siRNA抑制人肝癌细胞MDM2表达及细胞增殖的研究

目的探讨siRNA对人肝癌HepG2细胞MDM2基因表达的抑制作用及对增殖的影响。方法体外合成针对MDM2基因的siRNA质粒,转染HepG2细胞株;应用RT-PCR和western blot方法检测siRNA对MDM2和P53基因和蛋白表达的影响,并用MTT法检测siRNA对细胞增殖抑制作用,流式细胞仪检测细胞周期。结果和空白组比转染siMDM2-1,2的HepG2细胞的MDM2基因和蛋白表达减低,而P53基因和蛋白表达增加。阴性对照质粒组的基因表达未见明显改变。转染siRNA MDM2后细胞生长受到抑制,转染siMDM2-1,2和阴性对照质粒后的抑制率分别是46.3%、56.1%和3%。和对照组比较,转染siMDM2-1,2的hepG2细胞的细胞周期发生明显改变,而转染对照质粒的hepG细胞周期未发生明显变化。结论 siRNA MDM2可以有效抑制HepG2细胞株中MDM2的表达,促进P53的表达,同时可以使细胞周期发生变化,这可能是其抑制肿瘤细胞增殖的主要机制之一。

siRNA inhibits MDM2 expression and proliferation of hepatoma carcinoma cell

Objective Using siRNA to downregulate MDM2 expression in hepatocellular carcinoma cell line hepG2,to observe the influence of siRNA of cell proliferation and apoptosis.Methods MDM2-siRNAs against the MDM2 gene were designed and transfected into hepG2 cells respectively,MDM2 and P53 gene and protein expression was measured using RT-PCR and western blot,Cell proliferation was measured with MTT assay,the cell cycle were analysed using flow cytometer.Results MDM2 mRNA and protein expression were inhibited and P53 mRNA and protein expression were enhanced after transfecting with two siRNA MDM2 respectively.As a consequence,cell growth inhibition was observed,cell cycle change was observed after transfecting with two siRNA MDM2 too.Conclusion siRNA against MDM2 could effectively downregulate MDM2 and upregulate P53 expression in hepG2 cell line,inhibit cell proliferation and change cell cycle.