siRNA抑制人胶质瘤细胞MDM2的表达及细胞增殖

siRNA Inhibits MDM2 Expression and Cell Proliferation in Glioma Cell Line

目的研究siRNA对人胶质瘤U251细胞MDM2基因表达的抑制作用及对肿瘤细胞增殖和凋亡的影响。方法体外合成2对针对MDM2基因的siRNA,经脂质体转染导入U251细胞;用半定量RT-PCR检测siRNA MDM2对MDM2基因表达的抑制作用;并用MTT法检测siRNA MDM2对细胞增殖抑制作用,流式细胞仪检测细胞凋亡。结果转染siRNA MDM2的细胞的MDM2基因表达分别下调到对照组的31.61%和40.18%;转染阴性对照质粒的MDM2基因没有明显改变。MTT结果表明转染siRNA MDM2后细胞生长受到抑制,与对照组比差异具有显著性(P<0.5);同时细胞发生凋亡和细胞周期阻滞,转染siRNA MDM2-1,2的凋亡率分别为49.9%和40.0%,转染阴性对照质粒和对照组未检测出明显的增殖抑制和凋亡改变。结论 siRNA MDM2可以有效抑制U251细胞株中MDM2的表达,并抑制细胞增殖,诱导细胞凋亡。

Objective To study the inhibitory effect s of siRNA on MDM2 expression in glioma cell line U251 and cell proliferation.Methods siRNA targeting MDM2（PGCsilencer TM-MDM2-siRNA） was const ructed and transfercted into U251 cells.Meanwhile,cont rol siRNA was transfected and the transfection agent was used as the comparison.MDM2 gene expressions were measured using RT-PCR.Cell proliferation was measured with MTT assay.Results RT-PCR result showed that MDM2 mRNA expression levels were reduced to 31.61 % and 40.18 % after being transfected with siMDM2-1 and siMDM2-2;The difference between control siRNA and liposome group was not obvious（P0.05）.The result s of MTT and flow cytometer showed that siRNA could suppress the proliferation and induce apoptosis of U251 cells.Conclusion siRNA can effectively down-regulate MDM2 expression in U251 cell line;inhibit the cell proliferation and induce apoptosis