NEDD8类泛素化修饰调控TβR/Smads/ANGPTL2通路参与非小细胞肺癌复发转移的机制研究

Tumor metastasis and postoperative recurrence are a significant problem associated with a poor prognosis in early non-small cell lung cancer (NSCLC) patients. Research have shown the overactivated neddylation pathway in the process of cancer recurrence/metastasis of NSCLC. But the targets and regulation mechanism of neddylationare still not clear. In our prophase research, the analysis results of the clinical specimens have shown the significant correlation of neddylation pathway with the recurrence of NSCLC or metastasis-associated angiopoietin-like protein (ANGPTL2) gene. Given that ANGPTL2 promoter region can be combined with a variety of transcriptional enhancement factor (such as TGF-β receptor TβR/Smads signal compounds, etc.), so we hypothesized that the overactivated neddylation pathway regulates the ANGPTL2 promoter transcription activity and its expression through modifying and affectting the complex stability of transcription enhancer TβR/Smads, and then promotes the recurrence/metastasis of NSCLC. In this study, we would investigate the role mechanism of neddylation pathway in the process of cancer recurrence/metastasis of NSCLC by in vitro, in vivo and clinical studies. We would screen and identify of target substrates of neddylation in TβR/Smads/ANGPTL2 pathway, and analysis the specific modification sites and the mechanism of transcription regulation. We hope that our research results can provide new therapeutic targets for the early diagnosis and the prevention of NSCLC recurrence/metastasis.

肿瘤复发转移严重影响早期非小细胞肺癌NSCLC患者预后。NEDD8类泛素化（Neddylation）通路在NSCLC复发转移中过度激活，但其机制仍不清楚。本项目临床标本发现Neddylation通路与NSCLC转移相关基因ANGPTL2呈正相关。鉴于ANGPTL2启动子区结合的转录增强子TβR/Smads受Neddylation通路的修饰，故推测激活的Neddylation通路调节TβR/Smads稳定性，提高ANGPTL2转录表达，促进NSCLC复发转移。本研究拟从临床标本、实验动物及细胞三个层面揭示Neddylation通路在NSCLC复发转移中机制，筛选并鉴定TβR/Smads/ANGPTL2通路中NEDD8的靶标底物、Neddylation修饰位点及ANGPTL2转录调控机制，为NSCLC复发/转移的早期诊断与防治提供新靶点。

肺癌是最常见的癌症类型，并且是全球范围内与肿瘤相关死亡的主要原因。核帽结合蛋白1（NCBP1）对于加帽的RNA处理和细胞内定位是必需的。有报道指出NCBP1沉默可以降低HeLa细胞的增殖，但其在非小细胞肺癌中的临床意义和潜在的分子机制仍不清楚。本研究中，发现NCBP1在肺腺癌组织及其细胞系中明显过表达。我们通过基因敲除及过表达实验，发现NCBP1促进了肺腺癌细胞的增殖，侵袭转移及上皮间质转化，并且发现CUL4B是NCBP1在肺腺癌中的下游靶基因。同时研究发现 NCBP1可通过与核帽结合蛋白3（NCBP3）相互作用上调CUL4B表达。 CUL4B沉默可以逆转了NCBP1诱导的肺腺癌的发生。基于这些发现，本研究提出了一个涉及肺腺癌的生物学功能的NCBP1/NCBP3/CUL4B调控轴模型，同时也为有关CUL4B是如何被激活并促进肺腺癌提出了一些新的见解。