丙基戊酸钠对宫颈癌细胞HeLa增殖的影响机制

The mechanisms of sodium valproate on cell proliferation inhibition in cervical cancer cell line HeLa.

目的:探讨组蛋白去乙酰化酶抑制剂(histone deacetylase inhibitor,HDACI)丙基戊酸钠(sodium valproate,VPA)影响宫颈癌细胞HeLa增殖的机制。方法:用MTT法检测不同浓度VPA对HeLa细胞增殖的影响;倒置相差显微镜观察药物作用后细胞形态的变化;流式细胞仪(FCM)分析不同浓度VPA对HeLa细胞凋亡及细胞周期的影响;Western blot观察不同浓度VPA处理后caspase-3、bcl-2蛋白的表达变化。结果:VPA能明显抑制HeLa细胞的增殖,并呈时间和剂量依赖关系;经4mmol/L VPA处理48h后,HeLa细胞缩小变形成长梭状、胞膜皱缩、贴壁不良;VPA诱导HeLa凋亡、阻滞细胞于G2/M期,同时抑制细胞增殖;随浓度增加,VPA能明显增加caspase-3蛋白表达,并可见到蛋白裂解产物,表明VPA可以促进caspase-3活化,但下调bcl-2蛋白的表达。结论:VPA有抗宫颈癌作用,其重要作用机制之一是诱导HeLa细胞凋亡、直接抑制细胞增殖,有望成为新的抗宫颈癌药物。

Objective：To investigate the mechanisms of histone deaeetylase inhibitor sodium valproate on cell proliferation in cervical cancer cell line HeLa. Methods：Effect of VPA in various concentrations on proliferation of HeLa cells was detected by MTT;morphologic changes of HeLa cells were observed by inverted phase contrast microscope;flow cytometry was used to determine the effects of VPA on apoptosis and cell cycle distribution. The level of caspase-3 and bcl-2 protein expression was assayed by western blot. Results：The changes of the growth curve showed VPA inhibited the proliferation of HeLa cells significantly in time and dose dependent manner,after a 48 hours culture with 4mmol/L VPA,the cells exhibited deflate ,the cell membrane shrinkage and bad adherence. VPA not only induced apoptosis and caused cell cycle arrest at G2/M phase,but also inhibited the proliferation of HeLa cells. The expression of caspase-3 protein increased after treatment with VPA at a dose-dependent manner, whereas bcl-2 was down regulated. Western blot also showed cleaved caspase-3 ,which represents the activation of caspase-3. Conclusion：VPA can inhibit cervical cancer in vitro through inducing apoptosis and inhibiting cell proliferation directly. The results of this study suggest that histone deacetylase inhibitors axe hopeful to become new drugs to treat cervical cancer.