新基因DDA1调控细胞周期蛋白Cyclin D1在肺癌发生与发展中的分子机制研究

项目名称： 新基因DDA1调控细胞周期蛋白Cyclin D1在肺癌发生与发展中的分子机制研究

项目编号： No.81472195

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 刘磊

作者单位： 四川大学

项目金额： 72万元

中文摘要： DDA1（DET1, DDB1 associated 1）基因是本实验室筛选重组人cDNA表达文库得到的新基因，并最早在GenBank注册，它从低等到高等生物中序列高度保守，推测可能在进化中有重要功能，文献报导DDA1是构成Cul4-E3泛素连接酶的核心亚基并参与泛素蛋白酶体降解，但它在肿瘤中的作用不清楚。我们研究发现与正常人肺组织相比，DDA1在肺癌组织中异常高表达，体内外实验发现上调DDA1的表达能够促进人肺癌细胞增殖，而抑制DDA1表达可以显著抑制细胞增殖，初步研究发现这种作用主要依赖于调控细胞周期蛋白CyclinD1表达及它上游PI3K/Akt信号通路,但详细的调控机制不清楚。因此，本课题将综合利用RNA干扰、细胞免疫荧光、CoIP-质谱鉴定、基因缺失或突变等技术，阐明DDA1调控肺癌细胞周期及增殖的分子机制，为深入研究DDA1基因功能及在肺癌发生、发展及预后中的作用奠定基础。

中文关键词： C05_气管；支气管；肺肿瘤；DDA1基因；细胞增殖；细胞周期蛋白D1；信号通路

英文摘要： DDA1 (DET1, DDB1 associated 1) is a new gene found by our colleagues through serological analysis of recombinant cDNA expression libraries (SEREX) technique, and first registered in GenBank database. It is speculated that DDA1 has significant functions because it shows greater sequence conservation in many species. Recent reports have shown that DDA1 is a core subunit of Cul4-E3 ubiquitin ligase and involved in ubiquition-proteasome pathway for degradation of target protein. However the function of DDA1 in tumor is uncertain. Our previously study shows that DDA1 expression level is abnormally up-regulated in lung tumor tissue compared with human normal lung tissue. In vitro and in vivo, up-regulation of DDA1 will promote cell proliferation, while suppressing DDA1 expression by RNAi will inhibit cell propagation. Our preliminary study found that the function of DDA1 is dependent on the regulation of the expression cell cycle protein Cyclin D1 and PI3K/Akt signaling pathway, whereas the mechanism of the regulation is unclear. In this project, we're focusing on analyzing how DDA1 regulates cell cycle in lung cancer and the molecular mechanism by applying RNA interference, immunofluorescence, Co-Immunoprecipitation & mass spectrometric analysis and gene deletion or mutant technique, hoping that this project could help us lay a theoretical foundation for further understanding the biological function of DDA1 and the function of DDA1 in lung cancer initiation, development and prognosis.

英文关键词： DDA1;cell proliferation;Cyclin D1;PI3K/AKT;lung cancer