丙戊酸钠诱导肝癌细胞HepG2凋亡及其机制探讨

Effects and mechanisms of VPA on cell apoptosis in the human hepotoma cell-HepG2

目的观察丙戊酸钠对肝癌细胞系HepG2的诱导凋亡作用并通过检测Caspase3、Caspase8、Caspase9的活性及蛋白表达探讨其诱导凋亡的机制。方法经0．75～4．0mmol／L丙戊酸钠诱导后，流式细胞仪Annexin V／PI双标法分析细胞凋亡的变化；分光光度法检测Caspase3、Caspase8、Caspase9活性；流式细胞仪间接免疫荧光法定量分析Caspase3、Caspase8、Caspase9蛋白表达。结杲丙戊酸钠可明显诱导HepG2细胞凋亡，并且此作用呈时间、剂量依赖趋势；经过丙戊酸钠诱导，Caspase3、Caspase9活性及蛋白表达被上调，较对照组明显升高（P〈0．001），Caspase8活性及蛋白表达未见明显改变（P〉0．05）。结论丙戊酸钠可明显诱导HepG2肝癌细胞凋亡，此作用通过激活内源性凋亡途径实现。

Objective To investigate the effects of Valproate acid sodium（VPA）, a selective inhibitor of HDACs, on cell apoptosis of the human hepotoma cell -HepG2 and study the probable mechanisms. Methods The apoptosis rate was determined by FCM with Annexin V/PI staining. The activities and protein expressions of Caspase3, Caspase8 and Caspase9 were determined by spectrophotometry and indirect immunofluorescence techniques. Results After treatment with different concentrations of VPA, the apoptosis rate of human hepotoma cells significantly increased in a time- and dose-dependent manner. The activities and protein expressions of Caspase3 and Caspase9 were up-regulated in the exper- imental group compared with the control group （ P 〈 0.001 ）. On the other hand, both the activity and the protein expression of Caspase8 were not significantly different between the experimental group and the control group （ P 〉 0.05）. Conclusion VPA can effectively induce HepG2 cell apoptosis by activating the intrinsic apoptosis pathway.