微小RNA let-7a对基底细胞样乳腺癌细胞增殖、迁移和侵袭的影响  

Effect of microRNA let-7a on proliferation,migration and invasion of basal-like breast cancer cells

作　　者：罗飞[1] 李晓宇[2] 田富国[1] 贾红燕[3] Luo Fei;Li Xiaoyu;Tian Fuguo;Jia Hongyan(Department of Breast Surgery,Affiliated Cancer Hospital of Shanxi Medical University,Taiyuan 030013,China;Department of Molecular Biology,Affiliated Cancer Hospital of Shanxi Medical University,Taiyuan 030013,China;Department of General Surgery,the First Hospital of Shanxi Medical University,Taiyuan 030001,China)

机构地区：[1]山西医科大学附属肿瘤医院乳腺外科,太原030013 [2]山西医科大学附属肿瘤医院分子生物室,太原030013 [3]山西医科大学第一医院普外科,太原030001

出　　处：《中华实验外科杂志》2020年第2期245-247,共3页Chinese Journal of Experimental Surgery

基　　金：山西省自然科学基金(201901D111396);山西省卫生厅科技课题(201201004)。

摘　　要：目的检测微小RNA(miRNA,miR)let-7a在基底细胞样乳腺癌(BLBC)细胞株中的表达,探讨miR let-7a在BLBC细胞增殖、迁移及侵袭中的作用及其机制。方法BLBC细胞株MDA-MB-468、MDA-MB-231及非BLBC细胞株MCF-7购自中国科学院上海细胞生物学研究所,实时定量聚合酶链反应(Real-time PCR)检测miR let-7a在以上细胞中的表达;使用Lipofectamin™2000脂质体转染miR let-7a至BLBC,Real-time PCR证实转染成功后,通过细胞计数试剂盒(CCK-8)法检测对细胞生存率的影响,通过划痕实验及Transwell实验检测对细胞迁移和侵袭能力的影响;通过蛋白质印迹法(Western blot)检测STAT3蛋白的表达。应用SPSS 16.0统计软件分析,数据以均值±标准差(Mean±SD)表示。两组比较采用t检验,多组比较采用ANOVA。结果miR let-7a在BLBC细胞株MDA-MB-468、MDA-MB-231中的表达明显低于非BLBC细胞MCF-7(0.13±0.02比1.01±0.23,t=9.690,P<0.01;0.31±0.08比1.01±0.23,t=7.270,P<0.01),差异有统计学意义;与对照组比较,过表达miR let-7a后,MDA-MB-468和MDA-MB-231细胞生存率较前下降(80.80±5.60比96.80±3.54,t=4.200,P<0.01和76.42±5.62比96.00±2.83,t=5.760,P<0.01),差异有统计学意义,过表达miR let-7a后,与对照组相比,MDA-MB-468和MDA-MB-231细胞的迁移(24.17±2.93比41.33±2.80,t=10.110,P<0.01和18.50±3.27比34.17±3.19,t=6.770,P<0.01)与侵袭能力(55.17±11.64比78.50±5.91,t=3.460,P<0.01和48.33±6.10比68.50±3.09,t=3.440,P<0.01)下降,差异均有统计学意义;过表达miR let-7a后,MDA-MB-468与MDA-MB-231细胞中STAT3蛋白的表达量明显降低(0.53±0.08比1.00±0.12,t=8.390,P<0.01和0.38±0.06比1.00±0.13,t=8.600,P<0.01),差异有统计学意义。结论miR let-7a在基底细胞样乳腺癌中呈低表达;上调miR let-7a的表达,可以引起基底细胞样乳腺癌的增殖和侵袭转移力下降,其机制可能是通过抑制STAT3分子相关通路实现的。Objective To investigate the effect and mechanism of microRNA(miRNA,miR)let-7a on proliferation,migration and invasion of basal-like breast cancer cells.Methods Real-time quantitative polymerase chain reaction(Real-time PCR)was used to detect the expression of miR let-7a in MDA-MB-468,MDA-MB-231 and MCF-7 cells.Then miR let-7a mimics were transfected into MDA-MB-468 and MDA-MB-231 cells to up-regulate the expression of miR let-7a;CCK-8 assay was applied to detect cell viability.Transwell assay and Wound assay were used to detect cell migration and invasion ability.The expression of signal transducer and activator of transcription-3(STAT3)was detected by Western blotting.Results The expression of miR let-7a in MDA-MB-468 and MDA-MB-231 cells was significantly lower than that in MCF-7 cells(0.13±0.02 vs.1.01±0.23,t=9.690,P<0.01;0.31±0.08 vs.1.01±0.23,t=7.270,P<0.01).The CCK-8 assay showed that proliferation rate of MDA-MB-468 and MDA-MB-231 cells decreased significantly after transfection(80.80±5.60 vs.96.80±3.54,t=4.200,P<0.01 and 76.42±5.62 vs.96.00±2.83,t=5.760,P<0.01).After transfection of miR let-7a into BLBC cells,migration and invasion were decreased(24.17±2.93 vs.41.33±2.80,t=10.110,P<0.01 and 18.50±3.27 vs.34.17±3.19,t=6.770,P<0.01)and(55.17±11.64 vs.78.50±5.91,t=3.460,P<0.01 and 48.33±6.10 vs.68.50±3.09,t=3.440,P<0.01)and the expression of STAT3 was decreased(0.53±0.08 vs.1.00±0.12,t=8.390,P<0.01 and 0.38±0.06 vs.1.00±0.13,t=8.600,P<0.01).Conclusion The expression of miR let-7a was down-regulated in BLBC cells.Upregulation of miR let-7a could inhibit proliferation,migration and invasion of BLBC cells.

关 键 词：基底细胞样乳腺癌 微小RNA let-7a 迁移 侵袭 

分 类 号：R737[医药卫生—肿瘤]