Developing small molecule inhibitors of Pleckstrin-2 to treat thrombosis

开发 Pleckstrin-2 小分子抑制剂来治疗血栓形成

• 批准号: 10545992
• 负责人: Jing Yang
• 金额: $ 39.72万
• 依托单位: APLEXIS, INC.
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-15 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10545992
• 关键词: Anemia; Arteries; Aspirin; Binding; Binding Proteins; Biological Assay; Biometry; Blood Cell Count; Blood Vessels; Bone Marrow; Cell Proliferation; Cells; Chemistry; Chronic; Chronic Phase; Clinical Management; Clinical Trials; Collaborations; Complication; Data; Development; Disease; Drug Kinetics; Ensure; Erythroblasts; Erythropoietin; FDA approved; Foundations; Future; Generations; Genetic study; Goals; Hematopoiesis; Hemorrhage; Hemorrhagic Thrombocythemia; Impairment; In Vitro; Injections; Intellectual Property; Interferon-alpha; Investigation; JAK2 gene; Knock-in; Knock-in Mouse; Knock-out; Laboratories; Lead; Legal patent; Letters; Licensing; Mediating; Membrane; Modeling; Morbidity - disease rate; Mus; Mutation; Myeloproliferation; Myeloproliferative disease; Names; Neutrophilia; Pathogenesis; Pathway interactions; Patients; Peripheral Blood Mononuclear Cell; Pharmaceutical Chemistry; Phase; Phenotype; Phosphatidylinositols; Polycythemia Vera; Positioning Attribute; Primary Myelofibrosis; Production; Proteins; Quality of life; Research; Reticulocytosis; Risk; Role; Scaffolding Protein; Signal Transduction; Site; Small Business Innovation Research Grant; Spleen; Splenomegaly; Stat5 protein; Technology; Testing; Therapeutic Effect; Thrombocytopenia; Thrombosis; Toxic effect; Universities; Veins; base; clinical candidate; effective therapy; efficacy evaluation; experimental study; high throughput screening; hydroxyurea; improved; in silico; in vivo; inhibitor; innovation; molecular targeted therapies; mortality; mouse genetics; mouse model; mutant; new therapeutic target; novel; novel strategies; novel therapeutic intervention; overexpression; pharmacokinetics and pharmacodynamics; platelet protein P47; pre-clinical; prevent; recruit; side effect; small molecule; small molecule inhibitor; success; thrombocytosis

PROJECT SUMMARY Thrombosis, often at unusual sites such as splanchnic vein and arteries, is common complication and one of the leading causes of mortality and morbidity in patients with chronic myeloproliferative neoplasms (MPNs). Developing effective therapies for thrombosis in MPNs is in its nascence. Current first-line therapy of chronic phase MPNs includes aspirin, hydroxyurea, interferon a, or anagrelide. However, these treatment approaches remain suboptimal with ongoing risks for thrombosis, hemorrhage, and impaired quality of life. Targeted molecular therapy at this stage of MPNs for thrombosis is also lacking. Aplexis, Inc is a startup company focusing on the development of new approaches to treat thrombosis in the chronic phase of MPNs, especially targeting the downstream effectors of the JAK2 pathway that is commonly activated in these disorders. One of these effectors is Pleckstrin-2 (Plek2) that is a novel target of the JAK2-STAT5 pathway. Previous studies have shown that loss of Plek2 ameliorated JAK2V617F mutant-induced myeloproliferative phenotypes, and reverted thrombosis and lethality of the JAK2V617F MPN mouse model. Importantly, Plek2 is overexpressed in the bone marrow and peripheral blood mononuclear cells from JAK2V617F positive chronic MPN patients. Given the significance of Plek2 in thrombosis pathogenesis in MPNs, the Ji laboratory at Northwestern University has identified hit compounds of Plek2 small molecule inhibitors using in silico-based high-throughput screenings and cell-based assays. Preliminary data show that the hit compounds significantly inhibit Plek2’s functions on erythroblast proliferation and lamellipodia formation in vitro. The hit compounds also dramatically reduce myeloproliferation and thrombosis in vivo in MPN mouse models. Preliminary mechanistic studies reveal that Plek2 functions as a scaffold protein to recruit PI3K effector proteins and enhances PI3K-Akt signaling. Plek2 inhibitors bind to Plek2 and disrupt this recruitment, which blocks PI3K-Akt signaling and inhibits cell hyperproliferation. Together, these findings lead us to hypothesize that Plek2 inhibitors block cell hyperproliferation in vitro and in vivo and prevent thrombosis in MPNs. The goal of this Phase I SBIR project is to establish proof-of-principle evidence for the therapeutic effects of Plek2 inhibitors in thrombosis in MPNs. In Aim 1, we propose to develop lead compounds with potent inhibitory effects of Plek2-induced cell proliferation in vitro using medicinal chemistry and cell-based assays. In Aim 2, we will examine the efficacy, pharmacokinetics, and toxicity of lead compounds in pre-clinical MPN mouse models with thrombosis. Aplexis has a strong support from Northwestern University’s Innovation and New Ventures Office (INVO) on an exclusive license for the associated patent-pending intellectual property from this technology. The collaboration with the Ji laboratory at Northwestern University will ensure the success of the proposed research, which will position Aplexis to the next step in the production of clinical candidate of Plek2 inhibitors and pre-IND investigation in Phase II.

