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：
8700556
负责人：
Philip Reigan
金额：
$ 19.12万
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 2016-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8700556
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）：髓母细胞瘤是儿童最常见的原发性脑肿瘤。当前对髓母细胞瘤的治疗包括手术切除，放射和化疗与DNA烷基化剂，例如顺铂。尽管这种治疗方法的存活率提高了，但需要高剂量的细胞毒性化疗来绕过耐药性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，发育不良的生长，耳聋甚至次要肿瘤。必须提高化学疗法的特异性和功效，以安全地减少剂量并减少与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却提高了存活率，但有一部分具有MYC扩增的高危患者，他们的预后较差，5年生存率低于30％。因此，对髓母细胞瘤中分子途径的更透彻了解对于开发更具体的新型药物以改善高危患者的预后至关重要。我们使用基因表达的途径分析和髓母细胞瘤细胞的整个基因组siRNA筛选，将WEE1激酶视为髓母细胞瘤的潜在新分子靶标。 WEE1激酶参与G2-M检查点，以防止在DNA损伤的情况下进行有丝分裂，因此可能在对DNA烷基化剂的耐药性中起作用。我们的初步数据表明，WEE1阻止了顺铂诱导的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。但是，MK1775的选择性尚未进行严格评估，并且它似乎具有与血浆蛋白结合的很高潜力，并且具有降低的能力在跨血脑屏障中扩散，从而限制了其在诊所中治疗脑癌的有用性。因此，这项研究的主要目的是确定与WEE1结合的小分子结构的结构要求，以开发具有改善药物特性的新型WEE1选择性抑制剂，并检查靶向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在体外活性和结合测定中筛选194个激酶抑制剂的Selleckchem库。这些屏幕的数据将相关，以识别活性化合物的子集，该子集将用作抑制剂设计的基础。 WEE1缺乏HRD和DFG图案的事实为选择性定位提供了机会。我们将合成一小部分新型抑制剂，并在基于细胞的系统中与MK1775并行测试。我们将评估这些抑制剂对肿瘤细胞生长的作用作为单一药物，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发挥作用在介导对髓母细胞瘤中WEE1抑制敏感性的敏感性以及WEE1抑制作用中是否具有高风险患者特征的较高MYC扩增的肿瘤中具有治疗潜力。然后，我们将研究将研究扩展到体内模型中，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。