NF-κB p65 siRNA Mediated Cell Apoptosis of Tongue Squamous Cell Carcinoma Tca8113 Cells and its Related Molecular Mechanism

Objective: To investigate effect of downregulation of p65 gene on cell apoptosis and explore the possible molecular mechanism of cell apoptosis in tongue squamous cell carcinoma cell line Tca8113 cells.Methods: Tca8113 cells were transfected with 100 nM p65 siRNA.The expression level of p65 mRNA was measured using RT-PCR at 0h,24h,48h and 72h.Meanwhile,cell apoptosis was detected using flow cytometry.Activities of caspase-3/9 was detected by Caspase-Glo○R-3/7,-8 and-9 kit,and expressions of p65,bcl-2 and bax proteins were determined using Western blotting.Results: The relative expression level of p65 mRNA in Tca8113 cells reached the lowest 48 h after transfected with p65 siRNA,and the relative expression level(0.181±0.028) in p65 siRNA group was significantly lower than that in untreated group(0.595±0.038) or control siRNA group(0.613±0.067)(P0.05).The results of flow cytometry demonstrated that p65 siRNA could induce Tca8113 cells apoptosis,and early cell apoptosis ratio(23.16±1.72%) in p65 siRNA group was significantly higher than that in untreated group or control siRNA group(P0.01).The protein levels of p65 and bcl-2 obviously decreased,and the bax protein level and activities of caspase-3/9 significantly increased 48 h after transfected with p65 siRNA.Conclusion: p65 subunit in NF-κB signaling pathway play a pivotal role in cell apoptosis of tongue squamous cell carcinoma,which will provide theoretical basis for molecular target therapy of tongue squamous cell carcinoma.