表没食子儿茶素没食子酸酯对常氧及低氧状态下胰腺癌细胞的作用  

Epigallocatechin-3-gallate inhibits the proliferation of human pancreatic cancer cells by down regulating matrix metalloproteinase-2 and vascular endothelial growth factor expressions under normoxia and hypoxia

作　　者：舒时珍[1] 王琪[1] 姚静静[1] 刘婷婷[1] 蒋荷[1] 王立夫[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院消化内科,上海200025

出　　处：《内科理论与实践》2012年第4期300-304,共5页Journal of Internal Medicine Concepts & Practice

基　　金：国家自然科学基金(项目编号:30971130);上海市科学技术委员会基础重点研究项目(项目编号:11JC1407601)

摘　　要：目的:探讨表没食子儿茶素没食子酸酯(EGCG)对在常氧及低氧诱导下人胰腺癌细胞株BxPC-3的增殖、凋亡的影响及其相关基因的表达。方法:采用氯化钴(CoCl2)建立低氧模型,在常氧及低氧状态下,研究不同浓度EGCG对人胰腺癌细胞株BxPC-3的作用。采用四唑氮蓝(MTT)还原法检测细胞活力;流式细胞仪检测细胞凋亡;逆转录聚合酶链反应(RT-PCR)检测细胞基质金属蛋白酶2(MMP-2)和血管内皮生长因子A(VEGF-A)mRNA水平的表达变化;蛋白质印迹法(Western-blot)检测MMP-2和VEGF-A蛋白水平的表达变化。结果:低浓度的EGCG短时间内对BxPC-3细胞的生长无显著抑制作用,但随着作用时间的延长和剂量的增加,EGCG显示了细胞生长抑制作用;流式细胞仪结果显示EGCG可诱导胰腺癌细胞凋亡,低氧状态下其抑制作用低于常氧状态。EGCG可显著抑制MMP-2和VEGF-A蛋白的表达,下调MMP-2和VEGF-A mRNA的表达。结论:EGCG无论在常氧或低氧环境下均可以显著抑制胰腺癌BxPC-3细胞的生长,促进其凋亡,低氧状态下其抑制作用低于常氧状态下,提示在临床上胰腺癌化学治疗效果差可能与其肿瘤内低氧状态有关。其可能相关机制与下调VEGF、MMP-2表达水平有关。Objective To study the effect of epigallocatechin-3-gallate （EGCG） on human pancreatic cancer cells and related genes expression under normoxia and hypoxia. Methods In vitro hypoxic model was established by COC12. Proliferation and apoptosis of pancreatic cancer cells under EGCG and normoxia or hypoxia were studied, and the expressions of related genes matrix metalloproteinase-2 （MMP-2） and vascular endothelial growth factor A （VEGF-A） were assessed by flow cytometry, RT-PCR, and Western blotting. Results EGCG significantly inhibited proliferation of pancreatic cancer cells, and induced apoptosis in a dose- and time-dependent manner under normoxia and hypoxia,and was stronger under normoxia than under hypoxia. EGCG could significantly reduce the levels of MMP-2 and VEGF protein and the expressions of MMP-2 and VEGF-A mRNA. Conclusions Under normoxia and hypoxia, EGCG inhibited proliferation of human pancreatic cancer cells and induced apoptosis by down regulating the expressions of MMP-2 and VEGF, and the effect was stronger under normoxia than under hypoxia. The poor results of EGCG in pancreatic cancer chemotherapy in clinical trial suggested that it might be related to the hypoxic microenvironment of solid tumor. The role of EGCG might be associated with inhibition of tumor angiogenesis by down-regulating the expression of MMP-2 and VEGF.

关 键 词：表没食子儿茶素没食子酸酯 胰腺癌细胞 低氧模型 基质金属蛋白酶2 血管内皮生长因子A 

分 类 号：R735.9[医药卫生—肿瘤]