下调miR-92a对非小细胞肺癌细胞增殖及血管生成因子表达的影响

目的探讨miR-92a下调对非小细胞肺癌(non-small cell lung cancer,NSCLC)细胞增殖及血管生成的影响。方法将NSCLC中A549细胞分为三组培养:A549组(未转染A549细胞)、sc-siRNA组(转染sc-siRNA的A549细胞)、miR-92a-siRNA组(转染miR-92a-siRNA的A549细胞)。分别采用RT-PCR和Western blot检测A549细胞和正常人支气管上皮(human bronchial epithelial,HBE)细胞中miR-92a相对表达量、PTEN、血管内皮生长因子(vascular endothelial growth factor,VEGF)蛋白相对表达水平。采用活细胞计数法和结晶紫染色实验检测各组A549细胞的增殖能力。结果 miR-92a在A549组细胞中的相对表达量高于HBE细胞(P <0. 05); A549组细胞中PTEN蛋白表达水平低于HBE细胞(P <0. 05),VEGF蛋白表达水平高于HBE细胞(P <0. 05); miR-92a-siRNA组细胞中miR-92a相对表达量降低(P <0. 05),PTEN蛋白表达水平升高(P <0. 05),VEGF蛋白表达水平降低(P <0. 05); miR-92a-siRNA组细胞中PI3K和Akt蛋白表达水平均下降(P <0. 05); miR-92a-siRNA组细胞数目减少,细胞增殖能力减弱。结论 NSCLC中A549细胞的miR-92a表达明显上调,miR-92a基因沉默能明显抑制细胞增殖、血管生成,PTEN和VEGF相关PI3K/Akt信号通路可能在此过程中发挥重要作用。

Effect of up-regulation of miR-92a on the proliferation and angiogenesis of non-small cell lung cancer

Purpose To investigate the effect of down-regulation of miR-92a on the proliferation and angiogenesis of non-small cell lung cancer(NSCLC).Methods Human NSCLC cell A549 was divided into three groups:A549 group(non-transfected A549 cells),sc-siRNA group(A549 cells transfected with sc-siRNA)and miR-92a-siRNA group(A549 cells trans-fected with miR-92a-siRNA).The relative expression level of miR-92a,PTEN and vascular endothelial growth factor(VEGF)in A549 cells and human bronchial epithelial(HBE)cells were detected by RT-PCR and Western blot respectively.The proliferation ability of A549 cells in each group was detected by living cell count and crystal violet staining experiment.Results The relative expression of miR-92a in A549 cells was significantly higher than that in HBE cells(P<0.05),the expression level of PTEN protein in A549 cells was significantly lower than that in HBE cells(P<0.05),and the expression level of VEGF protein was significantly higher than that in HBE cells(P<0.05).In the miR-92a-siRNA group,the relative expression of miR-92a decreased(P<0.05),the expression level of PTEN protein increased(P<0.05),and the expression level of VEGF protein decreased(P<0.05).The expression levels of PI3K and Akt in miR-92a-siRNA group decreased(P<0.05).the number of cells and cell proliferation ability in miR-92a-siRNA group reduced.Conclusion The expression of miR-92a in NSCLC A549 cells is up-regulated,miR-92a gene silencing can significantly inhibit cell proliferation and inhibit cell angiogenesis,PTEN and VEGF related PI3K/Akt signaling pathways may play an important role in this process.