Discovering small molecules that overcome differentiation arrest in acute myeloid

发现克服急性髓系细胞分化停滞的小分子

• 批准号: 8139365
• 负责人: David B Sykes
• 金额: $ 4.43万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8139365
• 关键词: Acute; Acute Myelocytic Leukemia; Acute Promyelocytic Leukemia; Acute leukemia; Address; Adult; Arsenic; Binding; Biological; Biological Assay; Biological Models; Bone Marrow; Cell Line; Cell surface; Cells; Chemicals; Chimeric Proteins; Collaborations; DNA; DNA-Protein Interaction; Development; Differentiation Antigens; Differentiation Therapy; Disease; Engineering; Estrogen Receptors; Estrogens; Fluorescence; Gene Expression; Genes; Green Fluorescent Proteins; Hematopoiesis; Hematopoietic; Homeodomain Proteins; Human; In Vitro; Incubated; Investigation; Leukemic Cell; MLL gene; MLLT3 gene; Maintenance; Mediating; Modeling; Modification; Molecular Probes; Muramidase; Mus; Mutation; Myelogenous; Myeloid Cells; Oncogene Proteins; Patients; Poison; Process; Proteins; Research; Sampling; Screening procedure; Staging; Surface; Survival Rate; Testing; Transgenic Mice; Transgenic Organisms; Tretinoin; United States National Institutes of Health; Wild Type Mouse; chemotherapy; counterscreen; in vitro Model; in vivo; inhibitor/antagonist; insight; intercalation; leukemia; novel; novel strategies; promoter; protein expression; receptor; small molecule; standard of care; success; therapeutic target; therapy development

DESCRIPTION (provided by applicant): Acute myeloid leukemia (AML) in adults is a devastating disease with a 5-year survival rate of only 25%. New treatments for AML are lacking, and the current standard of care for chemotherapy has not changed in the last thirty years. One success story in the treatment of AML has been the development of therapies which promote the maturation, or differentiation of the leukemic cells. In the small subset (~10%) of AML patients with acute promyelocytic leukemia (APL), differentiation therapy in the form of all-trans retinoic acid (ATRA) and arsenic are both well-tolerated and extremely effective, leading to 5-year survival rates approaching 80%. Unfortunately, differentiation therapy is not available for the remaining 90% of acute myeloid leukemia patients. The homeobox protein HoxA9 is expressed in early hematopoiesis and is critical to the normal development of cells along the myeloid lineage. The inappropriate expression of HoxA9 has been demonstrated in approximately 70% of AML. Furthermore, the subset of leukemias which express a fusion oncoprotein involving the MLL (mixed lineage leukemia) gene are dependent upon the expression of HoxA9. These observations make HoxA9 and its downstream targets attractive candidates for inhibition by small molecule probes. Research has been hindered by inadequate model systems of leukemia and the limited availability of primary patient samples. A novel in vitro model of AML has been developed whereby primary murine myeloid cells are arrested in an immature state by the oncoprotein HoxA9. These cells allow for the identification of biologically relevant compounds that can overcome myeloid differentiation arrest. Two types of molecules can be identified: those that directly interfere with the mechanism of differentiation arrest established by HoxA9, and those that are capable of promoting differentiation in a HoxA9-independent manner. The assay cell line is engineered with a built-in marker of differentiation as it expresses the green fluorescent protein (GFP) from a promoter which is active only in mature cells. Thus, compounds that promote differentiation can be readily identified in a high-throughput fashion by assaying cells for green fluorescence. Secondary and counterscreen assays will eliminate potentially autofluorescent compounds and will confirm the effect on myeloid differentiation by assaying for changes in gene expression and cell surface marker expression. The development of a small molecule capable of promoting differentiation in acute myeloid leukemia will be an important advancement in the current state of leukemia chemotherapy. Page 1 of 1 PUBLIC HEALTH RELEVANCE: Acute myeloid leukemia (AML) is a devastating disease and new treatments for AML are in desperate need. Traditional chemotherapy, which typically poisons rapidly dividing leukemia cells, is ultimately ineffective in 75% of cases. A novel model system of AML has been devised to identify novel compounds which trigger leukemic cells to resume the normal process of maturation, thereby losing their proliferative and leukemic potential. Page 1 of 1

描述(申请人提供)：成人急性髓系白血病(AML)是一种毁灭性的疾病，5年存活率仅为25%。AML缺乏新的治疗方法，目前的化疗标准在过去30年里没有改变。AML治疗中的一个成功案例是促进白血病细胞成熟或分化的治疗方法的发展。在AML合并急性早幼粒细胞白血病(APL)的一小部分患者(~10%)中，以全反式维甲酸(ATRA)和砷为代表的分化治疗耐受性良好，且非常有效，导致5年生存率接近80%。不幸的是，分化治疗不适用于其余90%的急性髓系白血病患者。同源盒蛋白HoxA9在早期造血细胞中表达，对髓系细胞的正常发育至关重要。HoxA9在大约70%的AML中有不适当的表达。此外，表达涉及MLL(混合血统白血病)基因的融合癌蛋白的白血病亚群依赖于HoxA9的表达。这些观察结果使HoxA9及其下游靶点成为小分子探针抑制的有吸引力的候选对象。白血病模型系统的不完善和原始患者样本的有限阻碍了研究。建立了一种新的AML体外模型，即原代小鼠髓系细胞被癌蛋白HoxA9阻止在未成熟状态。这些细胞可以鉴定生物学上相关的化合物，这些化合物可以克服髓系分化停滞。可以识别两种类型的分子：一种是直接干扰HoxA9所建立的分化抑制机制的分子，另一种是能够以非HoxA9方式促进分化的分子。该检测细胞系设计了一个内置的分化标记，因为它表达来自启动子的绿色荧光蛋白(GFP)，该启动子只在成熟细胞中活跃。因此，通过分析细胞的绿色荧光，可以很容易地以高通量的方式识别促进分化的化合物。二级和反筛选分析将消除潜在的自体荧光化合物，并将通过分析基因表达和细胞表面标记表达的变化来确认对髓系分化的影响。开发一种能够促进急性髓系白血病分化的小分子将是当前白血病化疗状态下的重要进展。第1页，共1页 公共卫生相关性：急性髓系白血病(AML)是一种毁灭性的疾病，迫切需要新的治疗方法。传统化疗通常会毒化快速分裂的白血病细胞，但在75%的病例中最终无效。设计了一种新的急性髓系白血病模型系统，以鉴定新的化合物，这些化合物可以触发白血病细胞恢复正常的成熟过程，从而失去其增殖和白血病的潜力。第1页，共1页