Dissecting the functional role of LINE1 retrotransposon-mediated interferon signaling in myeloid leukemia

剖析 LINE1 逆转录转座子介导的干扰素信号在髓系白血病中的功能作用

基本信息

批准号：
10536349
负责人：
Michael Lee
金额：
$ 3.77万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
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：
2022-07-18 至 2026-07-17
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10536349
关键词：
Ablation Acute Myelocytic Leukemia Address Adult Affect Apoptosis Biology CRISPR-mediated transcriptional activation Cell Aging Cell Cycle Arrest Cell Proliferation Clustered Regularly Interspaced Short Palindromic Repeats Complementary DNA DNA Dependence Development Double-Stranded RNA Elements Epigenetic Process Gene Expression Regulation Genetic Genetic Transcription Genetic study Genome Stability Genomic DNA Hematologic Neoplasms Hematopoiesis Hematopoietic Hematopoietic Neoplasms Human Immune Impairment In Vitro Individual Inflammation Innate Immune Response Interferon Activation Interferon Type I Interferons Jumping Genes Knockout Mice Knowledge Link Long Interspersed Elements MLL-AF9 Maintenance Malignant - descriptor Malignant Neoplasms Mediating Modeling Molecular Mus Myelogenous Myeloid Leukemia Natural Immunity Nature Nucleic Acids Pathogenesis Pathway interactions Patients RNA Reporting Repression Retrotransposition Retrotransposon Reverse Transcription Role Signal Pathway Signal Transduction Survival Rate Therapeutic Transcript Transgenic Mice Viral Work Xenograft procedure acute myeloid leukemia cell base cancer type chemotherapy clinical heterogeneity epigenetic silencing gene product in vivo inhibitor knock-down leukemia leukemia initiating cell leukemogenesis mimicry mouse model mutant novel therapeutics overexpression receptor response self-renewal sensor small hairpin RNA standard of care targeted treatment tumor tumorigenesis

项目摘要

PROJECT SUMMARY Acute myeloid leukemia (AML) is one of the most aggressive hematologic malignancies in adults, yet decades- old chemotherapies remain the standard of care and few targeted therapies exist owing to its molecular and clinical heterogeneity. An emerging hallmark of AML development is the epigenetic silencing of LINE1 retrotransposons which is required to maintain AML self-renewal, differentiation blockade, and genomic stability. Aberrant reactivation of LINE1 retrotransposons selectively impairs propagation of human and mouse AML cells without affecting normal hematopoiesis; however, it remains elusive how LINE1 activity inhibits myeloid leukemogenesis. Aberrant retrotransposon reactivation by cancer-targeting epigenetic inhibitors such as DNA hypomethylating agents (DMA) produces a type I interferon (IFN)-mediated ‘viral mimicry’ response in various cancer types, including leukemias, resulting in cell cycle arrest and apoptosis. We hypothesize that LINE1 retrotransposons contribute to the development of myeloid leukemia by modulating type I interferon signaling mediated by cGAS and/or RIG-I-like Receptor (RLR) sensing of LINE1 gene products. This proposal will establish the functional role of LINE1-mediated IFN signaling in myeloid leukemogenesis and determine the mechanisms by which LINE1 activates innate immune ‘viral mimicry’ pathways in AML cells. The Specific Aims of this proposal intend to 1) establish the functional role of LINE1-mediated interferon signaling in myeloid leukemogenesis and progression; and 2) identify the molecular sensors of LINE1-mediated interferon activation in AML. Ectopic LINE1 overexpression and CRISPR activation of endogenous LINE1s in human AML cells will determine whether LINE1 expression induces type I IFNs and impacts cell proliferation, myeloid differentiation, and/or apoptosis. Combining a conditional LINE1 activation transgenic mouse with the established MLL-AF9 retroviral leukemia model will determine whether activation of LINE1s induces hematopoietic-specific type I IFN to impair AML initiation and/or maintenance in vivo. Moreover, genetic ablation of cGAS, RIG-I, or MDA5 nucleic acid sensors individually or in combination in human AML cells and their corresponding knockout mouse models will determine how loss of DNA- and/or RNA-sensing pathways affects LINE1-induced inflammation and AML pathogenesis in vivo. Altogether, these stringent genetic studies will provide direct evidence to establish the functional role of LINE1-mediated IFN signaling in myeloid leukemia. Addressing these outstanding knowledge gaps will be critical to inform whether and how modulation of the retrotransposon-innate immunity crosstalk may be leveraged as a new mechanism-based therapeutic strategy to selectively eradicate AML cells.

项目摘要急性髓样白血病（AML）是成年人中最具侵略性的血液系统恶性肿瘤之一，但数十年 - 旧化学疗法仍然是护理的标准，由于其分子和临床异质性。 AML开发的新兴标志是Line1的表观遗传沉默逆转座子维持AML自我更新，分化阻滞和基因组稳定性所需。 Line1逆转座子的异常重新激活有选择地损害人和小鼠AML细胞的传播不影响正常的造血；但是，Line1活动如何抑制髓样仍难以捉摸白血病。鉴定癌症的表观遗传抑制剂（如DNA）异常逆转座子再激活在各种癌症类型，包括白血病，导致细胞周期停滞和凋亡。我们假设该行1 通过调节I型Interferon信号传导，逆转录座子有助于髓样白血病的发展由CGA和/或Line1基因产物的CGA和/或RIG-I样受体（RLR）介导。该提议将建立LINE1介导的IFN信号在髓样白血病发生中的功能作用，并确定 LINE1激活AML细胞中先天免疫“病毒模仿”途径的机制。具体目标 1）在髓样中建立线1介导的干扰素信号的功能作用白血病和进展； 2）确定线1介导的干扰素激活的分子传感器在AML。异位线1的过表达和人AML细胞中内源性线1的CRISPR激活将确定Line1表达是否诱导I型IFN并影响细胞增殖，髓样分化，和/或凋亡。将有条件的LINE1激活转基因小鼠与已建立的MLL-AF9结合逆转录病毒白血病模型将确定线条的激活是否诱导造血特异性I型IFN 为了损害AML的主动性和/或体内维护。此外，CGA，RIG-I或MDA5核酸的遗传消融酸传感器单独或组合在人AML细胞及其相应的基因敲除小鼠模型中将确定DNA-和/或RNA感应途径的损失如何影响线1诱导的注射和AML 体内发病机理。总之，这些严格的遗传研究将提供直接证据，以确定线1介导的IFN信号在髓样白血病中的功能作用。解决这些杰出知识差距对于告知逆转录座免疫串扰的调节以及如何调节可能是至关重要的将其作为一种基于机制的新理论策略，以选择性地放射AML细胞。