Maximization of anti-angiogenesis by thrombospondin-1

血小板反应蛋白-1 最大限度地抑制血管生成

• 批准号: 6969494
• 负责人: OLGA Valery VOLPERT
• 金额: $ 28.67万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6969494
• 关键词: angiogenesis inhibitors; antineoplastics; apoptosis; cell line; cell surface receptors; combination cancer therapy; confocal scanning microscopy; drug screening /evaluation; flow cytometry; growth inhibitors; human tissue; immunocytochemistry; laboratory mouse; neoplasm /cancer chemotherapy; neoplasm /cancer invasiveness; neoplastic growth; neutralizing antibody; peroxisome proliferator activated receptor; protein structure function; receptor binding; receptor expression; statistics /biometry; terminal nick end labeling; thiazoles; thrombospondins; vascular endothelium

DESCRIPTION (provided by applicant): Anti-angiogenic thrombospondin-1 (TSP1) binds CD36 receptor to trigger apoptosis in vascular endothelium. This causes a secondary signal via CD95/Fas, a death receptor expressed independent of TSP1 by remodeling endothelium. TSP1 increases CD95 cognate ligand, FasL, which binds inducer-generated Fas causing apoptosis. DI-TSP, a short TSP-derived inhibitory peptide generates identical signal. Thus the sensitivity to inhibitory TSP1/DI-TSP is limited by the availability of its primary (CD36), or secondary (CD95) signaling receptors. We aim to improve susceptibility to DI-TSP by modulating the levels of these rate-limiting signaling mediators. We will modulate CD36 using synthetic ligands of the PPARy nuclear receptor. CD95 we will alter with low-dose continuous (metronomic) chemotherapy. We propose to study: 1. The effects of the low-dose genotoxic agents on DI-TSP specific activity. We will measure Fas and FasL in human microvascular cells (HMVECs) treated with DI-TSP and/or low dose chemotherapy and compare the effects of DI-TSP and/or chemotherapy on the endothelial (EC) and cancer cell phenotype, Fas and FasL presentation, apoptosis and migration. Antibodies, Fas decoy receptor and metabolic inhibitors will be used to link CD95 increase with TSP1 augmented activity. 2. The effects of metronomic chemotherapy DI-TSP angiosuppression in vivo. Mice bearing bFGF-containing Matrigel plugs will be treated with DI-TSP and/or metronomic chemotherapy. The effect on vascularity, Fas and FasL expression, the extent of endothelia l cell apoptosis and pericyte recruitment will be measured. Antibodies, Fas decoy receptor and metabolic inhibitors will be used to link CD95 increase with TSP1 augmented activity. 3. The effects of thiazolinediones (TZDs, synthetic PPARy ligands) on CD36 expression and TSP1 anti-angiogenic activity. EC apoptosis, inhibition of migration, proliferation will be used to determine non-cytotoxic doses of troglitazone, rosiglitazone and pioglitazone, to achieve maximal CD36 increase. These doses will be tested in vivo in matrigel plug assay. CD36 neutralizing antibodies will be used to determine its contribution in vitro and in vivo. 4. The effect of TSP-based combination therapies on tumor growth and angiogenesis. TZDs and metronomic chemotherapy will be used alone and in combination with DI-TSP to block or delay the growth of invasive PC-3 or of less aggressive LNCaP prostate carcinoma. Tumor volume, angiogenesis, EC and non-EC apoptosis will be measured. Angiogenesis inhibitors comprise a new class of anti-cancer drugs. We showed that combining anti-angiogenics with chemotherapy offers possibility to significantly cut the dose and therefore the toxicity of chemotherapy while achieving substantial improvement in the efficacy of an anti-angiogenic. Such combined therapies present a promising new approach to the treatment of cancer and other angiogenesis dependent diseases.

描述（由申请人提供）：抗血管生成血小板反应蛋白-1 (TSP1) 结合 CD36 受体以触发血管内皮细胞凋亡。这会通过 CD95/Fas 产生次级信号，CD95/Fas 是一种通过重塑内皮独立于 TSP1 表达的死亡受体。 TSP1 增加 CD95 同源配体 FasL，FasL 与诱导剂产生的 Fas 结合，导致细胞凋亡。 DI-TSP 是一种短的 TSP 衍生抑制肽，可产生相同的信号。因此，对抑制性 TSP1/DI-TSP 的敏感性受到其初级 (CD36) 或次级 (CD95) 信号传导受体的可用性的限制。我们的目标是通过调节这些限速信号介质的水平来提高对 DI-TSP 的敏感性。我们将使用 PPARγ 核受体的合成配体来调节 CD36。我们将通过低剂量连续（节拍）化疗来改变 CD95。我们建议研究： 1.低剂量基因毒性剂对DI-TSP比活性的影响。我们将测量经 DI-TSP 和/或低剂量化疗处理的人微血管细胞 (HMVEC) 中的 Fas 和 FasL，并比较 DI-TSP 和/或化疗对内皮 (EC) 和癌细胞表型、Fas 和 FasL 的影响呈现、凋亡和迁移。抗体、Fas 诱饵受体和代谢抑制剂将用于将 CD95 的增加与 TSP1 增强的活性联系起来。 2.节拍化疗DI-TSP体内血管抑制作用。携带含 bFGF 基质胶塞的小鼠将接受 DI-TSP 和/或节拍化疗。将测量对血管分布、Fas和FasL表达、内皮细胞凋亡程度和周细胞募集的影响。抗体、Fas 诱饵受体和代谢抑制剂将用于将 CD95 的增加与 TSP1 增强的活性联系起来。 3. 噻唑啉二酮类（TZD，合成 PPARγ 配体）对 CD36 表达和 TSP1 抗血管生成活性的影响。 EC凋亡、抑制迁移、增殖将被用来确定曲格列酮、罗格列酮和吡格列酮的非细胞毒性剂量，以实现最大CD36增加。这些剂量将在基质胶塞测定中进行体内测试。 CD36 中和抗体将用于确定其在体外和体内的贡献。 4.基于TSP的联合疗法对肿瘤生长和血管生成的影响。 TZD 和节拍化疗将单独使用或与 DI-TSP 联合使用，以阻止或延迟侵袭性 PC-3 或侵袭性较低的 LNCaP 前列腺癌的生长。将测量肿瘤体积、血管生成、EC和非EC细胞凋亡。血管生成抑制剂是一类新型抗癌药物。我们表明，将抗血管生成药物与化疗相结合可以显着降低剂量，从而降低化疗的毒性，同时显着提高抗血管生成药物的疗效。这种联合疗法为治疗癌症和其他血管生成依赖性疾病提供了一种有前景的新方法。