siRNA沉默Livin基因表达在抑制裸鼠肝癌生长中的作用研究

Effects of siRNA silencing Livin gene expression on the suppression of hepatocellular carcinoma growth in nude mice

目的目的应用RNA干扰技术抑制人肝癌细胞株MHCC97H中凋亡抑制因子Livin的表达,研究Livin基因在抑制裸鼠肝癌细胞移植瘤生长中的作用。方法设计针对Livin基因目标序列的siRNA,将其经脂质体Lipofectamine^(TM)2000转染至肝癌细胞株MHCC97H细胞,采用RT-PCR、Westernblot方法检测转染后的MHCC97H细胞中Livin基因的mRNA和蛋白质表达。通过建立裸鼠的荧光素酶(Luciferase)标记的MHCC97H肝癌细胞移植瘤模型,监测肿瘤体积、重量,通过活体成像技术观察siRNA注射治疗移植瘤的效果。结果在Livin-siRNA转染后的MHCC97H细胞中,Livin基因的mRNA和蛋白质表达显著下降(P<0.05),siRNA注射治疗移植瘤后,肿瘤重量、体积及荧光素酶信号均显著性下降(P<0.05)。结论通过RNA干扰技术阻断MHCC97H细胞中Livin的表达,可抑制裸鼠肝癌移植瘤的生长,提示Livin基因在肝癌的发生、发展过程中起重要作用。

Objective To study the effect of inhibitor of apoptosis Livin down-regulation by small interfer- ing RNA-mediated RNA interference （RNAi） in a xenograft model of hepatocellular carcinoma cell line MH- CC97H. Methods MHCC97H cells were transfected with synthetic small interfering RNA （siRNA） targeting Livin by lipidosome LipofectamineTM2000. Expression of Livin mRNA and protein were respectively measured by reverse transcription polymerase chain reaction （RT-PCR） and Western blot. Different doses of Livin-siRNA were injected into xenografted tumors in BALB/c nude mice model in order to confirm the in vivo effect of Livin- siRNA. Results Both Livin mRNA and protein expression were significantly decreased in the experimental group compared with controls （P 〈 0.05）. In vivo, the tumor size and the signal intensity of luciferase in tumor significantly decreased after Livin-siRNA injection at 50 μmol/L concentration （ P 〈 0. 05 ）. There were no sig- nificant body weight changes of mice after siRNA injection. Conclusions SiRNA-mediated down-regulation of Livin expression can induce apoptosis in hepatocellular carcinoma in vitro and in vivo, which suggests the im- portant role of Livin gene in hepatocellular carcinoma.