Novel Topoisomerase I Inhibitors

新型拓扑异构酶 I 抑制剂

基本信息

批准号：
7985671
负责人：
MARK S CUSHMAN
金额：
$ 39.22万
依托单位：
PURDUE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2001
资助国家：
美国
起止时间：
2001-09-10 至 2015-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7985671
关键词：
Address African Animal Model Antibiotics Antineoplastic Agents Biochemical Biochemistry Biological Biological Assay Camptothecin Cell Culture Techniques Cell Line Charge Chemotherapy-Oncologic Procedure Clinical Clinical Research Clinical Trials Collaborations Complex Computer Graphics Crystallography DNA Drug Design Drug Kinetics Drug toxicity Electrostatics Enzyme Inhibitor Drugs Enzyme Inhibitors Evaluation Fiber Foundations Future Goals Homing Human Hybrids Hydrogen Bonding Hydrolysis Implant Inhibition of Cell Proliferation Kinetics Ligands Link London Mammalian Cell Mediating Methods Modification Molecular Molecular Models Molecular Weight Monitor National Cancer Institute Nitrogen Normal Cell Pharmaceutical Chemistry Phosphodiesterase I Proteins Quantum Mechanics Reaction Relative (related person)Relaxation Research Resistance Solid Neoplasm Structure Superhelical DNA Testing Topoisomerase-I Inhibitor Toxic effect Trypanosoma Type I DNA Topoisomerases Xenograft procedure absorption analog base cancer cell cancer therapy charge transfer complex cytotoxicity design inhibitor/antagonist inorganic phosphate intercalation link protein molecular mechanics molecular modeling novel phosphodiester public health relevance research clinical testing tumor tumor growth tyrosyl-DNA phosphodiesterase uptake van der Waals force

项目摘要

DESCRIPTION (provided by applicant): The long-term goals of this project are to design, synthesize and evaluate novel topoisomerase I (Top1) inhibitors for the treatment of cancer. The clinical studies will allow future problems revealed by the clinical results to be addressed immediately and effectively. This could include structural modification to address potential problems resulting from drug toxicity, resistance, unfavorable pharmacokinetics, and lack of potency. The Top1 design strategy will involve an evaluation of the fundamental forces stabilizing the inhibitor/enzyme/DNA ternary complexes through medicinal chemistry, computer graphics molecular modeling, molecular mechanics, ab initio quantum mechanics, and biochemical studies. In addition, the design of new Top1 inhibitors will be aided by crystallography inhibitor/enzyme/DNA of ternary complexes, which will facilitate structure-based drug design. A variety of synthetic methods will be employed in the syntheses of new Top I inhibitors, including indenoisoquinoline-camptothecin hybrids termed "aromathecins", nitrogen analogues of the aromathecins, and azaindenoisoquinolines. The resulting anticancer agents will be targeted to cancer cells and solid tumors through attachment of low molecular weight homing ligands that will be removed metabolically after selective uptake into cancer cells as opposed to normal cells. The conjugates will be evaluated by testing the release mechanism, monitoring inhibition of cell proliferation, blocking the attachment of the homing ligand to cancer cells to help elucidate mechanism of action, and determining selectivities in the NCI panel of cancer cell cultures. The phosphodiester bond linking Tyr723 of Top I to the 3'-phosphate of DNA in stalled cleavage complexes is hydrolyzed by tyrosyl-DNA-phosphodiesterase I (Tdp1). Since Tdp1 inhibitors counteract the action of Top1 inhibitors, Tdp1 inhibitors might interact synergistically with Top1 inhibitors. A goal of this project is to incorporate both Top1 and Tdp1 inhibitory activities into the same anticancer agents, which are expected be significantly more potent than those of Top I inhibitors lacking Tdp1 inhibitory activity. This will exploit a unique discovery of Tdp1 inhibitory activity in several indenoisoquinolines. The Top1 inhibitors resulting from this study will be evaluated in a variety of assays including those involving: 1) Top1-mediated DNA cleavage reactions; 2) Top1-DNA linkage and reversibility of cleavage complexes; 3) kinetics of cleavage complex formation and reversal; 4) DNA unwinding to monitor intercalation; 5) inhibition of Top1-mediated DNA relaxation; 6) protein-linked strand breaks induced by inhibitors in mammalian cells; 7) cytotoxicity assays in cancer cell cultures, including camptothecin-resistant cells lines; 8) hollow fiber studies and xenograft testing; 9) antibiotic activity vs. African trypanosomes. PUBLIC HEALTH RELEVANCE: This is a competitive renewal application for the design and synthesis of topoisomerase I inhibitors for the treatment of cancer in humans. The project has already generated two clinical candidates, indimitecan and indotecan, which will undergo clinical evaluation at the National Cancer Institute. The continuation of the project will allow the medicinal chemistry, crystallography, and biochemistry components of the project to remain actively involved so that the potential limitations of the two clinical candidates can be addressed effectively.

