Disrupting the AF4-AF9 protein complex in MLL leukemias.

破坏 MLL 白血病中的 AF4-AF9 蛋白复合物。

• 批准号: 7350846
• 负责人: Charles Stanley Hemenway
• 金额: $ 12.92万
• 依托单位: LOYOLA UNIVERSITY CHICAGO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-12 至 2010-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7350846
• 关键词: 11q23; 4q21; AF-9 protein; Acute Lymphocytic Leukemia; Acute leukemia; Adult; Amino Acids; Anisotropy; Apoptosis; Binding; Biological Assay; Buffers; C-terminal; Cell Survival; Cells; Chemicals; Child; Chromosomal translocation; Collection; Complex; Condition; Cytotoxic Chemotherapy; Data; Differentiation and Growth; Dimethyl Sulfoxide; Disease; Dissociation; Drug usage; Dyes; Elements; Enzymes; Equilibrium; Fluorescence; Fluorescence Polarization; Goals; Hematopoietic; Hematopoietic stem cells; In Vitro; Label; Lead; MLL gene; MLLT2 gene; MLLT3 gene; Measurement; Measures; Molecular; Molecular Bank; New Agents; Peptide Library; Peptides; Performance; Personal Satisfaction; Pharmaceutical Preparations; Process; Protein Binding; Proteins; Range; Reciprocal Translocation; Recombinants; Refractory; Reproducibility; Research; Resistance; Score; Screening procedure; Series; Signal Transduction; Site; Solutions; Solvents; System; Techniques; Testing; Time; Toxic effect; Treatment outcome; United States National Institutes of Health; Validation; assay development; base; chemotherapy; combinatorial; drug development; high throughput screening; improved; in vivo; inhibitor/antagonist; leukemia; link protein; novel strategies; outcome forecast; pharmacophore; precursor cell; protein protein interaction; small molecule; synthetic peptide; therapeutic target; therapy resistant

DESCRIPTION (provided by applicant): The ultimate goal of this project is to develop promising new agents for the treatment of acute lymphoblastic leukemia (ALL) characterized by a specific t(4;11) chromosome translocation. t(4;11) leukemia is a relatively common subtype of ALL and is unusually resistant to cytotoxic chemotherapy. The isolation, validation, and optimization of new compounds to treat t(4;11) leukemia is important given the limitations of currently available treatments. We have identified a protein:protein interaction that appears to be critical for the survival of t(4;11) leukemia. More important, small peptides that disrupt the interaction of these two proteins, AF4 and AF9, induce programmed cell death in t(4;11) leukemia cells. Additionally, these peptides do not inhibit the growth and differentiation of normal hematopoietic progenitor cells. These data indicate that the AF4-AF9 protein complex is a promising target for drug development. The NIH Molecular Libraries Screening Center Network offers a unique opportunity to screen an extensive molecular library to identify additional compounds that block AF4-AF9 binding. Here, we propose to develop an assay system that is well suited for high throughput screening of inhibitors of AF4-AF9 binding. Fluorescence polarization (FP) is a powerful technique to measure protein binding in a homogeneous solution. The technique is particularly well suited to measuring AF4-AF9 binding as the molecular complex can be mimicked by a peptide "probe" bound to the C-terminal domain of AF9. Furthermore, FP assays can be easily modified to analyze inhibitors of protein binding. FP competition assays have been used successfully for high throughput screening of inhibitors of other protein:protein interactions. Once optimized, the assay is simple, rapid, and inexpensive. In addition to a primary FP screening assay, we describe secondary assays to analyze "hits". These secondary assays include analyses of the anti-leukemic activity of lead compounds and have already been validated. It is anticipated that, following refinement, compounds identified and verified by this screening process will provide useful new anti-leukemic therapies. Despite improvements in the treatment of leukemia, some forms of the disease remain resistant to therapy. Here, we describe a system to rapidly identify chemicals that may serve as new drugs for the treatment of one of the most resistant forms of acute leukemia. We propose to develop and refine this testing system so that it may be used to isolate promising drug candidates from a large collection of chemicals developed by NIH.

描述（由申请人提供）：该项目的最终目标是开发有希望的新药物，用于治疗以特定t（4; 11）染色体易位为特征的急性淋巴细胞白血病（ALL）。 t（4; 11）白血病是所有人的相对常见亚型，并且对细胞毒性化学疗法具有异常抗性。鉴于当前可用的治疗的局限性，对治疗T（4; 11）白血病的新化合物的隔离，验证和优化至关重要。我们已经确定了一种蛋白质：蛋白质相互作用，这对于T（4; 11）白血病的存活至关重要。更重要的是，破坏这两种蛋白AF4和AF9的相互作用的小肽会诱导T（4; 11）白血病细胞中编程的细胞死亡。另外，这些肽不会抑制正常造血祖细胞的生长和分化。这些数据表明AF4-AF9蛋白复合物是药物开发的有希望的靶标。 NIH分子库筛选中心网络提供了一个独特的机会来筛选广泛的分子库，以识别阻断AF4-AF9结合的其他化合物。在这里，我们建议开发一种非常适合对AF4-AF9结合抑制剂的高吞吐量筛选非常适合的测定系统。荧光极化（FP）是一种在均匀溶液中测量蛋白质结合的强大技术。该技术特别适合测量AF4-AF9结合，因为可以通过与AF9的C末端结构域结合的肽“探针”模仿分子复合物。此外，可以轻松地修改FP分析以分析蛋白质结合的抑制剂。 FP竞争测定已成功用于对其他蛋白质相互作用的抑制剂的高通量筛选。一旦优化，该测定方法简单，快速且价格便宜。除了主要的FP筛选测定外，我们还描述了分析“命中”的次要测定。这些次要测定包括对铅化合物抗白血病活性的分析，并且已经得到验证。可以预料，在改进之后，通过此筛查过程确定和验证的化合物将提供有用的新抗白血病疗法。尽管白血病的治疗有所改善，但某些形式的疾病仍然对治疗具有抵抗力。在这里，我们描述了一个系统，可以快速识别可以用作治疗急性白血病之一的新药的化学物质。我们建议开发和完善该测试系统，以便将其用于将有希望的候选药物与NIH开发的大量化学物质分离。