miR-124在乳腺癌中的表达及其作用机制研究  

Role of miR-124 in breast cancer and its underlying mechanism

作　　者：任晖[1] 欧剑锋[1] 赵庆丽[1] 

机构地区：[1]兰州军区兰州总医院乳腺外科,兰州市730000

出　　处：《中国肿瘤临床》2015年第20期1012-1017,共6页Chinese Journal of Clinical Oncology

摘　　要：目的:探讨miR-124表达与乳腺癌发生、发展的相关性及机制。方法:运用实时定量聚合酶链反应(q RT-PCR)检测乳腺癌细胞系以及52例患者乳腺癌癌组织和对应的癌旁正常组织样本中miR-124的表达水平。在乳腺癌细胞株MDA-MB-231和T-47D中过表达miR-124后,测定细胞增殖活性以及侵袭转移能力。构建荧光素酶报告载体p MIR-特异性蛋白1(specificity protein 1,SP1)的3'UTR,利用荧光素酶活性检测鉴定miR-124的预测靶基因SP1。q RT-PCR和Western blot法分别检测SP1的m RNA和蛋白质的表达水平。结果:miR-124在乳腺癌细胞系和癌组织中表达量下调,差异具有统计学意义(P<0.01),并与肿瘤的转移、分期、分级和预后相关。在乳腺癌细胞株MDA-MB-231和T-47D中过表达miR-124后抑制乳腺癌细胞系的增殖、侵袭以及迁移(P<0.01)。转染miR-124模拟物显著抑制荧光素酶的活性(P<0.05)。转染miR-124模拟物显著下调MDA-MB-231和T-47D细胞中SP1的m RNA(P<0.05)和蛋白质的表达水平。结论:miR-124在乳腺癌癌组织中低表达,miR-124低表达与乳腺癌不良预后有关,且miR-124可通过调控转录因子SP1抑制乳腺癌癌细胞的增殖、侵袭和转移。miR-124表达异常减少可能是乳腺癌发生、发展的重要因素。Objective： To evaluate the role ofmiR-124 in breast cancer and its underlying mechanism. Methods： Quantitative re- verse transcription-polymerase chain reaction （qRT-PCR） was employed to quantify the expression level of miR-124 in the breast can- cer cell lines and matched tissues of 52 patients. Cell proliferation, invasion, and migration of MDA-MB-231 and T-47D were deter- mined by miR-124 overexpression in vitro. Luciferase vectors （pMIR-SP1 3＇UTR） were also constructed. The predicted target gene of miR-124 was identified via luciferase activation assay. The mRNA and protein expression of SP 1 was detected via qRT-PCR and West- ern blot, respectively. Results： MiR-124 was decreased in breast cancer tissues and cell lines. This result is correlated with metastatic capacity, TMN stages, and prognosis in breast cancer tissues. In breast cancer cell lines, ectopic overexpression of miR-124 inhibited cell proliferation, invasion, and migration in vitro. MiR-124 mimics significantly inhibited luciferase activation （P〈0.05） in HEK293 cells and could significantly decrease the mRNA （P〈0.05） and protein expression levels of SP 1 in MDA-MB-231 and T-47D ceils. Con- clusion： MiR-124 could be inhibited in breast cancer. The low miR-124 expression is associated with poor prognosis. In addition, miR- 124 could inhibit cell proliferation, invasion, and migration by targeting SP 1. These findings confirm that miR-124 dowrtregulation may be a key mechanism for breast cancer carcinogenesis.

关 键 词：乳腺癌 miR-124 SP1 预后 乳腺癌细胞系 

分 类 号：R737.9[医药卫生—肿瘤]