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(申请人提供)：抗血管生成血栓反应蛋白-1(TSP1)与CD36受体结合，触发血管内皮细胞凋亡。这通过CD95/Fas产生二次信号，CD95/Fas是一种死亡受体，通过重塑内皮独立于TSP1表达。TSP1增加CD95同源配体FasL，它与诱导剂产生的Fas结合，导致细胞凋亡。Di-TSP是一种由TSP衍生的短抑制肽，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体的水平来提高对DI-TSP的敏感性。我们将使用合成的PPARy核受体配体来调节CD36。我们将通过小剂量持续(节律)化疗改变CD95。我们建议研究：1.低剂量遗传毒物对DI-TSP比活力的影响。我们将检测DI-TSP和/或小剂量化疗对人微血管细胞(HMVECs)Fas和FasL的影响，比较DI-TSP和/或化疗对内皮细胞(EC)和癌细胞表型、Fas和FasL表达、细胞凋亡和迁移的影响。抗体、Fas诱骗受体和代谢抑制剂将被用来将CD95增加与TSP1增加的活性联系起来。2.节律化疗DI-TSP体内血管抑制作用的研究携带含有碱性成纤维细胞生长因子的Matrigel塞子的小鼠将接受DI-TSP和/或节律化疗。观察其对血管形成、Fas和FasL表达、内皮细胞L细胞凋亡程度和周细胞募集的影响。抗体、Fas诱骗受体和代谢抑制剂将被用来将CD95增加与TSP1增加的活性联系起来。3.TZDS对CD36表达及TSP1抗血管生成活性的影响用细胞凋亡、迁移抑制、增殖抑制来确定曲格列酮、罗格列酮和吡格列酮的非细胞毒性剂量，以实现CD36的最大增加。这些剂量将在体内进行Matrigel Plug试验。CD36中和抗体将用于确定其在体外和体内的贡献。4.基于TSP的联合治疗对肿瘤生长和血管生成的影响。TZDS和节律化疗将单独使用，并与DI-TSP联合使用，以阻止或延缓侵袭性PC-3或侵袭性较弱的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的抗癌药物。我们发现，联合应用抗血管生成药物和化疗可以显著减少化疗的剂量，从而减少化疗的毒性，同时显著提高抗血管生成药物的疗效。这种联合疗法为癌症和其他血管生成依赖型疾病的治疗提供了一种很有前途的新方法。