没食子儿茶素没食子酸酯诱导人口腔上皮癌细胞G1期阻滞

目的 探讨没食子儿茶素没食子酸酯(EGCG)对人口腔上皮癌KB细胞株增殖的影响及其分子机制.方法 采用MTT法测定EGCG对KB细胞增殖的抑制作用;应用流式细胞术分析经EGCG处理48 h后KB细胞周期改变;通过RT-PCR和免疫印迹分别检测Cyclin A、Cyclin D1和Cyclin E表达改变.结果 EGCG对KB细胞增殖具有抑制作用,EGCG(25,50,100,200,400,800μmol/L)作用KB细胞48 h后,细胞活性分别是(85.4±2.4)%、(80.4±2.8)%、(51.5±4.5)%、(30.2±1.9)%、(25.3±1.5)%和(20.0±1.1)%,与对照组(100.0±2.2)%比较具有显著性差异(P<0.05);24 hMTT结果也显示相同趋势,呈浓度依赖;EGCG(100μmol/L)处理后G1期细胞百分数为(73.5±4.4)%,与对照组(47.3±3.5)%比较具有显著性差异(P<0.05);EGCG下调Cyclin A和Cyclin E表达.结论 EGCG通过诱导G1期阻滞,抑制KB细胞增殖,其诱导细胞周期阻滞作用与下调Cycline E表达相关.

Abstract：

Objective To explore the effects of epigallocatechin-3-gallate(EGCG)on the proliferation ofhuman oral epithelial cancer eell line KB cells and the molecular mechanisms.Method KB cells were treated with various concentrations of EGCG for 24 or 48 h.MTT assay was used to test the cell viability.The changes of cell cycle in KB cells treated with EGCG for 48 h were analyzed using flow cytometry.The expressions of cyclin A,cyclin D1 and cyclin E were detected by RT-PCR and Western blotting.Reset The viability of KB cells treated with various concentrations of EGCG(25,50,100,200,400,and 800 μmol/L)for 48 h were decreased to(85.4±2.4)%,(80.4±2.8)%,(51.5±4.5)%,(30.2±1.9)%,(25.3±1.5)%,(20.0±1.1)%,respectively,showing significant difference from that of the control group(100.0±2.2)%,P<0.05).EGCG decreased the viabilities of KB cells in a dose.dependent manner. Flow cytometry demonstrated that treatment with EGCG significantly increased the cell percentage in sub-G1 phase,which was(73.5±4.4)%after a 48-h EGCG treatment,significantly different from that in the control group(47.3±3.5)%,P<0.05),EGCG-induced G1 phase arrest was correlated to the down-regulation of cyclin A and cyclin E.Conclusion EGCG inhibits the proliferation of KB cells by inducing G1 phase arrest,which involves the downregulation of cyclin E.

Epigallocatechin-3-gallate induces G1 phase cell cycle arrest in KB cells

Objective To explore the effects of epigallocatechin-3-gallate(EGCG) on the proliferation of human oral epithelial cancer cell line KB cells and the molecular mechanisms.Method KB cells were treated with various concentrations of EGCG for 24 or 48 h.MTT assay was used to test the cell viability.The changes of cell cycle in KB cells treated with EGCG for 48 h were analyzed using flow cytometry.The expressions of cyclin A,cyclin D1 and cyclin E were detected by RT-PCR and Western blotting.Result The viability...