过表达miR-125a-5p靶向STAT3抑制结肠癌体外生长和治疗移植瘤裸鼠的研究  

Study on overexpression of miR-125a-5p targeting STAT3 inhibits colon cancer growth in vitro and treats transplanted colon cancer in nude mice

作　　者：高蕾[1] 曾俊涛 周真真 阚娜 王小红 GAO Lei;ZENG Jun-Tao;ZHOU Zhen-Zhen;KAN Na;WANG Xiao-Hong(Department of Gastroenterology,Sanya Central Hospital,Hainan Third People′s Hospital,Sanya 572000,China)

机构地区：[1]三亚中心医院/海南省第三人民医院消化内科,三亚572000

出　　处：《中国免疫学杂志》2020年第22期2731-2736,共6页Chinese Journal of Immunology

基　　金：海南省卫生厅行业科研项目(16A200141、16A200142)。

摘　　要：目的:探究过表达miR-125a-5p抑制结肠癌的机制及其对移植结肠癌裸鼠的影响及机制。方法:通过基因预测软件TargetScan、miRanda和TarBase筛选出miR-125a-5p的靶基因STAT3;miR-125a-5p mimic和pcDNA-STAT3转染SW480细胞;RT-PCR检测miR-125a-5p表达,Western blot检测STAT3、Ki67、caspase-3、E-cadherin、Vimentin、N-cadherin、Bcl-2、c-Myc和cycD表达,克隆形成实验检测细胞生长,Transwell实验检测细胞侵袭,倒置显微镜观察上皮-间质细胞形态变化;裸鼠皮下注射转染miR-125a-5p mimic的结肠癌SW480细胞构建模型,30 d后检测肿瘤重量,免疫组化检测Ki67、Vimentin表达,RT-PCR检测miR-125a-5p表达,Western blot检测Bcl-2、c-Myc和cycD表达。结果:miR-125a-5p与STAT3在3′UTR区存在结合位点,荧光素酶实验证实miR-125a-5p靶向作用于STAT3,对STAT3表达起抑制作用;在体外,与Control组相比,miR-125a-5p mimic组克隆形成率显著降低,Ki67表达显著下调,caspase-3表达显著上调,侵袭细胞数显著减少,E-cadherin表达显著上调,Vimentin和N-cadherin表达显著下调,Bcl-2、c-Myc和cycD表达显著下调;在体内,与Control组相比,miR-125a-5p mimic组肿瘤重量显著减轻,miR-125a-5p、Bcl-2、c-Myc和cycD表达显著下调,Ki67和Vimentin阳性率显著减少。结论:过表达miR-125a-5p可靶向STAT3抑制结肠癌SW480细胞增殖、侵袭和上皮间质转化,诱导其凋亡,并抑制STAT3下游靶基因Bcl-2、c-Myc和cycD表达,从而抑制结肠癌。Objective:To investigate mechanism of miR-125a-5p inhibition of colon cancer and its effect and mechanism on transplanted colon cancer in nude mice.Methods:Targeting gene STAT3 of miR-125a-5p were screened by gene prediction software TargetScan,miRanda and TarBase;miR-125a-5p mimic and pcDNA-STAT3 were transfected into SW480 cells;miR-125a-5p expression was detected by RT-PCR.Expressions of STAT3,Ki67,caspase-3,E-cadherin,Vimentin,N-cadherin,Bcl-2,c-Myc and cycD were detected by Western blot.Cell growth was detected by colony formation assay,and cell invasion was detected by Transwell.Morphology of epithelial-mesenchymal cells observed by inverted microscope.Model of colon cancer cell line SW480 transfected with miR-125a-5p mimic was injected subcutaneously in nude mice.Tumor weight was measured after 30 d,Ki67 and vimentin expressions were detected by immunohistochemistry.Expression of miR-125a-5p was detected by RT-PCR,and expressions of Bcl-2,c-Myc and cycD was detected by Western blot.Results:miR-125a-5p and STAT3 have a binding site in 3′UTR region,and miR-125a-5p directly targets STAT3 by luciferase assay,which has an inhibitory effect on STAT3 expression.In vitro,compared with Control group,miR-125a-5p mimic group showed a significant decrease in colony formation rate,a significant down-regulation of Ki67 expression,a significant up-regulation of caspase-3 expression,a marked decrease in number of invasive cells,a significant up-regulation of E-cadherin expression,and a significant down-regulation of Vimentin and N-cadherin expression,Bcl-2,c-Myc and cycD expressions were significantly down-regulated.In vivo,compared with Control group,tumor weight was significantly reduced,miR-125a-5p,Bcl-2,c-Myc and cycD expressions were significant down-regulated,Ki67 and Vimentin positive ratios were significantly reduced in miR-125a-5p mimic group.Conclusion:Overexpression of miR-125a-5p targeting STAT3 inhibits proliferation,invasion and epithelial-mesenchymal transition of colon cancer cell line SW480,induces apop

关 键 词：miR-125a-5p STAT3 抑制 结肠癌细胞SW480 

分 类 号：R734.2[医药卫生—肿瘤]