Exploitation of Intrinsic DNA Repair Defects with DNA Damaging Agents in Cancer

项目摘要：利用DNA损伤剂开发癌症中的固有DNA修复缺陷 美国人患癌症的终身风险为1/3，癌症造成的经济负担超过1000亿 每年1美元。随着人口继续老龄化，这些数字预计将继续增加。烷基化 药物是最早用于治疗癌症的化疗药物，是应用氮芥气治疗的。 20世纪40年代耶鲁大学的淋巴瘤。在过去的80年里，许多不同类别的烷基化试剂被 它们已经发展起来，并且仍然是当今癌症治疗中不可或缺的组成部分。尽管他们有着悠久的历史和 普遍的临床应用，关于烷化剂如何损伤DNA的知识仍然知之甚少，因为 这些物种的反应性。此外，癌症通常会发展为可利用的治疗漏洞 DNA修复途径使它们能够积累更多的突变并变得更具侵略性。这 对烷化剂的不完全理解导致癌症治疗中烷化剂的经验性选择 而不是根据机制和潜在的癌症生物学进行选择。 MGMT和ALKBH2/3是两种关键的直接DNA烷基损伤逆转酶 各种烷基加合物。这些酶通常也缺乏异柠檬酸脱氢酶1/2(IDH1/2)。 突变型癌症，如胶质瘤、结直肠癌和血液系统恶性肿瘤。了解如何 烷基化子在没有任何修复酶的情况下损伤DNA，以及修复酶如何对烷基化子起作用 耐药性对于烷基化化疗的治疗进展至关重要，包括更好的 了解烷化剂、新型烷化剂的开发和个性化烷化剂的选择 根据患者肿瘤DNA修复状况。我将测试这样的假设，即靶向癌细胞在两种情况下 添加适当烷化剂的MGMT和/或ALKBH2/3将导致灵敏度增强，因为 相应的DNA修复途径会导致不可修复的损伤。 我计划通过两个目标来检验这一假设。我的第一个目标是开发一种基于LC MS的检测方法 CRISPR/Cas9诱导的胶质瘤和无细胞质粒DNA中烷基化损伤谱的研究 模特们。这一目标将回答烷化剂如何通过鉴定物种和 无细胞质粒DNA和各种胶质瘤模型细胞系形成的大量DNA烷基化加合物 使用一组临床使用的烷化剂进行治疗。我的第二个目标是进行高吞吐量 基于DNA修复途径状态的烷化剂敏感性差异筛选。这一目的将阐明 已知的DNA修复途径与烷化剂敏感性的关系。最终，这项工作可能会对 关于烷基化化疗的治疗进展，包括开发新型烷化剂和 基于患者肿瘤DNA修复状态的个性化烷化剂选择。

Project Summary: Exploitation of Intrinsic DNA Repair Defects with DNA Damaging Agents in Cancer The lifetime risk of cancer in the U.S. is 1 in 3 and the financial burden of cancer exceeds 100 billion dollars annually. These figures are predicted to continue increasing as populations continue to age. Alkylating agents were the first chemotherapies used to treat cancer with the application of nitrogen mustard gas to treat lymphoma in the 1940s at Yale. Over the last 80 years, many different classes of alkylating agents have been developed and they remain an integral component of cancer treatment today. Despite their long history and prevalent clinical usage, knowledge of how alkylating agents damage DNA is still poorly understood due to the reactive nature of these species. Additionally, cancers often develop exploitable therapeutic vulnerabilities in DNA repair pathways that enable them to accumulate more mutations and become more aggressive. This incomplete understanding of alkylators results in the empirical selection of alkylating agents in cancer treatment regimens rather than selection based on mechanism and underlying cancer biology. MGMT and ALKBH2/3 are two key direct DNA alkyl damage reversal enzymes responsible for repairing a variety of alkyl adducts. These enzymes are also commonly deficient in isocitrate dehydrogenase1/2 (IDH1/2) mutant cancers such as gliomas, colorectal cancers, and hematological malignancies. Understanding how alkylators damage DNA in the absence of any repair enzymes and how repair enzymes contribute to alkylator resistance is crucial for the therapeutic advancement of alkylating chemotherapies including a better understanding of alkylating agents, the development of novel alkylators, and personalized alkylator selection based on patient tumor DNA repair status. I will test the hypothesis that targeting cancer cells deficient in either MGMT and/or ALKBH2/3 with the appropriate alkylator will result in enhanced sensitivity because deficiency in the corresponding DNA repair pathway will lead to unrepairable damage. I plan to test this hypothesis through two aims. My first aim is to develop a LCMS-based assay to profile the spectrum of alkylation damage in cell free plasmid DNA and CRISPR/Cas9 generated glioma models. This aim will answer the question of how alkylators damage DNA by identifying both the species and quantities of DNA alkylation adducts that form when cell free plasmid DNA and various glioma model cell lines are treated with a panel of clinically used alkylators. My second aim is to conduct a high-throughput differential screen for alkylator sensitivity based on DNA repair pathway status. This aim will elucidate the relationship between known DNA repair pathways and alkylator sensitivity. Ultimately, this work could contribute to the therapeutic advancement of alkylating chemotherapies including the development of novel alkylators and personalized alkylator selection based on patient tumor DNA repair status.