The connection between Notch signaling and VEGFR1 in angiogenesis

描述（由申请人提供）：血管生成是从先前存在的血管形成新血管。在成人中，血管生成与诸如伤口愈合、组织缺血、血管闭塞的事件相关，并且还与诸如肿瘤生长和转移期间的病理过程相关。Notch信号传导是血管生成的关键调节因子，并与包括血管内皮生长因子（VEGF）在内的几种其他途径相互作用。该提案的总体目标是进一步确定Notch信号通路在血管生成中的作用，以及Notch靶基因，特别是VEGF受体-1（VEGFR-1）在响应血管生成刺激的内皮细胞存活、发芽和增殖中的作用。此外，这些研究可能定义Notch信号在VEGFR 1+骨髓来源的单核细胞中的可能作用及其对新血管形成的贡献。将使用人脐静脉内皮细胞（HUVEC）进行发芽、增殖、存活和脐带形成的体外试验，以研究Notch信号传导依赖于VEGFR-1的背景。将从小鼠收获来自骨髓和外周血的单核细胞，并使用体外表达分析和功能测定来研究这些细胞中Notch信号传导和VEGFR-1之间的联系。进一步的实验将评估由于使用血管生成刺激物如GM-CSF和VEGF-A的骨髓动员而导致的单核细胞中Notch和VEGFR-1信号传导的变化。这些研究将描述Notch在血管稳态中的功能，并可能表明Notch在血管生成部位骨髓细胞的募集和功能中的新作用。该项目的长期目标是确定Notch介导的VEGFR-1调节在肿瘤血管生成等病理过程中的作用，并确定潜在的治疗靶点。这项研究的意义是深远的。它不仅将提供有关具有广泛和重要功能的信号通路的基本知识，而且还可能导致对该国主要死亡原因的发病机制的深入了解。由于血管畸形或不适当的血管发育导致的医学障碍和疾病的丰富性，了解Notch途径在这些过程中的作用对公共卫生至关重要。特别是由于Notch信号通路与肿瘤的生长和转移密切相关，因此Notch信号通路的研究对我国最流行和最致命的疾病之一具有深远的意义。这些研究可能直接影响Notch信号转导所涉及的各种疾病的诊断策略和治疗方法，并将为进一步研究奠定基础，这些研究可以直接从实验室转化为临床研究。

DESCRIPTION (provided by applicant): Angiogenesis is the formation of new blood vessels from preexisting ones. In adults, angiogenesis is associated with events such as wound healing, tissue ischemia, vessel occlusion, and also with pathological processes such during tumor growth and metastasis. Notch signaling is a critical regulator of angiogenesis and interacts with several other pathways, including that of vascular endothelial growth factor (VEGF). The overall objective of this proposal is to further define the Notch signaling pathway in angiogenesis and the role that Notch target genes, specifically VEGF receptor-1 (VEGFR-1), play in the survival, sprouting, and proliferation of endothelial cells in response to angiogenic stimuli. In addition, these studies may define a possible role for Notch signaling in VEGFR1 + bone marrow-derived monocytes and their contribution to neovascularization. In vitro assays for sprouting, proliferation, survival, and cord formation using human umbilical vein endothelial cells (HUVECs) will be performed to investigate the contexts in which Notch signaling is dependent on VEGFR-1. Monocytes from bone marrow and peripheral blood will be harvested from mice and used to investigate the connection between Notch signaling and VEGFR-1 in these cells using in vitro expression analysis and functional assays. Further experiments will assess changes in Notch and VEGFR-1 signaling in monocytes as a result of bone marrow mobilization using angiogenic stimuli such as GM-CSF and VEGF-A. These studies will characterize Notch function in vascular homeostasis and may suggest a novel role for Notch in recruitment and function of bone marrow cells at angiogenic sites. The long-term objective of this project is to determine the role of Notch-mediated regulation of VEGFR-1 in pathological processes such as tumor angiogenesis and to identify potential therapeutic targets. The relevance of this research is profound. Not only will it provide fundamental knowledge about a signaling pathway with widespread and significant functions, but it may also lead to insight into the pathogenesis of leading causes of death in this country. Given the abundance of medical disorders and diseases that are the result of vascular malformation or inappropriate blood vessel development, understanding the role of the Notch pathway in these processes is of tremendous importance to public health. Particularly as it is related in tumor growth and metastasis, studies of the mechanism of Notch signaling has far-reaching implications in one of the most prevalent and fatal diseases in our nation. These studies may directly influence the diagnostic strategies and therapeutic approaches for various diseases in which Notch signaling is involved and will constitute a foundation for further research that can directly translate from bench to bedside.