Design of Programmable Genotoxins

可编程基因毒素的设计

• 批准号: 6616458
• 负责人: JOHN M ESSIGMANN
• 金额: $ 38.31万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-16 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6616458
• 关键词: DNA damage; DNA repair; adduct; androgen receptor; aniline; apoptosis; breast neoplasms; cell line; chemical structure function; chemical synthesis; disease /disorder model; drug design /synthesis /production; estrogen receptors; intermolecular interaction; laboratory mouse; mustard compounds; mutagens; progesterone receptors; prostate neoplasms; xenotransplantation

DESCRIPTION (provided by applicant): The hypothesis was put forth recently that the ability of a widely used drug to eradicate a specific diseased cell population could be attributed in part to the ability of that drug to form a special type of DNA adduct. The adduct attracted proteins selectively expressed in the diseased cell. It was reasoned that adducts engaged in tight complexes with proteins would be difficult to repair. The concealed adducts would persist in and selectively kill the diseased cells. The adduct-shielding model suggested a new paradigm by which aberrantly expressed proteins might be exploited to increase the specificity of genotoxic compounds. Bifunctional molecules were designed in which a DNA damaging warhead was tethered to a recognition domain for the estrogen receptor (ER), which is over expressed in many tumors. DNA adducts were formed that were strongly attracted to the ER in vitro and selectively killed cells that over expressed the ER. DNA damaging molecules were also designed that successfully attracted the androgen receptor (AR) and progesterone receptor (PR) to DNA adducts, and these molecules also caused selective cell killing. In the only case thus far examined, one compound was also shown to kill tumors in mouse xenografts. The goal of the proposed work is to elucidate the mechanism by which selective killing occurs. Our hypothesis is that the ER, AR and PR bind to the toxin-DNA adducts and preclude access to the adducts by repair enzymes. In proposed studies, the removal of DNA lesions engaged in complexes with the steroid receptors will be assessed; these studies will determine whether the receptors can indeed hinder repair of the DNA lesions. Synthetic methods will be applied to vary the architecture and properties of the novel DNA adduct complexes in order to identify the molecular features responsible for selective toxicity. Incorporation of protein recognition domains with a range of affinities for hormone receptors will establish whether DNA adducts engaged in tighter adduct-binding complexes are more difficult to repair (and hence more toxic) than those in weaker complexes. Variation of the warhead will be used to direct damage to different helical surfaces. Alterations in the linker connecting the warhead and protein recognition domain will establish the optimal molecular arrangements for adduct-receptor interactions, repair shielding and selective toxicity.

描述（由申请人提供）：最近提出的假设是，一种广泛使用的药物根除特定患病细胞群的能力可能部分归因于该药物形成特殊类型的 DNA 加合物的能力。加合物吸引了在患病细胞中选择性表达的蛋白质。据推测，与蛋白质形成紧密复合物的加合物难以修复。隐藏的加合物会持续存在并选择性地杀死患病细胞。加合物屏蔽模型提出了一种新的范例，通过该范例可以利用异常表达的蛋白质来提高基因毒性化合物的特异性。双功能分子的设计中，DNA损伤弹头与雌激素受体（ER）的识别域相连，雌激素受体（ER）在许多肿瘤中过度表达。形成的 DNA 加合物在体外被 ER 强烈吸引，并选择性杀死过度表达 ER 的细胞。还设计了DNA损伤分子，成功地将雄激素受体（AR）和孕激素受体（PR）吸引到DNA加合物上，这些分子还引起选择性细胞杀伤。在迄今为止检查的唯一案例中，一种化合物也被证明可以杀死小鼠异种移植物中的肿瘤。拟议工作的目标是阐明选择性杀伤发生的机制。我们的假设是 ER、AR 和 PR 与毒素-DNA 加合物结合并阻止修复酶接触加合物。在拟议的研究中，将评估与类固醇受体复合物中 DNA 损伤的去除；这些研究将确定受体是否确实能够阻碍 DNA 损伤的修复。合成方法将用于改变新型 DNA 加合物复合物的结构和特性，以确定导致选择性毒性的分子特征。与激素受体具有一系列亲和力的蛋白质识别域的结合将确定参与更紧密的加合物结合复合物的DNA加合物是否比那些较弱的复合物更难以修复（因此毒性更大）。弹头的变化将用于直接损坏不同的螺旋面。连接弹头和蛋白质识别域的连接体的改变将为加合物-受体相互作用、修复屏蔽和选择性毒性建立最佳分子排列。