人乳腺癌组织中miR-34a的表达及其在乳腺癌细胞系中的功能研究  

Analysis of miR-34a Expression and Funcition in Breast Cancer Tissues and Cells

作　　者：巩雅宁 刘为青[1] 张楠[1] 何玉琴[1] 洪敏[1] 董坚[1] 

机构地区：[1]昆明医科大学第一附属医院肿瘤内科,昆明650032

出　　处：《肿瘤防治研究》2013年第10期943-948,共6页Cancer Research on Prevention and Treatment

基　　金：云南省科技条件平台建设计划项目资助课题(2007DA006);云南省高校科技创新团队建设新项目资助课题

摘　　要：目的探讨miR-34a在人乳腺癌组织和细胞中的表达情况及对乳腺癌细胞系MDA-MB-231增殖、迁移侵袭和凋亡等生物学行为的影响,为研究乳腺癌组织中miR-34a的作用及深入了解乳腺癌发生发展的分子机制奠定理论基础。方法通过实时荧光定量PCR(qRT-PCR)法检测miR-34a在20例人乳腺癌组织和癌旁正常组织中表达量的差异并比较其在人乳腺癌细胞系MDA-MB-231、MCF-7和正常乳腺上皮细胞MCF-10A中的表达差异;体外利用脂质体转染技术,转染miR-34a的模拟物(miR-34a mimic)和标记FAM(绿色荧光)的阴性对照(negative control,miR-NC)进入MDA-MB-231细胞,研究miR-34a对细胞增殖活性、迁移和侵袭能力以及凋亡和周期分布的影响。结果 miR-34a在乳腺癌组织中的表达量较正常癌旁组织下调(P<0.01);在MDA-MB-231、MCF-7和MCF-10A中的表达呈依次增高的趋势(P<0.01);转染miR-34a mimic与转染miR-NC的MDA-MB-231相比,其增殖活力、迁移和侵袭能力均下降(P<0.01),凋亡增加(P<0.01),细胞周期被阻滞在G1/G0期(P<0.01)。结论 miR-34a在乳腺癌组织和细胞系MDA-MB-231及MCF-7中的表达较正常组织和MCF-10A中都明显下调;miR-34a能够抑制肿瘤细胞MDA-MB-231的增殖、侵袭迁移,增加细胞凋亡率,使细胞周期阻滞在G0/G1;miR-34a可能起到抑癌作用,其表达水平与乳腺癌的发生发展密切相关。Objective To investigate the expression of miRNA-34a in human breast cancer tissues and cell lines and its effects on the proliferation, invasion, metastasis, apoptosis and cell cycle of MDA-MB-231 cell line. This research provides theoretical basis for the deep understanding of the role which miR-34a plays in breast cancer occurrence and development. Methods The different expression of miR-34a in 20 cases of human breast cancer tissues and normal tissues, as well as in the breast cancer cell line MDA MB-231, MCF-7 and normal breast epithelial cell line MCF-10A were detected by real-time PCR. Applying liposome transfect technique, miR-34a mimic and negative control were transfected into MDA-MB-231 respectively, and the changes of cell proliferation, invasion, migration, apoptosis and cell cycle were analyzed. Results The expression of miRNA-34a was decreased in human breast cancer tissues（P〈0.01）, while increased in MDA-MB-231, MCF-7 and MCF-10A cell lines successively（P〈 0.01）.Compared with MDA MB-231 cell transfected with miR-NC, the ability of proliferation, invasion and migration of MDA-MB-231 cell decreased after the transfection of miR-34a mimic （P〈0.01）, the cell apoptosis increased（P〈0.01）, and cell cycle was arrested in the G1/G0 phase（P〈0.0l）. Conclusion The expression of miRNA-34a both in breast cancer tissues and cell lines are significant lower than that in normal tissues and MCF-10A. miR-34a can inhibit the proliferation, invasion and migration of MDA-MB-231, increase the rate of cell apoptosis, and arrest cell cycle in the G0/G~. miR-34a may act a tumor suppressor and its expression level is closely related to the occurrence and progression of breast cancer.

关 键 词：MIR-34A 乳腺癌 侵袭 迁移 抑癌基因 

分 类 号：R737.9[医药卫生—肿瘤]