Investigating the role of KAT6A in MLL-rearranged acute myeloid leukemia

研究 KAT6A 在 MLL 重排急性髓系白血病中的作用

基本信息

批准号：
10686801
负责人：
Mario Andres Blanco
金额：
$ 36.55万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-09-01 至 2027-08-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10686801
关键词：
Ablation Acute Myelocytic Leukemia Binding Biochemical Biological Assay CRISPR screen Cell Cycle Cell Differentiation process Cell Proliferation Cell Survival Cells ChIP-seq Chimeric Proteins Chromatin Clinical Clustered Regularly Interspaced Short Palindromic Repeats Complex DNMT3a Data Differentiation Therapy Disease Disease Progression Disease remission ENL Protein Epigenetic Process FLT3 gene Gene Expression Genes Genetic Genetic Transcription Goals Hematologic Neoplasms Hematopoiesis Human Impairment In Vitro Individual KDM1A gene Knock-out MLL-AF9 MLL-rearranged leukemia Mass Spectrum Analysis Methodology Methods Methylcellulose Modeling Molecular Mus Myelogenous Oncogenes Patients Pharmaceutical Preparations Play Progranulocytes Proliferating Reader Role Sampling Scheme Tertiary Protein Structure Testing Therapeutic Toxic effect Work Xenograft Model acute myeloid leukemia cell burden of illness chemotherapy combinatorial design epigenome epigenomics histone acetyltransferase histone-binding proteins in vivo inhibitor mouse model mutant novel programs promoter protein complex recruit response self-renewal small molecule stemness success synergism targeted treatment therapeutic evaluation therapeutic target transcription factor transcriptome transcriptome sequencing transplant model treatment effect

项目摘要

Acute myeloid leukemia (AML) is a disease of blocked differentiation in which blasts fail to mature and proliferate continuously. Differentiation therapy, which aims to reactivate latent maturation programs and induce cell cycle exit, is curative in the promyelocytic (APL) AML subtype, but not in other AML subtypes. Epigenetic factors help sustain the differentiation block, and inhibitors of regulators such as the LSD1, BRD4, and DOT1L has recently been shown to re-activate myeloid differentiation programs in selected AML models. However, these inhibitors generally do not achieve terminal differentiation and disease remission. Accordingly, there is significant need to identify more regulators of the AML differentiation block and to test whether their inhibitors can induce terminal differentiation when used individually or in combination regiments. To identify novel regulators of AML differentiation, we recently performed a chromatin-focused CRISPR sgRNA screen using gain-of- differentiation as a readout. This screen identified the H3K9 histone acetyltransferase KAT6A as a key driver of AML differentiation arrest, and mechanistic work showed that KAT6A and the H3K9ac histone binding protein ENL closely cooperate to active promoters of AML oncogenes. We confirmed that both genetic (CRISPR) and small molecule inhibition of KAT6A markedly induces differentiation and reduces proliferation most commonly in MLL-rearranged (MLL-r) AMLs, and also in selected MLL-wild type (MLL-WT) AMLs. Further, KAT6A inhibitors synergize with inhibitors of either LSD1 or DOT1L to induce near-terminal differentiation and fully halt proliferation in vitro. This proposal has three goals: First, we will determine the mechanisms by which KAT6A and ENL are recruited to chromatin and activate transcription. We will identify the protein domains in KAT6A and the MOZ complex it resides in that are responsible for its binding to chromatin at MLL-AF9 targets and non- MLL-AF9 targets. We will also identify any transcription factors interacting with KAT6A and ENL and test their effect on recruitment of the KAT6A-ENL module to chromatin. Our second goal is to test the therapeutic potential of targeting KAT6A, individually or in combination with LSD1 or DOT1L inhibitors, in genetically-defined AML mouse models. We will employ an Mll-Af9 model and a Dnm3a/Flt3-ITD model and test the effect of inhibitor treatment schemes on disease progression and overall survival. We will also test the effect of inhibitor treatments on normal hematopoiesis. Our third goal will be to test the response of clinical AML patient samples to inhibition of KAT6A, individually or in combination with LSD1 or DOT1L inhibitors. We will perform drug response assays in MLL-r and MLL-WT samples in vitro using OP9 feeder layer culturing methodology, and will also perform PDX transplant models and test the response to KAT6A and LSD1 or DOT1L inhibitors in vivo.

急性髓样白血病（AML）是一种疾病，爆炸无法成熟并不断增殖。分化疗法，旨在重新激活潜在的成熟程序和诱导细胞周期出口，在临时细胞（APL）AML亚型中是治愈性的，但不在其他AML亚型。表观遗传因素有助于维持分化障碍，并抑制最近已证明诸如LSD1，BRD4和DOT1L之类的调节剂可以重新激活髓样选定AML模型中的分化程序。但是，这些抑制剂通常无法实现末端分化和疾病缓解。因此，有很大的需要识别更多 AML分化块的调节器，并测试其抑制剂是否可以诱导终端分化单独或组合使用时。识别AML的新型调节剂差异化，我们最近使用以染色质的CRISPR sgrna屏幕进行了区分作为读数。该屏幕将H3K9组蛋白乙酰转移酶Kat6a识别为A AML分化逮捕的主要驱动力，机械工作表明Kat6a和H3K9AC 组蛋白结合蛋白与AML癌基因的活跃启动子密切合作。我们确认遗传（CRISPR）和小分子抑制Kat6a都显着诱导分化并最常见于MLL重新培训（MLL-R）AML，并且在选定中最常见的增殖 MLL野生类型（MLL-WT）AML。此外，Kat6a抑制剂与LSD1或 dot1l在体外诱导近末端分化和完全停止增殖。该提议有三个目标：首先，我们将确定招募Kat6a和ENL的机制染色质和激活转录。我们将在Kat6a和Moz中识别蛋白质结构域复合物驻留在MLL-AF9靶标和非 - MLL-AF9目标。我们还将确定与Kat6a和ENL相互作用的任何转录因子以及测试它们对募集Kat6a-Enl模块募集到染色质的影响。我们的第二个目标是测试单独或与LSD1或DOT1L组合靶向Kat6a的治疗潜力抑制剂，在遗传定义的AML小鼠模型中。我们将采用MLL-AF9模型和 DNM3A/FLT3-ITD模型，并测试抑制剂治疗方案对疾病进展和总体生存。我们还将测试抑制剂治疗对正常造血的影响。我们的第三个目标是测试临床AML患者样品对抑制Kat6a的响应，单独或结合LSD1或DOT1L抑制剂。我们将在MLL-R进行药物反应测定，并使用OP9馈线培养方法在体外MLL-WT样品，也将执行PDX 移植模型并测试对体内Kat6a和LSD1或DOT1L抑制剂的响应。