HNF4α-miR-541-自噬相关基因调控通路在肝癌中的作用

项目名称： HNF4α-miR-541-自噬相关基因调控通路在肝癌中的作用

项目编号： No.81502077

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 医药、卫生

项目作者： 许文萍

作者单位： 中国人民解放军第二军医大学

项目金额： 18万元

中文摘要： 肝细胞核因子4α（HNF4α）可诱导肝癌分化。我们前期研究发现它可转录调控DLK1-DIO3印记基因区上的miR-379-656簇，对该簇miRNA进行功能研究发现miR-541抑制肝癌增殖的作用最强，且其在肝癌组织和成球细胞中下调。多种软件均预测自噬相关基因ATG2和RAB1B为其靶基因，报告基因实验证实它可结合二者的3’非翻译区。既往对miR-541的研究较少，其对肝癌的作用亦无报道。本研究将检测肝病患者及肝癌患者血清miR-541表达，分析其作为诊断标志物的可能性，检测肝癌患者肝脏和血清miR-541表达，分析其与临床恶性表型和预后的关系；研究其在体内外对肝癌细胞恶性生物学行为的作用；探讨miR-541是否通过调控RAB1B和ATG2影响自噬以及HNF4α是否通过调控miR-541影响自噬，从而首次探明HNF4α、miR-541、自噬相关调控通路在肝癌中的作用，为其诊治提供新靶点。

中文关键词： 肝和肝内胆管肿瘤；肝细胞核因子；微小RNA；自噬；自噬相关基因

英文摘要： Hepatocyte nuclear factor 4α (HNF4α) could induce the differentiation of hepatocellular carcinoma (HCC). Our previous study shown that HNF4α transcriptionally up-regulated the expression of miR-379-656 cluster in the DLK1-DIO3 imprinted region. Functional assays demonstrated that, of these miRNAs within the cluster, miR-541 displayed the strongest inhibitory effect on the proliferation of hepatocellular carcinoma (HCC) cells. Moreover, the expression of miR-541 was significantly reduced in HCC tissues and mammospheres. Furthermore, several algorithm predictions indicated autophagy related genes ATG2A and RAB1B as potential targets of miR-541.The following reporter assays demonstrated that miR-541 could bind to the 3’ untranslation region of RAB1B and ATG2A. To date, little has been known about the function of miR-541. Moreover, the effect of miR-541 on HCC also remains unknown. Based on these findings, the present study aims to 1) detect the level of miR-541 in the serum of chronic liver diseases patients and HCC patients and investigate whether it can be used as a diagnostic marker; detect the expression of miR-541 in the liver tissues and serum from HCC patients and analyze its relationship with the clinical malignant phenotype and prognosis of patients; 2) investigate the effects of miR-541 on the malignant biological behavior of HCC cells both in vitro and in vivo; 3) verify the effect of miR-541 on autophagy through regulating ATG2A and RAB1B; 4) study whether HNF4α could affect autophagy by regulating miR-541. Taken together, the research will reveal the consequence of HNF4α-miR-541-ATG2A/RAB1B pathway dysregulation in the development of HCC, which may help to unveil the underlying molecular mechanism and provide novel targets for the diagnosis and treatment of HCC.

英文关键词： Liver cancer and intrahepatic bile duct tumor;hepatocyte nuclear factor;microRNA;autophagy;autophagy-related gene