摘要Objective:Recent reports suggest that Cepharanthine(CEP),a natural alkaloid extracted from the roots of Stephania Cepharanthine Hayata,can inhibit the proliferation of various cancer cells,but few studies focus on its radiosensitization in nasopharyngeal carcinoma(NPC) cells.The aim of this study was to explore the radiosensitization effect and the potential mechanisms of CEP on nasopharyngeal carcinoma cell lines CNE-1 and CNE-2.Methods:The NPC cell lines CNE-1 and CNE-2 were treated with CEP (IC50) for 48 h before irration (IR);clonogenic survival was then assessed.The apoptosis and cell cycle progression were using flow cytometry.The DNA damage repair and cycle-regulating proteins were evaluated by Western blot analysis.Results:CEP could inhibit cell growth in both cell lines.The combination of CEP and radiation promote cell cycle G2/M phase arrest and apoptosis in CNE-1 and CNE-2 cells.DNA damage repair analysis showed that CEP has an inhibitory effect on DNA repair of CNE-1 and CNE-2 cells after radiation.Conclusion:CEP enhances tumor radioresponse through multiple mechanisms that may involve the halted cell cycle progression at G2/M phase and the inhibition of DNA repair after exposure to radiation.