描述（由申请人提供）：该项目的长期目标是设计，合成和评估新型的拓扑异构酶I（TOP1）抑制剂以治疗癌症。临床研究将使未来的问题通过临床结果揭示，可以立即有效地解决。这可能包括结构性修饰，以解决因药物毒性，耐药性，不利的药代动力学和缺乏效力而引起的潜在问题。 TOP1设计策略将涉及通过药物化学，计算机图形分子建模，分子力学，量级量子力学和生化研究稳定抑制剂/酶/DNA三元络合物的基本力的评估。此外，新型TOP1抑制剂的设计将通过三元络合物的晶体学抑制剂/酶/DNA的帮助，这将促进基于结构的药物设计。在新的顶部I抑制剂的合成中将采用多种合成方法，包括称为“芳香蛋白”，芳族芳族蛋白的氮类似物的indenoisoquinoline-Camptothecin杂种，以及Azaindenoisoquinolines。所得的抗癌剂将通过附着低分子量的归巢配体来靶向癌细胞和实体瘤，这些配体在选择性摄取对癌细胞而与正常细胞相反，该配体将被代谢去除。结合物将通过测试释放机制，监测细胞增殖的抑制，阻止托架配体的附着在癌细胞上，以帮助阐明作用机理，并确定癌细胞培养物NCI的选择性。在停滞的裂解络合物中，将顶部I的Tyr723与DNA的3'-磷酸连接的磷酸二酯键被酪糖基-DNA-磷酸二酯酶I（TDP1）水解。由于TDP1抑制剂抵消了TOP1抑制剂的作用，因此TDP1抑制剂可能与TOP1抑制剂协同相互作用。该项目的一个目的是将TOP1和TDP1抑制活性同时纳入相同的抗癌剂，预计这比缺乏TDP1抑制活性的TOP I抑制剂的有效性明显更高。这将利用几种indenoisoquinolines中TDP1抑制活性的独特发现。该研究产生的TOP1抑制剂将在包括涉及的各种测定中进行评估：1）TOP1介导的DNA裂解反应； 2）裂解复合物的Top1-DNA连接和可逆性； 3）切割复合物形成和逆转的动力学； 4）DNA放弃监测插入； 5）抑制TOP1介导的DNA松弛； 6）由哺乳动物细胞抑制剂诱导的蛋白连接链断裂； 7）在癌细胞培养物中的细胞毒性测定，包括抗甲虫的耐药细胞系； 8）空心纤维研究和异种移植测试； 9）抗生素活性与非洲锥虫。公共卫生相关性：这是对拓扑异构酶I抑制剂的设计和合成以治疗人类癌症的竞争性更新应用。该项目已经产生了两个临床候选者，即Indimitecan和Indotecan，该候选者将在国家癌症研究所接受临床评估。该项目的延续将允许该项目的药物化学，晶体学和生物化学组成部分积极参与，以便可以有效地解决这两个临床候选者的潜在局限性。