TARGETING ANGIOGENESIS WITH TOXIN-VEGF FUSION PROTEINS

描述：(申请人描述) 该项目的总体目标是开发一种具有商业可行性的细菌。 毒素-血管内皮细胞生长因子融合蛋白用于选择性 靶向血管生成部位的内皮细胞，主要是在固体中 肿瘤和不断增长的转移。血管内皮生长因子与血管内皮细胞的相互作用 在血管内皮细胞过度表达的特异性KDR/Flk-1受体 血管生成的部位与其在静止内皮细胞上的表达有关。 在这个项目的第一阶段，我们已经构建、表达和纯化了两个 新型融合蛋白SLT-VEGF/L和SLT-VEGF/S分别含有， 志贺样毒素I(SLT)A亚基及其功能片段 A亚基的。系统性红斑狼疮导致出血 结肠炎和溶血性尿毒症综合征通过损伤内皮细胞提示 内皮细胞对SLT特别敏感。 SLT-血管内皮生长因子/L和SLT-血管内皮生长因子/S蛋白选择性抑制内皮细胞生长 高表达KDR/Flk-1受体的细胞IC-50为0.15 nM。处于低谷 纳米浓度SLT-血管内皮细胞生长因子/L对内皮细胞的细胞毒作用 过表达KDR/Flk-L受体。然而，这些蛋白质不会影响 生长的低数量KDR/Flk-L受体的内皮细胞，静止 内皮细胞，以及正在生长的非内皮细胞。这些结果提供了一个 SLT-血管内皮细胞生长因子融合蛋白二期体内检测的基本原理 血管生成的选择性抑制剂。我们还将检测SLT-VEGF 蛋白质可能通过增强递送与其他抗肿瘤药物协同作用 通过损伤肿瘤内皮或通过创造低氧条件 生物还原疗法。最后，我们将优化SLT-VEGF融合蛋白 要实现高水平的表达、活性和稳定性， 临床前和临床试验所必需的。 建议的商业应用： 这项研究的潜在商业应用简要概述：抑制血管生成但不影响正常血管内皮细胞或正常细胞的血管内皮生长因子-毒素融合蛋白将成为治疗血管生成依赖的病理的商业产品。

DESCRIPTION: (Applicant's Description) The overall goal of this project is to develop a commercially viable bacterial toxin-VEGF (vascular endothelial growth factor) fusion protein for selective targeting of endothelial cells at sites of angiogenesis, primarily in solid tumors and growing metastases. VEGF interacts with the endothelial cell specific KDR/flk-1 receptor that is overexpressed in endothelial cells at the sites of angiogenesis relative to its expression on quiescent endothelium. In Phase I of this project we have constructed, expressed and purified two novel fusion proteins, SLT-VEGF/L and SLT-VEGF/S which contain, respectively, The A subunit of Shiga-like toxin I (SLT) and a functionally active fragment of the A subunit. SLT causes hemorrhagic colitis and hemolytic uremic syndrome by damaging endothelial cells suggesting that endothelial cells are particularly sensitive to SLT . SLT-VEGF/L and SLT-VEGF/S proteins selectively inhibit growth of endothelial cells overexpressing KDR/flk-1 receptors with IC-50 of 0.15 nM. At low nanomolar concentrations SLT-VEGF/L is cytotoxic for endothelial cells overexpressing KDR/flk-l receptors. However, these proteins do not affect growing endothelial cells with low numbers of KDR/flk-l receptors, quiescent endothelial cells, and growing non-endothelial cells. These results provide a rationale for Phase II in vivo testing of SLT-VEGF fusion proteins as highly selective inhibitors of angiogenesis. We will also test whether SLT-VEGF proteins may synergize with other antitumor drugs by enhancing delivery through damaged tumor endothelium or by creating hypoxic conditions for bioreductive therapeutics. Finally, we will optimize SLT-VEGF fusion proteins to achieve high levels of expression, activity, and stability that are necessary for preclinical and clinical trials. PROPOSED COMMERCIAL APPLICATION: A brief summary of the potential commercial applications of the research: VEGF-toxin fusion proteins that inhibit angiogenesis but do not affect normal endothelium or normal cells will be commercial products for therapy of angioaenesis-dependent pathologies.