Development of novel anti-leukemia agents targeting the menin-MLL interaction

开发针对 menin-MLL 相互作用的新型抗白血病药物

基本信息

批准号：
8155109
负责人：
Jolanta Grembecka
金额：
$ 32.27万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-09-01 至 2016-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8155109
关键词：
Acute Myelocytic Leukemia Acute leukemia Adult Adverse effects Affect Apoptosis Binding Biochemical Blood Cells Bone Marrow Cells Cells Cellular Assay Characteristics Child Chimeric Proteins Chromosomal translocation Clinical Trials DNA Sequence Rearrangement Data Development Dominant-Negative Mutation Drug Kinetics Generations Genes Goals Growth Hematopoiesis Human Inhibitory Concentration 50 Laboratories Lead Lymphoblastic Leukemia MEN1 gene MLL gene Maximum Tolerated Dose Mediating Menin Metabolic Methods Molecular Target Mus Mutagenesis N-terminal Oncogene Proteins Oncogenic Outcome Patients Peptides Pharmaceutical Chemistry Pharmaceutical Preparations Property Proteins Proto-Oncogenes Reporting Research Specificity Structure-Activity Relationship Survival Rate Testing Therapeutic Agents Therapeutic Intervention Toxic effect analog base cell growth cofactor design drug candidate drug discovery high throughput screening improved in vivo inhibitor/antagonist innovation leukemia leukemogenesis mouse model multidisciplinary novel novel therapeutic intervention novel therapeutics outcome forecast pre-clinical scaffold small molecule

项目摘要

DESCRIPTION (provided by applicant): Chromosomal translocations that affect the proto-oncogene MLL (Mixed Lineage Leukemia) occur in aggressive human acute leukemias, both in children and adults. Fusion of MLL to one of more than 60 partner genes results in generation of the MLL fusion oncoprotein which upregulates expression of Hox genes required for normal hematopoiesis, and ultimately leads to the development of leukemia. Patients harboring fusion of the MLL gene suffer from very aggressive leukemias and respond poorly to available therapies, with only ~35% five-year survival rate, emphasizing that novel therapeutic treatments are urgently needed. All oncogenic MLL fusion proteins have a preserved N-terminal fragment of MLL that interacts with menin, a protein encoded by MEN1 (Multiple Endocrine Neoplasia 1) gene. Importantly, the interaction of menin with the MLL fusion proteins is critical to the leukemogenic activity of the MLL fusions. Therefore, menin functions as an essential oncogenic cofactor in MLL leukemias, and represents a valuable molecular target for therapeutic intervention. We hypothesize that direct targeting of the interaction between menin and MLL fusion proteins with small molecules will reverse the oncogenic potential of MLL fusions and will inhibit the development of leukemia. By applying two independent high throughput screens, we identified over 20 small molecules which specifically bind to menin and inhibit the menin-MLL interaction. These compounds, which belong to several distinct chemotypes, represent the first small molecule inhibitors targeting this interaction. Applying a combination of biochemical, biophysical and cellular assays we were able to evaluate their potency, specificity, and mechanism of action. The most potent compounds competitively displace the MLL-derived peptide from menin with the IC50 values at low micromolar range, with the most potent MI-1 and MI-2 representing two different scaffolds. These compounds selectively inhibit the growth of leukemia cells with MLL translocations, and induce apoptosis and differentiation of MLL leukemia cells. We have tested analogues of MI-1 and MI-2 to establish an initial structure-activity relationship and improve their potency. The most potent analogue of MI-1 synthesized in our laboratory has IC50 = 430 nM for inhibition of the menin-MLL interaction. This compound selectively inhibits the cell growth, induces apoptosis and differentiation of MLL leukemia cells, substantially downregulates expression of Hoxa9 and Meis1 genes, and inhibits transformation by MLL fusion oncoprotein, demonstrating a highly specific mode of action. In this project we propose to further optimize these lead compounds by combining medicinal chemistry, NMR, biochemical and biophysical methods. Compounds will be tested for their activity in leukemia cells and on normal bone marrow cells to validate their mechanism of action and exclude compounds which might cause toxicity issues. In vivo efficacy studies in mouse models of MLL leukemia will also be pursued for selected compounds. If successful, our studies will result in compounds which may provide a novel therapeutic approach for the treatment of leukemias with MLL translocations. PUBLIC HEALTH RELEVANCE: We are proposing to develop small molecules that may reverse the oncogenic function of MLL fusion proteins in acute leukemias. Ultimately, such compounds could be used as highly specific drugs for treatment of patients with aggressive forms of leukemia, which poorly respond to current therapies.

描述（由申请人提供）：在儿童和成人中，影响原始癌基因MLL（混合谱系白血病）的染色体易位（混合谱系白血病）发生在侵略性的人类急性白血病中。 MLL与60多种伴侣基因之一的融合导致MLL融合癌蛋白的产生，该蛋白上调正常造血所需的HOX基因的表达，并最终导致白血病的发展。具有MLL基因融合的患者患有非常侵略性的白血病，对可用疗法的反应较差，仅约35％的五年生存率强调了新型治疗疗法。所有致癌的MLL融合蛋白具有MLL的保留的N末端片段，该蛋白与Menin相互作用，Menin是由Men1（多个内分泌肿瘤1）基因编码的蛋白。重要的是，Menin与MLL融合蛋白的相互作用对于MLL融合的白血病活性至关重要。因此，Menin充当MLL白血病中必不可少的致癌辅助因子，代表了治疗干预的有价值的分子靶标。我们假设直接靶向Menin和MLL融合蛋白与小分子之间的相互作用将逆转MLL融合的致癌潜力，并会抑制白血病的发展。通过应用两个独立的高吞吐量屏幕，我们确定了20多个小分子，这些小分子特异性结合了梅宁并抑制了menin-mll相互作用。这些化合物属于几种不同的化学型，代表了针对这种相互作用的第一个小分子抑制剂。采用生化，生物物理和细胞测定法的结合，我们能够评估其效力，特异性和作用机理。最有效的化合物在低微摩尔范围内具有IC50值的MENIN的MLL衍生肽的竞争能力取代，其中最有效的MI-1和MI-2代表两个不同的支架。这些化合物选择性地抑制了通过MLL易位的白血病细胞的生长，并诱导MLL白血病细胞的凋亡和分化。我们已经测试了MI-1和MI-2的类似物，以建立初始的结构活性关系并提高其效力。在我们的实验室中合成的MI-1最有效的类似物具有IC50 = 430 nm，以抑制Menin-MLL相互作用。这种化合物选择性地抑制细胞的生长，诱导MLL白血病细胞的细胞凋亡和分化，基本下调HOXA9和MEIS1基因的表达，并通过MLL融合癌蛋白抑制转化，表现出高度特异性的作用方式。在这个项目中，我们建议通过结合药物化学，NMR，生化和生物物理方法来进一步优化这些铅化合物。将对它们在白血病细胞和正常骨髓细胞中的活性进行测试，以验证其作用机理并排除可能引起毒性问题的化合物。在选定的化合物中，还将追求在MLL白血病小鼠模型中的体内功效研究。如果成功的话，我们的研究将导致化合物，可能会提供一种新型的治疗方法，用于治疗MLL易位的白血病。公共卫生相关性：我们建议开发小分子，以扭转MLL融合蛋白在急性白血病中的致癌功能。最终，这种化合物可以用作高度特异性的药物，用于治疗具有侵略性白血病的患者，对当前疗法的反应不佳。