase-3 were explored by Western blotting method. Results Treatment with 12.5~50 μmol/L VES for 24 h inhibited human gastric carcinoma SGC-7901 cells growth in a dose-dependent manner. The results of Annexin-V-FITC indicated that 50 μmol/L VES treatment for 12 h induced apoptosis in gastric cancer cell in a time-dependent manner. Besides, the regulation effects of VES on the protein expression of Bcl-2 and Bak with the cleavage and activation of caspase-9 and caspase-3 were proved by Western blotting assay. Conclusion VES inhibited human gastric carcinoma SGC-7901 cells growth and induced apoptosis with the regulation of Bcl-2, Bak protein expression and cleavage of caspase-9 and caspase-3.