miR-7-5p在三阴性乳腺癌中的作用及其机制  

The role of miR-7-5p in triple-negative breast cancer

作　　者：李鹍鹏[1] 刘平贤[1] 杜新峰[1] 张浩[1] LI Kun-peng;LIU Ping-xian;DU Xin-feng;ZHANG Hao(Department of Mammary Gland,Nanyang Central Hospital,Nanyang 473000,Henan,China)

机构地区：[1]南阳市中心医院乳腺科,河南南阳473000

出　　处：《广东医学》2022年第12期1477-1484,共8页Guangdong Medical Journal

基　　金：河南省科技发展计划项目(202102310096)。

摘　　要：目的探讨miR-7-5p通过磷酸肌醇3激酶-蛋白激酶B-哺乳动物雷帕霉素靶蛋白(PI3K-Akt-mTOR)信号通路对三阴性乳腺癌(TNBC)细胞增殖、迁移及血管生成的影响。方法利用qRT-PCR检测TNBC组织、癌旁正常组织以及TNBC细胞系(MDA-MB-231、MDA-MB-453、MDA-MB-361和MDA-MB-468)和人正常乳腺上皮细胞(MCF-10A)中miR-7-5p表达水平。将MDA-MB-468细胞随机分为空白对照组、模拟物对照组、miR-7-5p模拟物组、抑制剂对照组、miR-7-5p抑制剂组、miR-7-5p模拟物+pcDNA组和miR-7-5p模拟物+pcDNA-PIK3CD组。CCK-8检测细胞活力;Transwell检测细胞迁移能力;血管拟态实验分析细胞血管生成能力;双荧光素酶实验证实miR-7-5p与PIK3CD的靶向关系;Western blot检测细胞中PIK3CD、血管内皮生长因子(VEGF)、p-PI3K、PI3K、p-Akt、Akt、p-mTOR、mTOR蛋白表达。结果miR-7-5p在TNBC组织和细胞系中下调表达(P<0.05)。上调miR-7-5p,细胞活力下降,迁移细胞数减少,血管拟态形成指数及VEGF、p-PI3K/PI3K、p-Akt/Akt、p-mTOR/mTOR下降(P<0.05);下调miR-7-5p,细胞活力明显升高,迁移细胞数增加,血管拟态形成指数及蛋白VEGF表达增加(P<0.05)。miR-7-5p直接靶向负调控PIK3CD蛋白表达。PIK3CD过表达可逆转miR-7-5p对细胞增殖、迁移、血管生成和PI3K、Akt、mTOR磷酸化水平的抑制作用。结论miR-7-5p通过靶向下调PIK3CD蛋白表达,抑制PI3K-Akt-mTOR信号通路激活,进而降低TNBC细胞增殖、迁移及血管生成能力。Objective To investigate the effects of miR-7-5p on the proliferation,migration and angiogenesis of triple-negative breast cancer(TNBC)cells through the phosphoinositide 3-kinase-protein kinase B-mammalian target of rapamycin(PI3K-Akt-mTOR)signal pathway.Methods QRT-PCR was used to detect the expression level of miR-7-5p in TNBC tissue,normal adjacent tissues,TNBC cell lines(MDA-MB-231,MDA-MB-453,MDA-MB-361 and MDA-MB-468)and human normal breast epithelial cells(MCF-10A).The MDA-MB-468 cells were randomly separated into blank control group,mimic control group,miR-7-5p mimic group,inhibitor control group,miR-7-5p inhibitor group,miR-7-5p mimic+pcDNA group,and miR-7-5p mimic+pcDNA-PIK3CD group.CCK-8 was performed to measure cell viability.Transwell was performed to measure cell migration ability.Vascular mimicry experiment was performed to analyze the angiogenesis ability of cells.Dual luciferase experiment was performed to confirm the targeting correlation between miR-7-5p and PIK3CD.Western blot was performed to measure the expression of PIK3CD,vascular endothelial growth factor(VEGF),p-PI3K,PI3K,p-Akt,Akt,p-mTOR,and mTOR proteins in the cells.Results MiR-7-5p was down-regulated in TNBC tissues and cell lines(P<0.05).After up-regulating miR-7-5p,cell viability decreased,the number of migrating cells reduced,the vascular mimicry formation index and VEGF,p-PI3K/PI3K,p-Akt/Akt,p-mTOR/mTOR decreased(P<0.05).After down-regulating miR-7-5p,cell viability significantly increased,the number of migrating cells increased,the formation index of vascular mimicry and the expression of protein VEGF increased(P<0.05).MiR-7-5p directly targeted and negatively regulated PIK3CD protein expression.PIK3CD overexpression was able to reverse the inhibitory effects of miR-7-5p on cell proliferation,migration,angiogenesis,and the phosphorylation of PI3K,Akt and mTOR.Conclusion MiR-7-5p can inhibit the activation of PI3K-Akt-mTOR signaling pathway by targeting down-regulation of PIK3CD protein expression,thereby reduces the proliferation

关 键 词：miR-7-5p 磷酸肌醇3激酶-蛋白激酶B-哺乳动物雷帕霉素靶蛋白信号通路 三阴性乳腺癌 增殖 迁移 血管生成 

分 类 号：R737.9[医药卫生—肿瘤] R73-3[医药卫生—临床医学]