miR-126介导的IGF2／IGF1R／IRS1信号活化促进ErbB2阳性乳腺癌细胞对Herceptin的耐受  

miR-126-mediated activation of IGF2/IGF1R/IRS1 signaling promotes the Herceptin resistance in ErbB2 positive breast cancer cells

作　　者：罗利云[1] 贾小婷[1] 郑国沛[1] 贺智敏[1] 

机构地区：[1]广州医科大学附属肿瘤医院肿瘤研究所,广州恶性肿瘤治疗转化医学重点实验室,广州510095

出　　处：《中国医师杂志》2017年第2期163-167,共5页Journal of Chinese Physician

基　　金：国家自然科学基金项目（81402196,81672616）,广州市属高校科技计划项目（1201430498）,广州市科技计划项目（2014J4100061）

摘　　要：目的探索胰岛素样生长因子也（IGF2）／胰岛素样生长因子-1受体（IGF1R）／胰岛素受体底物-1（IRSI）信号通路在ErbB2阳性乳腺癌细胞对Herceptin耐药中的作用。方法qRT-PCR和western blot技术检测各细胞中的IGF2、IGF1R和IRS1的表达及其活化情况。荧光素酶报告基因验证miR-126对IRS1的靶向调控作用。在SKBR3／pool2细胞中分别抑制IGF1R活性、干预IRSl或miR-126表达，四唑氮化合物（MTS）检测该类细胞对Herceptin的敏感性。结果相比于ErbB2阳性的亲本乳腺癌细胞SKBR3，在Herceptin耐受SKBR3／pool2中IGF2／IGF1R／IRS1信号通路活化，表现为IGF2、IGF1R和IRS1表达上调，且伴有IGF1R和IRS1活化；在SKBR3／pool2中使用IGF1R抑制剂PPP（picropodophyllin）可抑制该细胞IGF1R／IRS1信号活化，且增加该细胞对Herceptin的敏感性。用shRNA干扰IRS1可增加SKBR3／pool2细胞对Herceptin的敏感性。生物信息学预测结合报告基因实验证实miR-126可靶向调控IRS1。在SKBR3／pool2细胞中过表达miR-126可明显增加该细胞对Herceptin的敏感性。结论IGF2／IGF1R／IRS1信号通路参与介导ErbB2阳性乳腺癌细胞对ErbB2靶向药物Herceptin的耐受。Objective To explore the role of insulin-like growth factor-2/insulin-like growth factor- 1 receptor/insulin receptor substrate-1 （ IGF2/IGF1R/IRS1 ） signal pathway inducing the ehemoresistance of epidermal growth factor receptor 2 （ErbB2） positive breast cancer cells to Herceptin. Methods Quantitative real-time polymerase chain reaction （qRT-PCR） and Western blot assay were used to determine the expression levels of IGF2, IGF1 R, and IRS1. The direct targets of miR-126 were validated by dual-lucifer- ase reporter gene assay. In SKBR3/poo]2 cells, IGF1R activity was reduced by an inhibitor of IGF1 R, and IRS1 was knocked-down by shRNAs. Furthermore, 3-（4,5-dimenthyhhiazol-2-yl） -5-（ 3-carboxymethoxy- phenyl） -2-（4-sulfophenyl） -2H-tetrazolium （MTS） assay was performed to evaluate the sensitivity of these treated ceils to Herceptin. Results IGF2, IGF1R, and IRS1 were significantly higher expressed in SKBR3/pool2 cell compared to that in SKBR3 cell. Western blot assay showed that IGF2/IGF1R/IRS1 was activated in SKBR3/pooI2 cells. Bioinformatics analysis combined with luciferase activity suggested that miR-126 directly targeted IRS1. MTS results demonstrated that the chemosensitivity to Herceptin of SKBR3/ pool2 cells with inhibitor of IGF1R or shRNAs targeting IRS1 or overexpressing miR-126 was significantly reduced. Conclusions IGF2/IGF1R/IRS1 signal pathway confers to the chemoresistance of ErbB2 positive breast cancer cells to Herceptin.

关 键 词：微RNAs 胰岛素样生长因子Ⅱ 受体 IGF1型 受体 胰岛素 乳腺肿瘤/药物疗法/代谢 药物耐受性 抗体 单克隆/治疗应用 

分 类 号：R737.9[医药卫生—肿瘤]