Nck and Crk in VEGF-Induced Endothelial Cells Migration

描述(由申请人提供)：从现有血管中生长新的毛细血管(血管生成)对于发育、组织再生和重塑是必不可少的。血管生成也有助于肿瘤生长和转移、糖尿病视网膜病变、类风湿性关节炎、牛皮癣和心血管疾病等病理条件。血管内皮生长因子(VEGF)是一种重要的促血管生成因子，通过与其受体KDR结合，刺激多种信号转导途径。血管内皮生长因子作为血管生成抑制的靶点受到关注的原因有很多，包括观察到通过多种实验方法阻断血管内皮生长因子的作用可以抑制动物模型中肿瘤的生长。 内皮细胞迁移是血管生成的关键步骤；然而，介导这一过程的细胞机制仍不清楚。我们的初步数据表明，细胞信号蛋白Nck和Crk在血管内皮生长因子诱导的细胞迁移中起重要作用。在血管内皮生长因子治疗后，这两种蛋白都被招募到KDR，尽管它们与受体的相互作用是间接的，并由FRS2支架蛋白介导。在血管内皮细胞中引入显性负性抑制物Crk或Nck对血管内皮生长因子诱导的与迁移相关的反应有显著影响。这些域名抑制了焦点复合体的周转，因为它们导致新的焦点复合体的形成减少，现有的焦点复合体的大小显著增加。伴随而来的是细胞粘附力的丧失。丹参还可阻断血管内皮生长因子诱导的F-肌动蛋白动力学改变。 我们计划通过提出三个具体目标来继续这些研究。AIM1侧重于阐明在血管内皮细胞生长因子处理后NCK和CrK如何被募集到细胞表面的分子方面。目的2详细研究了NCK调节细胞迁移的信号通路。目的3探讨Crk在血管内皮细胞生长因子诱导的细胞迁移中的作用。

DESCRIPTION (provided by applicant): The growth of new blood capillaries from existing vessels (angiogenesis) is essential for development, tissue regeneration and remodeling. Angiogenesis also contributes to pathologic conditions including tumor growth and metastasis, diabetic retinopathy, rheumatoid arthritis, psoriasis, and cardiovascular diseases. Vascular Endothelial Growth Factor (VEGF) is a critical pro-angiogenic factor that stimulates multiple signal transduction pathways through binding to its receptor KDR. VEGF has received attention as a target for angiogenesis inhibition for several reasons, including the observations that blocking VEGF's actions by several experimental approaches inhibits the growth of tumors in animal models. Endothelial cell migration is a crucial step in angiogenesis; however, the cellular mechanisms that mediate this process remain unclear. Our preliminary data indicate that the cell signaling proteins Nck and Crk play important roles in VEGF-induced cell migration. Both proteins are recruited to KDR after VEGF treatment, although their interaction with receptor is indirect and mediated by the FRS2 scaffolding protein. The introduction of dominant negative (DN) inhibitors of Crk or Nck into endothelial cells has dramatic effects on VEGF-induced responses related to migration. The DNs inhibit focal complex turnover as they lead to a loss in the formation of new focal complexes and a significant increase in the size of existing focal complexes. This is accompanied by a loss in cell adhesion. The DNs also blocked VEGF-induced changes in F-actin dynamics. We plan to continue these studies by proposing three Specific Aims. AIM1 focuses on clarifying molecular aspects of how Nck and Crk are recruited to the cell surface after VEGF treatment. AIM 2 examines in detail the signaling pathway by which Nck regulates cell migration. AIM 3 asks how Crk functions in VEGF-induced cell migration.