Inhibitory Effects Of Chemically Synthetic SiRNA On The Expression Of E6 Gene In The Cervical Cancer Cell Line SiHa

To investigate the inhibitive effect on E6 gene in SiHa cells of cervical cancer and the following biological changes of SiHa cells by chemically synthetic siRNA.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 ultra microstructure changes of SiHa cells were detected by MTT, FCM, immunochemistry and TEM respectively.Results: HPV16 E6 mRNA expression could be inhibited by all the 3 siRNAs significantly, Among which siRNA1 was most effective. Decreased cellular proliferation activity was observed by MTT, especially when the cells were transfected with siRNA1 at 50nmol/L concentration. Flow cytometry revealed obviously G1 arrest in cell cycle,The expression of p53 protein in transfected cells(0.75±0.06) was increased comparing to the control group (0.43±0.03),The difference was singificant. Concentrated cell-substance and vacuolus were found in endochylema by TEM..Conclusions: Chemically synthetic siRNA can interfere the expression of E6 mRNA in SiHa cells specifically and induce the biological changes of the target cells. Our study indicates that RNAi to HPV16 E6 can be used as a novel therapeutic approach for cervical cancer.