K-ras反义核酸抑制肺腺癌细胞A549的生长

Antisense nucleic acid of K-ras inhibits growth of lung adenocarcinoma cancer cell A549

目的:探讨K-ras反义核酸抑制肺癌生长的机制。方法:应用Western blotting检测K-ras基因在6例肺腺癌标本和A549细胞中的表达;构建K-ras基因的反义表达载体(命名为antisense-K-ras-pcDNA3.1),转染后,MTT法测细胞的生长曲线,Annexin V检测细胞凋亡;Western blotting检测cyclin A、cyclin D1、cyclin E、CDK2、CDK4、P53、Rb和caspase-3的表达。结果:在A549细胞和6例肺腺癌标本中,A549细胞和4例标本中K-ras基因高表达;MTT结果显示从第4 d开始,转染K-ras反义核酸的细胞生长明显受到抑制,而且细胞凋亡现象较明显;Western blotting显示转染反义K-ras基因的细胞中cyclin A、cyclin D1、cyclin E、CDK2和CDK4的表达降低,而caspase-3、P53和Rb的表达升高。结论:K-ras基因反义核酸能够抑制细胞生长,可能与cyclin A、cyclinD1、cyclin E、CDK2和CDK4的表达降低和caspase-3、P53、Rb的表达升高有关。

AIM： To explore the mechanism of inhibiting lung adenocarcinoma cancer mediated by antisense nucleic acid of K-ras.METHODS： The expression of K-ras was detected in A549 cells and 6 lung adenocarinoma samples.The antisense expression vector of K-ras was successfully constucted（named antisense-K-ras-pcDNA3.1）.After transfection,the growth curve and Apoptosis were determined by MTT assay and Annexin V staining,respectively.Cyclin A,cyclin D1,cyclin E,CDK2,CDK4,P53,Rb and caspase-3 were detected by Western blotting.RESULTS： K-ras was highly expressed in 4 samples of lung adenocarcinoma and A549 cells.In A549 cells transfected with antisense nucleic acid of K-ras,the cell growth was significantly inhibited and the apoptosis was visible.The expression levels of cyclin A,cyclin D1,cyclin E,CDK2 and CDK4 were significantly decreased,and the expression levels of P53,Rb and caspase-3 were significantly increased.CONCLUSION： The growth inhibition in A549 cells mediated by antisense nucleic acid of K-ras is related to the decreases in the expression of cyclin A,cyclin D1,cyclin E,CDK2 and CKD4,and the increases in the expression of P53,Rb and caspase-3.