同时沉默IGF-1R和EGFR基因对肝癌HepG2细胞株生长抑制的作用机理

Mechanisms of EGFR and IGF-1R Blockade by siRNA Therapy for Growth Control of Hepatocellular Cancer HepG2 Cells

目的:同时沉默表皮生长因子受体(EGFR)、胰岛素样生长因子-1受体(IGF-1R)基因,研究其抗瘤疗效及作用机理。方法:分别构建靶向EGFR、IGF-1R及两受体的小分子干扰RNA(siRNA-EGFR、siRNA-IGF-1R、siRNA-EGFR&IGF-1R),构建与任何基因无同源的阴性对照质粒(siRNA-HK),分别转染48 h后细胞周期及相关蛋白、细胞凋亡及相关蛋白、增殖变化分别采用流式、Western-blot和MTT检测。结果:同时沉默EGFR和IGF-1R组与对照组及单基因干扰组比显著性抑制了细胞增殖、诱导细胞凋亡,阻滞细胞周期G1/S期的进程,bcl-2和cdk2表达明显下调而P21和bax表达增加。结论:同时沉默EGFR和IGF-1R基因可更有效地干扰肝癌HepG2细胞株增殖、诱导细胞凋亡,其机理可能与bcl-2和cdk2表达下调和P21与bax表达增加有关,结合干扰多个受体分子可能是一种十分有前途的新的肝癌治疗途经。

Objective： To investigate the antineoplastic effects of inhibiting IGF-1R and EGFR and signaling in hepatocellular cancer（HCC） HepG2 cells by siRNA simultaneous blockade of both of IGF-1R and EGFR.Methods： The growth,cell cycle progression,cellular apoptosis,and the related proteins including bcl-2,cdk2,bax and P21 were analyzed by MTT,flow cytometry,and Western blot.Results： Forty-eight hours after transfection,silencing both of EGFR and IGF-1R inhibited transition of the cells from G1 to S phases,up-regulated expression of bax and P21,and down-regulated expression of bcl-2 and cdk2.Conclusion： siRNA simultaneous blockade of EGFR and IGF-1R inhibits the proliferation by inhibiting their G1/S phases transition via up-regulating bax and P21 expression and down-regulating cdk2 and bcl-2 expression,on the other hand,it induces apoptosis in Hep G2 cells.Combination of IGF-1R and EGFR inhibition may be a promising novel treatment approach in HCC.