NO in Tumor Angiogenesis,Microcirculation & Rad.Therapy

NO在肿瘤血管生成、微循环中的作用

• 批准号: 7071781
• 负责人: Dai Fukumura
• 金额: $ 28.8万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7071781
• 关键词: angiogenesis; astrocytoma; blood vessels; breast neoplasms; cell cell interaction; confocal scanning microscopy; disease /disorder model; electron microscopy; enzyme inhibitors; genetically modified animals; immunocytochemistry; intravital microscopy; ionizing radiation; laboratory mouse; melanoma; microcirculation; microelectrodes; neoplasm /cancer radiation therapy; nitric oxide; nitric oxide synthase; nonhuman therapy evaluation; northern blottings; oxygen transport; vascular endothelium permeability; vascular smooth muscle; vasodilators; western blottings

In order to optimize drug and oxygen delivery to solid tumors, we plan to investigate the mechanisms, which regulate tumor angiogenesis and microcirculation. This project will focus on the role of nitric oxide (NO) in tumor angiogenesis and vessel maturation. Our goal is to improve tumor blood flow and radiation response by judicious modulation of NO levels in tumors. Control of tumor blood flow has not been achieved due to the fact that tumor vessels are functionally impaired and heterogeneous with respect to diameter, length, tortuosity, and inter-capillary distance. However, transformation to a more "normal" functional phenotype in tumor blood vessels by suppressing NO may realize this goal. Effects of NO on cell proliferation and migration are different in vascular endothelial cells (induction) and smooth muscle cells (inhibition). We hypothesize that NO induces angiogenesis in tumors (Aim 1), but inhibits vessel maturation (Aim 2), and thus, chronic NO inhibition "normalizes" tumor vessels, making them sensitive to vasodilators. NO production will be manipulated by both pharmacological and genetic approaches. Isoform-selective NO synthase (NOS) inhibitors will clarify the relative contribution of each NOS isoform. With the use of NOS deficient mice, we will examine the contribution of host stromal cells. The tumors will include glioblastoma, melanoma, and breast carcinoma grown in orthotopic sites for primary and metastatic tumors. Intravital microscopy will allow us to monitor vessel density, diameter, tortuosity, blood flow rate, vascular permeability, and response to vasoactive agents. To study endothelial-mural cell interaction in vivo, mice expressing fluorescent protein in mural cells (alphaSMA-RFP to be developed in this project) and endothelial cells (TIE2-GFP) will be visualized by multiphoton laser-scanning microscopy. Finally, improvement of tumor oxygenation and response to radiation by a vasodilator and carbogen (O2 95 percent, CO2 5 percent) breathing after chronic NO suppression will be tested (Aim 3). The insight gained in this project will have significant implications for improving tumor treatment protocols. It will suggest a novel strategy (i.e. normalization of tumor vessels) to overcome some of the physiological barriers to the delivery of therapeutic agents to solid tumors and introduce a new paradigm to study cell-cell interaction in vivo.

为了优化实体瘤的药物和氧气输送，我们计划研究调节肿瘤血管生成和微循环的机制。 该项目将重点研究一氧化氮（NO）在肿瘤血管生成和血管成熟中的作用。 我们的目标是通过明智地调节肿瘤中的一氧化氮水平来改善肿瘤血流和放射反应。 由于肿瘤血管功能受损且在直径、长度、弯曲度和毛细血管间距离方面具有异质性，因此尚未实现对肿瘤血流的控制。 然而，通过抑制NO使肿瘤血管向更“正常”的功能表型转化可能会实现这一目标。 NO 对血管内皮细胞（诱导）和平滑肌细胞（抑制）的细胞增殖和迁移的影响不同。 我们假设 NO 会诱导肿瘤中的血管生成（目标 1），但会抑制血管成熟（目标 2），因此，长期抑制 NO 可使肿瘤血管“正常化”，使它们对血管扩张剂敏感。 NO 的产生将通过药理学和遗传方法来控制。 同工型选择性 NO 合酶 (NOS) 抑制剂将阐明每种 NOS 同工型的相对贡献。 通过使用 NOS 缺陷小鼠，我们将检查宿主基质细胞的贡献。 这些肿瘤将包括在原发性和转移性肿瘤的原位部位生长的胶质母细胞瘤、黑色素瘤和乳腺癌。 活体显微镜将使我们能够监测血管密度、直径、弯曲度、血流速率、血管通透性和对血管活性药物的反应。 为了研究体内内皮-壁细胞相互作用，将通过多光子激光扫描显微镜观察在壁细胞（本项目将开发的 alphaSMA-RFP）和内皮细胞（TIE2-GFP）中表达荧光蛋白的小鼠。 最后，将测试慢性 NO 抑制后通过血管扩张剂和卡波金（O2 95%，CO2 5%）呼吸对肿瘤氧合和辐射反应的改善（目标 3）。 该项目中获得的见解将对改进肿瘤治疗方案产生重大影响。 它将提出一种新的策略（即肿瘤血管的正常化）来克服向实体瘤输送治疗剂的一些生理障碍，并引入一种新的范例来研究体内细胞与细胞的相互作用。