Hematopoiesis in germline RUNX1mutation carriers: impact of inflammation and the bone marrow niche

造血术 影响 生殖系RUNX1突变携带者： 炎症和骨髓巢的关系 项目摘要/摘要 导致白血病风险的生殖系变异已经被越来越多的人认识到，15%-20%的急性 白血病患者有至少1个一级亲属患白血病。生殖系变种现在是 首次包括在世界卫生组织概述的修订的白血病分类方案中 组织，新的临床指南现在包括遗传易感性测试作为 病人诊断学。对于这些患者和他们的家人来说，生活在知道 一生中罹患癌症的风险增加。因此，对于这些患者来说，早期癌症检测， 疾病监测和预防将改变人们的生活，但需要全面了解 在显性白血病之前发生的分子变化。这项研究的长期目标是确定 生殖系RUNX1突变患者癌前阶段的造血调控机制 [也称为家族性血小板紊乱(FPD)]。这些人患有终生的血小板减少症，定性的 血小板聚集缺陷，以及发展为各种血液系统恶性肿瘤的风险。此次收购 随着时间的推移，FPD患者中会发生许多继发性突变，从而导致白血病的发生。然而， 使白血病前期细胞容易获得二次突变的内在和/或外在因素有 未知。为了填补这一知识空白，我们对原始FPD骨进行了单细胞转录组分析 与健康对照的FPD祖细胞的骨髓样本和独特的转录变化 控制。与这些变化一致的是，FPD祖细胞损害了巨核细胞，但增强了髓系 差异化。骨髓间充质干细胞和造血细胞的细胞因子图谱显示 骨髓中细胞因子的产生增加，导致慢性炎症应激， 这可能会给FPD的祖细胞带来生长优势。此外，FPD间质细胞也显示出缺陷 分化、克隆形成能力和不受调控的基因表达可能进一步促进 炎症状态。因此，我们假设FPD干/祖细胞的早期转录改变 配合炎症微环境信号，为这些白血病前期患者提供生长优势 并改变它们的分化。我们将通过以下目标来验证我们的假设：1)确定多早 转录改变改变了FPD细胞的造血。2)确定炎性细胞因子的影响 以及他们在FPD发展过程中的阻碍。3)评估FPD间质微环境对生长和 FPD与健康干/祖细胞的分化。为了实现我们的目标，我们已经组装了几个工具， 包括原代干细胞/祖细胞和基质细胞、IPSCs、异种移植和转基因小鼠模型， CRISPR/CAS9 造血术 靶向性 和 编辑技术，以及3D共培养模型。这个项目将增进我们对 将为合理设计新的治疗方法提供分子基础 RUNX1介导的变化和炎症微环境对正常造血的影响 延缓或预防FPD患者的白血病。

Hematopoiesis impact in germline RUNX1 mutation carriers: of inflammation and the bone marrow niche PROJECT SUMMARY/ABSTRACT Germline variants that confer risk for leukemia have been recognized increasingly with 15-20% of acute leukemia patients having at least 1 first-degree relative afflicted with leukemia. Germline variants are now included for the first time in the revised leukemia classification scheme outlined by the World Health Organization, and new clinical guidelines now include testing for inherited susceptibility as a critical element of patient diagnostics. It is devastating for these patients and their family members to live with the knowledge of having increased risk for developing cancer in their lifetimes. Thus, for these patients, early cancer detection, disease monitoring, and prevention would be life-changing, but require a comprehensive understanding of molecular changes that occur prior to overt leukemia. The long-term goal of this study is to identify the mechanisms that regulate hematopoiesis at the premalignant stage in patients with germline RUNX1 mutations [also called familial platelet disorder (FPD)]. These individuals have life-long thrombocytopenia, qualitative platelet aggregation defects, and a risk of developing a variety of hematopoietic malignancies. The acquisition of secondary mutations occurs over time in FPD patients leading to leukemia development. However, the intrinsic and/or extrinsic factors that render pre-leukemic cells vulnerable to acquire secondary mutations are unknown. To fill this knowledge gap, we performed single-cell transcriptome profiling of primary FPD bone marrow samples and identified unique transcriptional changes in FPD progenitors compared to healthy controls. Consistent these changes, FPD progenitors have impaired megakaryocytic but enhanced myeloid differentiation. Cytokine profiling of bone marrow hematopoietic and mesenchymal stromal cells (MSCs) show that there is increased cytokine production within the bone marrow, leading to chronic inflammatory stress, which may confer a growth advantage to FPD progenitors. Moreover, FPD stromal cells also show defective differentiation, clonogenic capacity, and deregulated gene expression that may further promote an inflammatory state. Thus, we hypothesize that early transcriptomic changes in FPD stem/progenitors cooperate with inflammatory microenvironmental signals to provide a growth advantage to these pre-leukemic cells and alter their differentiation. Wewill test our hypothesis using the following aims: 1)Identify how early transcriptomic changes alter hematopoiesis of FPD cells. 2) Determine the impact of inflammatory cytokines and their blockade in FPD evolution. 3) Assess the role of the FPD stromal microenvironment on growth and differentiation of FPD and healthy stem/progenitors. To achieve our goals, we have assembled several tools, including primary stem/progenitor/and stromal cells, iPSCs, xenograft and transgenic mouse models, CRISPR/Cas9 hematopoiesis targeting and editing technique, and 3D co-culture models. This project will advance our understanding of in FPD patients and will provide the molecular basis for the rational design of new therapeutics of RUNX1-mediated changes and the inflammatory microenvironment to normalize hematopoiesis delay or prevent leukemia in FPD patients.