沉默生存素基因增强人肝癌细胞SMMC-7721放射敏感性

Silencing survivin gene enhances radio-sensitivity of human hepatoma SMMC-7721

为探讨沉默生存素(Survivin)基因对人肝癌细胞SMMC-7721放射敏感性的影响,利用靶向Survivin基因的RNA干扰(RNA interference,RNAi)质粒pGenesil-survivin,采用阳离子脂质体介导法转染SMMC-7721细胞后48 h,分别以RT-PCR和Western blot法检测Survivin基因mRNA和蛋白表达,以四甲基偶氮唑盐(MTT)法检测细胞增殖活性,流式细胞术检测细胞周期和细胞凋亡,克隆存活实验检测细胞放射敏感性的变化。结果表明,转染质粒pGenesil-survivin后48 h,SMMC-7721细胞Survivin基因mRNA和蛋白表达水平与对照和阴性干扰组相比明显降低(p<0.05);转染后第1—4 d,细胞增殖活性与对照组相比明显降低(p<0.05或p<0.01);转染后48 h,细胞阻滞于G2/M期(p<0.001),凋亡百分率明显高于对照组(p<0.001);转染后SMMC-7721细胞D0值减小,放射敏感性增强,增敏比为1.24。结果提示,沉默生存素基因可增强人肝癌细胞SMMC-7721放射敏感性。

In order to investigate the effect of RNA interference silencing survivin gene on radio-sensitivity of human hepatoma SMMC-7721 cells,mRNA and protein expression of survivin gene in SMMC-7721 cells after transfection with pGenesil-survivin-HIF mediated by liposome were detected by RT-PCR and western blot respectively.Cell viability was detected by MTT assay.Cell cycle distribution and apoptosis of SMMC-7721 cells were detected by FCM assay.Radio-sensitivity of SMMC-7721 cells was determined by clonogenic assay.The results showed that mRNA and protein expression of survivin gene in SMMC-7721 cells was significantly lower than that of control and negative interference group 48 h after transfection with pGenesil-survivin（p0.05）.Cell viability of pGenesil-survivin group was significantly lower than that of control group（p0.05 or P0.01）.Cells arrested in the G2/M phase of cell cycle（p0.001） and percentage of apoptosis was significantly higher than that of control group 48 h after transfection with pGenesil-survivin（p0.001）.D0 of SMMC-7721 cells after transfection with pGene-sil-survivin decreased and its radio-sensitivity increased.The radio-sensitization ratio was determined to be 1.24.These results can be suggested that silencing survivin gene enhances radio-sensitivity of human hepatoma SMMC-7721 cells.