长链非编码RNA介导的TGF-β调控网络在维持肝癌细胞干性及转移潜能中的表观遗传学作用机制研究

At present , hepatocellular carcinoma (HCC) still is one of the most common and the highest death rate cancers all around the world, and the material cause of the poor prognosis of HCC patients is the high rates of recurrence and metastasis of HCC . Some studies show that the existence of cancer stem cells results in the high rates of recurrence and metastasis of many cancers ,so finding the related signal pathway of the stem cell of liver cancer is helpful to the early diagnosis and treatment of HCC patients . TGF-β induced epithelial-mesenchymal transition(EMT), which involves the regulation of organ development, the stem of cell and the metastasis of tumor cells, is the external performance of the stem features of liver cancer. Based on the above analysis, we have completed lncRNA Chip assay of the EMT cells and the human liver tissue. We have screened some long noncoding RNAs , such as PVT1, ATB, NEAT1 and so on , which mediate TGF-βnetwork and are related with the prognosis of HCC patients. On this basis, we plan to use some technologies ,such as transcription factor prediction, RIP-seq, RNA pulldown and so on ,to study deeply the upstream and downstream regulatory mechanisms of the above functional lncRNAs. Furthermore, by integrating stem cell Chip data, we are looking for more the early molecular events of HCC, in order to complete the lncRNA-mediated TGF-β network , find more sensitive detection index, and identify new targets for the treatment of HCC patients. The above content still have not been reported.

肝细胞肝癌依然是世界范围内最常见和致死率最高的肿瘤之一，肝癌的高复发和高转移率是导致肝癌预后不佳的主要原因，有研究显示肿瘤干细胞的存在导致了多种肿瘤的高复发和高转移，寻找肝癌的干细胞相关信号通路有助于肝癌早期诊断和治疗。TGF-β诱导的上皮-间质转化（EMT）同时涉及器官发育、细胞干性、肿瘤细胞转移的调控，是肝癌细胞干性特征的外在表现。本课题组在前期研究中完成了肝癌细胞EMT模型、人胎肝-成肝组织的lncRNA芯片检测，筛选到PVT1、ATB等长链非编码RNA介导了TGF-β调控网络，与肝癌患者预后相关，基于此，本课题拟利用转录因子预测、RIP-seq等技术对上述功能性lncRNA的上、下游调控机制进行深入挖掘，并整合干细胞芯片数据，寻找更多肝癌发生早期的分子事件，完善lncRNA介导的TGF-β调控网络，为肝癌诊断找到更敏感检测指标，为肝癌治疗确定新靶点，以上内容经检索无报道。

肝细胞肝癌是世界范围内常见和致死率高的肿瘤之一，其中，肝癌干细胞的存在，及肝癌的肝内和肝外转移是HCC高复发率及较差预后的主要原因。有研究显示肿瘤干细胞的存在导致了多种肿瘤的高复发和高转移，寻找肝癌的干细胞相关信号通路有助于肝癌早期诊断和治疗。因此本课题建立了构建了DEN诱导的小鼠肝癌模型，收集了小鼠发育不同阶段的肝脏样本，收集了人胎儿肝脏样本和正常人肝脏样本，通过长链非编RNA（lncRNA）芯片的高通量筛选并结合生物信息学分析，获得了参与调控肝癌细胞EMT过程、涉及肝脏发育和肝癌发生发展的lncRNA，并深入地研究了lncRNA Ptn-dt及lncRNA MIR4435-2HG在肝癌发生发展中的作用及其表观遗传学调控机制。研究中发现，lncRNA Ptn-dt在小鼠肝癌和胎肝组织中高表达，可以促进肝癌细胞在体内和体外的增殖能力，进一步的研究证实，Ptn-dt通过与HuR间的相互作用下调miR-96的表达，进而促进Ptn的功能，最终起到推动肝癌发生发展的功能。此外，本课题组在研究过程中还发现，癌胚性lncRNA MIR4435-2HG在肝癌中由METTL3异常激活，可通过结合NOP58促进肝癌细胞增殖和蛋白合成。本课题的研究为阐明lncRNA在肝癌发生发展中的作用，挖掘肝癌早期诊断和治疗的有效靶点提供了思路。