Mechanism of thrombosis in two myeloproliferative neoplasms (MPNs), polycythemia vera and essential thrombocythemia

两种骨髓增生性肿瘤（MPN）、真性红细胞增多症和原发性血小板增多症的血栓形成机制

• 批准号: 10699552
• 负责人: JOSEF T PRCHAL
• 金额: --
• 依托单位: VA SALT LAKE CITY HEALTHCARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10699552
• 关键词: Adult; Blood; Blood Cell Count; Blood Cells; Blood Platelets; Blood coagulation; Bone Marrow Cells; Cell Line; Cells; Cessation of life; Child; Clinical; Colony-forming units; Congenital Disorders; Data; Development; Disease; EDN1 gene; Endothelial Cells; Endothelium; Environment; Enzymes; Erythrocytes; Erythrocytoses; Gene Expression; Genes; Genetic Transcription; Goals; Hematocrit procedure; Hematopoietic; Hematopoietic Neoplasms; Hemorrhagic Thrombocythemia; Home; Hospitalization; Hypoxia; Incidence; Inflammation; Inflammatory; Iron; JAK1 gene; JAK2 gene; Laboratory Finding; Legal patent; Leukocytes; MPL gene; Mediating; Messenger RNA; Molecular; Morbidity - disease rate; Multivariate Analysis; Mutate; Mutation; Myeloproliferative disease; Patients; Persons; Physicians; Play; Polycythemia; Polycythemia Vera; Prevention; Procollagen-Proline Dioxygenase; Protein S; Publishing; Recording of previous events; Registries; Regulation; Research; Risk; Role; Signal Transduction; Somatic Mutation; Source; Testing; Thromboplastin; Thrombosis; Transcript; Up-Regulation; VHL mutation; Venous Thrombosis; Venous blood sampling; White Blood Cell Count procedure; Work; Zinc Fingers; calreticulin; cancer type; chronic leukemia; cofactor; follow-up; granulocyte; hypoxia inducible factor 1; inhibitor; interest; iron deficiency; monocyte; mortality; neutrophil; new therapeutic target; novel; premature; prevent; prospective; stem cells; thrombotic; transcription factor

Project Summary/Abstract Arterial and venous thromboses are the major causes of morbidity and mortality in in two myeloproliferative neoplasms (MPNs): polycythemia vera (PV) and essential thrombocythemia (ET), associated with JAK2, and in ET in addition to JAK2 also calreticulin (CALR), and infrequently thrombopoietin receptor (cMPL) somatic mutations. However, the molecular mechanism of thrombosis is largely unknown. In multivariate analyses, the leukocyte count independently correlates with their risk of thromboses. Our published work demonstrates that the hypoxia inducible transcription factors (HIF-1 and HIF-2), which are upregulated in both granulocytes and platelets in PV and ET, promote the transcription of prothrombotic and proinflammatory genes. Leukocytes are the only source of tissue factor (TF) in the blood, and we also showed that PV neutrophils constitutively express TF activity. Transcripts of Krüppel-like Factor 2 (KLF2) - a zinc finger transcription factor, are down regulated in granulocytes and platelets from PV and ET patients and correlate inversely with the transcripts of prothrombotic genes, suggesting that KLF2 might be a suppressor of thrombotic gene expression in these conditions. In Chuvash erythrocytosis/polycythemia (CE) - a congenital disorder associated with increased HIF-1 and HIF-2 due to a hypomorphic R200W mutation of the Von Hippel- Lindau (VHL) gene, the incidence of thrombosis is higher than in PV and phlebotomy did not prevent thrombosis but instead appeared to have facilitated it. Repeated phlebotomies induced iron deficiency (ID) which further increased the level of HIF-1 and HIF-2 by inhibiting the negative HIFs regulator prolyl hydroxylase domain 2 (PHD2) enzyme, which requires iron as a co-factor. Therefore, we hypothesize that the up-regulation of HIF signaling in ET and PV granulocytes and platelets, perhaps with an additional contribution of augmented inflammation, plays a central role in the development of thrombosis. In order to achieve our objective, we propose to follow these specific aims (SA): SA 1a. Determine whether the correction of ID decreases HIF signaling and ameliorates the thrombotic milieu in PV and ET. SA 1b. Determine the effect of HIFs in PV and ET thrombosis using inhibitors of HIF-1, HIF2 and JAKs. SA 2. Extend our observations from mRNA transcripts of HIF-regulated, prothrombotic and antithrombotic genes and inflammatory genes to the activity of TF in all blood lineages. SA 3. Determine the role of KLF2 in increasing the risk of thrombosis in PV and ET and its regulation and elucidate in more detail the interaction of KLF2 and HIFs. We submit that proving our hypothesis will uncover novel mechanisms of thrombosis in PV and ET and open new therapeutic targets for prevention of thrombosis in PV and ET.

项目总结/摘要 动脉和静脉血栓形成是两个国家发病和死亡的主要原因 骨髓增生性肿瘤（MPN）：真性红细胞增多症（PV）和原发性血小板增多症（ET）， 与JAK 2相关，在ET中，除了JAK 2外，还存在钙网蛋白（CALR）， 血小板生成素受体（cMPL）体细胞突变。然而， 血栓形成基本上是未知的。在多变量分析中，白细胞计数独立相关 有血栓形成的风险我们已发表的工作表明，缺氧可诱导 转录因子（HIF-1和HIF-2），它们在粒细胞和血小板中上调， PV和ET促进促血栓形成和促炎基因的转录。白细胞 组织因子（TF）在血液中的唯一来源，我们还表明，PV中性粒细胞组成性 表达TF活性。Krüppel样因子2（KLF 2）-锌指转录因子的转录物， 在PV和ET患者的粒细胞和血小板中下调，并与 提示KLF 2可能是血栓形成基因的抑制因子 在这些条件下表达。在楚瓦什红细胞增多症/红细胞增多症（CE）-一种先天性疾病 与由于Von Hippel的亚型R200 W突变引起的HIF-1和HIF-2增加相关， Lindau（VHL）基因，血栓形成的发生率高于PV，而静脉切开术未预防 血栓形成，但相反似乎促进了它。反复抽血诱发缺铁 (ID)通过抑制HIF-1和HIF-2的负调节因子， 脯氨酰羟化酶结构域2（PHD 2）酶，其需要铁作为辅因子。所以我们 假设ET和PV粒细胞和血小板中HIF信号的上调， 与增加的炎症的额外贡献，在发展中起着核心作用， 血栓形成为了实现我们的目标，我们建议遵循这些具体目标（SA）： SA 1a.确定ID的纠正是否减少HIF信号传导并改善血栓形成。 PV和ET中的环境。 SA 1b.使用HIF-1、HIF 2和JAK抑制剂确定HIF在PV和ET血栓形成中的作用。 SA 2.从HIF-1 α调节的、血栓形成前的和 抗血栓基因和炎症基因对所有血液谱系中TF活性的影响。 SA 3.确定KLF 2在增加PV和ET血栓形成风险中的作用及其调节 并更详细地阐明KLF 2和HIF的相互作用。 我们认为，证明我们的假设将揭示新的机制，血栓形成的PV和ET 为预防PV和ET血栓形成开辟了新的治疗靶点。