EBV-miR-BART2-5p靶向m6A甲基转移酶METTL14调控EMT促进鼻咽癌侵袭转移的研究

目前m6A修饰的功能备受关注，其在鼻咽癌恶性进程中的作用尚未见报道。前期研究发现，EBV可能影响m6A修饰，该修饰进而参与鼻咽癌恶性进程；METTL14(M4)在鼻咽癌组织中表达下调，与TNM分期和EMT相关，M4过表达抑制鼻咽癌细胞发生EMT和迁移；M4是EBV-miR-BART2-5p(B2)的靶基因，B2过表达促进鼻咽癌细胞迁移；这提示B2靶向M4可能影响m6A修饰，进而调控EMT和侵袭转移。据此，拟开展以下研究：揭示鼻咽癌细胞和组织中m6A修饰水平；确证EBV对m6A修饰影响；探讨B2和M4在鼻咽癌EMT和侵袭转移中的作用，并确证B2上述功能可否由M4介导；miCLIP-seq和RNA-seq联用，筛选M4介导的m6A修饰的Gene-X及功能验证；揭示B2、M4及Gene-X等在鼻咽癌组织中表达谱、表达相关性和临床病理意义。预期成果有望揭示m6A修饰在鼻咽癌恶性进程中作用与机制。

In recent years, much attention has been paid to the biological functions of m6A mRNA modification at the RNA levels, however, the roles of m6A modification in the malignant progression of nasopharyngeal carcinoma (NPC) have not yet been reported. In our pilot study, we found that 1) the m6A modification may participate in NPC malignant progression and the m6A modification may be affected by EB virus；2) METTL14 expression in NPC tissues is significantly downregulated，and is related with the TNM stages and EMT of NPC；3) METTL14 overexpression inhibits EMT induction and migration of NPC cells；4) METTL14 is a target gene of EBV-miR-BART2-5p，and EBV-miR-BART2-5p overexpression promotes migration of NPC cells，suggesing that EBV-miR-BART2-5p regulates m6A modification in NPC cells by targeting METTL14，and thereby modulating EMT，invasion and metastasis in NPC. Aganist this background, this project intends to further carry out the following studies: 1) to reveal the levels of m6A modification in NPC cell lines and NPC tissues; 2) to explore the influences of EB virus on m6A modification levels; 3) to investigate the roles of EBV-miR-BART2-5p and its target gene METTL14 in NPC EMT, invasion and metastasis, and confirm whether the aforementioned functions of EBV-miR-BART2-5p can be mediated by its target gene METTL14; 4) to screen METTL14-mediated m6A modification in Gene-X by combined use of MeRIP-seq/m6A-seq or m6A-miCLIP-seq and RNA-seq technology, followed by functional verification; 5) to reveal the expression profile of EBV-miR-BART2-5p, METTL14 and Gene-X in NPC tissue samples, the expression correlation and clinical pathological significance, as well as the expression relationship between these genes and EMT-related genes. Expected achievement are anticipated to reveal the functions of m6A modification in NPC EMT, invasion and metastasis and underlying mechanisms, and provide valuable clues to discover EMT repressors.