Depressant Effects of the HPV16-E6-Targeted siRNA on the CaSki Cell of Cervical Cancer

To study the effects of the HPV16-E6-targeted siRNA on the biological behavior of cervical cancer cells by using RNA interference techniques and the HPV-encoded oncoprotein HPV16-E6 as a target.Moreover,we attempt to elucidate the clinical significance of its experiment.The expression vectors of HPV16-E6-targeted siRNA were constructed and transfected into the HPV16-E6-positive CaSki cells by in vitro transfection reagents.The expression levels of the HPV16-E6 mRNA and the mRNA encoded oncoproteins in cervical cancer CaSki cells were detected by RT-PCR and Western blotting,respectively.The expression and activities of the apoptosis-associated molecules were analyzed through cytochrome c assay in order to investigate the molecular mechanism of cell apoptosis induced by HPV16-E6-targeted siRNA.RT-PCR assay demonstrated that after the expression vectors of HPV16-E6-targeted siRNA weretransiently transfected into the HPV16-E6-positive CaSki cells,a variety of considerable changes occurred:the expression of E6 protein and mRNA in CaSki cells were down-regulated.Western blotting showed thatthe expression of anti-apoptotic protein Bcl-2 was also down-regulated;the cytochrome c liberation testdisplayed its release from mitochondria into cytoplasm,thus inducing the cell apoptosis.HPV16-E6-targeted siRNA can significantly inhibit the proliferation of transplanted tumor cells and induce cellapoptosis.It finds out a new approach for the functional study of this important oncoprotein HPV16-E andprovides new experimental evidences for the gene-targeted treatment of HPV16-E6-positive tumors,especially exploring a new gene therapy for HPV infection and cervical cancer.