ALKYLTRANSFERASE INHIBITORS FOR CANCER CHEMOTHERAPY

用于癌症化疗的烷基转移酶抑制剂

• 批准号: 6266799
• 负责人: ANTHONY E PEGG
• 金额: $ 23.97万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-08-01 至 2006-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6266799
• 关键词: active sites; alkyltransferase; antineoplastics; carmustine; cell line; enzyme activity; enzyme inhibitors; guanine analog; mutant; neoplasm /cancer pharmacology; oligonucleotides

DESCRIPTION: Clinical trials with O6-benzylguanine (b6G) are in progress. The success of this therapy may be compromised by: (a) the facile production of mutants of hAGT resistant to b6G; (b) the lack of adequate potency and tumor specificity and (c) the enhanced toxicity of alkylating agent therapy when AGT inhibitors are used. Experiments are proposed to address these issues building on advances made during the previous period of support which include: (i) development of a selection method for b6G-resistant mutants; (ii) studies showing that these mutants can protect mammalian cells from alkylating agents in the presence of b6G, (iii) derivation of the crystal structure of the hAGT protein; and (iv) indications that short oligodeoxynucleotides containing b6G are extremely potent inactivators of hAGT. The proposed research project has three specific aims. The first specific aim is to characterize the interaction between hAGT and b6G and oligos containing b6G. Studies in this aim will test and refine the current models for binding of b6G and related compounds to hAGT by comparing the inactivation by (and binding of) various b6G derivatives to hAGT mutant proteins in which residues thought to be involved in binding are altered. It is also planned to use various mutants of hAGT such as C145S and inhibitors to obtain crystal structures of complexes with hAGT showing how binding occurs. The second specific aim will obtain a full understanding of hAGT mutants with altered sensitivity to b6G and other inhibitors. Many point mutations (and at least one naturally occurring polymorphic variant) in hAGT render the protein resistant to inactivation by b6G. Such mutant forms of hAGT may create problems in the therapeutic use of b6G but also provide an opportunity to protect normal cells such as bone marrow by gene therapy approaches in which a mutant form is expressed. These studies will provide a detailed knowledge of the sites in hAGT protein at which resistant mutants can occur, and will study the stability and activity of these mutants when expressed in cells. Furthermore, the studies in this specific aim are aimed at isolating mutants more sensitive to inactivation by b6G. Finally, studies in Specific Aim 3 will study the inactivation of hAGT and sensitization of cells to alkylating agents brought about by novel agents inactivating hAGT. Studies will be carried out to develop second generation agents and will develop leads obtained in the current grant support period which include: short oligos containing b6G, pro-drugs generating b6G, and better knowledge of the binding pocket into which the target base is flipped by the hAGT.

描述：正在进行O6-苯二唑烷（B6G）的临床试验。这 这种疗法的成功可能会受到以下方式的损害：（a） 抗B6g的hagt的突变体； （b）缺乏足够的效力和肿瘤 特异性和（c）AGT时烷基化剂疗法的毒性增强 使用抑制剂。提出了实验来解决这些问题建设 在上一期支持期间取得的进步，其中包括：（i） 开发用于B6G耐药突变体的选择方法； （ii）研究 表明这些突变体可以保护哺乳动物细胞免受烷基化剂 在B6G存在的情况下，（iii）哈格晶体结构的推导 蛋白质; （iv）迹象表明含有B6G的短寡脱氧核苷酸 是哈格的极有效的灭活因子。 拟议的研究项目具有三个具体目标。第一个特定目标 是为了表征hagt和b6g和含有寡寡的相互作用 B6G。此目的的研究将测试和完善当前的结合模型 B6G及其相关化合物与HAGT通过比较（结合 of）对HAGT突变蛋白的各种B6G衍生物，残留物思考 参与结合的参与会改变。还计划使用各种 HAGT的突变体，例如C145S和抑制剂，以获得的晶体结构 HAGT的复合物显示结合的发生方式。第二个特定目标将 完全了解对B6G敏感性改变的HAGT突变体 其他抑制剂。许多点突变（至少一个天然发生 hagt中的多态性变体）使蛋白质抗灭活能力。 B6G。这种突变形式的hagt可能会在治疗的使用中造成问题 B6G，但也提供了保护正常细胞（例如骨髓）的机会 通过表达突变形式的基因治疗方法。这些研究 将提供有关hagt蛋白中的地点的详细知识 可以发生抗性突变体，并将研究这些突变体的稳定性和活性 突变体在细胞中表达。此外，在这个特定目标中的研究 旨在隔离对B6G灭活更敏感的突变体。最后， 特定目标3中的研究将研究哈格的失活和敏化 新型药物灭活HAGT带来的烷基化剂的细胞。 将进行研究以发展第二代药物，并将 在当前赠款支持期间获得的发展潜在客户，其中包括：简短 含有B6G的寡核酸，生成B6G的Pro-Clugs以及对 绑定的袋子被hagt翻转到目标基础上。