Novel Compounds to Inactivate Oncogenic Fusion Proteins

灭活致癌融合蛋白的新型化合物

• 批准号: 8206770
• 负责人: JEFFREY A TORETSKY
• 金额: $ 30.9万
• 依托单位: GEORGETOWN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-01 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8206770
• 关键词: 3-Dimensional; Address; Adolescent; Adverse effects; Amino Acids; Apoptosis; Binding; Biochemical; Biochemistry; Biological Assay; Bone Marrow Transplantation; Bone Tissue; Cancer Patient; Carcinoma; Cell Death; Cell Line; Cells; Cellular biology; Characteristics; Child; Chimeric Proteins; Chromosomal translocation; Clinic; Clinical; Complex; Developmental Therapeutics Program; Disease; Disease-Free Survival; Dose; Drug Design; EWS-FLI1 fusion protein; Ewings sarcoma; FLI1 gene; Family; Family member; Future; Gene Expression; Genetic Transcription; Gold; Growth; Health; Investigation; Knowledge; Lead; Libraries; Malignant Bone Neoplasm; Malignant Neoplasms; Malignant neoplasm of prostate; Metastatic Ewing' s Sarcoma; Molecular Biology; Molecular Profiling; Molecular Target; Morbidity - disease rate; Non-Malignant; Oncogenes; Oncogenic; Patients; Peptides; Pharmaceutical Chemistry; Pharmaceutical Preparations; Property; Proteins; RNA helicase A; Reagent; Recurrent disease; Regimen; Reporter; Research; Resistance; Screening procedure; Series; Specificity; Structure; Targeted Fusion Protein Therapy; Testing; Therapeutic Agents; Toxic effect; Transcription Coactivator; Work; Xenograft Model; Xenograft procedure; base; beta pleated sheet; bone; cDNA Arrays; cell growth; cell motility; chemotherapy; chromatin immunoprecipitation; design; drug discovery; improved; inhibitor/antagonist; killings; leukemia; malignant phenotype; mathematical model; mortality; neoplastic cell; novel; novel therapeutic intervention; novel therapeutics; outcome forecast; peptide A; prevent; protein function; protein protein interaction; research study; response; sarcoma; small molecule; soft tissue; success; transcription factor; tumor; tumor growth; young adult

DESCRIPTION (provided by applicant): Chemotherapy-resistant leukemias and sarcomas contain tumor-specific chromosomal translocations that encode fusion-proteins and these fusion-proteins are expressed only in the tumor. A fusion-protein provides significant tumor target specificity and increases the likelihood that novel therapies targeting the fusion-protein will be both effective and lack non-specific toxicity. Many of the tumor-specific fusion-proteins that function as transcription factors are disordered proteins. Disordered proteins lack the rigid alpha-helical or beta sheet structures required for structure-based drug design. While disordered proteins require a more empiric approach to the discovery of small molecule protein-protein interaction inhibitors, the biochemical properties of disordered proteins may actually favor the success of protein-protein interaction inhibitors. We will develop a novel paradigm to inhibit the protein-protein interaction of an oncogenic fusion protein. The Ewing's Sarcoma Family of Tumors (ESFT) contains a characteristic translocation, t(11:22), which leads to the oncogenic, fusion-protein, transcription factor EWS-FLI1. Therapies that inactivate EWS-FLI1 might address the significant problem of recurrent disease for patients. Since EWS-FLI1 lacks intrinsic enzymatic activity, and is a disordered protein, we will create novel protein-protein interaction inhibitors to block EWS-FLI1 binding to critical protein partners. We identified RNA Helicase A (RHA, p150), a DEAD/H family member that modulates gene expression, as a critical partner of EWS-FLI1. EWS-FLI1 binds to a unique region of RHA that is NOT involved in non-malignant RHA transcriptional modulation. A peptide mimic of this binding region inhibits EWS- FLI1 binding to RHA and we have discovered a lead compound, NSC635437, which has significant structural homology with the peptide mimic. A derivative small molecule of NSC635437, YK-4-279, blocks RHA binding to EWS-FLI1 and induces apoptosis in ESFT cells. We hypothesize that the interaction of RHA with EWS- FLI1 results in a potent transcriptional activator/coactivator complex, which amplifies the functions of both proteins and drives the malignant phenotype of ESFT. Our approach will develop reagents that prevent the binding of EWS-FLI1 to RHA, both to address our hypothesis and create a new therapeutic agent. We will accomplish our objectives by examining the effects of blocking RHA from enhancing EWS-FLI1 function, first using a peptide and then with small molecule protein-protein interaction inhibitors. We will work together with Dr. Milton Brown, a highly regarded medicinal chemist, to chemically optimize our lead compound. Our work has broad applicability to a larger group of tumors, serving as a new paradigm for developmental therapeutics. This paradigm to create small molecule inhibitors of EWS-FLI1 could be used for other translocation-defined malignancies such as chemotherapy-resistant carcinomas, sarcomas and leukemias. Therefore, future work would have a strong potential for a positive impact upon many patients with difficult to treat tumors leading to reduced mortality and morbidity. PUBLIC HEALTH RELEVANCE:New targeted therapies are needed for cancer patients that improve survival and decrease side-effects of therapy. Ewing's Sarcoma Family of Tumors (ESFT) are highly malignant tumors of bone and soft tissue that occur in children, adolescents, and young adults. The tumors often grow in close proximity to bone, but can occur as a soft-tissue mass. Current standard therapy for ESFT patients is a five-drug regimen that lasts for approximately 9 months. Patients who present with localized ESFT have approximately 70% disease-free survival. Patients who present with metastatic ESFT have a poor prognosis (20% disease-free survival) despite intensive therapy. These clinical response rates have persisted for the past decade, even after dose-intensifying chemotherapy and bone marrow transplantation. Therefore, we need to discover novel therapeutic approaches to both reduce treatment related morbidity and improve overall survival. Fortunately, ESFT contain an ideal molecular target. Unfortunately, despite knowledge that inactivation of this ideal target causes ESFT cell death, strategies to inactivate the molecular target have not been brought to the clinic. This project will specifically address the need for new targeted therapies for ESFT and a large number of related malignancies that have chromosomal translocations.

