Abstract:
Objective To investigate the effects of shRNA-mediated FANCD2 knock down on the chemotherapy sensitivity to CDDP of human head and neck squamous cell carcinoma (HNSCC) cells SIHN-005A and the underlying mechanisms.
Methods The human HNSCC cells SIHN-005A which FANCD2 gene was stably silenced were obtained from our previous experiments and puromycin was used as the selection agent. The silencing effect was detected by Western blot. CCK-8 assay was used to observe the inhibition ratio of cells growth. The apoptosis and morphology changes were detected and observed by fluorescent Hoechst staining. The cell cycle D1 protein (Cyclin D1), Bax, Bcl-2 and HIF-1α were detected by Western blot.
Results The FANCD2 protein expression was significantly decreased in experimental group (shRNA) and the silencing efficiency reached 60.5%. The proliferation inhibition rate was significantly higher in the experimental group (shRNA) than those in the negative control group (shRNA-C) and blank control group (Control), and it was in a concentration and time-dependent manner. IC50 of CDDP concentration of shRNA group was much lower than both shRNA-C group and Control group. The apoptosis rate was increased significantly in shRNA group. Cyclin D1, Bcl-2 and HIF-1α protein expression were significantly down-regulated in experimental group after CDDP administration, the expression of Bax protein was significantly increased in the experimental group.
Conclusion shRNA-mediated FANCD2 knock down could improve the sensitivity of HNSCC SIHN-005A cells to CDDP. The mechanism may be related to the changes in the protein expression of Bax/Bcl-2, Cyclin D1 and HIF-1α which were caused by FANCD2 knock down.