RNA干扰SMYD3基因表达对诱导肝癌细胞凋亡的影响  

Inhibition of SMYD3 Gene Expression by RNA Interference Induces Apoptosis in Human Hepatocellular Carcinoma Cell Line HepG2

作　　者：徐鋆耀[1] 陈立波[2] 徐鋆阳[3] 杨镇[1] 魏海燕[2] 许荣华[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院综合外科,湖北武汉430030 [2]华中科技大学同济医学院附属协和医院普外科,湖北武汉430030 [3]华中科技大学同济医学院附属协和医院神经内科,湖北武汉430030

出　　处：《癌症》2006年第5期526-532,共7页Chinese Journal of Cancer

基　　金：国家自然科学基金(No.30200273)~~

摘　　要：背景与目的:SMYD3(SETandMYNDdomain-containingprotein3)基因的表达蛋白是一种组蛋白甲基转移酶,参与肿瘤细胞增殖与凋亡的调控。本研究旨在探讨利用RNA干扰(RNAinterference,RNAi)抑制SMYD3基因表达对肝癌细胞增殖与凋亡的影响。方法:RT-PCR、免疫组织化学法分别检测SMYD3在肝癌细胞和肝癌组织中的表达。构建小发夹状RNA(smallhairpinRNA,shRNA)干扰质粒Pgenesil-1-s1、Pgenesil-1-s2及无干扰效应质粒Pgenesil-1-hk并转染入肝癌细胞HepG2,阻抑其表达SMYD3,以空质粒Pgenesil-1转染组为对照。Westernblot检测阻抑效应;MTT检测细胞增殖抑制率,流式细胞术及TUNEL检测细胞凋亡。结果:SMYD3在肝癌组织和多种肝癌细胞中表达明显增强。shRNA转染HepG2细胞后:SMYD3蛋白表达下调75%～85%;细胞增殖明显受抑制,抑制率高达60.95%～72.14%;流式细胞术结果显示Pgenesil-1-s1组HepG2细胞凋亡率(17.68±2.36)%、Pgenesil-1-s2组(19.07±1.78)%,均显著高于Pgenesil-1-hk组[(1.44±0.28)%]及Pgenesil-1组[(0.47±0.12)%](P<0.01);TUNEL检测的凋亡指数结果与流式细胞术检测结果类似。结论:SMYD3高表达于多种肝癌细胞及肝癌组织;RNAi能特异性下调SMYD3的表达,抑制肝癌细胞增殖并促进细胞凋亡,提示其可能为治疗肝癌提供新的途径。BACKGROUND ＆ OBJECTIVE： SET and MYND domaincontaining protein 3 （SMYD3） gene was found to encode a histone methyltransferase involved in the proliferation and apoptosis of cancer cells. This study was to detect the expression of SMYD3 in hepatocellular carcinoma （HCC） cell lines, and reveal its function of regulating proliferation and apoptosis of HCC cell line through gene silencing. METHODS. The expression of SMYD3 in HCC cell lines HepG2, Hep3B, SMMC7721, and normal hepatic cell line L-02 was detected by reverse transcriptionpolymerase chain reaction （RT-PCR）; its expression in 24 specimens of HCC and peri-cancer tissue was detected by immunohistochemistry. Short hairpin RNA （shRNA） plasmids Pgenesil-1-sl and Pgenesil-1-s2 （with interfering effect）, and Pgenesil-1-hk （without interfering effect） were constructed and transfected into HepG2 cells. Western blot was used to detect the expression of SMYD3 protein after transfection. Cell proliferation was analyzed by MTT assay; cell apoptosis was analyzed by flow cytometry （FCM） and TUNEL. RESULTS. SMYD3 was overexpressed in the HCC cell lines and HCC tissue. After transfection with shRNA, SMYD3 expression in HepG2 cells was down-regulated by 75%-85%, and the cell growth was inhibited by 60.95%-72.14%. The apoptosis rate of HepG2 cells was significantly higher in Pgenesil-1-sl and Pgenesil-1-s2 groups than in Pgenesil-l-hk and Pgenesil-1 groups [ （17.68 ±2.36）% and （19.07 ± 1.78）%, vs. （1.44±0.28）% and （0.47±0.12）%, P〈0.01]. CONCLUSION： SMYD3 is overexpressed in various HCC cell lines and HCC tissue; RNA interference can down-regulate SMYD3 expression, inhibit proliferation and promote apoptosis of HepG2 cells.

关 键 词：肝肿瘤 肝癌细胞系 RNA干扰 SMYD3 凋亡 

分 类 号：R735.7[医药卫生—肿瘤]