Novel small-molecule inhibitors of Wee1 kinase for medulloblastoma treatment

用于治疗髓母细胞瘤的新型 Wee1 激酶小分子抑制剂

基本信息

批准号：
8568665
负责人：
Philip Reigan
金额：
$ 23.18万
依托单位：
UNIVERSITY OF COLORADO DENVER
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-07-15 至 2015-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8568665
关键词：
Accounting Adverse effects Aftercare Alkylating Agents Alternative Therapies Binding Biodistribution Biological Assay Blood - brain barrier anatomy Cell Cycle Checkpoint Cell Death Cell Survival Cells Cessation of life Characteristics Chemosensitization Child Childhood Brain Neoplasm Chromatin Structure Cisplatin Clinic Clinical Code Cytotoxic Chemotherapy DNA DNA Damage DNA biosynthesis Data Defect Development Diffuse Docking Dorsal Dose Drug Kinetics Drug or chemical Tissue Distribution Drug resistance Excision Future Gene Expression Genes Genomics Growth Harvest Human In Vitro Lead Libraries Malignant Childhood Neoplasm Malignant neoplasm of brain Mediating Mitosis Mitotic Checkpoint Molecular Molecular Target Mus Neoplasm Metastasis Neurocognitive Operative Surgical Procedures Outcome Pathway Analysis Pathway interactions Patients Penetration Pharmaceutical Preparations Phosphotransferases Plasma Proteins Play Primary Brain Neoplasms Property Protein Kinase Quality of life Radiation Research Resistance Risk Role S Phase Screening Result Series Small Interfering RNA Specificity Structure Survival Rate System Testing Therapeutic Tissues Xenograft Model Xenograft procedure base cell growth chemotherapy clinical efficacy cytotoxic deafness design high risk histone acetyltransferase improved in vitro activity in vivo in vivo Model inhibitor/antagonist kinase inhibitor medulloblastoma medulloblastoma cell line neoplastic cell novel outcome forecast pharmacophore prevent public health relevance resistance mechanism screening small molecule transcription factor treatment duration tumor tumor growth tumor progression

项目摘要

DESCRIPTION (provided by applicant): Medulloblastoma is the most common primary brain tumor in children. Current treatment for medulloblastoma includes surgical resection, radiation and chemotherapy with DNA alkylating agents, such as cisplatin. Although this approach to therapy has improved survival rates, high doses of cytotoxic chemotherapy are required to circumvent drug resistance mechanisms and to confer clinical efficacy, and unfortunately this often results in lasting neurocognitive defects, stunted growth, deafness, and even secondary tumors. The specificity and efficacy of chemotherapy must be improved to safely allow dose reductions and reduce drug-related adverse effects. Furthermore, while current therapy for standard-risk patients has resulted in improved survival rates, there is a subset of high-risk patients with Myc amplification who continue to have an extremely poor prognosis with a 5-year survival rate of less than 30%. Therefore, a more thorough understanding of the molecular pathways in medulloblastoma is critical for the development of more specific novel drugs to improve outcomes in high-risk patients. We identified Wee1 kinase as a potential new molecular target for medulloblastoma from an integrated genomic analysis using pathway analysis of gene expression and a kinome-wide siRNA screen of medulloblastoma cells. The Wee1 kinase participates in the G2-M checkpoint to prevent mitosis in the presence of DNA damage and therefore may play a role in drug resistance to DNA alkylating agents. Our preliminary data indicate that Wee1 prevents DNA damage-induced cell death by cisplatin and that the known Wee1 inhibitor MK1775 displays synergistic activity with cisplatin. However, the selectivity of MK1775 has not been rigorously assessed and it appears to have a high potential for binding to plasma protein and has a reduced capacity to diffuse across the blood brain barrier, restricting its usefulness in the clinic for the treatment of brain cancers. Therefore, a central aim of this research is to determine the structural requirements for small molecule binding to Wee1 to develop novel Wee1 selective inhibitors with improved drug properties and examine the potential of targeting Wee1 in medulloblastoma. We propose to screen the SelleckChem library of 194 kinase inhibitors by computational-based docking and in in vitro activity and binding assays. The data from these screens will be correlated to identify a subset of active compounds which will be used as a basis for inhibitor design. The fact that Wee1 lacks both the HRD and DFG motifs presents the opportunity for selective targeting. We will synthesize a small series of novel inhibitors and test them in parallel with MK1775 in our cell-based systems. We will evaluate the effect of these inhibitors on tumor cell growth as single agents and test if these inhibitors display synergistic activity with cisplatin. In addition, we will determine if p53 playsa role in mediating sensitivity to Wee1 inhibition in medulloblastoma and if Wee1 inhibition has therapeutic potential in tumors that have high Myc amplification which is characteristic of high risk patients. We will then extend our studies into in vivo models to determine the pharmacokinetics and tissue distribution of the Wee1 inhibitors and their effect on tumor growth in our xenograft model.