项目概要 血栓形成通常发生在内脏静脉和动脉等不寻常部位，是常见的并发症，也是血栓形成的原因之一。 慢性骨髓增生性肿瘤（MPN）患者死亡和发病的主要原因。 开发针对 MPN 血栓形成的有效疗法尚处于起步阶段。目前慢性病的一线治疗 相 MPN 包括阿司匹林、羟基脲、干扰素 a 或阿那格雷。然而这些治疗方法 仍处于次优状态，存在血栓形成、出血和生活质量受损的持续风险。有针对性 现阶段还缺乏针对 MPN 血栓形成的分子治疗。 Aplexis, Inc 是一家初创公司 专注于开发治疗 MPN 慢性期血栓形成的新方法，特别是 靶向在这些疾病中通常被激活的 JAK2 通路的下游效应器。之一 这些效应子是 Pleckstrin-2 (Plek2)，它是 JAK2-STAT5 通路的新靶标。之前的研究有 研究表明，Plek2 的缺失改善了 JAK2V617F 突变体诱导的骨髓增殖表型，并恢复了 JAK2V617F MPN 小鼠模型的血栓形成和致死率。重要的是，Plek2 在骨骼中过度表达 来自 JAK2V617F 阳性慢性 MPN 患者的骨髓和外周血单核细胞。鉴于 西北大学季实验室研究了 Plek2 在 MPN 血栓形成发病机制中的意义 在基于计算机的高通量筛选中鉴定出 Plek2 小分子抑制剂的命中化合物 和基于细胞的测定。初步数据表明，命中化合物显着抑制 Plek2 的功能 体外成红细胞增殖和片状伪足形成。命中化合物也大大减少 MPN 小鼠模型中的骨髓增殖和体内血栓形成。初步机制研究表明 Plek2 作为支架蛋白来招募 PI3K 效应蛋白并增强 PI3K-Akt 信号传导。普莱克2 抑制剂与 Plek2 结合并破坏这种募集，从而阻断 PI3K-Akt 信号传导并抑制细胞 过度增殖。总之，这些发现使我们推测 Plek2 抑制剂会阻断细胞 体外和体内过度增殖并预防 MPN 中的血栓形成。第一阶段 SBIR 项目的目标是 为 Plek2 抑制剂对 MPN 血栓形成的治疗效果建立原理验证证据。在 目标 1，我们建议开发对 Plek2 诱导的细胞增殖具有有效抑制作用的先导化合物 使用药物化学和基于细胞的测定在体外进行。在目标 2 中，我们将检查功效， 先导化合物在临床前 MPN 小鼠血栓模型中的药代动力学和毒性。丛属 得到了西北大学创新与新创企业办公室（INVO）的大力支持 该技术相关正在申请专利的知识产权的独家许可。合作 与西北大学季实验室的合作将确保拟议研究的成功，这将 使 Aplexis 进入 Plek2 抑制剂临床候选药物和 pre-IND 生产的下一步 第二阶段调查。