小分子干扰RNA沉默肝癌细胞CDK2基因对RB、CyclinE、E2F1基因表达的影响

Effect of siRNA-induced CDK2 Expression Suppression on Expression of RB, CyclinE and E2F1 in Hepatic Carcinoma Cells

【目的】观察小分子干扰RNA(siRNA)沉默细胞周期素依赖性蛋白激酶(CDK2)基因后,细胞周期相关基因RB、CyclinE、E2F1在肝癌细胞SMMC7721中mRNA的表达。【方法】将前期研究中已构建成功并筛选出的最有效干扰抑制CDK2基因的siRNA序列片段,采用Lipofectamine TM2000脂质体转染法转染肝癌细胞株SMMC7721后分6组:重组质粒组190、重组质粒组191、SMMC7721肝癌组、转染试剂组、阴性对照组、空质粒组。采用实时荧光定量PCR法检测RB、CyclinE、E2F1 mRNA水平。【结果】CDK2的siRNA转染SMMC7721细胞后,RB基因mRNA表达上调,CyclinE、E2F1基因mRNA表达下调。【结论】抑制CDK2基因的表达能使肝癌细胞SMMC7721中RB基因mRNA表达上调,CyclinE、E2F1基因mRNA表达下调,提示肝癌细胞中RB、CyclinE、E2F1基因的表达与CDK2基因的表达具有明显的相关性。

Objective To investigate the effects of cyclin-dependent kinase 2 （CDK2） expression suppression induced by small interfering RNAs （siRNAs） on mRNA expression of cell cycle related genes RB, CyclinE and E2FI in hepatic carcinoma cells SMMC7721. Methods The siRNA eukaryotic expression plasmids of CDK2 gene were constructed firstly and then were transfected into SMMC7721 cells with the Lipofeetmine TM 2000 liposome. The transfected cells were divided into six groups： recombinant plasmid 190 group, recombinant plasmid 191 group, SMMC7721 group, CDK2-siRNA transfection group, negative control group, and blank vector group. The expression of CDK2 gene was detected with Western blot method. Real-time fluorescent quantitation polymerase chain reaction （PCR） method was utilized to detect the mRNA expression of RB, Cyelin E and E2F1 which were related to CDK2 gene, and then the effective siRNA sequence of CDK2 gene was screened. Results After the siRNA eukaryotic expression plasmids of CDK2 gene was transfeeted into SMMC7721 cells, mRNA expression of RB was up-regulated and the mRNA expression of CyclinE and E2F1 was down-regulated. Conclusion CDK2 gene expression suppression can up-regulate the mRNA expression of RB in SMMC7721, and down-regulate the mRNA expression of CyelinE and E2F1, indicating that the mRNA expression of RB, Cyelin E and E2F1 genes is correlated with CDK2 gene expression.