Activation of LncRNA TINCR by H3K27 acetylation promotes Trastuzumab resistance and epithelial-mesenchymal transition by targeting MicroRNA-125b in breast Cancer (Retracted Article)
Activation of LncRNA TINCR by H3K27 acetylation promotes Trastuzumab resistance and epithelial-mesenchymal transition by targeting MicroRNA-125b in breast Cancer (Retracted Article)
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DOI：
10.1186/s12943-018-0931-9
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发表时间：
2019-01-08
期刊：
影响因子：
37.3
通讯作者：
Han, Mingli
中科院分区：
文献类型：
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作者：
Dong, Huaying;Hu, Jianguo;Han, Mingli
背景：曲妥珠单抗耐药并发转移是改善晚期人表皮生长因子受体2阳性（HER-2+）乳腺癌患者临床预后的主要障碍。虽然长链非编码rna （lncRNAs）可以调节细胞行为，但这些rna在HER-2+乳腺癌曲妥珠单抗耐药和转移中的作用尚不清楚。在这项研究中，我们试图确定lncRNA在晚期HER-2+乳腺癌曲妥珠单抗耐药和伴随的上皮-间质转化（EMT）过程中的调节作用。方法将SKBR-3和BT474细胞移植到小鼠模型中，经曲妥珠单抗治疗，建立耐药SKBR-3- tr和BT474- tr细胞系。采用LncRNA微阵列和定量反转录PCR （qRT-PCR）验证差异表达的LncRNA。通过Western blotting、生物信息学分析、免疫荧光测定和免疫沉淀测定（ChIP和RIP）来鉴定H3K27乙酰化与末端分化诱导的非编码RNA （TINCR）或TINCR与其下游基因miR-125b、HER-2和Snail-1之间的参与和功能相互作用。此外，我们还进行了一系列体外和体内实验来评估TINCR的功能。结果在已建立的曲妥珠单抗耐药细胞系中，观察到曲妥珠单抗和EMT的IC50值均升高。与敏感细胞相比，TINCR在曲妥珠单抗耐药细胞中的表达水平显著升高。TINCR的敲低逆转了这些细胞中的曲妥珠单抗耐药性和获得性EMT。在乳腺癌细胞的细胞质中检测到TINCR，可以海绵miR-125b，从而释放HER-2，诱导曲妥珠单抗耐药。此外，我们发现Snail-1是miR-125b的靶基因，过表达Snail-1可以逆转TINCR沉默导致的迁移、侵袭和EMT的抑制。乳腺癌中TINCR的上调归因于creb结合蛋白（CBP）介导的TINCR启动子区H3K27乙酰化。临床上，TINCR高表达的HER-2+乳腺癌患者对曲妥珠单抗治疗反应较差，生存时间较短。结论tincr可促进曲妥珠单抗耐药及伴随的EMT过程。因此，TINCR可能是一个潜在的预后指标和提高曲妥珠单抗临床疗效的治疗靶点。
BackgroundTrastuzumab resistance followed by metastasis is a major obstacle for improving the clinical outcome of patients with advanced human epidermal growth factor receptor 2-positive (HER-2+) breast cancer. While long non-coding RNAs (lncRNAs) can modulate cell behavior, the contribution of these RNAs in trastuzumab resistance and metastasis of HER-2+ breast cancer is not well known. In this study, we sought to identify the regulatory role of lncRNA in trastuzumab resistance and accompanied Epithelial-mesenchymal Transition (EMT) process in advanced HER-2+ breast cancer.MethodsTrastuzumab-resistant SKBR-3-TR and BT474-TR cell lines were established by grafting SKBR-3 and BT474 cells into mouse models and subjected to trastuzumab treatment. LncRNA microarray followed by quantitative reverse transcription PCR (qRT-PCR) was carried out to verify the differentially expressed lncRNAs. Western blotting, bioinformatics analysis, immunofluorescence assay and immunoprecipitation assays (ChIP and RIP) were performed to identify the involvement and functional interactions between H3K27 acetylation and terminal differentiation-induced non-coding RNA (TINCR) or between TINCR and its downstream genes including miR-125b, HER-2 and Snail-1. In addition, a series of in vitro and in vivo assays were performed to assess the functions of TINCR.ResultsAn increase in both, IC50 value of trastuzumab and EMT was observed in the established trastuzumab-resistant cell lines. The expression level of TINCR was significantly increased in trastuzumab-resistant cells when compared with sensitive cells. Knockdown of TINCR reversed the trastuzumab resistance and the acquired EMT in these cells. TINCR was detected in the cytoplasm of breast cancer cells and could sponge miR-125b, thereby releasing HER-2 and inducing trastuzumab resistance. In addition, Snail-1 was found to be the target gene of miR-125b and overexpression of Snail-1 could reverse the suppressed migration, invasion, and EMT caused by TINCR silencing. The upregulation of TINCR in breast cancer was attributed to the CREB-binding protein (CBP)-mediated H3K27 acetylation at the promoter region of TINCR. Clinically, HER-2+ breast cancer patients with high TINCR expression levels were associated with poor response to trastuzumab therapy and shorter survival time.ConclusionTINCR could promote trastuzumab resistance and the accompanied EMT process in breast cancer. Therefore, TINCR might be a potential indicator for prognosis and a therapeutic target to enhance the clinical efficacy of trastuzumab treatment.