表没食子儿茶素没食子酸酯通过调控P53/miR-34a抑制鼻咽癌细胞的增殖

目的:观察表没食子儿茶素没食子酸酯(EGCG)对鼻咽癌细胞增殖的影响,并以微小RNA-34a(miR-34a)为靶点探讨其作用机制。方法:不同浓度的EGCG处理CNE-2Z细胞,CCK-8法、Ed U染色法和平板克隆形成实验检测细胞增殖能力的改变;流式细胞术检测细胞周期分布的改变;Western blot检测P53和Notch1蛋白水平的变化;real-time PCR检测miR-34a和Notch1 mRNA的表达。结果:EGCG处理后,CNE-2Z细胞的增殖受到明显抑制,克隆形成能力降低,细胞周期阻滞于G0/G1期,呈剂量依赖关系;随着EGCG浓度增高,P53和miR-34a的表达水平明显上调,而其下游Notch1 mRNA和蛋白的表达水平则明显下降。结论:EGCG可能通过调控P53/miR-34a/Notch1通路诱导细胞周期阻滞,抑制鼻咽癌细胞增殖。

Inhibitory role of epigallocatechin-3-gallate in proliferation of human nasopharyngeal carcinoma cells by targeting P53/miR-34a

AIM: To study the effect of epigallocatechin-3-gallate(EGCG) on the proliferation of human nasopharyngeal carcinoma(NPC) cells, and to explore its mechanism by targeting miR-34a.METHODS: Nasopharyngeal carcinoma CNE-2Z cells were treated with various concentrations of EGCG. The ability of cell proliferation was detected by CCK-8 assay, 5-ethynyl-2-deoxyuridine(EdU) incorporation assay and colony-forming assay. The cell cycle distributions were analyzed by flow cytometry. The protein levels of P53 and Notch1 were detected by Western blot. The expression of miR-34a and Notch1 mRNA was measured by real-time PCR.RESULTS: EGCG effectively inhibited the proliferation and colony formation of CNE-2Z cells in a dose-dependent manner, which was related to its induction of cell cycle arrest at G₀/G₁ phase. The expression of P53 and miR-34a in CNE-2Z cells was significantly increased after treated with EGCG, while the expression of Notch1 at mRNA and protein levels was markedly suppressed.CONCLUSION: EGCG induces cell cycle arrest and suppresses cell proliferation by regulating the P53/miR-34a/Notch1 pathway in NPC cells.