INTERACTIONS OF ANTITUMOR AGENTS WITH NUCLEIC ACIDS

抗肿瘤剂与核酸的相互作用

• 批准号: 3181994
• 负责人: David E Graves
• 金额: $ 9.31万
• 依托单位: UNIVERSITY OF MISSISSIPPI
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-03-01 至 1996-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3181994
• 关键词: DNA; DNA topoisomerases; adduct; affinity labeling; aminoacridines; analog; antineoplastics; biophysics; chemical binding; chemical kinetics; chemical models; chemical structure function; chemical substitution; conformation; drug interactions; enzyme complex; enzyme inhibitors; fluorescence spectrometry; hydrogen bond; methane sulfonate; nuclear magnetic resonance spectroscopy; nucleic acid sequence; nucleic acid structure; pharmacokinetics; photolysis; synthetic nucleic acid; thermodynamics

This project will explore the biophysical properties associated with the interactions of selected antitumor agents (and their structurally relevant analogs) with nucleic acids. During the course of this research, efforts will be focused towards correlating the physical- chemical nature of these drug-DNA interactions with their biological effectiveness as topoisomerase II inhibitors. Experiments will be designed to address questions concerning the physical and/or chemical properties which dictate topoisomerase II inhibition, whether these properties are related to the DNA binding of these compounds, and finally, the mechanism(s) by which they elicit topoisomerase II inhibition. The proposed mechanism by which several of the leading antitumor agents, including m-AMSA, VP-16, VM-26, adriamycin, daunorubicin, and mitoxantrone mediate antitumor activity is through the inhibition of topoisomerase II activity. Information concerning the actual mechanism by which the drugs exert this type of inhibition effect is limited. However, the ability for these compounds to interact with DNA does appear to be an essential requirement for inhibition of the topoisomerase II to occur. We have designed, synthesized, and characterized a series of anilinoacridine compounds with modifications to both the N-phenyl side chain and to the acridine ring to use as probes for examining the structural requirements necessary for drug- induced topoisomerase II inhibition to occur. This series of acridine analogs provide a unique opportunity for examining and characterizing both the physical-chemical properties associated with ternary complex formation and evaluating the influence of chemical substituent type and position on mediating topoisomerase II activity. The activities of these compounds is presumed to reside in formation of a ternary complex between the topoisomerase II-DNA and drug. We will probe the structural and functional properties of this ternary complex, using a variety of methods including photoaffinity crosslinking of the antitumor agent to the DNA (and/or topoisomerase II). The 3-azido-m-AMSA will provide an ideal probe for examining the topoisomerase-DNA-drug ternary complex and provide insight into the mechanism(s) by which m-AMSA exerts its biological effects. Prior to photolysis, this compound has been demonstrated to bind DNA in a manner identical to the parent m-AMSA. Upon photolysis, the azido is converted to the reactive nitrene which forms a covalent attachment in situ. Our laboratory has recently observed that the noncovalent addition of 3-azido-m-AMSA was just as effective in eliciting topoisomerase II inhibition as the parent m- AMSA; indicative of its effectiveness as a probe for examining the mechanistic properties of m-AMSA. With this probe, we will attempt to obtain insight into the overall geometry of the ternary complex (i.e., the location of drug with respect to topoisomerase II and DNA). In addition, our studies will examine the binding properties and topological specificities associated with topoisomerase II-DNA interactions in the absence and presence of topoisomerase II inhibiting antibiotics. These studies on several selected antitumor agents (analogs) will provide insight into our overall understanding of how these compounds exert their potent biological effects and the nature of the drug-DNA complexes, thus leading to a more rational design of novel antitumor agents.

该项目将探讨与 选定的抗肿瘤剂的相互作用（及其结构上 与核酸相关的类似物。 在此过程中 研究，努力将集中于与身体的联系 - 这些药物-DNA相互作用与其生物学的化学性质 作为拓扑异构酶II抑制剂的有效性。 实验将是 旨在解决有关物理和/或化学物质的问题 决定拓扑异构酶II抑制的特性，是否这些 属性与这些化合物的DNA结合有关，并且 最后，它们引起拓扑异构酶II的机制 抑制。 几种领先的抗肿瘤的提议机制 特工，包括M-AMSA，VP-16，VM-26，Adrimycin，Daunorubicin和 Mitoxantrone介导抗肿瘤活性是通过抑制 拓扑异构酶II活性。 有关实际机制的信息 药物施加这种抑制作用受到限制。 但是，这些化合物与DNA相互作用的能力确实 似乎是抑制的必不可少的要求 拓扑异构酶II发生。 我们已经设计，合成，并且 表征了一系列具有修饰的苯二酰酸化合物 到N-苯基侧链和尖锐的环 检查药物所需的结构要求的探针 - 诱导的拓扑异构酶II抑制发生。 这一系列ac 类似物为检查和表征提供了独特的机会 与三元复合物相关的物理化学特性 形成和评估化学取代基类型的影响和 介导拓扑异构酶II活性的位置。 活动 这些化合物被认为是在形成三元络合物中的 在拓扑异构酶II-DNA和药物之间。我们将探测结构 和该三元复合物的功能特性，使用多种 包括抗肿瘤剂的光性交联的方法 DNA（和/或拓扑异构酶II）。 3-齐多-M-Amsa将提供 检查拓扑异构酶-DNA-DRUG三元络合物的理想探针 并提供有关MAMSA发挥其机制的见解 生物学效应。 在光解之前，该化合物已经 证明是以与母体M-AMSA相同的方式结合DNA。 光解时，叠氮化物被转化为反应性硝酸盐 原位形成共价附件。 我们的实验室最近有 观察到3-齐多-M-Amsa的非共价添加同样 有效地引发拓扑异构酶II作为母体m- amsa;指示其有效性作为研究 M-AMSA的机械性能。 通过此调查，我们将尝试 了解三元络合物的整体几何形状（即 药物相对于拓扑异构酶II和DNA的位置。 在 此外，我们的研究将检查结合特性和 与拓扑异构酶II-DNA相关的拓扑特异性 在不存在和存在拓扑异构酶II的情况下相互作用 抗生素。 这些对几种选定抗肿瘤剂（类似物）的研究将 洞悉我们对这些化合物的整体理解 发挥其有效的生物学作用和药物-DNA的性质 复合物，从而导致更合理的新型抗肿瘤设计 代理商。