THE ROLE OF NEDD4-1 IN IGF-1R SIGNALING

NEDD4-1 在 IGF-1R 信号转导中的作用

• 批准号: 8316173
• 负责人: Junran Zhang
• 金额: $ 32.58万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-08 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8316173
• 关键词: Binding; Biological Markers; Cancer Cell Growth; Cancer Patient; Cell Proliferation; Cell Survival; Cell physiology; Cells; Clinical Trials; Cultured Cells; DNA; Data; Development; Drug Delivery Systems; Embryonic Development; Fc Receptor; Goals; Growth; Guidelines; Human; Insulin-Like Growth Factor I; Knock-out; Knowledge; Ligase; Maintenance; Malignant Neoplasms; Metabolism; Modeling; Molecular; Mus; Oncogenic; Outcome; PTEN gene; Phosphorylation; Play; Proteins; Receptor Inhibition; Receptor Signaling; Regulation; Research; Role; SS DNA BP; Screening procedure; Signal Pathway; Signal Transduction; Testing; Ubiquitination; Work; Xenograft Model; base; cancer cell; cancer therapy; cell growth; improved; insight; new therapeutic target; novel; novel strategies; overexpression; protein expression; receptor; replication factor A; response; treatment planning; tumor; tumorigenesis

DESCRIPTION (provided by applicant): NEDD4-1 is an E3 ubiquitination ligase that is frequently over-expressed in human cancers. NEDD4-1 plays an important role in tumorigenesis. Although it has been suggested that NEDD4-1 functions as an oncogenic protein by facilitation of Akt activation, the molecular mechanisms by which NEDD4-1 activates Akt remain largely unknown. We found that NEDD4-1 activates Akt via regulation of IGF-1R signaling. Strikingly, we also found that activation of Akt by NEDD4-1 is negatively regulated by replication protein A (RPA), a single strand DNA (ssDNA) binding protein which is generally believed to play a critical role in DNA metabolism. Thus, we are proposing a study to test the central hypothesis that NEDD4-1 plays a role in cell proliferation via activation of IGF-1R signaling and this pathway is inhibited by RPA. Therefore, growth of cells overexpressing NEDD4-1 is specifically suppressed by IGF-1R inhibition through IGF-1R antibody and/or RPA. Three interrelated specific aims are proposed to test our hypothesis. Aim 1 will identify the role of NEDD4-1 in cell proliferation via regulation of IGF-1R signaling. Aim 2 will delineate how NEDD4-1 dependent IGF-1R signaling is regulated by RPA. Aim 3 will determine the antitumor activity of blocking IGF-1R signaling in cells over-expressing NEDD4-1. We anticipate to (1) define the molecular mechanisms by which NEDD4-1 promotes cell proliferation via regulation of IGF-1R signaling; (2) identify a novel function of RPA in suppression of IGF-1R signaling via interaction with NEDD4-1; (3) find that the growth of cancer cells over-expressing NEDD4-1 can be specifically targeted by IGF-1R inhibition through RPA and/or IGF-1R antibody. The expected results will fundamentally advance our understanding of the molecular mechanism underlying NEDD4-1 associated cancer development. In addition, identification of a novel function of RPA in suppression of IGF-1R signaling will facilitate the development of novel drugs targeting NEDD4-1 or IGF-1R. Moreover, the expected result will improve guidance for cancer treatment plans based on better predictions of tumor response to IGR-1R inhibition by identification of cancer patients with NEDD4-1 over-expression.

描述（由申请人提供）：NEDD4-1是E3泛素化连接酶，在人类癌症中经常过表达。NEDD4-1在肿瘤发生中起重要作用。虽然有研究表明NEDD4-1通过促进Akt激活而发挥致癌蛋白的作用，但NEDD4-1激活Akt的分子机制仍不清楚。我们发现NEDD4-1通过调节IGF-1R信号激活Akt。引人注目的是，我们还发现NEDD4-1对Akt的激活受到复制蛋白A （RPA）的负调控，RPA是一种单链DNA （ssDNA）结合蛋白，通常被认为在DNA代谢中起关键作用。因此，我们提出了一项研究来验证NEDD4-1通过激活IGF-1R信号通路在细胞增殖中发挥作用，而这一途径被RPA抑制的中心假设。因此，IGF-1R通过IGF-1R抗体和/或RPA特异性抑制过表达NEDD4-1细胞的生长。提出了三个相互关联的具体目标来检验我们的假设。目的1将确定NEDD4-1通过调节IGF-1R信号传导在细胞增殖中的作用。目的2将描述依赖NEDD4-1的IGF-1R信号如何被RPA调节。Aim 3将确定阻断过表达NEDD4-1细胞中IGF-1R信号的抗肿瘤活性。我们期望(1)确定NEDD4-1通过调节IGF-1R信号传导促进细胞增殖的分子机制；(2)发现RPA通过与NEDD4-1相互作用抑制IGF-1R信号的新功能；(3)发现过表达NEDD4-1的癌细胞可以通过RPA和/或IGF-1R抗体特异性抑制IGF-1R的生长。预期的结果将从根本上推进我们对NEDD4-1相关癌症发展的分子机制的理解。此外，发现RPA抑制IGF-1R信号的新功能将有助于开发针对NEDD4-1或IGF-1R的新型药物。此外，通过鉴定NEDD4-1过表达的癌症患者，更好地预测肿瘤对IGR-1R抑制的反应，预期的结果将改善癌症治疗计划的指导。