Exploration Of INOS Inhibitor Effects To Nasopharyngeal Cancer Cell Line CNE-2

Objective:To investigate whether the selective iNOS inhibitor SMT can inhibit nasopharyngeal carcinoma cells CNE-2 proliferation,to investigate whether SMT can raise chemotherapy effect of cisplatin onCNE-2 cells and its mechanism.Methods:1 RT-PCR was used to detect the CNE-2 cell iNOS mRNA expression.2 The effects of the different treatment(SMT,CDDP,CDDP+SMT) on CNE-2 cells proliferation were analyzed by MTT assay.3 The morphology of cell apoptosis were analysed by HOECHST 33258 staining,and the cell apoptosis index(AI)were analysed by flow cytometry.4 The amount of nitric oxide was determined by The Nitrate reductase asssy.Results:1.CNE-2 cells expressed iNOS,compared with high iNOS level of lung cancer cells A549.2.SMT inhibited CNE-2 cells growth in a dose-dependent manner.3.0.5 umol/mL SMT combined with 6μg/ml cisplatin inhibited CNE-2 cells proliferation and induced CNE-2 cells apoptosis more prominently than they treated CNE-2 cells respectively,CNE-2 cell apoptosis rates were(22.26±1.37)%VS(38.8±1.25)%.4 Compared with the control group,the "SMT+cisplatin" obviously change the amount of nitric oxide.The amount of nitric oxide was (9.05±0.02)umol/l VS(14.79±0.03)umol/l.Conclusion:1.SMT inhibited CNE-2 cells growth in a dose dependent manner.2.SMT can enhance the anti-cancer effects of cisplatin,the molecular mechanism may relate to the amount of nitric oxide,and the specific mechanisms have yet to be further studied.