化学致癌物DNP活化超增强子调控MICAL2促进鼻咽癌转移的分子机制研究

Nasopharyngeal carcinoma (NPC) is a head and neck cancer with high morbidity in the south of China，NPC metastasis impacts NPC therapy. Our previous works found that NPC specific factor, Dinitrosoperazine (DNP) activated NPC super enhancer (SE) and H3K27ac of molecule interacting with CasL2 (MICAL2), also found that MICAL2 participates in epithelial-mesenchymal transition (EMT) regulation, and molecule simulation indicated that DNP interactes with SE211. We speculate that DNP may activate super enhancer to regulate MICAL2 expression, mediate NPC cell EMT and promote NPC metastasis. In this study, ① CHIP-seq and molecule simulation are used to screen the super enhancers of NPC metastasis. ② Gene transfection and shRNA technology are used to investigate that DNP regulates MICAL2 expression through super ehancer. ③ It is probed that DNP induces MICAL2 expression to regulate EMT of NPC cell . ④ Clinical study on MICAL2 expression in NPC samples and sera are used to confirmed that MICAL2 expression is associated with NPC development，metastasis and prognosis. ⑤Nude mice model of NPC metastasis is used to verify that DNP promotes NPC metastasis though regulating MICAL2/EMT.This study will clarify that NPC specific pathogenic factor DNP promotes NPC metastasis through activating super enhancer to regulate MICAL2 signal pathway. This will provides a novel clue for NPC metastasis research.

鼻咽癌(NPC)是我国南方发病率极高的头颈恶性肿瘤，转移严重影响其有效治疗。前期研究发现致病因子DNP活化超增强子（SE）和诱导MICAL2-H3K27ac，还发现MICAL2参与调控细胞EMT，分子动态模拟发现DNP与SE211结合。由此推断：DNP激活超增强子调控MICAL2表达介导细胞EMT，促进NPC转移。本项目拟进行: ①CHIP-seq和分子动态模拟筛选DNP介导NPC转移的超增强子。②基因转染和shRNA干扰技术探讨DNP通过超增强子调控MICAL2表达。③探讨DNP诱导MICAL2表达调控细胞EMT，促进细胞侵袭转移。④临床研究探讨MICAL2表达与NPC发生发展、转移和预后的相关性。⑤动物实验验证DNP介导MICAL2促进NPC转移。本项目将阐明DNP通过SE-MICAL2-EMT-metastasis促进NPC转移的机制，为NPC转移机理研究提供科学的理论依据.

鼻咽癌好发于我国南方地区、东南亚和北非等地区， 我省是鼻咽癌高发地区之一。在我省鼻咽癌发病率高、治疗生存率较低，严重影响我省人们的健康和社会经济发展。迫切需要探索新的生物标志物为鼻咽癌患者提供新的诊断方法和新的治疗方案，实现鼻咽癌的有效治疗。本研究通过对高转移鼻咽癌细胞S18和低转移鼻咽癌细胞S26进行表观遗传学分析，用H3K27ac CHIP-Seq筛选鼻咽癌细胞转移特异性SE，采用GRO-Seq进一步鉴定特异性SE转录生成的seRNA。研究数据表明，转移特异SE转录生成seRNA LOC100506178在高转移鼻咽癌细胞S18及5-8F中显著高表达,而在对应的低转移鼻咽癌细胞S26及6-10B中表达量显著降低，二亚硝基哌嗪促进鼻咽癌细胞转移且介导seRNA LOC100506178高转录。此外，本研究还探讨seRNA LOC100506178对鼻咽癌细胞侵袭转移的影响，并阐明其调控鼻咽癌EMT作用和分子机制，获得了一些原创性的研究成果，为阐明鼻咽癌转移的分子机制和寻找转移预测标志物提供理论依据。seRNA LOC100506178有望成为鼻咽癌的有效治疗靶点，以改善患者预后，提高生存率，具有重要临床意义和应用前景。具有一定的原始创新性。通过本项目完成培养研究生3名，其中博士研究生1名。发表学术论文6篇。