A Targeted Combination Therapy Approach for AML

AML 的靶向联合治疗方法

• 批准号: 10047167
• 负责人: Dawn Elizabeth Barnes
• 金额: $ 15.6万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10047167
• 关键词: 3-Dimensional; ABCG2 gene; Acute Myelocytic Leukemia; Address; Adult; Adult Acute Myeloblastic Leukemia; Affinity; Apoptosis; Biomimetics; Blood; Bone Marrow; Bone Marrow Diseases; Cell Cycle Progression; Cell Death; Cell Density; Cell Line; Cells; Cellular Metabolic Process; Cessation of life; Chemotaxis; Childhood; Combined Modality Therapy; Cytotoxic Chemotherapy; Data; Development; Down-Regulation; Doxorubicin; Etoposide; Goals; Hematopoiesis; Homing; Human; In Vitro; Induction of Apoptosis; Integrins; Lead; Leukemic Cell; Leukocytes; Libraries; MERTK gene; Measures; Mediating; Mediator of activation protein; Modeling; Molecular; Molecular Target; Morbidity - disease rate; Mus; Oncogenes; Pancytopenia; Patients; Phase I Clinical Trials; Pre-Clinical Model; Protein Kinase; Protein Tyrosine Kinase; Quality of life; ROCK1 gene; Receptor Protein-Tyrosine Kinases; Relapse; Resistance; Resistance development; Sampling; Signal Pathway; Spleen; Stream; Stromal Cells; Survival Rate; Testing; Therapeutic; Therapeutic Effect; Tissues; Toxic effect; Treatment Efficacy; Treatment Protocols; Work; Xenograft Model; Xenograft procedure; acute myeloid leukemia cell; burden of illness; chemokine; chemotherapy; drug efficacy; experimental study; fetal liver kinase-2; hematopoietic differentiation; improved; improved outcome; inhibitor/antagonist; innovation; kinase inhibitor; leukemia; leukemogenesis; metabolomics; molecular targeted therapies; mortality; mouse model; novel; older patient; outcome forecast; patient response; pediatric patients; pre-clinical; preclinical study; prevent; research clinical testing; response; rho; side effect; small hairpin RNA; small molecule; small molecule inhibitor; synergism; targeted treatment; therapeutic evaluation; therapeutic target; tumor

PROJECT SUMMARY/ ABSTRACT Treatment of acute myeloid leukemia (AML) has improved but five-year survival rates are still <60% for adult and pediatric patients. Current therapies are very toxic, can cause long-term side effects, and are often contraindicated for elderly patients. Our goal is to develop a molecularly-targeted therapy for AML with better efficacy and reduced toxicity. MERTK tyrosine kinase is ectopically expressed in >90% of pediatric and adult AML patient samples. MRX-2843 is a novel small molecule that inhibits MERTK and FLT3, a known therapeutic target in AML. MRX-2843 has robust activity in preclinical models and is currently in phase I clinical trials; however, the utility of molecularly-targeted monotherapies has been limited by development of resistance. Thus, we sought to identify signaling pathways that synergize with MRX-2843 to inhibit leukemia cell expansion. Using a kinase inhibitor library screen, we found synergistic interactions between MRX-2843 and RKI-1447, an inhibitor of rho-associated protein kinases (ROCK1 and ROCK2). ROCK1 down-regulation reduces leukocyte affinity for chemokines in the protective bone marrow niche and ROCK inhibition reduces expansion of AML blasts in patient sample cultures, induces AML cell death, and prolongs survival in murine AML models. MRX-2843/RKI-1447 combination therapy synergistically reduced AML cell expansion in vitro and these effects correlated with changes in cell cycle progression and induction of apoptosis. Preliminary data also suggest that ROCK1/2 inhibition can promote AML sensitivity to MRX-2843 in the bone marrow. We hypothesize that simultaneous inhibition of ROCK1/2 and MERTK/FLT3 will decrease disease burden and prolong survival, both alone and in combination with standard AML induction chemotherapy, in murine AML models. To test this idea, the impact of treatment with MRX-2843, GSK269962A, and/or chemotherapy will be determined in mice with human AML cell line and/or patient derived xenografts. To identify the targets important for therapeutic synergy, shRNA-expressing cell line derivatives (shMERTK, shROCK1, shROCK2, shCONTROL) will be tested in xenograft models in combination with MRX-2843, GSK269962A, or vehicle. To further evaluate the ability of the combination therapy to target bone marrow disease, the impact of treatment with MRX-2843 and/or GSK269962A will be determined using 3-dimensional biomimicry cultures derived from a panel of AML patient samples, which recapitulate many features of the normal bone marrow niche, including protection from chemotherapy, and provide a robust platform for therapeutic testing. Together these experiments will assess the utility of ROCK1/2 and MERTK/FLT3 inhibitor combination therapies for treatment of AML, provide important information about the efficacy and toxicity of the combination therapy in preclinical mouse models, and may lead to development of a powerful approach to treat AML more effectively and with less toxicity by 1) disrupting the protective interactions between bone marrow stromal cells and leukemic blasts and 2) inhibiting specific molecular targets to induce leukemia cell death.

