DNMT3A in Development of Hematologic Malignancies

DNMT3A 在血液系统恶性肿瘤发展中的作用

基本信息

批准号：
10689132
负责人：
MARGARET A. GOODELL
金额：
$ 52.26万
依托单位：
BAYLOR COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-09-11 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10689132
关键词：
Acute Lymphocytic Leukemia Acute Myelocytic Leukemia Alleles Cell Line Cells Clustered Regularly Interspaced Short Palindromic Repeats Collaborations DNA Methylation DNA Modification Methylases DNMT3a Dependence Development Disease Epigenetic Process Event FLT3 gene Funding Gene Expression Genes Genetic Transcription Goals Hematologic Neoplasms Hematopoiesis Hematopoietic System Hematopoietic stem cells Homeobox Genes Human Human Cell Line Lymphoid Malignant Neoplasms Methylation Modeling Molecular Mus Mutate Mutation Myelogenous NPM1 gene Nuclear Phase Premalignant Cell Process Progress Reports Sampling Shapes Site Tumor Suppressor Proteins Umbilical Cord Blood Work acute myeloid leukemia cell cell type dosage epigenome epigenomics human DNA improved insight leukemia leukemia/lymphoma mouse model mutant novel therapeutic intervention premalignant progenitor protein expression self-renewal stem stem cells stem-like cell tumor

项目摘要

Abstract DNA METHYLTRANSFERASE 3A (DNMT3A) has emerged over the past ~8 years as one of the most important tumor suppressors in the hematopoietic system, being mutated across most types of human hematologic malignancies, and found in greater than 20% of acute myeloid leukemias (AMLs) as well as acute lymphoid leukemias (ALLs) and lymphomas. Through mechanisms that are not understood, DNMT3A mutations are thought to provide a fertile ground for secondary mutations which drive the frank malignancy. In the previous funding period, we sought to establish and study a reliable tumor model of DNMT3A-associated malignancies using the recognized collaboration between DNMT3A-mutation and the internal tandem duplication (ITD) of FLT3 which results in highly penetrant malignancies of both myeloid and lymphoid types. Here, we will study the very earliest events that represent the transition from clonal hematopoiesis to malignacy. We hypothesize that DNMT3A mutations and NPM1 mutations collaborate effectively by enforcing complementary epigenetic changes that serve to maintain mutated cells in an HSC-like state. We expect that a key effect of this dysregulation is aberrant expression of HOX genes that drives self- renewal. We will dissect the mechanisms through which this occurs here using mouse models, human cell lines, and human primary samples. Our long-term goal is to use insights developed here to enforce differentiation and develop new therapeutic strategies. We will (1) Identify the epigenetic and molecular changes associated with the development of malignancies from Dnmt3a-deficient hematopoietic progenitors. Using mice that have mutant alleles of Dnmt3a-KO and inducible NPM1c, we will examine the concerted changes that occur at the epigenetic and transcriptional levels in pre-malignant stem and progenitor cells. (2) Examine the dependencies of AML with mutated DNMT3A, NPM1, and FLT3-ITD. We hypothesize this common sub-type of AML is dependent on the sustained expression of particular genes such as Hox and Meis1. We will examine this and other potential dependencies using CRISPR KO or targeted DNA methylation. (3) Examine in human DNMT3A-mutated AML cells epigenome remodeling and dependencies. We will validate targets identified in Aims 1 and 2, and explore the value of specific modulators such as nuclear re- localization of NPM1, correction of the DNMT3A-mutant allele, and re-methylation of specific target sites. These studies will reveal the stepwise epigenomic changes that occur due to loss of DNMT3A that lead to AML as well as some of their dependencies. This will lead to an improved understanding of how loss of DNMT3A promotes malignancies, and potentially to new therapeutic strategies due to identification of new targets.

抽象的 DNA 甲基转移酶 3A (DNMT3A) 在过去约 8 年中出现，成为一种造血系统中最重要的肿瘤抑制因子，大多数类型都发生突变人类血液系统恶性肿瘤中，超过 20% 的急性髓系白血病中发现（AML）以及急性淋巴细胞白血病（ALL）和淋巴瘤。通过机制尚不清楚，DNMT3A 突变被认为为继发性提供了肥沃的土壤导致明显恶性肿瘤的突变。在上一个资助期间，我们试图建立并利用公认的方法研究 DNMT3A 相关恶性肿瘤的可靠肿瘤模型 DNMT3A 突变与 FLT3 内部串联重复 (ITD) 之间的协作导致骨髓和淋巴类型的高度渗透性恶性肿瘤。在这里，我们将学习代表从克隆造血向恶性肿瘤转变的最早事件。我们假设 DNMT3A 突变和 NPM1 突变通过强制执行有效协作互补的表观遗传变化有助于将突变细胞维持在 HSC 样状态。我们预计这种失调的一个关键影响是 HOX 基因的异常表达，从而驱动自我更新。我们将使用小鼠模型剖析发生这种情况的机制，人类细胞系和人类初级样本。我们的长期目标是利用所开发的见解在这里加强差异化并开发新的治疗策略。我们将 (1) 确定与恶性肿瘤发展相关的表观遗传和分子变化 Dnmt3a 缺陷的造血祖细胞。使用具有 Dnmt3a-KO 突变等位基因的小鼠和诱导型 NPM1c，我们将检查表观遗传和癌前干细胞和祖细胞的转录水平。 (2)检查依赖关系 DNMT3A、NPM1 和 FLT3-ITD 突变的 AML。我们假设这个常见的子类型 AML 依赖于 Hox 和 Meis1 等特定基因的持续表达。我们将使用 CRISPR KO 或靶向 DNA 检查此依赖性和其他潜在依赖性甲基化。 (3) 检查人 DNMT3A 突变的 AML 细胞表观基因组重塑和依赖关系。我们将验证目标 1 和 2 中确定的目标，并探索具体目标的价值调节剂，例如 NPM1 的核重新定位、DNMT3A 突变等位基因的校正，和特定靶位点的重新甲基化。这些研究将揭示逐步的表观基因组由于 DNMT3A 丢失而发生的变化导致 AML 及其某些依赖关系。这将有助于更好地理解 DNMT3A 丢失如何促进恶性肿瘤，并可能由于新靶标的确定而产生新的治疗策略。

项目成果

期刊论文数量（7）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

First-in-Class Allosteric Inhibitors of DNMT3A Disrupt Protein-Protein Interactions and Induce Acute Myeloid Leukemia Cell Differentiation.

DOI：
10.1021/acs.jmedchem.2c00725
发表时间：
2022-07-22
期刊：
Journal of medicinal chemistry
影响因子：
7.3
作者：
Jonathan E. S;oval;oval;R. Ramabadran;Nathaniel J. Stillson;Letitia Sarah;D. Fujimori;M. Goodell;N. Reich
通讯作者：
N. Reich

New insights into the biology of acute myeloid leukemia with mutated NPM1.

对 NPM1 突变的急性髓系白血病生物学的新见解。