OVEREXPRESSION OF MDM2 IN THE ETIOLOGY OF BREAST CANCER

乳腺癌病因中 MDM2 的过度表达

• 批准号: 6173171
• 负责人: Swati P. Deb
• 金额: $ 21.93万
• 依托单位: VIRGINIA COMMONWEALTH UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-20 至 2002-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6173171
• 关键词: 3T3 cells; MCF7 cell; RNA splicing; athymic mouse; breast neoplasms; carcinogenesis; carcinogenesis inhibitor; cell growth regulation; cellular oncology; complementary DNA; cyclin dependent kinase; cyclins; disease /disorder etiology; enzyme activity; flow cytometry; gene expression; neoplasm /cancer genetics; oncoproteins; protein binding; transfection

The long-term goal of this proposal is to understand the normal biological function of the hMDM2 oncoprotein and how its overexpression can induce tumorigenesis. The short-term objective is to test the hypothesis that hMDM2 induces cell cycle arrest, possibly by interacting with the cell cycle regulatory proteins. Inactivation of this function is one of the causes of tumorigenesis. The working hypotheses are based on the exciting observations that mMDM2 induces GO/G1 arrest in normal human diploid cells. Elimination of the growth arrest function enhances the tumorigenic potential of NIH3T3 cells. Furthermore, hMDM2 associates with two cell cycle regulatory proteins, cyclin E and p34 (cdc2). This proposal has four specific aims. 1) Consequence of hMDM2 overexpression in normal breast epithelial cells and breast tumor- derived cells will be analyzed. The domain(s) of hMDM2 needed to confer these growth alterations will be determined using deletion mutants of the oncoprotein. Identification of these domains will enable us to detect interactions of hMDM2 with other proteins (such as cyclin E) important for cellular growth regulator functions. 2) Different splice variants of mdm2 mRNA will be isolated from an hMDM2 overexpressing breast cancer cell line MCF-7 and a murine tumorigenic cell line 3T3DM (harbors amplified mdm2 gene). The growth regulatory properties of the proteins encoded by the different splice variants will be analyzed. 3) The consequence of hMDM2-cyclin E interaction on the cyclin E-associated kinase -activity and on cell growth will be determined. 4) Since hMDM2 associates with P34 (cdc2), how hMDM2 modulates the activation of p34 (cdc2) kinase activity and how this interaction modulates cell growth will be determined. Completion of these specific aims will elucidate a novel growth regulatory function of hMDM2 and how perturbation of that function leads to tumorigenesis.

该提案的长期目标是了解正常情况 hMDM2 癌蛋白的生物学功能及其过度表达 可诱发肿瘤发生。 短期目标是测试 假设 hMDM2 可能通过相互作用诱导细胞周期停滞 与细胞周期调节蛋白。 停用此功能 是肿瘤发生的原因之一。 工作假设基于 mMDM2 在正常情况下诱导 GO/G1 停滞的令人兴奋的观察结果 人类二倍体细胞。 消除生长停滞功能增强 NIH3T3 细胞的致瘤潜力。 此外，hMDM2 与两种细胞周期调节蛋白 cyclin E 和 p34 相关 (疾病预防控制中心2)。 该提案有四个具体目标。 1) hMDM2的后果 在正常乳腺上皮细胞和乳腺肿瘤中过度表达 将分析衍生的细胞。 hMDM2 需要赋予的域 这些生长改变将使用缺失突变体来确定 癌蛋白。识别这些域将使我们能够 检测 hMDM2 与其他蛋白质（例如细胞周期蛋白 E）的相互作用 对于细胞生长调节功能很重要。 2）不同的拼接 mdm2 mRNA 的变体将从 hMDM2 过表达中分离出来 乳腺癌细胞系MCF-7和小鼠致瘤细胞系3T3DM （含有扩增的 mdm2 基因）。 生长调节特性 将分析不同剪接变体编码的蛋白质。 3） hMDM2-cyclin E 相互作用对 cyclin E 相关细胞的影响 将确定激酶活性和对细胞生长的影响。 4) 自 hMDM2 与 P34 (cdc2) 相关，hMDM2 如何调节 p34 的激活 (cdc2) 激酶活性以及这种相互作用如何调节细胞生长 将被确定。完成这些具体目标将阐明 hMDM2 的新型生长调节功能及其扰动 功能导致肿瘤发生。