项目概要/摘要 急性髓系白血病 (AML) 的治疗已有所改善，但成人五年生存率仍低于 60% 和儿科患者。目前的疗法毒性很大，会导致长期副作用，并且经常 老年患者禁用。我们的目标是开发一种具有更好疗效的分子靶向治疗 AML 功效和降低毒性。 MERTK 酪氨酸激酶在 >90% 的儿童和成人中异位表达 AML 患者样本。 MRX-2843 是一种新型小分子，可抑制 MERTK 和 FLT3（已知的 AML 的治疗靶点。 MRX-2843在临床前模型中具有强劲的活性，目前处于I期临床 试验；然而，分子靶向单一疗法的实用性受到了药物开发的限制。 反抗。因此，我们试图找出与 MRX-2843 协同抑制白血病的信号通路 细胞扩张。使用激酶抑制剂库筛选，我们发现 MRX-2843 之间存在协同相互作用 RKI-1447，一种 rho 相关蛋白激酶（ROCK1 和 ROCK2）抑制剂。 ROCK1下调 降低白细胞对保护性骨髓生态位中趋化因子的亲和力，ROCK 抑制会降低 在患者样本培养物中扩增 AML 母细胞，诱导 AML 细胞死亡，并延长小鼠的生存期 反洗钱模型。 MRX-2843/RKI-1447 联合疗法可协同减少体外 AML 细胞增殖 这些效应与细胞周期进程的变化和细胞凋亡的诱导相关。初步数据 还表明 ROCK1/2 抑制可以促进骨髓中 AML 对 MRX-2843 的敏感性。我们 假设同时抑制 ROCK1/2 和 MERTK/FLT3 将减轻疾病负担 单独或与标准 AML 诱导化疗联合治疗，可延长小鼠 AML 的生存期 模型。为了验证这一想法，MRX-2843、GSK269962A 和/或化疗的治疗效果将是 在具有人类 AML 细胞系和/或患者来源的异种移植物的小鼠中测定。确定目标 对于治疗协同作用很重要，shRNA 表达细胞系衍生物（shMERTK、shROCK1、shROCK2、 shCONTROL）将与 MRX-2843、GSK269962A 或车辆结合在异种移植模型中进行测试。到 进一步评估联合疗法针对骨髓疾病的能力、治疗效果 MRX-2843 和/或 GSK269962A 将使用来自以下来源的 3 维仿生培养物进行测定 一组 AML 患者样本，概括了正常骨髓生态位的许多特征，包括 防止化疗，并为治疗测试提供强大的平台。一起这些 实验将评估 ROCK1/2 和 MERTK/FLT3 抑制剂联合疗法的治疗效用 AML，提供有关临床前联合治疗的功效和毒性的重要信息 小鼠模型，并可能导致开发一种更有效地治疗 AML 的强大方法 通过以下方式降低毒性：1) 破坏骨髓基质细胞和白血病母细胞之间的保护性相互作用 2）抑制特定分子靶标以诱导白血病细胞死亡。