FOLATE POLYGLUTAMATION/TRANSPORT IN CANCER THERAPEUTICS

癌症治疗中的叶酸多谷氨酸/转运

• 批准号: 2748755
• 负责人: ANDRE ROSOWSKY
• 金额: $ 21.31万
• 依托单位: DANA-FARBER CANCER INST
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-01 至 2000-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2748755
• 关键词: X ray crystallography; active sites; antineoplastics; binding proteins; chemical kinetics; chemical synthesis; enzyme inhibitors; enzyme structure; folate antagonist; glutamate ammonia ligase; intermolecular interaction; isozymes; membrane transport proteins; ornithine; polyglutamates; tetrahydrofolates; tetrahydrofolylpolyglutamate synthase; tissue /cell culture; vitamin analog; vitamin metabolism

DESCRIPTION: (Applicant's Abstract) The overall goal of this project is the synthesis of novel substrates and inhibitors of folylpolyglutamate synthetase (FPGS) with a view to defining the structural requirements for tight binding to the active site and gaining a better understanding of the molecular mechanism of action of this physiologically important enzyme. In addition, these studies will yield new information about the optimal structural features for cellular uptake of folate analogs via the reduced folate carrier (RFC) and membrane folate-binding protein (mFBP) transport pathways. It is hoped that knowledge gained through these studies will contribute to possible development of inhibitors of folate polyglutamylation and/or uptake as a discrete class of antifolates for cancer therapeutics. Specific types of compounds to be synthesized will include: (1) intermediate product and transition state analogs of the FPGS reaction; (2) folate and tetrahydrofolate analogs that retain the glutamic acid moiety but are modified in the `bay region' comprised by the B-ring, bridge, aryl, and CONH moieties; (3) analogs in which the gamma-CO2H group is replaced by NO2, SO2H, and PO2H2 groups; (4) analogs with gamma,gamma-difluoroornithine side chains; and (5) GSH-activated and other prodrug derivatives of the best available ornithine-type analogs. The kinetics of interaction of these compounds with FPGS will be determined as part of an established collaboration with Dr. R.G. Moran (Medical College of Virginia, Richmond), whereas their membrane transport characteristics in different cells will be determined in collaboration with Dr. G. Jansen (Free University Hospital, Amsterdam). In addition, where such studies are indicated, compounds will be co-crystallized with FPGS and the crystals analyzed by X-ray crystallography to obtain critical information about how FPGS inhibitors bind to the active site. The crystallographic studies will be part of an ongoing collaboration with Dr. V. Cody (Hauptman-Wood Medical Research Institute, Buffalo). It is hoped that these interactive studies may ultimately lead to development of a therapeutic agent based on the exploitation of qualitative or quantitative differences in binding specificity which are thought to exist between/among FPGS isoforms in tumor and nontumor tissues, and which may also be present, in principle, at the level of membrane transport. In addition to the binding and uptake assays, the new compounds derived from this project will be tested for the ability to inhibit growth of cultured tumor cells, with the hope of identifying one or more promising candidates for scaled up synthesis and further preclinical development.

描述：（申请人的摘要）该项目的总体目标是 叶酰聚谷氨酸新型底物和抑制剂的合成 合成酶（FPGS），以确定其结构要求 与活性位点紧密结合并更好地了解 这种生理上重要的酶的分子作用机制。 在 此外，这些研究将产生关于最佳方案的新信息 通过减少细胞摄取叶酸类似物的结构特征 叶酸载体 (RFC) 和膜叶酸结合蛋白 (mFBP) 运输 途径。 希望通过这些研究获得的知识能够 有助于叶酸聚谷氨酰化抑制剂的可能开发 和/或作为一类独立的抗叶酸剂用于癌症治疗。 待合成的具体化合物类型包括：(1) FPGS反应的中间产物和过渡态类似物； (2) 叶酸和四氢叶酸类似物保留了谷氨酸部分，但 在由 B 环、桥、芳基和组成的“湾区”中进行修饰 CONH部分； (3) γ-CO2H基团被NO2取代的类似物， SO2H和PO2H2基团； (4) γ,γ-二氟鸟氨酸侧类似物 链条； (5) GSH激活和其他最佳前药衍生物 可用的鸟氨酸型类似物。 这些相互作用的动力学 带有 FPGS 的化合物将被确定为已建立的 与 R.G. 博士的合作莫兰（弗吉尼亚医学院，里士满）， 而它们在不同细胞中的膜运输特性将是 与 G. Jansen 博士（自由大学医院， 阿姆斯特丹）。 此外，如果有此类研究表明，化合物将 与 FPGS 共结晶并通过 X 射线分析晶体 晶体学以获得有关 FPGS 抑制剂如何发挥作用的关键信息 结合到活性位点。 晶体学研究将成为 与 V. Cody 博士（Hauptman-Wood 医学研究中心）持续合作 研究所，布法罗）。 希望这些互动研究能够 最终导致基于以下的治疗剂的开发 利用结合中的定性或定量差异 被认为存在于肿瘤中 FPGS 亚型之间的特异性 和非肿瘤组织，原则上也可能存在于 膜运输水平。 除了结合和摄取测定之外， 来自该项目的新化合物将进行能力测试 抑制培养的肿瘤细胞的生长，希望能够识别出一种 或更有希望用于扩大合成和进一步临床前的候选药物 发展。