Targeted Inhibition in Leukemia

白血病的靶向抑制

• 批准号: 9914382
• 负责人: Jose A Cancelas
• 金额: $ 50.25万
• 依托单位: CINCINNATI CHILDRENS HOSP MED CTR
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-08 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9914382
• 关键词: Acute Myelocytic Leukemia; Adult; Allosteric Site; Apoptosis; Applications Grants; B-Cell Acute Lymphoblastic Leukemia; B-cell precursor acute lymphoblastic leukemia cell; Binding; Binding Sites; Biochemical Genetics; Biological Markers; Biophysics; Breast; Cancer Model; Cell Death; Cells; Cessation of life; Childhood; Childhood Acute Lymphocytic Leukemia; Childhood Acute Myeloid Leukemia; Clinic; Data; Development; Disease; Dose; Drug Binding Site; Drug Kinetics; Drug Targeting; Exhibits; Genes; Genetic; Glioblastoma; Goals; Growth; Guanine; Guanine Nucleotide Exchange Factors; Hematopoiesis; Human; Immunophenotyping; Immunotherapy; In Vitro; Intervention; Leukemia Acute Lymphoblastic Chemotherapy; Leukemic Cell; MAP Kinase Gene; Malignant Neoplasms; Malignant neoplasm of lung; Malignant neoplasm of prostate; Mediator of activation protein; Metallothionein; Methodology; Modeling; Molecular; Molecular Conformation; Molecular Target; Monomeric GTP-Binding Proteins; Neoplasms; Oncogenes; Oncogenic; Oncology; Pathway interactions; Patients; Ph+ ALL; Pharmaceutical Preparations; Pharmacodynamics; Phase I Clinical Trials; Philadelphia; Property; Proteins; Proto-Oncogene Proteins c-abl; Public Health; Relapse; Research; Resistance; Role; Salvage Therapy; Signal Pathway; Signal Transduction; Site; Site-Directed Mutagenesis; Small GTPase Activators; Solid Neoplasm; Structure; Testing; Therapeutic; Toxic effect; Translating; Transplantation; Treatment Efficacy; Tyrosine Kinase Inhibitor; Xenograft procedure; addiction; analog; base; bcr-abl Fusion Proteins; cancer stem cell; chemical group; chemotherapy; combinatorial; cytotoxic; drug efficacy; genetic approach; human disease; human model; in vitro Assay; in vivo; inhibitor/antagonist; leukemia; leukemic stem cell; malignant breast neoplasm; malignant stomach neoplasm; mouse model; non-oncogenic; novel; novel therapeutics; outcome forecast; overexpression; preclinical safety; prevent; repository; small molecule; small molecule inhibitor; stem; stem cells; tumor

ABSTRACT We have identified the first in vivo and in vitro small molecule inhibitor of Vav3, a signaling hub that is overex- pressed in many cancers and an activator of the small GTPase Rac. Rac is a major mediator of oncogenic and non-oncogenic addiction in cancer stem/progenitor cells. At low dose, our inhibitor eliminates TKI-resistance in vivo, prolongs the survival of a mouse model of pre-B-ALL, and eradicates cancer stem cell propagation in a model of mouse serial transplantation. It induces apoptosis of primary pediatric Philadelphia-positive (Ph+) and Ph-like B-ALL and chemotherapy-resistant RAM immunophenotype primary pediatric AML cells. It specifically targets leukemic cells while sparing normal hematopoiesis in vivo and shows no toxicity. In addition, it is active in oncogenic Ras xenografts mouse models of human solid tumors. Given this broad activity and the wide in- volvement of Vav3 and Rac in human disease, it is likely that our inhibitor will be efficacious in several human cancers resistant to current therapies. Even though we focus on Ph+ B-cell acute lymphoblastic leukemia (Ph+ B-ALL) as a simpler cancer model to validate the mechanism of action of our inhibitor, we will test its efficacy in models of pediatric TKI-resistant B- ALL and AML. Despite the introduction of ABL tyrosine kinase inhibitor (TKI) therapy and more recently highly- toxic immunotherapies, Ph+ B-ALL and AML remain poor prognosis diseases, especially in adults, as a result of frequent relapse and resistance to current therapies. The long-term goal of this grant application is a multidrug approach consisting of a TKI and our drug or an optimized derivative as a new therapy for ALL and AML without the toxicity associated with current salvage therapy approaches. We postulate that multitarget approaches in ALL and AML are necessary to prevent resistance to single-agent TKI therapy. Based on our preliminary data, we hypothesize that our drug increases death of leukemia initiating and propa- gating cells and overcomes TKI-resistance by targeting Vav3. The goal of the proposed research is to (1) validate the Vav3/Rac signaling axis as our drug’s target using biochemical and genetic approaches and determine in vivo implications; (2) to identify our drug’s binding site on Vav3 using biophysical, structural, and genetic ap- proaches, and validate the site using site-directed mutagenesis. Finally, (3) we will take advantage of the CCHMC Oncology Leukemia/Solid Tumor Repository to test our drug’s efficacy in PDX models of chemotherapy- resistant pediatric ALL and AML alone and in combination with existing TKI approaches and validate metallothi- onein as a biomarker. If successful, we would like to see our drug, or a more potent analog, move into pre-clinical safety analysis and potentially into a Phase I clinical trial in ALL and AML resistant to TKI therapies. Allosteric targeting of the Vav3 autoinhibited conformation as proposed here could be generalized to other ‘undruggable’ protein-protein interfaces.!

