INTERACTIONS OF ANTITUMOR AGENTS WITH NUCLEIC ACIDS

抗肿瘤剂与核酸的相互作用

• 批准号: 2090462
• 负责人: David E Graves
• 金额: $ 9.23万
• 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/2090462
• 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.

该项目将探索与相关的生物物理特性 所选抗肿瘤药物的相互作用（及其结构 相关类似物）与核酸。 在此期间 研究，努力将集中于将物理- 这些药物-DNA 相互作用的化学性质及其生物学特性 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/或化学的问题 决定拓扑异构酶 II 抑制的特性，无论这些特性 特性与这些化合物的 DNA 结合有关，并且 最后，它们引发拓扑异构酶 II 的机制 抑制。 所提出的几种主要抗肿瘤药物的机制 药物，包括 m-AMSA、VP-16、VM-26、阿霉素、柔红霉素和 米托蒽醌介导的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 药物发挥这种抑制作用的方式是有限的。 然而，这些化合物与 DNA 相互作用的能力并不 似乎是抑制的必要条件 拓扑异构酶 II 发生。 我们设计、合成并 表征了一系列经过修饰的苯胺吖啶化合物 连接至 N-苯基侧链和吖啶环以用作 用于检查药物所需的结构要求的探针 诱导拓扑异构酶 II 抑制发生。 本系列吖啶 类似物为检查和表征提供了独特的机会 与三元络合物相关的物理化学性质 形成并评估化学取代基类型和的影响 介导拓扑异构酶 II 活性的位置。 的活动 这些化合物被认为以三元络合物的形式存在 拓扑异构酶 II-DNA 和药物之间。我们将探讨结构性 和这种三元复合物的功能特性，使用各种 方法包括将抗肿瘤剂光亲和交联 DNA（和/或拓扑异构酶 II）。 3-叠氮基-m-AMSA 将提供 用于检查拓扑异构酶-DNA-药物三元复合物的理想探针 并深入了解 m-AMSA 发挥其作用的机制 生物效应。 在光解之前，该化合物已被 被证明以与母体 m-AMSA 相同的方式结合 DNA。 光解后，叠氮基转化为反应性氮宾， 原位形成共价连接。 我们实验室最近 观察到 3-叠氮基-m-AMSA 的非共价加成正如 有效引发拓扑异构酶 II 抑制作为母体 m- AMSA；表明其作为检查的探针的有效性 m-AMSA 的机械特性。 通过这个探测器，我们将尝试 深入了解三元复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 拓扑异构酶 II 抑制存在和不存在时的相互作用 抗生素。 这些对几种选定的抗肿瘤药物（类似物）的研究将 帮助我们深入了解这些化合物如何 发挥其有效的生物效应和药物DNA的性质 复合物，从而导致新型抗肿瘤药物的设计更加合理 代理。