DNA Methyltransferase Inhibition by Intercalating Agents

嵌入剂对 DNA 甲基转移酶的抑制

• 批准号: 7633273
• 负责人: Keith D Robertson
• 金额: $ 18.98万
• 依托单位: AUGUSTA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7633273
• 关键词: Accounting; Address; Adriamycin PFS; Adverse effects; Affect; Antineoplastic Agents; Apoptosis; Cancer Patient; Cause of Death; Cell Cycle Arrest; Cell physiology; Cells; Chemotherapy-Oncologic Procedure; Chromatin; Chromatin Structure; Colonic Neoplasms; DMA-methyltransferase; DNA; DNA Binding; DNA Methylation; DNA Methylation Inhibition; DNA Methyltransferase; DNA Modification Methylases; DNA biosynthesis; DNA methyltransferase inhibition; Development; Doxorubicin; Effectiveness; Epigenetic Process; Genes; Genetic Transcription; Genome; Genome Stability; Genomics; Goals; Growth; Health; Human; In Vitro; Induction of Apoptosis; Inhibition of Apoptosis; Intercalating Agents; Knowledge; Lead; Life; Link; Malignant Neoplasms; Measures; Mediating; Methylation; Modification; Molecular; Molecular Mechanisms of Action; Pattern; Pharmaceutical Preparations; Phenotype; Process; Property; Proteins; Recombinant DNA; Regulator Genes; System; Testing; Topoisomerase II; Tumor Cell Line; Tumor Suppressor Genes; United States; Work; cancer cell; cancer therapy; cell growth; chemotherapy; cytotoxicity; design; genome-wide; improved; in vitro Assay; in vivo; inhibitor/antagonist; killings; neoplastic cell; prevent; promoter; success; tumor

DESCRIPTION (provided by applicant): Anti-cancer drugs of the DNA intercalator class, which includes doxorubicin (adriamycin), are among the most effective and widely used agents in systemic cancer chemotherapy. Numerous mechanisms have been proposed to be responsible for intercalator-mediated cytotoxicity, including inhibition of DNA topoisomerase II and DNA replication, yet none of these can completely account for the myriad effects these agents have seen shown to exert on cells. Our incomplete understanding of the molecular mechanism of action of DNA intercalators prevents them from being used as effectively as possible. Epigenetic genome modifications, in particular DNA methylation, have now been recognized as major regulators of gene activity and genomic stability. Indeed, the DNA methylation machinery and cellular DNA methylation patterns are disrupted in nearly all tumor cells. Emerging evidence indicates that chemotherapeutic drugs can alter DNA methylation patterns. How anti-cancer drugs such as DNA intercalators alter the efficacy of the DNA methylation machinery - and vice versa - has been largely unexplored. The central hypothesis we plan to test in this application is that inhibition of DNA methyltransferases (DNMTs) by DNA intercalating agents leads to alterations in genomic DNA methylation patterns and contributes directly to intercalator-mediated cell growth inhibition and apoptosis of human cancer cells. The three aims of this proposal are designed to test this hypothesis. In aim 1, the inhibition properties of a group of DNA intercalating agents on the major DNMTs will be characterized in vitro using both DNA and chromatin substrates. Our second aim entails characterizing the effects of DNA intercalating agents on both DNA methylation patterns (global and gene-specific) and the DNMTs in vivo in tumor cell lines. Lastly, we aim to determine whether cellular DNA methyltransferase levels influence the capacity of DNA intercalating drugs to induce cell cycle arrest and apoptosis in human tumor cell lines. Addressing these questions will advance our understanding of how DNA intercalating agents exert their powerful anticancer effects and how their inhibition of DNA methylation affects this process. This is expected to positively affect human health by allowing for the development of new therapies that maximize the anti-tumor properties of DNA intercalating agents and minimize their side-effects. Cancer is one of the leading causes of death in the United States and chemotherapy is frequently employed to treat cancer patients, however the success rate is variable and our current repertoire of drugs is limited. It is therefore critical to understand how these drugs function to kill tumor cells and determine how they can be used more effectively. Elucidating the molecular mechanism of a widely utilized class of anticancer drugs known as DNA intercalators is the focus of this proposal.

描述（由申请人提供）：包括阿霉素（阿霉素）在内的DNA介导剂类的抗癌药物是全身性癌症化学疗法中最有效且最广泛使用的药物之一。已经提出了许多机制来负责嵌入剂介导的细胞毒性，包括抑制DNA拓扑异构酶II和DNA复制，但这些都无法完全解释这些药物所发现的这些药物对细胞的施加的众多影响。我们对DNA介导剂作用的分子机理的不完全理解使它们无法尽可能有效地使用它们。现已被认为是基因活性和基因组稳定性的主要调节剂，表观遗传基因组修饰，特别是DNA甲基化。实际上，在几乎所有肿瘤细胞中，DNA甲基化机制和细胞DNA甲基化模式都被破坏。新兴的证据表明，化学治疗药物可以改变DNA甲基化模式。抗癌药（例如DNA介导剂）如何改变DNA甲基化机制的功效，反之亦然。我们计划在此应用中检验的中心假设是，通过DNA互化剂对DNA甲基转移酶（DNMT）的抑制会导致基因组DNA甲基化模式的改变，并直接促进嵌入剂介导的细胞生长抑制人类癌细胞。该提案的三个目标旨在检验该假设。在AIM 1中，使用DNA和染色质底物在体外表征了一组DNA插入剂对主要DNMT的抑制特性。我们的第二个目标需要表征DNA互插剂对肿瘤细胞系中体内DNA甲基化模式（全球和基因特异性）和DNMT的影响。最后，我们旨在确定细胞DNA甲基转移酶水平是否影响DNA插入药物诱导人肿瘤细胞系中细胞周期停滞和凋亡的能力。解决这些问题将促进我们对DNA插入剂如何发挥其强大的抗癌作用以及其对DNA甲基化的抑制作用的理解。预计这将通过允许开发新的疗法来对人类健康产生积极影响，从而最大程度地提高DNA插入剂的抗肿瘤特性并最大程度地减少其副作用。癌症是美国死亡的主要原因之一，经常采用化学疗法来治疗癌症患者，但是成功率是可变的，我们目前的药物库有限。因此，了解这些药物如何杀死肿瘤细胞并确定如何更有效地使用它们是至关重要的。该提案的重点是阐明广泛使用的抗癌药物的分子机制。