HBx上调TGF-β/TβR-Ⅱ通路对肝细胞癌索拉菲尼耐药的影响

Effect of activation of TGF-β/TβR-Ⅱ pathway by HBx on sorafenib resistance in hepatocellular carcinoma

目的探讨HBx上调TGF-β/TβR-Ⅱ通路对肝细胞癌索拉菲尼耐药的影响。方法选择稳定转染HBX蛋白的HepG2-HBx细胞与转染pcDNA3.1质粒的HepG2-3.1细胞,采用索拉菲尼进行药物处理,运用MTT法来检测索拉菲尼对细胞生长的抑制率,接着流式实验对细胞凋亡率加以检测。采用免疫印迹方法检测TGF-β/TβR-Ⅱ通路中TβR-Ⅱ的蛋白水平。结果 HepG2-HBx细胞的HBX蛋白表达明显高于普通的HepG2-3.1细胞(P<0.05)。MTT检测结果显示索拉菲尼对HepG2-HBx细胞的IC_(50)值为HepG2-3.1细胞的4.65倍。流式检测结果显示索拉菲尼作用24 h后,HepG2-HBx细胞的凋亡率要明显低于HepG2-3.1细胞的凋亡率(P<0.05)。免疫印迹检测显示HepG2-HBx细胞较HepG2-3.1细胞的多药耐药蛋白TGF-β表达量明显增高(P<0.05)。结论 HBx可通过上调TGF-β/TβR-Ⅱ通路的表达,从而提高索拉菲尼对肝癌细胞的耐药性,降低细胞凋亡率,HBx是引起肝癌细胞耐药的重要因素之一。

Objective To investigate the effect of activation of TGF-β/TβR-Ⅱ pathway by HBx onsorafenib resistance in hepatocellular carcinoma. Methods HBX protein was stably transfected into HepG2-HBxcells and pcDNA3.1 plasmid was transfected into HepG2-3.1 cells,followed with the sorafenib drug treatment. Cellgrowth inhibition rate and apoptosis were detected by MTT assay and the flow cytometry,respectively. Western blotwas used to detect the protein expression of TβR-Ⅱ. Results HBX protein expression in HepG2-HBx cells wassignificantly higher than that in the normal HepG2-3.1 cells（P〈0.05）. The MTT test showed that the IC（50） value ofsorafenib on HepG2-HBx cells was 4.65 times than that of HepG2-3.1 cells. Flow cytometry showed that the apoptoticrate of HepG2-HBx cells was significantly lower than that of HepG2-3.1 cells after 24 h sorafenib treatment（P〈0.05）. Western blot showed that the expression of multidrug resistance protein TβR-Ⅱ in HepG2-HBx cells wassignificantly higher than that in HepG2-3.1 cells（P〈0.05）. Conclusions HBx can activate the expression ofTGF-β/TβR-Ⅱ pathway,so as to improve the drug resistance of sorafenib on hepatocellular carcinoma cells and reducethe apoptosis rate. HBx is one of the important factors leading to drug resistance of hepatocellular carcinoma cells.