Targeting an RNA Binding Protein Network in Acute Myeloid Leukemia

靶向急性髓系白血病中的 RNA 结合蛋白网络

• 批准号: 10408047
• 负责人: Omar Abdel-Wahab
• 金额: $ 54.47万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10408047
• 关键词: Ablation; Acute Myelocytic Leukemia; Adaptor Signaling Protein; Address; Adult; Binding; Biological; CD34 gene; CRISPR/Cas technology; Cancer cell line; Cell Line; Cell physiology; Cells; Clinical; Clustered Regularly Interspaced Short Palindromic Repeats; Complex; Data; Dependence; Disease; Drug Targeting; Evaluation; Excision; Exons; Genetic; Genetic Engineering; Genetic Models; Genetic Transcription; Growth; HOXA9 gene; Hematopoiesis; Hematopoietic; Hematopoietic stem cells; Histologic; Human; Impairment; In Vitro; Introns; Link; Liquid substance; Maintenance; Malignant - descriptor; Malignant Neoplasms; Mediating; Messenger RNA; Methods; Modeling; Mutation; Non-Malignant; Nucleosomes; Oncogenic; Patients; Pharmaceutical Preparations; Pharmacology; Physiological; Play; Population; Protein Splicing; Proteins; Proteomics; RNA; RNA Binding; RNA Recognition Motif; RNA Splicing; RNA analysis; RNA-Binding Proteins; Recurrence; Role; Sampling; Solid; Sulfonamides; Time; Tissues; Transcription Elongation; Translations; Up-Regulation; acute myeloid leukemia cell; anti-cancer; base; cancer cell; cancer survival; cell type; conditional knockout; improved; in vivo; insight; leukemia; leukemia initiating cell; loss of function; member; mouse model; mutant; novel; novel strategies; overexpression; patient derived xenograft model; progenitor; stem; treatment strategy; tumorigenesis; ubiquitin ligase

RNA-binding proteins (RBPs) are essential modulators of transcription and translation frequently dysregulated in cancer. We recently systematically interrogated RBP dependencies in a number of human cancers using a comprehensive CRISPR/Cas9 domain-focused screen targeting RNA-binding domains (RBDs) of 490 classical RBPs. This uncovered a network of physically interacting RBPs upregulated in acute myeloid leukemia (AML) and crucial for maintaining physiological RNA splicing and AML survival. Genetic targeting of one key member of this network, RBM39, repressed cassette exon inclusion and promoted intron retention within mRNAs encoding HOXA9 targets as well as in other RBPs preferentially required in AML. Fortuitously, it has recently been described that a class of clinically validated anti-cancer sulfonamide compounds (including the drugs indisulam and E7820) mediate RBM39 degradation as their dominant cellular mechanism of action. This occurs via novel interactions between these compounds and the DCAF15 adapter protein of the CUL4/Ddb1 ubiquitin ligase complex with RBM39 as a neo-substrate. Treatment of AML cells with such compounds in vitro and in vivo resulted in similar lethal cellular effects due to perturbations in RNA splicing. The effects of RBM39 loss on splicing resulted in preferential lethality of spliceosomal mutant AML, providing a novel strategy for treatment of AML bearing recurrent mutations in RBPs that regulated splicing. Overall these data identify RBM39 as central to a network of functionally and physically interacting RBPs upregulated in AML over normal hematopoietic precursors and required for AML maintenance. Despite these insights we do not yet understand the basis for the cell- and context-specific roles of RBM39 in malignant versus normal hematopoietic cells. We also do not understand the exact mechanisms by which RBM39 loss results in eradication of AML. We hypothesize that RBM39 is differentially required in malignant versus normal hematopoietic cells, may be differentially required depending on the precise stage of hematopoiesis, and will be required for leukemia initiation as well as maintenance. These hypotheses will be addressed in two Specific Aims. Aim 1 will determine the biological role of RBM39 in normal and malignant hematopoiesis. In this Aim, we will utilize a novel genetic model for genetic deletion of RBM39 in vivo in a cell- and time-specific manner to rigorously dissect the roles of RBM39 in malignant versus normal hematopoietic stem and progenitor cell populations. Aim 2 will identify the mechanistic basis for cell-type and disease-specific roles for RBM39 in normal and malignant hematopoietic cells. In this Aim we will compare the direct RNA binding targets and effects of RBM39 loss on splicing across normal and malignant hematopoietic cells. In addition, we will evaluate a potential novel for RBM39 in transcriptional elongation by the FACT complex, identified by our preliminary studies as an interactor of RBM39.

RNA结合蛋白（RBP）是转录和翻译的重要调节因子，经常发生失调 在癌症中。最近，我们系统地询问了RBP的依赖性，在一些人类癌症中使用的是一种 全面的CRISPR/Cas9结构域聚焦筛选，靶向490个经典的RNA结合结构域（RBD） 限制性商业惯例。这揭示了在急性髓细胞白血病（AML）中上调的物理相互作用RBPs网络 并且对于维持生理RNA剪接和AML存活至关重要。一个关键成员的基因靶向 在这个网络中，RBM 39抑制了盒外显子的包含，并促进了mRNA中内含子的保留 编码HOXA 9靶标以及AML中优先需要的其他RBP中。幸运的是，它最近 已经描述了一类临床验证的抗癌磺酰胺化合物（包括药物 indisulam和E7820）介导RBM 39降解作为其主要细胞作用机制。这 通过这些化合物与CUL 4/Ddb 1的DCAF 15衔接蛋白之间的新型相互作用发生 泛素连接酶复合物与RBM 39作为新底物。用这样的化合物治疗AML细胞 由于RNA剪接的扰动，体外和体内导致相似的致死细胞效应。的影响 RBM 39剪接缺失导致剪接体突变AML优先致死，提供了一种新的策略 用于治疗在调节剪接的RBP中携带复发性突变的AML。 总体而言，这些数据将RBM 39确定为功能和物理相互作用RBPs网络的中心 在AML中相对于正常造血前体上调，并且是AML维持所需的。尽管有这些 我们还不了解RBM 39在恶性肿瘤中的细胞和环境特异性作用的基础。 与正常造血细胞相比。我们也不了解RBM 39丢失的确切机制， 导致AML的根除。我们假设RBM 39在恶性肿瘤和恶性肿瘤中的需求不同， 正常的造血细胞，可能是不同的需要，这取决于确切的阶段， 造血，并将需要白血病的启动以及维持。这些假设 将在两个具体目标中加以解决。目的1将确定RBM 39在正常和高血压中的生物学作用。 恶性造血在这个目标中，我们将利用一种新的遗传模型，在基因缺失RBM 39， 以细胞和时间特异性的方式在体内严格剖析RBM 39在恶性肿瘤与正常肿瘤中的作用。 造血干细胞和祖细胞群。目标2将确定细胞类型的机制基础， RBM 39在正常和恶性造血细胞中的疾病特异性作用。在这个目标中，我们将比较 直接RNA结合靶点和RBM 39缺失对正常和恶性造血细胞剪接的影响 细胞此外，我们将通过FACT评估RBM 39在转录延伸中的潜在新颖性。 复杂的，我们的初步研究确定为RBM 39的相互作用。