Effect Of SNAIL On TRAIL - Induced Apoptosis Of Hepatocellular Carcinoma Cells And Its Mechanism

Objects: 1) To verify that silencing SNAIL downregulated the growth of hepatocellular carcinoma(HCC) cells. 2) To investigate the influence and the mechanism of silencing SNAIL on TRAIL- induced apoptosis in HCC cells.Methods: The most effective lentiviral vectors carrying sh RNA against SNAIL were selected and adenoviral vectors harboring TRAIL were constructed. The expression of SNAIL and TRAIL in the level of m RNA and protein was detected by quantitative PC R and western blotting, respectively. HCC cell viability and apoptosis were assessed using MTT assay and the Hoechst test. To determine how to sensitize HCC cells to TRAIL- induced apoptosis after silencing SNAIL, p53 was assessed by western blotting analysis. We also investigated the expression of Bcl- x L, c IAP2, survivin and Raf-1 protein using western blotting analysis and the apoptotic degree of Hu H-7 cells was detected using the Hoechst test following the suppression of each gene.Results: Lentivirus as vectors carrying sh RN A to transfect a variety of HCC cell lines can suppress the expression of SN AIL gene. Adenoviral vectors harboring TRAIL to transfect a variety of HCC cell lines can express TRAIL sustainably and stably. Silencing SNAIL resulted in increasing apoptosis by enhancing sensitization to TRAIL in all the HCC cells. Additionally, p53 protein was upregulated in Hu H-7 cells. Expression of Bcl- x L, c IAP2, survivin and Raf-1 was downregulated following silencing of SNAIL, while downregulation of any of the proteins contributed to enhancing TRAIL- induced apoptosis in HCC cells, with the exception of c IAP2.Conclusion: The results demonstrated that silencing SNAIL can sensitize TRAIL- induced apoptosis in HCC cells by upregulating p53 protein and by regulating related genes of the NF-κB pathway such as Bcl- x L, survivin and Raf-1.