Department of Intensive Care Unit, The First Affiliated Hospital of Kunming Medical University, No.295 Xichang Road, Kunming, 650032, Yunnan, China.
Department of Intensive Care Unit, Huize People's Hospital, No.2 Ruixiang Road, Kunming, 654200, Yunnan, China.
Biochem Biophys Res Commun. 2019 Jun 18;514(1):118-126. doi: 10.1016/j.bbrc.2019.04.107. Epub 2019 Apr 23.
Long non-coding RNAs (lncRNAs) have been reported as essential regulators in human cancers, including lung adenocarcinoma (LUAD). In the present study, we found that lncRNA long intergenic non-protein coding RNA 467 (LINC00467) was expressed higher in TCGA LUAD samples and predicted poor prognosis in LUAD patients. High expression of LINC00467 was further detected in LUAD cell lines. Functionally, high expression level of LINC00467 promoted LUAD cell proliferation and migration, indicating that LINC00467 exerted oncogenic functions in LUAD progression. Considering the upregulation of LINC00467 in LUAD, we further detected the activator of LINC00467 promoter. Combining with bioinformatics analysis and mechanism experiments, we determined that LINC00467 was activated by STAT1 in LUAD. Moreover, high expression of LINC00467 was found to be associated with the activation of Wnt/β-catenin signaling pathway. Rescue assays demonstrated that dickkopf WNT signaling pathway inhibitor 1 (DKK1; an inhibitor of Wnt/β-catenin signaling pathway) and Wnt/β-catenin signaling involved in DKK1-mediated LUAD cell proliferation and migration. Furthermore, LINC00467 was located in the nucleus of LUAD cell lines and negatively regulated DKK1 in LUAD cells. Mechanistically, we determined that LINC00467 epigenetically silenced DKK1 by recruiting enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) to DKK1 promoter. Collectively, we determined that STAT1-induced upregulation of LINC00467 promoted LUAD progression by epigenetically silencing DKK1 to activate Wnt/β-catenin signaling pathway.
长链非编码 RNA(lncRNA)已被报道为人类癌症(包括肺腺癌[LUAD])的重要调控因子。在本研究中,我们发现 lncRNA 长基因间非蛋白编码 RNA 467(LINC00467)在 TCGA LUAD 样本中表达较高,并预测 LUAD 患者预后不良。在 LUAD 细胞系中进一步检测到 LINC00467 的高表达。功能上,LINC00467 的高表达水平促进了 LUAD 细胞的增殖和迁移,表明 LINC00467 在 LUAD 进展中发挥致癌作用。鉴于 LINC00467 在 LUAD 中的上调,我们进一步检测了 LINC00467 启动子的激活剂。结合生物信息学分析和机制实验,我们确定了 STAT1 在 LUAD 中激活了 LINC00467。此外,高表达的 LINC00467 与 Wnt/β-catenin 信号通路的激活有关。挽救实验表明,Dickkopf WNT 信号通路抑制剂 1(DKK1;Wnt/β-catenin 信号通路的抑制剂)和 Wnt/β-catenin 信号通路参与了 DKK1 介导的 LUAD 细胞增殖和迁移。此外,LINC00467 位于 LUAD 细胞系的细胞核中,并负调控 LUAD 细胞中的 DKK1。从机制上讲,我们确定 LINC00467 通过募集增强子结合锌指蛋白 2 多梳抑制复合物 2 亚基(EZH2)到 DKK1 启动子,表观遗传沉默 DKK1。总之,我们确定 STAT1 诱导的 LINC00467 上调通过表观遗传沉默 DKK1 激活 Wnt/β-catenin 信号通路促进 LUAD 进展。