二甲双胍联合索拉菲尼对肝癌HepG2细胞的协同抗肿瘤作用

Synergistic anti-tumor effect of metformin combined with sorafenib on hepatocellular carcinoma HepG2 cells

目的研究二甲双胍(Met)与索拉菲尼(Sor)联合对肝癌HepG2细胞的生长抑制与凋亡的影响,探讨其潜在的机制。方法MTT法检测Met、Sor及两者联合对肝癌HepG2细胞的增殖抑制作用,计算单药的半数抑制浓度(IC50)及联用时的联合指数(CI);荧光染色法观察细胞凋亡的形态学改变;流式细胞术(FCM)分析细胞凋亡率; Western blot法检测p-Erk、p-Akt及凋亡相关蛋白Bcl-2、Bax等蛋白表达水平。结果 Met与Sor联合对HepG2细胞的增殖抑制作用和凋亡诱导作用明显强于各单药组,且呈剂量依赖效应,表现出明显的协同效应(CI值<1)。Western blot结果表明,与对照组和单药组比较,Met联合Sor可明显下调HepG2细胞中磷酸化Erk蛋白、磷酸化Akt蛋白及抗凋亡蛋白Bcl-2的表达水平,上调促凋亡蛋白Bax的表达水平。结论 Met联合Sor对肝癌HepG2细胞具有协同抗肿瘤作用,机制可能与诱导细胞凋亡和下调磷酸化Erk蛋白、磷酸化Akt蛋白有关。

Objective To investigate the effects of metformin(Met)and sorafenib(Sor)on the growth inhibition and apoptosis of hepatocellular carcinoma HepG2 cells,and its potential mechanism.Methods The anti-proliferation effects of either metformin or sorafenib alone or their combination on HepG2 cells were assessed by MTT.The IC 50 values of two single drug and the CI values were calculated.The morphological changes were observed byfluorescent microscope.The apoptosis ratios were analyzed by FCM.The expression of phospho-Erk(p-Erk),phospho-Akt(p-Akt)proteins and apoptosis-related proteins Bcl-2 and Bax were detected by Western blot.Results The anti-proliferation and apoptosis induction effects were more remarkably than the two single drugs when combination with metformin and sorafenib.It appeared in a dose-dependent manner.The CI values of metformin combinated with sorafenib were all less than alone,which had a synergistic effect.Western blot indicated that metformin combinated with sorafenib could significantly decrease the expression levels of p-Erk,p-Akt,Bcl-2 and increase the expression level of Bax of HepG2 cells,as compared with the control and the single drugs.Conclusion The combination of metformin and sorafenib performs a synergistic anti-tumor effect on HepG2 cells,and its mechanism underlying may be related to apoptosis and down-regulation the expression of p-Erk and p-Akt.