Validating Syk as a Target for AML Therapy

验证 Syk 作为 AML 治疗靶点

• 批准号: 8296670
• 负责人: Kimberly Stegmaier
• 金额: $ 35.22万
• 依托单位: DANA-FARBER CANCER INST
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-07 至 2014-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8296670
• 关键词: 3' Untranslated Regions; AML1-ETO fusion protein; Acute Myelocytic Leukemia; Acute Promyelocytic Leukemia; Address; Apoptosis; Autoimmune Diseases; B cell differentiation; B-Cell Lymphomas; Biochemical; Biochemical Genetics; Biological; Biological Assay; Blast Cell; Bone Marrow; Cell Death; Cell Line; Cell Survival; Cell surface; Cells; Cessation of life; Chemotherapy-Oncologic Procedure; Clinical; Clinical Trials; Complementary DNA; Complex; Cytotoxic Chemotherapy; Data; Defect; Development; Differentiation Inducer; Disease; Dose; Dysmyelopoietic Syndromes; Epidermal Growth Factor; Epidermal Growth Factor Receptor; Flow Cytometry; Gefitinib; Gene Expression; Gene Expression Profile; Genetic; Genomics; Goals; Grant; Hematologic Neoplasms; Hematopoietic; Human; In Vitro; Laboratories; Lead; Literature; Lymphoma; MAP Kinase Gene; Measurement; Measures; Modeling; Mutagenesis; Myelogenous; Myeloid Cells; PI3K/AKT; Pathogenesis; Pathology; Pathway interactions; Patients; Peripheral; Pharmaceutical Preparations; Pharmacodynamics; Pharmacologic Substance; Phase; Phenotype; Phosphorylation; Phosphotransferases; Pilot Projects; Positioning Attribute; Preclinical Testing; Prodrugs; Protein Tyrosine Kinase; Proteins; Proteomics; RNA Interference; Receptor Signaling; Receptors, Antigen, B-Cell; Refractory; Relapse; Reporting; STAT5A gene; Screening procedure; Signal Transduction; Site; Spleen; Staging; T-Cell Lymphoma; Testing; Therapeutic; Time; Translations; Tretinoin; Tyrosine Kinase Inhibitor; Weight; Work; Xenograft procedure; base; cell growth; genome-wide; high throughput screening; human SYK protein; in vivo; in vivo Model; inhibitor/antagonist; mutant; preclinical study; research study; small hairpin RNA; small molecule; tool; transcription factor

PROJECT ABSTRACT Little progress has been made in the treatment of acute myeloid leukemia (AML) despite dose intensification of cytotoxic chemotherapy. An alternative approach to treating AML is the incorporation of pro-differentiation agents into standard chemotherapy regimens. In order to identify new AML differentiation agents, our laboratory developed a gene expression-based approach to small molecule screening. We identified gefitinib, an epidermal growth factor (EGFR) inhibitor, as an inducer of AML differentiation. EGFR is not expressed in the tested AML cell lines, thus precluding inhibition of this kinase as the mechanism of AML differentiation. Because multiple EGFR inhibitors induce the phenotype, we hypothesize that a shared off-target kinase is the target in AML differentiation. In order to identify candidate gefitinib targets of AML differentiation, we utilized proteomic and genetic approaches. Spleen tyrosine kinase (Syk) was identified as the top candidate. Syk is a nonreceptor tyrosine kinase, important in normal B-cell differentiation, and implicated in hematological malignancies. We hypothesize that Syk is a target for AML therapy and that loss of Syk will result in differentiation and/or cell death in AML. We confirmed with both pharmacological inhibition (R406) and genetic loss of Syk the induction of differentiation and/or death in a pilot study of AML cells. We now propose to more broadly test this hypothesis with the following Specific Aims. Specific Aim 1. Characterize the in vitro and in vivo effects of R406 in AML Specific Aim 2. Establish that Syk is the target of R406 activity in AML Specific Aim 3. Determine the downstream effectors of Syk in AML In Aim 1, we will determine the broad potential of Syk inhibition as an anti-AML therapy. We will measure the in vitro effects of a Syk inhibitor (R406) in a large panel of AML cells on differentiation, cell growth, and apoptosis. We will then extend testing to in vivo studies using primary human AML orthotopic models. Next, in Aim 2, we will confirm that Syk is the target of R406 activity with three parallel approaches: A PCR mutagenesis screen for Syk mutants that rescue the effects of R406 anti-AML activity; a genetic approach using RNA interference, and a pharmacological approach evaluating other small molecule inhibitors of Syk. In Aim 3, we will determine which proteins are critical downstream effectors of Syk signaling in AML using complementary approaches: biochemical, genetic, genomic, pharmacological, and proteomic. The Rigel Pharmaceutical compound, R788, the prodrug of R406, is already in Phase II testing and was recently demonstrated to have activity in autoimmune disease and lymphoma. With Phase I testing now complete and efficacy demonstrated for these diseases, we would be well positioned to rapidly bring R788 to clinical trial. These studies, within the five year time frame of this grant, will have immediate translational relevance and inform the development of a clinical trial testing Syk inhibition in patients with relapsed/refractory AML.

项目摘要 尽管剂量加剧了 细胞毒性化疗。治疗AML的另一种方法是促进分化的纳 标准化疗方案的药物。为了确定新的AML差异化代理，我们的 实验室开发了一种基于基因表达的小分子筛选方法。我们确定了吉非替尼， 表皮生长因子（EGFR）抑制剂，作为AML分化的诱导剂。 EGFR未在 测试的AML细胞系，因此排除了该激酶作为AML分化机制的抑制作用。 因为多个EGFR抑制剂诱导表型，所以我们假设共享的脱靶激酶是 AML分化目标。为了识别候选吉非替尼的AML分化目标，我们使用了 蛋白质组学和遗传方法。脾酪氨酸激酶（SYK）被确定为顶级候选人。 Syk是一个 非受体酪氨酸激酶，在正常B细胞​​分化中很重要，与血液学有关 恶性肿瘤。我们假设SYK是AML治疗的靶标，SYK的丢失将导致 AML的分化和/或细胞死亡。我们确认了药理抑制（R406）和遗传 SYK的丧失在AML细胞的试点研究中，分化和/或死亡的诱导。我们现在建议更多 通过以下特定目标广泛检验该假设。 特定目的1。表征AML中R406的体外和体内效应 具体目标2。确定SYK是AML中R406活性的目标 特定目标3。确定AML中SYK的下游效应子 在AIM 1中，我们将确定SYK抑制作用作为抗AML疗法的广泛潜力。我们将测量 SYK抑制剂（R406）在大型AML细胞中对分化，细胞生长和凋亡的体外作用。 然后，我们将使用原代人AML原位模型将测试扩展到体内研究。接下来，在AIM 2中，我们 将确认SYK是R406活性的靶标，采用三种平行方法：PCR诱变筛选 对于挽救R406抗AML活性影响的SYK突变体；使用RNA干扰的遗传方法 以及评估SYK其他小分子抑制剂的药理方法。在AIM 3中，我们将确定 哪种蛋白质是使用互补方法在AML中SYK信号传导的关键下游效应子： 生化，遗传，基因组，药理和蛋白质组学。 Rigel Pharmaceutical Compound，R788， R406的前药已经在II期测试中，最近被证明具有活性 自身免疫性疾病和淋巴瘤。随着第一阶段测试，现在已经完成了功效 疾病，我们将很适合将R788迅速带入临床试验。这些研究，五个 这笔赠款的年度时间表将具有立即的翻译相关性，并告知开发 复发/难治性AML患者的临床试验测试SYK抑制。