miR-125a-5p靶向调控HER-2表达抑制乳腺癌细胞生物学活性  

miR-125a-5p targeted regulation of HER-2 expression and inhibition of biological activity of breast cancer cells

作　　者：骆梅青[1] 石洁琼[1] 徐胜源 黄玥[1,2] 伍爱华[1,3] LUO Meiqing;SHI Jieqiong;XU Shengyuan;HUANG Yue;WU Aihua(Department of Oncology, Affiliated Hospital of Guilin Medical College,Guilin 541001,China)

机构地区：[1]桂林医学院附属医院肿瘤内科,广西桂林541001 [2]桂林医学院附属医院乳腺外科,541001 [3]桂林医学院附属医院病理科,541001

出　　处：《临床肿瘤学杂志》2019年第6期500-505,共6页Chinese Clinical Oncology

摘　　要：目的 探讨miR-125a-5p对人表皮生长因子受体2(HER-2)基因的靶向调控作用以及对乳腺癌MCF-7细胞增殖、凋亡、周期的影响。方法 收集2017年10月至2018年3月在我院保存的57例乳腺癌组织及对应癌旁组织,提取总RNA,实时荧光定量PCR(QPCR)检测miR-125a-5p表达。向MCF-7细胞转染miR-125a-5p mimics(miR-125a-5p组)或空质粒(阴性对照组),同时设置空白对照组。采用MTT法和流式细胞术检测各组细胞增殖、凋亡和周期。采用双荧光素酶报告实验验证HER-2与miR-125a-5p的靶向关系。采用QPCR和Western blotting检测各组转染48h后HER-2mRNA和蛋白表达。结果 乳腺癌组织中miR-125a-5p表达量为0.58±0.12,低于对应癌旁组织的0.98±0.17,差异具有统计学意义(P<0.05)。miR-125a-5p表达与HER-2表达、肿瘤直径、TNM分期有关(P<0.05)。MCF-7细胞和MCF-10A细胞中miR-125a-5p的表达量分别为0.73±0.15和1.24±0.18,差异有统计学意义(P<0.05)。培养24、48、72、96后,miR-125a-5p组MCF-7细胞的增殖率分别为(87.65±5.79)%、(79.34±7.18)%、(70.17±6.21)%和(64.28±5.93)%,明显低于阴性对照组,差异有统计学意义(P<0.05)。miR-125a-5p组细胞G0/G1期细胞比例为(61.95±3.49)%,S期细胞比例为(22.57±2.76)%,与阴性对照组比较,差异有统计学意义(P<0.05)。miR-125a-5p组细胞凋亡率为(20.33±6.25)%,高于空白对照组和阴性对照组(P<0.05)。miR-125a-5p可抑制野生型HER-23'-UTR报告基因载体的荧光素酶活性,而对突变型HER-23'-UTR的荧光素酶活性无影响。miR-125a-5p组HER-2mRNA和蛋白表达水平分别为0.56±0.15和0.41±0.11,低于阴性对照组(P<0.05)。结论 上调miR-125a-5p可抑制HER-2的表达,从而抑制乳腺癌细胞增殖凋亡活性,其有望成为乳腺癌早期诊断和个体化治疗的潜在靶点。Objective To investigate the targeting regulation of human epidermal growth factor receptor 2 (HER-2) gene by miR-125a-5p and its effects on proliferation,apoptosis and cycle of breast cancer MCF-7 cells.Methods Total RNA was extracted from 57 breast cancer tissues and adjacent tissues preserved in our hospital from October 2017 to March 2018.The expression of miR-125a-5p was detected by real-time fluorescence quantitative PCR (QPCR).miR-125a-5p mimics (miR-125a-5p group) or blank plasmid (negative control group) were transfected into MCF-7 cells,and blank control group was set up.MTT and flow cytometry were used to detect cell proliferation,apoptosis and cycle.The targeting relationship between HER-2 and miR-125a-5p was validated by double luciferase reporter assay.QPCR and Western blotting was used to detect the expression of HER-2 in each group 48 hours after transfection.Results The expression of miR-125a-5p in breast cancer tissues was 0.58±0.12,lower than that in adjacent tissues 0.98±0.17,with statistical significance (P<0.05).The expression of miR-125a-5p was correlated with HER-2 expression,tumor diameter and TNM stage (P<0.05).The expression levels of miR-125a-5p in MCF-7 cells and MCF-10A cells were 0.73±0.15 and 1.24±0.18,respectively,with significant difference (P<0.05).After 24,48,72 and 96 hours,the proliferation rates of MCF-7 cells in the miR-125a-5p were (87.65±5.79)%,(79.34±7.18)%,(70.17±6.21)% and (64.28±5.93)%,respectively,which were significantly lower than those in the negative control group (P<0.05).The proportion of G 0/G 1 phase cells and S phase cells in the miR-125a-5p group was (61.95±3.49)% and (22.57±2.76)%.The difference was significant compared with the negative control group (P<0.05).The apoptotic rate of miR-125a-5p group was (20.33±6.25)%,higher than that of blank control group and negative control group (P<0.05).miR-125a-5p mimics significantly reduced luciferase expression in the psiCHECK2-HER-2-3'UTR-WT group,while not affecting the expression of the psiCHECK2-HER

关 键 词：乳腺癌 miR-125a-5p HER-2 增殖 

分 类 号：R737.9[医药卫生—肿瘤]