儿茶素单体EGCG诱导胃癌MGC-803细胞凋亡和不同浓度作用效果的比较

Induction of Apoptosis in Stomach Cancer MGC-803 Cell by EGCG and Comparison of Effects at Various EGCG Concentration

目的:探讨EGCG体外诱导胃癌MGC-803细胞凋亡的作用。方法:以不同浓度EGCG分别处理MGC-803细胞,用琼脂糖凝胶电泳、电镜、MTT法观察MGC-803细胞DNA带型、形态和抑制率的变化。结果:琼脂糖凝胶电泳呈典型的DNA“梯状带”,但高浓度的EGCG(1×10^(-3)mol/L)作用MGC-803细胞33小时后,电泳显示细胞坏死后模糊的DNA呈弥散的“膜状带”。电镜观察可见染色质凝集呈新月状附在核膜周边,细胞变成数个大小不等的由膜包裹的凋亡小体。MTT法测定1×10^(-3)mol/L、1×10^(-4)mol/L、1×10^(-5)mol/L、1×10^(-6)mol/L、1×10^(-7)mol/L EGCG对MGC-803细胞生长抑制率分别为68.39%、20.38%、20.30%、16.99%、13.22%。结论:EGCG有明显的诱导胃癌MGC-803细胞凋亡作用,高浓度的EGCG直接导致细胞坏死。

Objective:To study the effect of epillatechin-3-gallate (EGCG) on stomach cancer MGC-803 cell growth and apopto-sis. Methods:Changes in DNA fragmentation, morphology and growth inhibition were evaluated with gel electrophoresis, electron microscopy and MTT assay. Results: When human stomach MGC-803 cell exposed to EGCG at 1×10-4 mol/L and 1×10-5 mol/L for 33 hours, the apoptosis characterization in DNA laddering band was shown,but when at 1× 10-3 mol/ L, DNA fragmentation was a smear band. Under electron microscope, it was found that condensation of chromosome adjoined nuclear membrane like a new moon and cells changed into apoptosis bodies closed by membrane. When the cells were treated with EGCG at 1×10-3 mol/L, 1×10-4 mol/L,1× 10-5 mol/L,1×10-6 mol/L and 1×10-7 mol/L,their growth inhibi-tions by MTT assay were 68.39 % , 20.38% ,20.30 % . 16.99 % and 13.22% respectively. Conclusion: EGCG significantly induced apoptosis in stomach cancer MGC-803 cell,and high concentration EGCG directly led the cells to death.