抽象的 我们已经鉴定出第一个体内和体外的 Vav3 小分子抑制剂，Vav3 是一种信号中枢， Rac 在许多癌症中发挥作用，是小 GTP 酶 Rac 的激活剂，是致癌和致癌的主要介质。 低剂量时，我们的抑制剂消除了癌症干细胞/祖细胞中的非致癌成瘾性。 体内，延长前 B-ALL 小鼠模型的存活时间，并根除癌症干细胞在体内的繁殖 它诱导原代儿童费城阳性（Ph+）和小鼠细胞凋亡。 Ph 样 B-ALL 和化疗耐药 RAM 免疫表型原代儿童 AML 细胞。 靶向白血病细胞，同时不影响体内正常造血功能，并且没有毒性。此外，它具有活性。 鉴于这种广泛的活性和广泛的应用，在人类实体瘤的致癌 Ras 异种移植小鼠模型中。 鉴于 Vav3 和 Rac 在人类疾病中的作用，我们的抑制剂很可能对多种人类有效 对当前疗法有抵抗力的癌症。 尽管我们关注 Ph+ B 细胞急性淋巴细胞白血病 (Ph+ B-ALL) 作为一种更简单的癌症模型 为了验证我们的抑制剂的作用机制，我们将在儿科 TKI 耐药 B-模型中测试其功效 尽管引入了 ABL 酪氨酸激酶抑制剂 (TKI) 疗法以及最近的高度- 毒性免疫疗法、Ph+ B-ALL 和 AML 仍然是预后不良的疾病，特别是在成人中，因为 频繁复发和对当前疗法的耐药性本次拨款申请的长期目标是多药治疗。 由 TKI 和我们的药物或优化衍生物组成的方法作为 ALL 和 AML 的新疗法，无需 我们假设与当前挽救治疗方法相关的毒性。 ALL 和 AML 对于防止单药 TKI 治疗产生耐药性是必要的。 根据我们的初步数据，我们发现我们的药物会增加白血病起始和传播的死亡率 通过靶向 Vav3 来门控细胞并克服 TKI 耐药性 本研究的目标是 (1) 验证。 使用生化和遗传学方法将 Vav3/Rac 信号轴作为我们药物的靶标，并确定 (2) 使用生物物理、结构和遗传应用来识别我们的药物在 Vav3 上的结合位点 最后，（3）我们将利用 CCHMC 肿瘤学白血病/实体瘤存储库用于测试我们的药物在化疗 PDX 模型中的疗效 - 单独使用耐药儿童 ALL 和 AML 以及与现有 TKI 方法相结合，并验证金属硫 如果成功，我们希望看到我们的药物或更有效的类似物进入临床前阶段。 安全性分析，并可能进入对 TKI 疗法耐药的 ALL 和 AML 的 I 期临床试验。 这里提出的针对 Vav3 自抑制构象的靶向可以推广到其他“不可成药”的构象 蛋白质-蛋白质界面。！