lncRNA-PATB通过调控TGF-β/SMAD3通路促进胰腺癌EMT和侵袭转移的研究

The invasion and metastasis of pancreatic cancer is the main cause of its poor prognosis. Our preliminary studies demonstrated the long non-coding RNAs (lncRNAs) played an important role in this process. lncRNA-PATB is highly expressed in pancreatic cancer metastatic tissues, and promoted epithelial-mesenchymal transition (EMT) and metastasis of pancreatic cancer. However it is still unclear that how lncRNA-PATB regulated EMT and metastasis of pancreatic cancer and the detail mechanism has not been reported. Our preliminary data showed that lncRNA-PATB directly binds to SMAD3 leading to the activation of TGF-β signaling pathway. Therefore, we propose a novel mechanism that lncRNA-PATB directly interact with SMAD3 and activate the TGF-β signaling pathway and increase the expression of down-stream transcription factor Snail, promoting the EMT and metastasis of pancreatic cancer. In this proposal, the animal experiments, co-immunoprecipitation and luciferase reporter gene technology are used to elucidate the function and mechanism of lncRNA-PATB and how it activated the TGF-β signaling pathway by binding SMAD3, and will help to provide novel molecular targets for therapies against pancreatic cancer.

胰腺癌易侵袭转移是其预后差的主要原因。我们前期发表研究证实，长链非编码RNA (lncRNAs)在其中起重要作用，lncRNA-PATB在胰腺癌转移淋巴结中高表达，并促进胰腺癌上皮间质转化（EMT）和侵袭转移。然而，lncRNA-PATB如何调控胰腺癌EMT及转移，具体机制尚不清楚。近期预实验我们发现lncRNA-PATB与信号蛋白SMAD3结合，激活TGF-β信号通路。据此，我们提出lncRNA-PATB调控胰腺癌转移的新机制：lncRNA-PATB通过结合SMAD3介导TGF-β信号通路激活，提高下游转录因子Snail表达，诱导胰腺癌细胞EMT，促进胰腺癌侵袭转移。本项目拟通过动物实验、免疫共沉淀和荧光素酶报告基因等技术，阐明lncRNA-PATB在介导TGF-β/SMAD3信号通路促进胰腺癌侵袭转移中的关键作用及调控机制，为lncRNA-PATB作为胰腺癌靶向治疗新靶点提供科学依据。

胰腺癌易发生侵袭转移是其预后差的主要原因，既往研究表明，长链非编码RNA (lncRNAs)在其中起重要作用。在前期研究中，我们通过高通量测序鉴定了与胰腺癌转移相关的lncRNA-PATB。在本项目中，我们通过体外功能实验及体内动物实验验证lncRNA-PATB对胰腺癌的作用；通过RNA pull-down及RIP实验鉴定与lncRNA-PATB直接结合的关键分子；通过免疫共沉淀和荧光素酶报告基因等技术，阐明lncRNA-PATB的下游靶点及调控胰腺癌转移的分子机制。本项目证实了：在功能上，lncRNA-PATB过表达显著促进胰腺癌转移。在机制上，lncRNA-PATB与SMAD3直接结合，并通过募集蛋白激酶ERK介导SMAD3 磷酸化，进而激活TGF-β/SMAD3信号通路。TGF-β/SMAD3信号通路激活后通过上调下游转录因子Snail蛋白的表达，诱导胰腺癌发生EMT，进而促进胰腺癌的进展和转移。在临床上，lncRNA-PATB过表达与胰腺癌发生EMT及患者不良预后呈正相关。本项目阐明了lncRNA-PATB 在胰腺癌转移中的具体分子作用机制，为lncRNA-PATB作为胰腺癌治疗新靶点提供更充分的理论依据，并确定lncRNA-PATB在胰腺癌诊断中的临床意义。