In situ detection of apoptosis in tumor endothelial cells

说明：（申请人提供） 靶向肿瘤血管系统的药物具有巨大的抗癌潜力 因为它们似乎不会诱导耐药性。然而，在这方面， 这些药物是细胞抑制性的而不是细胞毒性的，这就形成了一组独特的 药物疗效评价的问题，因为经典的措施， 肿瘤“反应”可能是无效的。尤其重要的是， 确定其生物作用机制并开发新方法， 在原发性患者组织标本中检测这些效应。为此我们 已经开发出一种技术，可以检测垂死的肿瘤， 我们的初步结果强烈表明，抗血管生成， 药物诱导肿瘤内皮细胞凋亡。整体 本研究的目的是确定内皮细胞凋亡是否 是用抗血管生成药物治疗的肿瘤中的敏感标志物或功效 可以区分对这些药物有反应的患者和 谁不喜欢为此，我们建议：（1）明确具体的作用 在体外维持内皮细胞活力的“存活”途径。 细胞将暴露于生长因子撤除或VEGF受体 拮抗剂，以及对先前参与细胞内信号传导途径的影响。 将评估存活率（即AKT）。我们还将从这些细胞中分离mRNA， 细胞，并分析在以下情况下与糖尿病相关的基因表达的变化 VEGF撤药。(2)确定内皮细胞凋亡在 原位肿瘤模型。携带人胰腺、结肠或 前列腺肿瘤将用试验药物治疗， 通过CD 31/TUNEL染色测量肿瘤内皮细胞凋亡。（三） 描述内皮细胞凋亡在抗血管生成作用中的作用 患者的治疗。内皮细胞凋亡水平 用抗血管生成剂治疗的患者将与肿瘤 血流变化和反应的放射学测量。这些研究 将使我们能够快速确定肿瘤内皮细胞凋亡 可用作接受本品治疗的患者的临床反应的替代品 一类新型抗癌剂。

Description: (provided by applicant) Agents that target tumor vasculature have tremendous potential as anti-cancer therapies because they do not appear to induce drug resistance. However, these agents are cytostatic rather than cytotoxic, which poses a unique set of problems for the evaluation of drug efficacy because classical measures of tumor "response" may not be valid. It will be especially important to identify their biological mechanisms of action and to develop new methods to detect these effects in in primary patient tissue specimens. To this end, we have developed a technique that allows for the detection of dying tumor endothelial cells, and our preliminary results strongly suggest that antiangiogenic agents induce apoptosis in tumor endothelial cells. The overall goal of the present studies is to determine whether endothelial cell apoptosis is a sensitive marker or efficacy in tumors treated with anti-angiogenic therapies that can distinguish patients who respond to these drugs from those who do not. To this end, we propose to: (1) Define the role of specific "survival" pathways in the maintenance of endothelial cell viability in vitro. Cells will be exposed to growth factor withdrawal or VEGF receptor antagonists, and effects on signaling pathways previously implicated in cell survival (i.e. AKT) will be evaluated. We will also isolate mRNA from these cells and analyze changes in apoptosis-associated gene expression following VEGF withdrawal. (2) Determine the role of endothelial cell apoptosis in orthotopic tumor models. Nude mice bearing human pancreatic, colon, or prostate tumors will be treated with investigational agents, and effects on tumor endothelial cell apoptosis will be measured by CD31/TUNEL staining. (3) Characterize the role of endothelial cell apoptosis in the effects of antiangiogenic therapies in patients. Levels of endothelial cell apoptosis in patients treated with anti-angiogenic agents will be correlated with tumor blood flow changes and radiographic measurements of response. These studies will allow us to rapidly determine whether tumor endothelial cell apoptosis can be used as a surrogate for clinical response in patients treated with this class of novel anti-cancer agents.