Investigating the Role of DNMT3A mutations in the initiation and maintenance of myeloid malignancies

研究 DNMT3A 突变在骨髓恶性肿瘤发生和维持中的作用

• 批准号: 10321210
• 负责人: Michael R Waarts
• 金额: $ 3.56万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-04 至 2022-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10321210
• 关键词: AML/MDS; Acute Myelocytic Leukemia; Binding Sites; CRISPR screen; CRISPR/Cas technology; Catalytic Domain; Cells; Clonal Expansion; DNA Binding; DNMT3a; DNMT3a mutation; Dependence; Development; Disease; Dysmyelopoietic Syndromes; Epigenetic Process; Epitopes; Event; FLT3 gene; Gene Frequency; Genes; Genetic; Genetic Heterogeneity; Genomics; Head; Hematopoiesis; Human; Individual; Knowledge; Laboratories; Leukemic Cell; Maintenance; Malignant - descriptor; Malignant Neoplasms; Medicine; Memorial Sloan-Kettering Cancer Center; Mentorship; Modeling; Molecular; Mutation; Myeloproliferative disease; NPM1 gene; Oncogenic; Oncology; Pathogenesis; Patients; Phenotype; Play; Precancerous Conditions; Prognosis; Proteins; Research Institute; Resources; Role; Schools; Suggestion; Tertiary Protein Structure; Therapeutic; Treatment Failure; Work; anticancer research; career development; chemotherapy; epigenome; fitness; gain of function; genetic variant; mouse model; mutant; novel; novel therapeutic intervention; premalignant; prevent; programs; recombinase; research and development; restoration; self-renewal; stem cells; therapeutic target; therapy development; treatment strategy; tumor

PROJECT SUMMARY/ABSTRACT Acute myeloid leukemia (AML) is an aggressive malignancy with a poor prognosis, owing in part to substantial intratumor genetic heterogeneity that allows specific subclones to evade even intensive chemotherapy. Genomic studies have identified the spectrum of frequent mutations in AML and suggest a model of sequential mutational acquisition. Early mutations are believed to confer a fitness advantage to a stem or progenitor cell enabling clonal expansion and later mutations within this expanding subclone may confer a proliferative advantage resulting in overt malignancy. AML can occur de novo, but may also develop in patients with myelodysplastic syndrome (MDS) or clonal hematopoiesis (CH). Across these disease states, DNMT3A mutations are critical initiating mutations, suggesting an opportunity to target the founding clone of these malignancies. However, targeting of DNMT3A mutations remains elusive due to a poor understanding of the mechanisms and specific role(s) of these mutations in disease. The objective of this proposal is to elucidate the specific oncogenic mechanisms of two frequent DNMT3A mutations and to define their functional contributions in the maintenance of CH, MDS, and AML. We hypothesize that genetic restoration of wildtype DNMT3A will block progression of DNMT3A-mutant CH/MDS/AML and thus that targeting the initiating DNMT3A mutations can provide a therapeutic option in myeloid disease. Moreover, a complete understanding of DNMT3A mutations will allow for the identification of targetable vulnerabilities conferred by these mutations. Specific Aim 1 will utilize inducible mouse models and ex vivo CRISPR screens to define the phenotypes, mechanisms, and conferred vulnerabilities of two DNMT3A mutations in distinct functional domains of the protein. Specific Aim 2 will use dual recombinase murine models capable of turning on and off DNMT3A mutations to determine the reversibility of DNMT3A-mutant CH and to evaluate the oncogenic dependency of DNMT3A mutations in MDS/AML. The implications of these studies will lead to novel therapeutic approaches for DNMT3A-mutant malignancies. This proposal will be conducted in the laboratory of Dr. Ross Levine (the Sponsor), who is the head of the Molecular Cancer Medicine program. The Levine lab is part of the Human Oncology and Pathogenesis Program at Memorial Sloan Kettering Cancer Center (MSK), a state of the art cancer research institute. Mentorship will also be provided by Dr. Kristian Helin (the Co-Sponsor), who is the head of the Center for Epigenetics at MSK. These affiliations, along with the strong scientific and non-scientific assets of the Gerstner Sloan Kettering Graduate School, will provide a rich set of collaborative, technical, and scientific resources to execute the proposed research and career development.

项目总结/摘要 急性髓性白血病（AML）是一种侵袭性恶性肿瘤，预后不良，部分原因是大量的骨髓细胞浸润。 肿瘤内的遗传异质性，使特定的亚克隆逃避甚至密集的化疗。基因组 研究已经确定了AML中常见的突变谱，并提出了一种连续突变模型， 采集早期突变被认为赋予干细胞或祖细胞适应性优势，从而使克隆形成成为可能。 扩增和随后在该扩增亚克隆内的突变可赋予增殖优势， 明显的恶性肿瘤AML可以从头发生，但也可能在骨髓增生异常综合征患者中发生 (MDS)或克隆造血（CH）。在这些疾病状态中，DNMT 3A突变是关键的启动因子。 突变，这表明有机会靶向这些恶性肿瘤的创始克隆。然而，针对 DNMT 3A突变仍然是难以捉摸的，这是由于对这些突变的机制和具体作用的理解不足。 疾病中的突变 本提案的目的是阐明两种常见的DNMT 3A的特定致癌机制， 突变，并确定其在CH、MDS和AML的维持中的功能贡献。我们假设 野生型DNMT 3A的遗传恢复将阻断DNMT 3A突变型CH/MDS/AML的进展， 靶向起始DNMT 3A突变可以为骨髓疾病提供治疗选择。而且 对DNMT 3A突变的全面了解将有助于识别有针对性的漏洞 由这些突变引起的。Specific Aim 1将利用诱导型小鼠模型和离体CRISPR筛选 定义两种DNMT 3A突变的表型、机制和赋予的脆弱性， 蛋白质的功能结构域。Specific Aim 2将使用能够开启 和关闭DNMT 3A突变，以确定DNMT 3A突变CH的可逆性，并评估致癌性。 MDS/AML中DNMT 3A突变的依赖性。这些研究的意义将导致新的治疗方法 DNMT 3A突变型恶性肿瘤的方法。 本提案将在Ross Levine博士（申办者）的实验室进行，他是 分子癌症医学计划。莱文实验室是人类肿瘤学和发病机制计划的一部分 在纪念斯隆凯特琳癌症中心（MSK），一个最先进的癌症研究机构。导师制将 也由克里斯蒂安·赫林博士（共同赞助商）提供，他是MSK表观遗传学中心的负责人。 这些隶属关系，沿着强大的科学和非科学资产的郭士纳斯隆凯特林 研究生院，将提供一套丰富的协作，技术和科学资源，以执行 建议研究和职业发展。