索拉非尼对肝癌细胞中PD-L1表达的影响及机制

摘要

目的 探讨索拉非尼对肝癌细胞中程序性死亡分子配体1(PD-L1)表达的影响及可能的机制.方法 分别将0、2.5、5、10 μmol /L 索拉菲尼培养液作用于肝癌细胞株HepG2,Real-time PCR和Western blotting法检测不同浓度索拉菲尼处理后HepG2细胞中PD-L1和缺氧诱导因子1α(HIF-1α)的表达水平.分别用pEGFP-N1-HIF-1α(pEGFP-N1-HIF-1α组)、shRNA-HIF-1α(shRNA-HIF-1α组)和对照质粒pEGFP-N1、shRNA-control(pEGFP-N1组、shRNA-control组)转染HepG2细胞,检测各组HIF-1α、PD-L1 mRNA及蛋白的表达.结果 索拉菲尼干预后,HepG2细胞中PD-L1和HIF-1α mRNA及蛋白的表达下调,呈浓度依赖性(P均<0.05).与pEGFP-N1组比较,pEGFP-N1-HIF-1α组PD-L1、HIF-1α mRNA及蛋白表达水平升高(P均<0.01);与shRNA-control组比较,shRNA-HIF-1α组PD-L1、HIF-1α mRNA及蛋白表达水平降低(P均<0.01).结论 索拉非尼可通过抑制HIF-1α信号通路抑制肝癌细胞中PD-L1的表达.%Objective To investigate the effect of sorafenib on the expression of programmed cell death ligand 1(PD-L1) in the hepatocellular carcinoma cells and the underlying mechanism.Methods Real-time PCR and Western blotting was applied to detect the mRNA and protein expression levels of PD-L1 and hypoxia-inducible factor-1α (HIF-1α) in HepG2 cells treated with 0, 2.5, 5, 10 μmol/L sorafenib, respectively.HepG2 cells were transfected with pEGFP-N1-HIF-1α (pEGFP-N1-HIF-1α group), shRNA-HIF-1α (shRNA-HIF-1α group) and the control plasmids including pEGFP-N1 and shRNA-control (pEGFP-N1 group, shRNA-control group), and then the mRNA and protein expression levels of HIF-1α and PD-L1 were detected.Results The mRNA and protein expression levels of PD-L1 and HIF-1α in HepG2 cells were down-regulated after sorafenib intervention in a dose-dependent manner (both P<0.05).Compared with the pEGFP-N1 group, the mRNA and protein expression levels of PD-L1 and HIF-1α increased in the pEGFP-N1-HIF-1α group (both P<0.01).Meanwhile, compared with the shRNA-control group, the mRNA and protein expression levels of PD-L1 and HIF-1α significantly decreased in the shRNA-HIF-1α group (both P<0.01).Conclusions Sorafenib can inhibit the expression of PD-L1 in liver cancer cells through inhibiting HIF-1α signaling pathway.