缺氧诱导因子1-α参与结直肠癌细胞上皮间质转化及DNA同源重组修复的机制  

Mechanism of hypoxia-inducible factor 1-α to participate epithelial mesenchymal transition and DNA homologous recombination repair of colorectal cancer cells

作　　者：唐康[1] 程勇[1] 庞云[1] 伍鑫[1] 张百川[1] 王五艺 

机构地区：[1]重庆医科大学附属第一医院胃肠外科,重庆400016

出　　处：《中国肿瘤生物治疗杂志》2016年第6期766-772,共7页Chinese Journal of Cancer Biotherapy

基　　金：重庆市科委自然科学基金项目(No.cstc2012jjA10038)~~

摘　　要：目的:研究氯化钴(CoCl_2)模拟的细胞体外缺氧微环境对结直肠癌细胞株SW480及Caco-2上皮间质转化及DNA同源重组修复的影响并探究其机制。方法:应用不同浓度的氯化钴(CoCl_2)处理SW480及Caco2细胞72 h后,CCK8法检测细胞增殖能力,划痕及Transwell试验检测细胞的迁移及侵袭能力,流式细胞术(FCM)检测细胞周期及凋亡情况,RT-PCR及Western blotting实验检测细胞内相关基因mRNA及蛋白水平的变化情况。结果:CCK-8实验提示细胞在缺氧后增殖能力明显增加(P<0.05);划痕试验及Transwell侵袭实验提示细胞在缺氧条件下迁移及侵袭能力明显增强(P<0.05);流式细胞术提示细胞在缺氧后被阻滞在S期(P<0.05),凋亡率明显下降(P<0.05);RT-PCR试验表明缺氧后细胞内缺氧诱导因子1-α(hypoxia inducible factor 1 alpha,HIF-1α)及RAD51的mRNA水平上调(P<0.05);Western blotting实验表明在缺氧环境下细胞内HIF-1α表达上调(P<0.05),上皮-间质转化(epithelial-mesenchymal transition)相关蛋白:钙黏附蛋白E(E-cadherin)表达下调,波形蛋白(vimentin)及转录抑制因子(snail)表达上调(P<0.05),DNA同源重组相关蛋白BRCA1及RAD51表达上调(P<0.05),PI3K/AKT(磷脂酰肌醇-3-羟激酶)信号通路下游关键信号分子AKT1及共济失调毛细血管扩张症突变基因(ataxia-telangiectasia mutant gene)的编码产物ATM激酶磷酸化水平显著上调(P<0.05)。结论:慢性缺氧环境可促进结直肠癌细胞SW480及Caco-2的增殖、迁移和侵袭能力,抑制凋亡,其机制可能与HIF-1α/PI3K-AKT、HIF1-α/ATM信号通路介导EMT及DNA同源重组修复过程有关。Objective： To investigate effect of hypoxic microenviroment in vitro which built by cobalt chloride （CoC12 ） on epithelial mesenehymal transition and DNA homologous recombination repair of colorectal cancer SW480 and Caeo-2 line cells and to explore their mechanisms. Methods： After the SW480 and Caco-2 cells were treated with various concen- trations of CoC12 for 72 h, proliferation abilities of the cells were detected by CCK8 assay, migration and invasion abilities of the cells detected by scratch test and transwell assay, cell cycles and apoptosis status of the cells detected by flow ey- tometry （FCM） , changes of mRNA and protein levels of associated gene in the cells detected by RT-PCR and Western blotting assays. Results： CCK8 assay prompted that proliferation ability of the cells significantly increased after hypoxia （P 〈 0.05） ; scratch and transwell tests suggested that under hypoxia, migration and invasion abilities of the cells obvi- ously enhanced （ P 〈 0.05 ） ; FCM disclosed that after anoxic treatment the cells were maintained at S phage and apoptosis rates of the cells significantly decreased （P 〈 0.05） ; RT-PCR assay showed that mRNA levels of HIF-1a and RAD51 in the ceils after hypoxic treatment raised （ P 〈 0.05 ） ; Western blotting assay indicated that under hypoxie mieroenviroment in the cells expression of HIF1-a enhanced （P 〈 0.05 ） . expression of epithelial mesenchvmal transition （EMT） associat-process

关 键 词：缺氧诱导因子1-Α 结直肠癌 上皮间质转化 DNA同源重组修复 

分 类 号：R735.34[医药卫生—肿瘤]