描述（由申请人提供）：化疗耐药性白血病和肉瘤含有编码融合蛋白的肿瘤特异性染色体易位，并且这些融合蛋白仅在肿瘤中表达。融合蛋白提供了显着的肿瘤靶标特异性，并增加了靶向融合蛋白的新疗法既有效又缺乏非特异性毒性的可能性。许多充当转录因子的肿瘤特异性融合蛋白是无序蛋白。无序蛋白质缺乏基于结构的药物设计所需的刚性α螺旋或β折叠结构。虽然无序蛋白质需要更经验性的方法来发现小分子蛋白质-蛋白质相互作用抑制剂，但无序蛋白质的生化特性实际上可能有利于蛋白质-蛋白质相互作用抑制剂的成功。我们将开发一种新的范例来抑制致癌融合蛋白的蛋白质-蛋白质相互作用。尤文氏肉瘤肿瘤家族 (ESFT) 包含一个特征性易位 t(11:22)，它会产生致癌的融合蛋白转录因子 EWS-FLI1。灭活 EWS-FLI1 的疗法可能会解决患者疾病复发的重大问题。由于 EWS-FLI1 缺乏内在的酶活性，并且是一种无序蛋白质，因此我们将创建新型蛋白质-蛋白质相互作用抑制剂来阻止 EWS-FLI1 与关键蛋白质伴侣的结合。我们确定了 RNA 解旋酶 A (RHA，p150)（一种调节基因表达的 DEAD/H 家族成员）作为 EWS-FLI1 的关键伙伴。 EWS-FLI1 与 RHA 的一个独特区域结合，该区域不参与非恶性 RHA 转录调节。该结合区域的肽模拟物抑制 EWS-FLI1 与 RHA 的结合，我们发现了一种先导化合物 NSC635437，它与肽模拟物具有显着的结构同源性。 NSC635437 的衍生小分子 YK-4-279 可阻断 RHA 与 EWS-FLI1 的结合并诱导 ESFT 细胞凋亡。我们假设 RHA 与 EWS-FLI1 的相互作用产生有效的转录激活剂/共激活剂复合物，该复合物放大了两种蛋白的功能并驱动 ESFT 的恶性表型。我们的方法将开发阻止 EWS-FLI1 与 RHA 结合的试剂，这既是为了解决我们的假设，也是为了创造一种新的治疗剂。我们将通过检查阻断 RHA 增强 EWS-FLI1 功能的效果来实现我们的目标，首先使用肽，然后使用小分子蛋白质-蛋白质相互作用抑制剂。我们将与备受推崇的药物化学家 Milton Brown 博士合作，对我们的先导化合物进行化学优化。我们的工作对更多的肿瘤具有广泛的适用性，成为发育治疗的新范例。这种创建 EWS-FLI1 小分子抑制剂的范例可用于其他易位定义的恶性肿瘤，例如化疗耐药性癌、肉瘤和白血病。因此，未来的工作将对许多难以治疗的肿瘤患者产生积极影响，从而降低死亡率和发病率。公共卫生相关性：癌症患者需要新的靶向疗法来提高生存率并减少治疗的副作用。尤文氏肉瘤家族肿瘤 (ESFT) 是发生于儿童、青少年和年轻人的高度恶性的骨和软组织肿瘤。肿瘤通常生长在靠近骨骼的地方，但也可能以软组织肿块的形式出现。目前 ESFT 患者的标准治疗是五种药物治疗方案，持续约 9 个月。出现局部 ESFT 的患者的无病生存率约为 70%。尽管进行了强化治疗，但患有转移性 ESFT 的患者预后仍很差（无病生存率为 20%）。即使在剂量强化化疗和骨髓移植之后，这些临床反应率在过去十年中仍然持续存在。因此，我们需要发现新的治疗方法来减少治疗相关的发病率并提高总体生存率。幸运的是，ESFT 包含一个理想的分子靶点。不幸的是，尽管知道这个理想靶标的失活会导致 ESFT 细胞死亡，但使分子靶标失活的策略尚未应用于临床。该项目将专门解决 ESFT 和大量染色体易位相关恶性肿瘤对新靶向疗法的需求。