LncRNA-ENST00000415479.1-miR-494环路促进胰腺癌的发生发展及其机制研究

Pancreatic cancer develops insidiously, progresses rapidly, causing to an extremely poor prognosis. Accumulating evidence indicates that long non-coding RNAs (lncRNAs) are implicated in a variety of cancer biogenesis, but lncRNA expression patterns and their characteristics in pancreatic cancer remain to be further systematically explored. In our previous study, we found that the expression of lncRNA ENST00000415479.1 is upregulated in pancreatic cancer tissues and can serve as an independent predictor of patients’ prognosis based on lncRNA microarray analysis and retrospective cohort validation. Downregulation of ENST00000415479.1 significantly inhibited cell proliferation, migration and invasion ability, meanwhile increased the expression of miR-494 and restrained the nuclear β-catenin protein expression. However, overexpression of miR-494 downregulated ENST00000415479.1. Therefore, we speculate that ENST00000415479.1 interacts with miR-494 and promotes pancreatic carcinogenesis through Wnt/β-catenin pathway. We will explore the mechanism of lncRNA-ENST00000415479.1-miR-494 loop in pancreatic carcinogenesis via in vitro experiments, patient samples and in vivo experiments and thus provide theoretical basis for potential diagnostic and therapeutic target.

胰腺癌起病隐匿，发展迅速，预后极差。研究表明，长链非编码RNA（lncRNA）在多种肿瘤的发生发展中发挥重要作用，但目前在胰腺癌中缺乏系统研究。我们前期通过lncRNA高通量芯片结合回顾性临床验证，发现ENST00000415479.1在胰腺癌组织中高表达，可独立预测患者预后。敲低ENST00000415479.1可抑制胰腺癌细胞增殖、迁移及侵袭，并可上调miR-494表达进而抑制其下游β-catenin核内表达，而过表达miR-494可以下调ENST00000415479.1。据此，我们推测ENST00000415479.1与miR-494相互作用，调控Wnt/β-catenin通路从而促进胰腺癌发生发展。本课题将从细胞功能、临床标本、动物实验等方面探讨lncRNA-ENST00000415479.1-miR-494环路促进胰腺癌发生发展的调控机制，为胰腺癌诊治提供新的靶点奠定理论基础。

胰腺癌是世界范围内恶性程度最高的肿瘤之一，起病隐匿，早期诊断困难，进展迅速，预后极差。对于发病机制的探索及寻找有效的治疗靶点一直是胰腺癌研究领域的热点和焦点。近年来，随着表观遗传学的研究逐渐深入，包括长链非编码RNA（Long noncoding RNA，lncRNA）等在肿瘤中的作用日益受到国内外的重视。越来越多的研究证明 lncRNA 调控了胰腺癌的发生发展，本项目对 lncRNA 的深入研究将进一步阐明胰腺癌发生发展中表观遗传学分子机制。.本课题组首先通过50对胰腺癌和癌旁组织高通量lncRNA+mRNA表达谱芯片，筛选出在胰腺癌中异常表达的lncRNAs。在此背景下，我们首次发现了lncRNA-ENST00000415479.1在胰腺癌组织中高表达，是胰腺癌患者的独立预后因素。进一步生物学功能实验发现ENST00000415479.1可促进胰腺癌细胞的增殖、迁移和侵袭等。对 ENST00000415479.1进行 基因集富集分析（GSEA）发现，Wnt信号通路相关基因受到明显调控。进一步western blot验证，干扰ENST00000415479.1表达可影响Wnt/β-catenin信号通路相关蛋白表达。结合生物信息学分析寻找到下游miR-494，通过分子生物学等实验验证了ENST00000415479.1可与抑癌基因miR-494竞争结合，进而通过Wnt/β-catenin信号通路而促进胰腺癌发生发展。本课题的实施将有助于加深理解胰腺癌发生发展过程中表观遗传学机制及信号通路的认识，为胰腺癌的诊断治疗提供有效的预后指标、新的潜在靶点和理论依据。