HISTOCHEMICAL MARKER OF TUMOR HYPOXIA

肿瘤缺氧的组织化学标志物

• 批准号: 2094051
• 负责人: JAMES ARTHUR RALEIGH
• 金额: $ 16.8万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-02-01 至 1997-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2094051
• 关键词: acidity /alkalinity; adduct; biomarker; chemical binding; chemical kinetics; chemical synthesis; colorimetry; cytotoxicity; enzyme linked immunosorbent assay; flow cytometry; hypoxia; imidazole; immunocytochemistry; immunofluorescence technique; laboratory rabbit; monoclonal antibody; neoplasm /cancer chemotherapy; neoplasm /cancer radiation therapy; radiation sensitivity; stainings; tissue /cell culture

Tumor hypoxia can compromise the effectiveness of radiation treatment and chemotherapy by proliferation dependent cytotoxins. On the other hand, hypoxic tumor cells are potential targets for selective chemotherapy by hypoxic cell cytotoxins. Rational intervention directed at hypoxic tumor cells by hyperbaric oxygen, carbogen breathing, hypoxic cell radiosensitizers, perfluorohydrocarbon emulsions or hypoxic cell cytotoxins will require a convenient way of measuring changes in hypoxia in individual tumors in particular patients. This revised competing continuation grant application proposes that the hypoxic cell marker, Pimonidazole, can serve the purpose of measuring tumor hypoxia in a clinical setting. The hypoxia cell marker approach depends on the fact that, at low oxygen concentrations (<10 mm Hg partial pressure), cellular redox enzymes efficiently activate nitroaromatic compounds in a way which leads to their irreversible binding to cellular macromolecules. The tissue bound nitroaromatic compounds become markers of tumor hypoxia with a resolution on the scale of single cells. When suitably labeled, the markers can be detected by autoradiography, scintillation counting, single photon emission tomography, positron emission transaxial tomography, magnetic resonance spectroscopy or immunochemistry methods. In the immunochemistry method, which is the focus of this grant application, hypoxic cells can be detected by means of fluorescent or colorimetric immunostaining of tumor sections (microscopy), enzyme linked immunosorbent assay (enzyme digested tissue biopsy) or flow cytometry (disaggregated tissue biopsy). The six Specific Aims of the grant application are designed to broaden the scientific basis of the hypoxia marker approach. Specifically, the synthesis of large quantities of Pimonidazole will be carried out as well as the syntheses of smaller amounts of other markers for mechanistic studies. The chemical nature of hypoxia marker binding to hypoxic cells will be investigated. The effect of intracellular pH on subcellular localization of Pimonidazole will be studied. The rate of catabolism of Pimonidazole adducts in hypoxic cells will be followed and compared with the rates of catabolism for other hypoxia markers. A full characterization of the oxygen dependence of Pimonidazole binding to hypoxic cells will be made. Monoclonal antibody reagents to Misonidazole will be prepared to complement those already available for Pimonidazole.

肿瘤缺氧会损害放射治疗的有效性， 用增殖依赖性细胞毒素进行化疗。另一方面， 低氧肿瘤细胞是选择性化疗的潜在靶点 低氧细胞毒素。针对缺氧性肿瘤的理性干预 高压氧、二氧化碳呼吸、低氧细胞 放射增敏剂、全氟碳氢化合物乳剂或缺氧细胞 细胞毒素需要一种方便的方法来测量缺氧时的变化 在个别肿瘤中，特别是在患者身上。本修订后的竞争对手 继续批准申请提出缺氧细胞标志物， 匹莫硝唑，可以用于测量肿瘤缺氧的目的 临床环境。 缺氧细胞标记物的方法依赖于这样一个事实，即在低氧条件下 浓度(&lt；10毫米汞柱分压)、细胞氧化还原酶 有效地激活硝基芳香族化合物，从而导致它们 与细胞大分子的不可逆结合。用纸巾装订的 硝基芳香族化合物成为肿瘤缺氧的标志 在单个细胞的规模上。当适当标记时，标记物可以 通过放射自显影、闪烁计数、单光子检测 发射断层扫描，正电子发射跨轴断层扫描，磁性 共振光谱学或免疫化学方法。在免疫化学中 方法，这是此授予申请的重点，低氧细胞可以 通过肿瘤的荧光或比色免疫染色检测的 切片(显微镜)、酶联免疫吸附试验(酶消化 组织活检)或流式细胞术(分解组织活检)。 拨款申请的六个具体目标旨在扩大 低氧标记法的科学基础。具体地说， 此外，还将进行大量匹莫硝唑的合成。 作为机械的少量其他标记的合成 学习。低氧标记与低氧细胞结合的化学性质 将会被调查。胞内pH对亚细胞的影响 将对匹莫硝唑进行本地化研究。其分解代谢率 低氧细胞中的匹莫硝唑加合物将被跟踪并与 其他低氧标志物的分解代谢率。一个完整的 吡芒硝唑结合的氧依赖性的表征 就会产生低氧细胞。抗咪唑的单抗试剂 将准备对已有的匹莫硝唑进行补充。