microRNA-34a在肺癌细胞凋亡中的作用

目的 探讨microRNA-34a在肺癌细胞凋亡中的作用。 方法 将A549肺癌细胞株分为3组:microRNA-34a转染组、对照组和未转染组。分析microRNA-34a在A549肺癌细胞中的表达，microRNA-34a对A549肺癌细胞生长周期、细胞增殖、细胞凋亡的影响，microRNA-34a对A549肺癌细胞Bcl-2、P53和C-MYC蛋白以及mRNA表达的影响。 结果 miRNA-34a转染组microRNA-34a的表达明显高于对照组(P<0.05)。miRNA-34a转染组G₀/G₁细胞明显高于对照组和未转染组(P<0.05)。miRNA-34a转染组48 h和96 h的增殖率明显低于对照组和未转染组(P<0.05)。miRNA-34a转染组的细胞凋亡明显高于对照组和未转染组(P<0.05)。miRNA-34a转染组的Bcl-2蛋白和C-MYC蛋白表达水平明显低于对照组(P<0.05)；miRNA-34a转染组的P53蛋白表达水平明显高于对照组(P<0.05)。miRNA-34a转染组的Bcl-2 mRNA和C-MYC mRNA表达水平明显低于对照组Bcl-2 mRNA和C-MYC mRNA表达水平(P<0.05)；miRNA-34a转染组的P53 mRNA表达水平明显高于对照组P53 mRNA表达水平(P<0.05)。 结论 microRNA-34a抑制A549肺癌细胞增殖，促进A549肺癌细胞的凋亡，机制可能为下调Bcl-2和C-MYC基因，上调P53基因。 

Role of microRNA-34a in lung cancer cell apoptosis

Objective To study the role of microRNA-34a in lung cancer cell apoptosis. Methods The A549 lung cancer cell lines were divided into three groups:microRNA-34a transfection group,control group and untransfected group.The expression of microRNA-34a in A549 lung cancer cells,the effect of microRNA-34a on A549 lung cancer cell growth cycle,cell proliferation and apoptosis,and the effect of microRNA-34a on A549 cells Bcl-2,P53 and C-MYC protein expression and mRNA expression were analyzed. Results The expression of miRNA-34a in microRNA-34a transfection group was significantly higher than that of control group(P<0.05).G₀/G₁ cells in miRNA-34a transfection group was significantly higher than that of control group and untransfected group(P<0.05).Forty-eight hours and 96 hours cells proliferation rate in miRNA-34a transfection group was significantly lower than that of control group and untransfected group(P<0.05).Apoptosis in miRNA-34a transfection group was significantly higher than that of control group and untransfected group(P<0.05).Bcl-2 protein and C-MYC protein expression levels in miRNA-34a transfection group were significantly lower than that of control group(P<0.05);P53 protein expression levels in miRNA-34a transfection group was significantly higher than that of control group(P<0.05).Bcl-2 mRNA and C-MYC mRNA expression levels of miRNA-34a transfection group was significantly lower than that of control group(P<0.05);P53 mRNA expression levels of miRNA-34a transfection group was significantly higher than that of control group(P<0.05). Conclusion MicroRNA-34a can inhibit A549 lung cancer cell proliferation and induce A549 lung cancer cells apoptosis.The mechanism may be reducing Bcl-2 and C-MYC gene and increasing P53 gene.