描述（由申请人提供）：髓母细胞瘤是儿童中最常见的原发性脑肿瘤。目前髓母细胞瘤的治疗包括手术切除、放疗和使用 DNA 烷化剂（例如顺铂）的化疗。尽管这种治疗方法提高了生存率，但需要高剂量的细胞毒性化疗来规避耐药机制并赋予临床疗效，不幸的是，这通常会导致持久的神经认知缺陷、生长发育不良、耳聋，甚至继发性肿瘤。必须提高化疗的特异性和疗效，以安全地减少剂量并减少药物相关的不良反应。此外，虽然目前对标准风险患者的治疗已提高了生存率，但仍有一部分 Myc 扩增的高风险患者的预后仍然极差，5 年生存率低于 30%。因此，更全面地了解髓母细胞瘤的分子途径对于开发更具体的新药以改善高危患者的预后至关重要。我们通过基因表达途径分析和髓母细胞瘤细胞全激酶组 siRNA 筛选的综合基因组分析，确定 Wee1 激酶是髓母细胞瘤的潜在新分子靶点。 Wee1 激酶参与 G2-M 检查点，以防止 DNA 损伤时的有丝分裂，因此可能在 DNA 烷化剂的耐药性中发挥作用。我们的初步数据表明，Wee1 可防止顺铂引起的 DNA 损伤诱导的细胞死亡，并且已知的 Wee1 抑制剂 MK1775 显示出与顺铂的协同活性。然而，MK1775 的选择性尚未经过严格评估，它似乎具有很高的与血浆蛋白结合的潜力，并且扩散穿过血脑屏障的能力较低，限制了其在临床治疗脑癌的用途。因此，本研究的一个中心目标是确定小分子与 Wee1 结合的结构要求，以开发具有改善药物特性的新型 Wee1 选择性抑制剂，并研究靶向 Wee1 在髓母细胞瘤中的潜力。我们建议通过基于计算的对接以及体外活性和结合测定来筛选 194 种激酶抑制剂的 SelleckChem 文库。来自这些筛选的数据将被关联起来以确定活性化合物的子集，其将用作抑制剂设计的基础。 Wee1 缺乏 HRD 和 DFG 基序这一事实为选择性靶向提供了机会。我们将合成一小系列新型抑制剂，并在我们的细胞系统中与 MK1775 并行测试它们。我们将评估这些抑制剂作为单一药物对肿瘤细胞生长的影响，并测试这些抑制剂是否与顺铂表现出协同活性。此外，我们将确定 p53 是否在介导髓母细胞瘤对 Wee1 抑制的敏感性中发挥作用，以及 Wee1 抑制是否对具有高 Myc 扩增（这是高风险患者的特征）的肿瘤具有治疗潜力。然后，我们将研究扩展到体内模型，以确定 Wee1 抑制剂的药代动力学和组织分布及其对异种移植模型中肿瘤生长的影响。