TARBP2降解AKAP12转录本促进人乳腺癌细胞转移  

TARBP2 promotes human breast cancer cell metastasis by degrading AKAP12 transcript

作　　者：王继辉 曹吉烈[1] 张立军[1] 张军[1] 鹿文葆[2] WANG Jihui;CAO Jilie;ZHANG Lijun;ZHANG Jun;LU Wenbao(Department of Orthopedics,the Fifth People's Hospital of Jinan,Jinan 250000;Institute of Microcirculation,Chinese Academy of Medical Sciences&Peking Union Medical College,Beijing 100005,China)

机构地区：[1]山东省济南市第五人民医院骨科,山东济南250000 [2]中国医学科学院北京协和医学院微循环研究所,北京100005

出　　处：《基础医学与临床》2023年第8期1259-1264,共6页Basic and Clinical Medicine

基　　金：济南市卫生健康委员会科技计划项目(2018-1-21);北京协和医学院中央高校基本科研业务费专项资金资助项目(3332019012)。

摘　　要：目的研究乳腺癌细胞中反式激活反应RNA结合蛋白2(TARBP2)转录后调控转移抑制基因A激酶锚定蛋白12(AKAP12)表达的作用及机制。方法生物信息学方法分析TARBP2在乳腺癌中的表达及其与肿瘤转移间的关联和乳腺癌中TARBP2与AKAP12表达之间的关联。利用脂质体转染后药物筛选的方法在人乳腺癌细胞系MDA-MB-231中稳定过表达TARBP2。裸鼠成瘤实验检测肿瘤肺转移;RT-qPCR检测靶基因AKAP12表达及半衰期。荧光素酶报告基因实验检测调节基因3′非编码区(3′UTR)的能力。EMSA实验检测TARBP2结合3′UTR中的茎环结构。结果人乳腺癌组织中TARBP2高水平表达且与患者淋巴结转移密切相关;TARBP2显著促进MDA-MB-231细胞肺转移(P<0.05);TARBP2显著抑制AKAP12表达(P<0.01)及其mRNA半衰期(P<0.05);TARBP2显著降低含AKAP123′UTR的报告基因荧光素酶活性(P<0.05)并结合其茎环结构;人乳腺癌组织中TARBP2表达与AKAP12表达呈显著负性关联(P<0.001)。结论TARBP2抑制AKAP12表达可能是其促进乳腺癌转移的机制之一。Objective To study the role and mechanism of trans-activation response RNA-binding protein 2(TARBP2)in post-transcriptional regulation of the expression of AKAP12,a metastasis suppressor gene,in breast cancer cells.Methods The expression of TARBP2 in breast tumor tissues and potential relationship between TARBP2 expression and tumor metastasis were analyzed by bioinformatics methods.Bioinformatics methods were used to analyze the correlation between TARBP2 and AKAP12 expression in different breast cancer datasets.MDA-MB-231 cells were transfected with GFP-tagged TARBP2 plasmids by Lipofectamine 2000 and screening with G418.Lung metastasis in tumor-bearing nude mice was detected by HE staining.RT-qPCR was used to test the expression of AKAP12 and its half-life.Luciferase assay was carried out to determine whether the transcript decay was mediated through targeting the 3′UTR.EMSA assay was performed to detect the physically binding of TARBP2 with stem-loop structure of AKAP12.Results The high expression of TARBP2 in human breast tumor tissue was closely related to lymph node metastasis.TARBP2 over-expression in MDA-MB-231 cells significantly promoted tumor metastasis in vitro(P<0.05).TARBP2 inhibited the expression of AKAP12(P<0.01)and reduced its mRNA half-life(P<0.05).TARBP2 significantly suppressed luciferase activity of AKAP123′UTR reporter(P<0.05)and bound to the stem-loop structure.There was a significant negative correlation between TARBP2 and AKAP12 expression in human breast cancer samples(P<0.001).Conclusions TARBP2-mediated inhibition of AKAP12 gene expression might be one of the mechanisms of TARBP2 promoting breast cancer metastasis.

关 键 词：乳腺癌 反式激活反应RNA结合蛋白2 A激酶锚定蛋白12 肿瘤转移 

分 类 号：R737[医药卫生—肿瘤]