Effect of EGCG on Proliferation，Apoptosis and E2F-1 Expression of Nasopharyngeal Carcinoma Cell

Objective To study the effects of epigallocatechin-3-gallate(EGCG)on proliferation and apoptosis of nasopharyngeal carcinoma cell and its mechanism. Methods The growth and proliferation of CNE-2Z cell was detected by CCK-8 assay,and apoptosis was assessed by AnnexinV/PI flow cytometry.The expressions of nuclear transcription factor E2F-1 and its regulatory protein CyclinD1 and p21 were detected by real-time quantitative PCR and Western blot. Results The proliferation of CNE-2Z cell was inhibited in a dose-dependent manner after treatment with EGCG,the apoptosis was induced as well.The expression of E2F-1 mRNA and protein in CNE-2Z cell were markedly suppressed by EGCG,and the level of its regulatory protein CyclinD1 also decreased while p21 was increased significantly. Conclusion EGCG suppressed the proliferation and induced apoptosis in CNE-2Z cell by directly or indirectly down-regulating E2F-1,which was regulated by CyclinD1 and p21.