ACIDIFICATION OF HUMAN MELANOMA XENOGRAFTS

人类黑色素瘤异种移植物的酸化

• 批准号: 6663969
• 负责人: DENNIS B. LEEPER
• 金额: $ 22.84万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-02-01 至 2003-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6663969
• 关键词: SCID mouse; acidity /alkalinity; cellular pathology; cellular respiration; enzyme activity; extracellular; glucose metabolism; glucose transport; glycolysis; hexokinase; human tissue; hyperglycemia; hyperthermia; intracellular; lactates; melanoma; membrane transport proteins; mitochondria; neoplastic cell; neoplastic growth; nuclear magnetic resonance spectroscopy; tissue /cell culture

Hyperglycemia reduces the pHe of transplantable rodent tumors by 0.1 - 0.4 pH unit. Human tumors are acidified by an average of 0.17 pH unit. Extracellular acidification of 0.2 unit is unlikely to sensitize human tumors to hyperthermia since the average pHe is 7.15. The goal of this research is to significantly acidify tumors for the purpose of hyperthermia. The hypothesis to be tested is that hyperglycemia-induced acidification of human melanoma xenografts can be increased by inhibition of mitochondrial respiration or by inhibition of membrane proton pumps to enhance the therapeutic gain. Inhibition of respiration will shift glucose metabolism toward glycolysis and the production of lactic acid, and inhibition of the membrane proton pumping. Inhibition of respiration will shift glucose metabolism toward glycolysis and the production of lactic art, and inhibition of the membrane protein pumping mechanism will allow the inflow of extracellular hydrogen ions. In these studies respiration will be inhibited during hyperglycemia with meta-iodobenzylguanide (MIBG), and membrane proton pumps will be inhibited during hyperglycemia by Cariporide mesilate (Hoechst HOE642 to inhibit the Na+/H+ exchanger, NHE1) and DIDS (to inhibit the Cl-HCO3-exchanger). The hypothesis will be tested in F2 human melanoma xenografts. By using both invasive and non-invasive MRS techniques we will determine: 1. Therapeutic gain by tumor growth delay compared to bone marrow proliferative potential (CFU-GM); 2. Tumor versus normal tissue (brain muscle) intracellular and extracellular acidification; 3. Tumor and normal tissue lactic acid levels; 4. Tumor and normal tissue blood flow; 5. Relationship of tumor vasculature distribution and glucose distribution; 6. Tumor pO2 distribution and 7. Tumor Glut-1, hexokinase activity and rate of respiration. Hyperglycemia will be induced by oral or i.v. glucose administration to SCID mice bearing 8-10 mm diameter melanomas selected from our melanoma frozen tumor bank on the basic of metabolic parameters. MIBG or HOE642 and/or DIDS will be administered i.p. at the time of peak blood glucose concentration followed by hyperthermia (1 hour at 42 degrees Celsius by leg immersion). MRS will be performed by Dr. Jerry Glickson, University of Pennsylvania. Explanted tumor cells will be provided to Projects 1, 2 & 3. The kinetics of adaptation of melanoma cells to growth at low pHe and the effect of hyperthermia response will be determined in culture. The in vitro characterization of the human melanomas will provide critical information for Projects 1, 2 & 3 and will provide a cellular basis for the hyperthermia response of xenografts. Furthermore, in vivo results will validate findings from Projects 1, 2, & 3. These results will provide the preclinical data required for the design and implementation of a phase I/II clinical trial to acutely acidify human tumors in association with therapy.

高血糖使可移植啮齿动物肿瘤的 pHe 降低 0.1 - 0.4 pH 单位。人类肿瘤平均酸化 0.17 pH 单位。 0.2单位的细胞外酸化不太可能使人类过敏 由于平均 pHe 为 7.15，因此肿瘤容易出现高温。此举的目标 研究目的是显着酸化肿瘤 高热。要检验的假设是高血糖引起的 通过抑制可以增加人黑色素瘤异种移植物的酸化 线粒体呼吸或通过抑制膜质子泵 增强治疗增益。抑制呼吸会改变葡萄糖 糖酵解和乳酸产生的代谢，以及 抑制膜质子泵送。呼吸会受到抑制 将葡萄糖代谢转向糖酵解和乳酸的产生 艺术，并且抑制膜蛋白泵送机制将允许 细胞外氢离子的流入。在这些研究中呼吸 在高血糖期间会被间碘苄胍 ​​(MIBG) 抑制， 在高血糖期间，膜质子泵将受到抑制 卡立波利甲磺酸盐（Hoechst HOE642 抑制 Na+/H+ 交换器 NHE1） 和 DIDS（抑制 Cl-HCO3 交换剂）。假设将被检验 在 F2 人类黑色素瘤异种移植物中。通过使用侵入性和非侵入性 我们将通过 MRS 技术确定： 1. 肿瘤生长带来的治疗效果 与骨髓增殖潜力（CFU-GM）相比延迟； 2. 肿瘤 与正常组织（脑肌肉）细胞内和细胞外相比 酸化; 3.肿瘤和正常组织乳酸水平； 4.肿瘤和 正常组织血流量； 5. 肿瘤脉管系统的关系 分布和葡萄糖分布； 6. 肿瘤 pO2 分布和 7. 肿瘤 Glut-1、己糖激酶活性和呼吸速率。高血糖 将通过口服或静脉注射诱导。 SCID 小鼠葡萄糖注射 直径为 8-10 毫米的黑色素瘤选自我们的黑色素瘤冷冻肿瘤 以代谢参数为基础。 MIBG 或 HOE642 和/或 DIDS 将 腹膜内给药血糖浓度达到峰值时 然后进行热疗（腿部浸泡 42 摄氏度 1 小时）。 MRS 将由宾夕法尼亚大学的 Jerry Glickson 博士进行。 外植的肿瘤细胞将提供给项目 1、2 和 3。 黑色素瘤细胞对低 pHe 条件下生长的适应及其影响 高热反应将在培养中确定。体外 人类黑色素瘤的表征将提供关键信息 为项目 1、2 和 3 提供细胞基础 异种移植物的高热反应。此外，体内结果将 验证项目 1、2 和 3 的结果。这些结果将提供 设计和实施一个阶段所需的临床前数据 急性酸化人类肿瘤的 I/II 临床试验 治疗。