沉默Smad4基因对乳腺癌MCF-7细胞增殖和凋亡的影响  

Influence of silencing Smad4 gene in proliferation and apoptosis of breast carcinoma MCF-7 cells

作　　者：刘楠楠[1] 李玉林[2] 李荣贵[2] 孙立伟[3] 刘学娟[4] 

机构地区：[1]北华大学基础医学院病理学教研室,吉林吉林132013 [2]吉林大学基础医学院病理生物学教育部重点实验室,吉林长春130021 [3]北华大学化学与生物学院生命科学研究中心,吉林吉林132013 [4]吉林大学第一医院病理科,吉林长春130021

出　　处：《吉林大学学报（医学版）》2017年第5期887-892,共6页Journal of Jilin University：Medicine Edition

基　　金：国家科技部支撑计划项目资助课题(2012BAI19B05)

摘　　要：目的:研究降低Smad4表达对乳腺癌MCF-7细胞增殖和凋亡的影响,并探讨其可能的作用机制。方法:体外培养人乳腺癌MCF-7和MDA-MB-231细胞,采用逆转录-聚合酶链反应(RT-PCR)法检测MCF-7细胞和MDA-MB-231细胞中Smad4 mRNA表达水平;Smad4-shRNA与Scramble-shRNA质粒分别稳定转染Smad4高表达MCF-7细胞,实验分为未转染MCF-7细胞组(正常对照组),采用Smad4基因沉默组和Scramble组(阴性对照组);采用CCK-8法检测各组细胞增殖能力,流式细胞术检测各组细胞凋亡率,实时荧光定量PCR(Real-time PCR)法检测增殖相关基因CDKN1A、CDK1和CDK2以及凋亡相关基因Suvivin、bcl-2、caspase 3和caspase 9mRNA表达水平。结果:各组细胞增殖能力比较差异无统计学意义(P>0.05),各组细胞CDKN1A、CDK1和CDK2mRNA表达水平比较差异无统计学意义(P>0.05);与正常对照组和阴性对照组比较,Smad4基因沉默组细胞凋亡率明显降低(P<0.01),Smad4基因沉默组细胞Suvivin和bcl-2mRNA表达水平明显升高(P<0.01),caspase 3和caspase 9mRNA表达水平明显降低(P<0.05)。结论:Smad4可以通过下调Suvivin和bcl-2的表达、上调caspase 3和caspase 9表达引起细胞凋亡。Objective：To study the effects of down-regulated Smad4 expression on the proliferation and apoptosis of breast carcinoma MCF-7cells,and to explore their mechanisms.Methods：The human breast carcinoma MCF-7 cells and MDA-MB-231 cells were cultured in vitro.RT-PCR method was used to detect the expression levels of Smad4 mRNA in MCF-7 cells and MDA-MB-231 cells.The Smad4-shRNA plasmid and Scramble-shRNA plasmid were respectively stably transfected into the MCF-7 cells with high expression of Smad4.The experiment was divided into non-transfected MCF-7 cells（normal control）group,Smad4 gene silencing group,Scramble（negative control）group.The proliferation abilities of the cells in various groups were detected by CCK-8 method.The apoptotic rates of the cells in various groups were detected by flow cytometry.Real-time PCR method was used to detect the mRNA expression levels of the proliferation-related genes CDKN1 A,CDK1 and CDK2 and the apoptosisrelated genes Suvivin,bcl-2,caspase 3 and caspase 9.Results：The proliferation abilities of cells had no statistical significance between various groups（P〈0.05）.The mRNA expression levels of CDKN1 A,CDK1 and CDK2 in the cells had no statistical significance between various groups（P〈0.05）.Compared with normal control group and negative control group,the apoptotic rate of the cells in Smad4 gene silencing group was significantly decreased（P〈0.01）,the expression levels of Suvivin and bcl-2 mRNA in Smad4 gene silencing group were significantly increased（P〈0.01）,and the mRNA expression levels of caspase 3 and caspase 9 in Smad4 gene silencing group were significantly decreased（P〈0.05）.Conclusion：Smad4 could induce the apoptosis of MCF-7 cells by downregulating the expressions of Suvivin and bcl-2 and up-regulating the expressions of caspase 3 and caspase 9.

关 键 词：SMAD4 MCF-7细胞 细胞增殖 细胞凋亡 

分 类 号：R361.3[医药卫生—病理学]