Mechanisms of Leukemogenesis in AMKL

AMKL 白血病发生机制

• 批准号: 10845929
• 负责人: Stephanie Halene
• 金额: $ 66.24万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10845929
• 关键词: Acute Megakaryocytic Leukemias; Affect; Animal Model; Binding; Biological; Biological Assay; Cell Death; Cell Line; Cells; Chimeric Proteins; Chromatin; Complex; Coupled; DNA; Data; Data Set; Dependence; Development; Disease; Dominant-Negative Mutation; Doxycycline; Event; Fetal Liver; Fusion Protein Expression; Gene Expression; Genes; Genetic Engineering; Genetic Transcription; Genomic approach; Growth; Hematopoietic; Human; Immunoprecipitation; Individual; Knock-in Mouse; Light; Link; Malignant Neoplasms; Maps; Mediating; Megakaryocytes; Messenger RNA; Methylation; Methyltransferase; Mission; Modeling; Modification; Molecular; Mus; Mutation; Oncogenes; Oncogenic; Pathway interactions; Patients; Play; Publishing; RNA; RNA Stability; RNA metabolism; RNA methylation; Recurrence; Regulation; Role; Sampling; Serum Response Factor; Site; Testing; Therapeutic; Transcript; Translations; United States National Institutes of Health; Xenograft procedure; acute megakaryoblastic leukemia cell; cancer type; clinically relevant; cofactor; crosslink; epitranscriptome; genome-wide analysis; improved; inducible gene expression; innovation; insight; leukemia; leukemogenesis; novel; overexpression; posttranscriptional; prevent; programs; promoter; recruit; response; tRNA Methyltransferases; transcription factor; transcriptome sequencing; translatome; treatment optimization; tumorigenesis

Project Summary/Abstract Fundamental analysis of the mechanisms of leukemogenesis is required in order to develop optimized treatment approaches. N6-methyladenosine (m6A), the most abundant RNA modification, plays key roles in RNA metabolism, transcript stability, and translation efficiency. Aberrant regulation of m6A writers and erasers contributes to leukemogenesis, though the exact mechanisms how the methyltransferase machinery is altered in leukemia remains to be shown. Mutations in methyltransferase writers have not been identified to date, with one exception: in the recurrent t(1;22) translocation in acute megakaryoblastic leukemia (AMKL) a component of the m6A writer machinery, RBM15, is fused with MKL1, a transcriptional cofactor of serum response factor (SRF). Understanding the mechanism by which the RBM15-MKL1 (RM) fusion protein causes leukemia will shed light on the role of disordered m6A RNA methylation in leukemogenesis, specifically AMKL but also AML and to cancer in general. We hypothesize that for RM-associated AMKL to develop, the MKL1 domain aberrantly targets RBM15 activity to sites of SRF binding and that RBM15 recruits the m6A writer complex to associated RNAs, altering m6A mRNA methylation and expression of genes that are required for transformation and/or are important for megakaryocyte fate commitment and maturation. We propose focused, unbiased genome-wide studies to determine how the m6A epitranscriptome and the SRF transcriptional networks are coopted in RBM15- MKL1 AMKL. The functional effects of candidate target genes common to the genomic approaches (m6A RNA immunoprecipitation, chromatin mapping, RNA stability assays, and mapping of the translatome) as well as the relevance of critical domains in RM-mediated leukemogenesis will be tested with assays of growth, differentiation and oncogene dependence in RM-induced murine AMKL as well as primary human AMKL patient derived xenotransplants (PDX). The studies are highly clinically relevant as they address a unique mechanism causative of AMKL via comprehensive analysis of fundamental biologic mechanisms, and will reveal previously unidentified regulation of the epitranscriptome that may be a novel shared oncogenic mechanism in AML and other cancers. The proposed approaches are multifaceted, using cell lines as well as genetically engineered animal models, and primary human and murine leukemia samples. The studies will contribute to our understanding of leukemogenesis by elucidating the direct role of a component of the m6A RNA methylase complex in leukemia shedding light on the broader role of m6A mRNA modifications in AML.

项目摘要/摘要 为了开发优化，需要对白血病机理的基本分析 治疗方法。 N6-甲基腺苷（M6A），最丰富的RNA修饰，在 RNA代谢，转录本稳定性和翻译效率。 M6A作家和橡皮擦的异常法规 尽管确切的机制是如何改变甲基转移酶的，但有助于白血病。 在白血病中，仍有待表现。迄今尚未确定甲基转移酶作者的突变， 一个例外：在急性巨型细胞白血病（AMKL）的复发t（1; 22）中 M6A作者机械RBM15与MKL1融合，MKL1是血清响应因子的转录辅助因子 （SRF）。了解RBM15-MKL1（RM）融合蛋白导致白血病的机理 阐明了无序的M6a RNA甲基化在白血病发生中的作用，特别是AMKL，也是AML和TO 一般而言。我们假设为了开发与RM相关的AMKL，MKL1域异常目标 RBM15活性对SRF结合的位点，RBM15将M6A作者复合物募集到相关的RNA， 改变M6A mRNA甲基化和转化所需的基因表达和/或 对于巨核细胞命运的承诺和成熟至关重要。我们提出了集中，无偏基因组的集中 研究以确定M6A的表演组和SRF转录网络如何在RBM15-- MKL1 AMKL。基因组方法共有的候选靶基因的功能效应（M6A RNA 免疫沉淀，染色质映射，RNA稳定性测定和翻译组的映射）以及 关键域在RM介导的白血病中的相关性将通过生长，分化测定法测试 RM诱导的鼠AMKL和原代人AMKL患者的癌基因依赖性 异种移植（PDX）。这些研究在临床上高度相关，因为它们解决了独特的机制。 通过对基本生物学机制的全面分析AMKL，并将揭示先前未识别的 调节表参见组可能是AML和其他癌症中一种新型的共同致癌机制。 提出的方法是多方面的，使用细胞系以及基因工程的动物模型， 以及原发性和鼠白血病样品。研究将有助于我们的理解 通过阐明白血病中M6A RNA甲基酶复合物的直接作用的白血病发生 阐明了M6A mRNA修饰在AML中的更广泛作用。