The role of Abelson interactor 1 (Abi-1) in hematopoietic stem cell self-renewal and malignant transformation

Abelson相互作用子1（Abi-1）在造血干细胞自我更新和恶性转化中的作用

• 批准号: 10447020
• 负责人: Patrycja Marta Dubielecka-Szczerba
• 金额: $ 36.09万
• 依托单位: RHODE ISLAND HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-24 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10447020
• 关键词: Actins; Adaptor Signaling Protein; Affect; Attention; Blood; Bone Marrow; Cell Proliferation Regulation; Cells; Clinical; Communication; Complement; Critical Pathways; Data; Development; Disease; Embryo; Event; Genes; Goals; Heart Abnormalities; Hematopoietic; Hematopoietic System; Hematopoietic stem cells; Homeostasis; Human; Impairment; Inflammation; Inflammatory; JAK2 gene; Knockout Mice; Knowledge; Label; MAP Kinase Gene; Maintenance; Malignant - descriptor; Mediating; Modeling; Mus; Mutation; Myeloproliferative disease; NF-kappa B; Neoplasms; Pathogenesis; Pathogenicity; Pathway interactions; Patients; Phenotype; Phosphotransferases; Placenta; Play; Primary Myelofibrosis; Process; Proteins; Proteomics; Regulation; Research; Role; STAT3 gene; Signal Pathway; Signal Transduction; Technology; Testing; Therapeutic; Transcript; base; cancer stem cell; curative treatments; disease natural history; fitness; granulocyte; hematopoietic stem cell self-renewal; inhibitor; insight; mouse model; novel; novel therapeutic intervention; phosphoproteomics; polymerization; response; self-renewal; src-Family Kinases; stem; stem cells; therapeutic target; translational goal

PROJECT SUMMARY/ABSTRACT It is well established that JAK/STAT signaling is dysregulated in most myeloid malignancies. Identification of JAK-activating mutations in myeloproliferative neoplasms (MPNs) prompted the development of inhibitors that target JAK for use in the clinical setting. While these agents provide a symptomatic response, they do not alter the underlying disease in that they do not target MPN-initiating malignant hematopoietic stem/progenitor cells (HSPCs). This observation has been interpreted as indicating that alternative signaling pathways contribute to the pathogenesis of MPNs. The present proposal is based on the premise that identification of hitherto unknown pathogenic mechanisms will be required to effectively treat these neoplasms and eradicate disease initiating MPN stem cells. Our long-term goal is to define signal transduction events responsible for systemic maintenance of HSPCs, with particular focus on key adapter proteins that modulate signals regulating HSPCs self-renewal, differentiation and their malignant transformation. Our direct objective is to elucidate the role of one such adapter protein, Abelson interactor-1 (Abi-1), in signaling cascades that define the HSPC phenotype. Our recent findings indicate that: (1) conditional deletion of the Abi1 gene in mouse bone marrow induces a myelofibrotic phenotype; (2) hematopoietic progenitors and granulocytes from patients with the most severe of MPNs - primary myelofibrosis (PMF) show decreased Abi-1 transcript and protein levels, and; (3) loss of Abi-1 positively affects the activity of Src Family Kinases (SFKs) and their downstream signaling to STAT3 and NF- κB, resulting in impairment of HSPC self-renewal and fitness. Our central hypothesis is that Abi-1 plays an important and potentially targetable role in HSPC self-renewal and differentiation via negative regulation of the SFK/STAT3/NF-κB inflammatory module, and that its acquired absence can promote malignant transformation and progression to PMF. Our central hypothesis will be tested in the following three Specific Aims. In Specific Aim 1 we will use our new hematopoietic cell-specific Abi-1 knockout mouse model to determine the effect of Abi-1 loss on HSPC signaling and self-renewal, differentiation and malignant transformation. In Specific Aim 2, we will use advanced proteomics combined with proximity-dependent labelling technology to define the Abi-1 interactome in HSPCs. This approach will be complemented by phosphoproteomic analyses of Abi-1-deficient HSPCs and human PMF stem/progenitor cells. In Specific Aim 3 we will use our bone marrow stroma-specific Abi-1 knockout mouse model to assess the effect of deletion of Abi-1 in the stromal component on the self-renewal, differentiation and malignant transformation of HSPCs. Completion of the proposed aims will advance our understanding of the mechanisms by which dysregulation of Abi-1/SFK/STAT3/NF-kB signaling contributes to the neoplasm-inducing capacities of HSPCs. This new knowledge will be used to make progress toward our long-term translational goal of identifying therapeutic strategies that target cells responsible for the origin of myeloproliferative neoplasms.

项目总结/摘要 已经确定JAK/STAT信号传导在大多数骨髓恶性肿瘤中失调。鉴定 骨髓增生性肿瘤（MPN）中的JAK激活突变促使抑制剂的开发， 靶向JAK用于临床环境。虽然这些药物提供了症状反应，但它们不会改变 潜在的疾病，因为它们不靶向MPN起始的恶性造血干/祖细胞 （HSPC）。这一观察结果已被解释为表明替代信号通路有助于 MPN的发病机制。目前的建议是基于这样一个前提， 需要未知的致病机制来有效治疗这些肿瘤并根除疾病 启动MPN干细胞。我们的长期目标是确定负责系统性的信号转导事件， HSPC的维持，特别关注调节HSPC信号的关键衔接蛋白 自我更新、分化及其恶性转化。我们的直接目标是阐明 一种这样的衔接蛋白，Abelson相互作用子-1（Abi-1），在定义HSPC表型的信号级联中。 我们最近的研究结果表明：（1）小鼠骨髓中Abi 1基因的条件性缺失诱导了一种新的细胞凋亡， 骨髓纤维化表型;（2）来自患有最严重骨髓纤维化表型的患者的造血祖细胞和粒细胞。 MPN-原发性骨髓纤维化（PMF）显示降低的Abi-1转录物和蛋白质水平，以及;（3）Abi-1缺失 积极影响Src家族激酶（SFK）的活性及其下游信号转导至STAT3和NF-κ B。 κ B，导致HSPC自我更新和适应性受损。我们的核心假设是阿比-1在 在HSPC自我更新和分化中通过负调节 SFK/STAT3/NF-κ B炎症模块，其获得性缺失可促进恶性肿瘤的发生， 向PMF的转变和发展。我们的中心假设将在以下三个具体的测试中得到验证。 目标。在Specific Aim 1中，我们将使用我们新的造血细胞特异性Abi-1基因敲除小鼠模型， 确定Abi-1缺失对HSPC信号传导和自我更新、分化和恶性肿瘤的影响。 转型在具体目标2中，我们将使用先进的蛋白质组学结合邻近依赖 标记技术来定义HSPC中的Abi-1相互作用组。这一做法将得到以下方面的补充： Abi-1缺陷型HSPC和人PMF干/祖细胞的磷酸蛋白质组学分析。具体目标 3我们将使用我们的骨髓基质特异性Abi-1敲除小鼠模型来评估缺失Abi-1基因的影响。 Abi-1在HSPCs的自我更新、分化和恶性转化中的作用 完成所提出的目标将促进我们的机制，失调的理解， Abi-1/SFK/STAT3/NF-kB信号通路参与了HSPC的肿瘤诱导能力。这个新 知识将被用于实现我们的长期转化目标， 靶向负责骨髓增生性肿瘤起源的细胞的策略。