类泛素小分子NEDD8作为新型抗肺癌分子靶点鉴定及其机制研究

Lung cancer badly endangers human health, which calls forto identifynovel anti-lung cancer target and develop new molecular inhibitors. Protein neddylation is athree-step enzymatic cascadewhich conjugates NEDD8 to targeted proteins and then regulates the conformation and function of thoestargeted proteins. Our preliminary study found that the key catalytic enzymes of Neddylation pathway and NEDD8 were highly expressed in lung cancer tissues and had a significant negative correlation with the prognosis of patients, suggesting that the over-activated Neddylation pathway promoted the development of lung cancer. Recent studies have revealed that even though small-molecule inhibitor of NEDD8-activating enzymeshowed significant antitumor effects on lung cancer,drug resistancewould be aroused by induced mutations of the targeted protein. Given the high expression level of NEDD8 in tumor tissue, we assumed NEDD8 as a new target of Neddylation pathway. To test this hypothesis, this project will examine the outcome of NEDD8 expression disorder on the malignant phenotypes of lung cancer cells and systematically evaluate the efficacy of targeting NEDD8 in the treatment of lung cancer, and then elucidate the underlying mechanism. This project will reveal the mechanism of high expression of NEDD8, identify NEDD8 as a new molecular target for lung cancer, and provide scientific basis for the development of novel drugs targeting Neddylation pathway.

肺癌严重危害人类健康，亟待鉴定新型抗肺癌分子靶标，研发靶向药物。蛋白Neddylation修饰是通过酶促催化反应将类泛素分子NEDD8连接到底物上并调控底物构象与功能的过程。我们前期研究发现，Neddylation修饰关键催化酶和NEDD8本身在肺癌内高表达，与患者预后呈显著负相关，提示Neddylation通路活化促进肺癌发生发展。近期研究表明，NEDD8活化酶特异性小分子抑制剂有显著抗肺癌效果，但可诱导靶标突变产生耐药。鉴于NEDD8在肺癌内高表达，我们提出NEDD8作为针对Neddylation通路抗肺癌新靶标的假设。为检验该假设，本项目将研究NEDD8表达失调对肺癌细胞恶性表型的影响，系统评价靶向NEDD8抗肺癌的疗效，并阐明其效应机制。项目成功完成将揭示NEDD8高表达的促癌机理，鉴定NEDD8为新型抗肺癌分子靶点，为靶向Neddylation通路新药研发和靶向治疗提供科学依据。

肺癌严重危害人类健康，亟待鉴定新型抗肺癌分子靶标。蛋白Neddylation修饰是通过酶促催化反应将类泛素分子发育下调蛋白8(NEDD8)连接到底物上并调控底物构象与功能的过程，该通路的活化可促进肺癌发生发展。本项目通过利用CRISPR/cas9等技术研究NEDD8表达对肺癌细胞恶性表型的影响及其机制，发现了（1）NEDD8在肺腺癌中过表达与患者总体生存率低相关；（2）敲除NEDD8在体内外均可触发肺腺癌细胞衰老或凋亡；（3）敲除NEDD8使Cullin-RING泛素连接酶（CRL）系统失活；（4）NEDD8可作为NAE（E1）的替代靶点。充分且成功地验证了“NEDD8作为针对Neddylation通路抗肺癌新靶标”的假设。此外，一些细胞衰老相关蛋白，如MAPK14、MAPK1和MAP2K1等在NEDD8基因敲除肺腺癌细胞中发生了改变，这表明这些蛋白可能在NEDD8缺失诱导细胞衰老中发挥了致因作用，因此我们将对衰老相关蛋白网络是否参与及影响NEDD8作用机制展开进一步的研究。总之，本项目着重研究了NEDD8在促进肺腺癌发生进展中的作用，揭示了NEDD8的深层促癌机制，为NEDD8作为NAE（E1）替代靶点以治疗肺腺癌的靶向策略提供了科学依据及理论支持。在未来的研究中，我们将进一步阐述NEDD8作为治疗肺腺癌靶点的更多潜在机制。