Inhibitory effects of chemically synthetic siRNA on the expression of E6 gene in the cervical cancer cell line SiHa / 中国癌症杂志

ABSTRACT

Background and purpose:The genesis and progression of cervical cancer are closly related to E6 and E7 oncogenes of HPV.Special ribozyme and antisense oligonucleotide could inhibit the expression of E6 or E7.but both of them were not the best methods.The aim of this study was to investigate the inhibitive effect of chemically synthetic siRNA on E6 gene in the cervical cancer cell line SiHa and the following biological changes of SiHa cells.Methods:Three specific siRNAs targeting to HPV16 E6 were synthesized and transfected into SiHa cells by lipofectamine.The level of E6 mRNA was tested by RT-PCR,proliferation activities,the cell cycle distribution,expression of p53 protein and the ultramicrostructure changes of SiHa cells were detected by MTT,FCM,immunochemistry and TEM respectively.Results:All the 3 siRNAs could inhibit the level of E6 mRNA singificantly,among which siRNA1 was most effective.Decreased cellular proliferation activity was observed by MTT,especially when the cells were transfected with siRNA1 at 50 nmol/L concentration.Flow cytometry revealed obvious G1 arrest in cell cycle.The expression of p53 protein in transfected cells(0.75?0.06)was increased compared to the control group(0.43?0.03),the difference was singificant.Cell-substance concentration and vacuolus were found in endochylema by TEM.Conclusions:Chemically synthetic siRNA can interfere in the expression of E6 mRNA in SiHa cells specifically and induce the biological changes of the target cells.