The connection between Notch signaling and VEGFR1 in angiogenesis

描述（由申请人提供）：血管生成是指从已有血管中形成新血管。在成人中，血管生成与伤口愈合、组织缺血、血管闭塞等事件有关，也与肿瘤生长和转移等病理过程有关。Notch信号是血管生成的关键调节因子，并与其他几种途径相互作用，包括血管内皮生长因子（VEGF）。本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）在血管生成刺激下内皮细胞的存活、发芽和增殖中所起的作用。此外，这些研究可能确定Notch信号在VEGFR1 +骨髓源性单核细胞中的可能作用及其对新生血管的贡献。利用人脐静脉内皮细胞（HUVECs）进行发芽、增殖、存活和脐带形成的体外实验，以研究Notch信号依赖于VEGFR-1的情况。从小鼠的骨髓和外周血中获取单核细胞，并使用体外表达分析和功能分析来研究这些细胞中Notch信号和VEGFR-1之间的联系。进一步的实验将评估骨髓动员使用血管生成刺激（如GM-CSF和VEGF-A）导致单核细胞Notch和VEGFR-1信号的变化。这些研究将表征Notch在血管稳态中的功能，并可能提示Notch在血管生成部位的骨髓细胞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调控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。这项研究的相关性是深远的。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，而且还可能使我们深入了解这个国家主要死亡原因的发病机制。由于血管畸形或不适当的血管发育导致了大量的医学疾病和疾病，因此了解Notch通路在这些过程中的作用对公共卫生至关重要。特别是与肿瘤生长和转移有关，研究Notch信号的机制对我国最常见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信号所涉及的各种疾病的诊断策略和治疗方法，并将为进一步的研究奠定基础，可以直接从实验室转化为临床。

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.