miRNA-125a靶向调控SMURF1对结肠癌生物学行为的影响

miRNA-125a Targets SMURF1 to Regulate Biological Behavior of Colon Cancer

目的探讨miRNA-125a通过对靶基因SMURF1的调控在结肠癌中的影响。方法 qRT-PCR检测结肠癌患者血清中miRNA-125a和SMURF1表达水平并分析其与结肠癌相关临床指标的相关性;microRNA靶基因数据库预测miRNA-125a靶基因SMURF1并使用荧光素酶报告基因法验证其结合;qRTPCR和Western blot检测miRNA-125a模拟物对SMURF1mRNA及蛋白表达的影响;HE染色检测结肠癌组织中SMURF1的表达;CCK-8法、细胞划痕实验及流式细胞法检测miRNA-125a模拟物和SMURF1对SW480细胞增殖、迁移及周期的影响;构建结肠癌肿瘤异种移植小鼠模型,采用称重及PCNA染色检测miRNA-125a模拟物对小鼠体内肿瘤生长的影响。结果结肠癌患者血清中miRNA-125a表达水平与结肠癌相关临床指标呈负相关性,SMURF1表达水平与结肠癌相关临床指标呈正相关性。结肠癌组织中miRNA-125a的表达水平显著降低,miRNA-125a模拟物可抑制SMURF1的mRNA翻译及蛋白水平。结肠癌肿瘤组织中SMURF1表达水平明显升高,miRNA-125a模拟物可以抑制SW480细胞的增殖、迁移和S期细胞周期的聚集,然而这种抑制效果会因SMURF1表达升高而减弱。miRNA-125a模拟物抑制小鼠体内结肠癌生长及SMURF1的表达。结论 miRNA-125a通过下调SMURF1的表达在结肠癌的发展过程中发挥抑制作用,具有成为结肠癌诊断及治疗靶点的潜力。

Objective To investigate the effect of miRNA-125a on biological behavior of colon cancer through regulating SMURF1.Methods The expression of miRNA-125a and SMURF1 in the serum of colon cancer patients were detected by qRT-PCR and their correlation with clinical indicators related to colon cancer was analyzed.The microRNA target gene database predicted the combination of miRNA-125a target gene and SMURF1 which was also verified by luciferase reporter gene method.qRT-PCR and Western blot were used to detect the effect of miRNA-125a mimic on the mRNA and protein expression of SMURF1.HE staining was used to detect the expression of SMURF1 in colon cancer tissues;CCK-8 method,cell scratch test and flow cytometry were used to identify the effects of SMURF1 on the proliferation,migration and cycle of SW480 cells.The mouse model of colon cancer xenografts was constructed and the effect of miRNA-125a mimics on tumor growth in mice was detected by weighing and PCNA staining.Results The expression of miRNA-125a in the serum of patients with colon cancer was negatively correlated with the clinical indicators of colon cancer.The expression of SMURF1 was positively correlated with the clinical indicators of colon cancer.The expression level of miRNA-125a in colon cancer tissues was significantly reduced.The miRNA-125a mimic inhibited SMURF1 mRNA translation and protein levels.The expression of SMURF1 in colon cancer tissues was significantly increased.miRNA-125a mimics could inhibit the proliferation,migration and cell cycle accumulation of SW480 cells.However,this inhibitory effect could be compensated by the increased expression of SMURF1.miRNA-125a mimics inhibited the growth of colon cancer and SMURF1 expression in mice.Conclusion miRNA-125a plays an inhibitory role in the development of colon cancer by down-regulating the expression of SMURF1,and it is a potential target for the diagnosis and treatment of colon cancer.