Investigating novel synthetic lethal epigenetic interactions in Acute Myeloid Leukemia

项目总结/摘要 急性髓性白血病（AML）是一种造血系统恶性肿瘤，其特征在于异常的自我更新， 阻止骨髓祖细胞的分化。AML的许多致癌驱动因素都集中在 表观遗传和转录调节途径的失调，产生对 这些监管者。在AML中已经确定了少数表观遗传依赖性，然而，单药治疗 针对表观遗传调节因子的抑制剂在AML患者中显示出有限的治疗功效。到 为了改善我们对AML中表观遗传学相关协同遗传相互作用的有限理解，我们开发了 一种高效的基于CRISPR-Cas 12 a的方法，使我们能够进行双缺失遗传筛选。 我们的初步研究确定并验证了两对新的相互作用的合成病态组合， AML中的表观遗传调节因子：含溴结构域蛋白9（BRD 9）和含Jumonji结构域蛋白 蛋白6（JMJD 6）以及赖氨酸乙酰转移酶6（KAT 6）和JMJD 6。JMJD 6是一款双功能 精氨酸脱甲基酶和赖氨酰羟化酶调节转录增强子的激活， 这两个协同对的表观遗传因子缺失。BRD 9是染色质重塑SWI/SNF的组分 复杂，以前被确定为AML特异性依赖。KAT 6A是一种组蛋白乙酰转移酶 和转录辅激活因子。我们假设BRD 9/JMJD 6和KAT 6A/JMJD 6协同作用 在转录和染色质水平上。在两种相互作用中JMJD 6的存在表明JMJD 6- 缺陷建立了一个独特的转录和染色质状态，使AML细胞对不同的表观遗传敏感， 压力在目的1中，我们将研究BRD 9/JMJD 6和KAT 6A/JMJD 6在细胞中的合成病态相互作用。 在体外和体内以及目标2中，我们将剖析BRD 9/JMJD 6的AML特异性合成病态相互作用， KAT 6A/JMJD 6在分子水平上。我们提出的研究将提供基本的机械洞察力， 新的AML合成病态表观遗传相互作用维持AML发病机制。成功完成 拟议的研究对开发创新的表观遗传途径具有重要的前景 治疗和揭示AML发病机制的基本生物学见解。 1

Project Summary/Abstract Acute myeloid leukemia (AML) is a hematopoietic malignancy characterized by aberrant self-renewal and blocked differentiation of myeloid progenitor cells. Many of the oncogenic drivers of AML converge in dysregulation of epigenetic and transcriptional regulation pathways, generating de novo dependencies on these regulators. A handful of epigenetic dependencies have been identified in AML, however, single-agent inhibitors against epigenetic regulators have shown limited therapeutic efficacy in patients with AML. To improve our limited understanding of epigenetic-related synergistic genetic interactions in AML, we developed a highly efficient CRISPR-Cas12a-based method enabling us to perform double deletion genetic screening. Our preliminary studies identified and validated two pairs of novel interacting synthetic sick combinations of epigenetic regulators in AML: bromodomain containing protein 9 (BRD9) and Jumonji domain-containing protein 6 (JMJD6) as well as the lysine acetyltransferase 6 (KAT6) and JMJD6. JMJD6 is a bi-functional arginine demethylase and lysyl-hydroxylase regulating transcription enhancer activation and was identified in both synergistic pairs of epigenetic factor deletions. BRD9 is a component of chromatin remodeling SWI/SNF complex and was previously identified as an AML specific dependency. KAT6A is a histone acetyltransferase and transcriptional co-activator. We hypothesize that BRD9/JMJD6 and KAT6A/JMJD6 interact synergistically at the level of transcription and chromatin. The presence of JMJD6 in both interactions suggests that JMJD6- deficiency sets up a unique transcription and chromatin state that sensitizes AML cells to distinct epigenetic stresses. In Aim 1, we will investigate the synthetic sick interactions of BRD9/JMJD6 and KAT6A/JMJD6 in vitro and in vivo and in Aim 2, we will dissect the AML-specific synthetic sick interactions of BRD9/JMJD6 and KAT6A/JMJD6 at the molecular level. Our proposed studies will offer basic mechanistic insight into how these novel AML synthetic sick epigenetic interactions sustain AML pathogenesis. Successful completion of the proposed studies holds significant promise towards developing innovative epigenetic pathway-directed therapies and revealing fundamental biological insights into the pathogenesis of AML. 1