ROR长非编码RNA调控葡萄膜黑色素瘤转移的机制研究

Uveal melanoma (UM) is one of the most common intraocular malignant tumors in adults, the morbidity of UM accounted for the first place in intraocular cancer. Furthermore, the UM cells can easily metastatic through blood line. However, the precise mechanism of UM metastasis is still unknown. Long non-coding RNA ROR (lncRNA-ROR) is identified capable of reprogramming differentiated cells to induced pluripotent stem cells, and have the close correlation with breast cancers. Yet the precise mechanism underlying RoR regulation in tumors is remains unclear. Our previous study showed RoR had significantly higher expression in UM cells. The migratory ability of UM cells were remarkable reduced after RoR knockdown. The expression of TESC which acts as a regulatory target of RoR lncRNA decreased as well. Consistent with these findings, we will perform a series of experiments such as Chromatin immunoprecipitation, RNA immunoprecipitation, chromosome oligonucleotide precipitation, DNA Affinity Pull-down Assay to analysis the epigenetic modification mediated by ROR. Determine the precise mechanism underlying RoR regulation of TESC expression in UM as well as decipher the potential role of TESC in UM. This project can provide useful insights into the mechanism underlying ROR regulation in the metastasis of UM. Our study will serve as a theoretical underpinning for mechanism of UM metastasis.

葡萄膜黑色素瘤（UM）是最常见的眼内恶性肿瘤，极易通过血行转移至全身重要器官。然而，UM的转移机制尚未明确。ROR是具有调控干细胞再生能力的重要长非编码RNA（lncRNA），研究表明ROR异常表达与乳腺癌等肿瘤发生存在密切关系，然而lncRNA-ROR在肿瘤发生中的致病机理仍不清楚。项目组前期研究发现lncRNA-ROR高表达于UM，沉默lncRNA-ROR表达降低UM细胞转移能力，并导致其下游靶基因TESC表达下调。在此基础上，本项目拟进一步通过染色质免疫共沉淀、染色体寡核苷酸沉淀、RNA免疫共沉淀、DNA亲和吸附洗脱法等分子生物学技术手段，深入分析ROR介导的表观遗传修饰，揭示UM中lncRNA-ROR调控TESC的表达机理，并阐明TESC在UM发生中的关键作用。本项目的开展将有利于深入理解lncRNA-ROR在UM转移中的调控机制，期望为UM转移机制研究提供理论基础和新思路。

葡萄膜黑色素瘤（Uveal Melanoma, UM）是成人最常见的眼内原发性恶性肿瘤，其发病率占眼内肿瘤的首位。此瘤的恶性程度高，且极易通过血行转移至全身重要器官，以往研究认为UM 的发生和黑色素细胞相关成熟调控蛋白及其细胞周期通路有关，但UM的转移机制尚未明确。本项目研究从表观遗传方向，以长非编码RNA ROR（lncRNA-ROR）为切入点，通过基因芯片技术、染色质免疫共沉淀、RNA免疫共沉淀等分子生物学与表观遗传学的技术手段，明确lncRNA-ROR在UM发生中的重要作用，探究lncRNA-ROR介导下游靶基因TESC表观遗传修饰在UM转移能力变化中的关键作用，进一步分析TESC基因在UM转移中的重要功能，阐明UM发生中lncRNA-ROR调控TESC基因表达的作用模式。本项目研究发现，在UM中lncRNA-ROR高表达，利用shRNA靶向敲除lncRNA-ROR，发现肿瘤细胞转移能力显著下降；基因芯片结果和体外实验进一步明确肿瘤细胞中TESC基因是lncRNA-ROR调控的关键靶基因，促进肿瘤细胞转移。通过一些列表观遗传及分子实验，项目组成员采用“诱饵效应”新思路，发现lncRNA-ROR通过与组蛋白甲基化酶G9A竞争性结合TESC启动子，导致TESC在肿瘤细胞中高表达，促进肿瘤细胞增殖、迁移、成瘤能力。研究发表在权威杂志《Genome Biology》，入选杂志发表当期特别评论研究，并赋予“F1000论文”称号，评价该成果：“揭示肿瘤发生新机制，是肿瘤研究的范例”。