Sonic Hedghog Signaling in Cerebellum Development and Medulloblastoma

小脑发育和髓母细胞瘤中的 Sonic Hedghog 信号传导

• 批准号: 7333566
• 负责人: Susana Parathath
• 金额: $ 5.4万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-12-24 至 2009-12-23
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7333566
• 关键词: Ablation; Adverse effects; Behavioral; Biological Models; Birth; Brain; Breast Cancer Cell; Bromodeoxyuridine; Cell Cycle Progression; Cells; Cerebellum; Childhood Brain Neoplasm; Core Facility; Cytoplasmic Granules; Data; Defect; Development; Equilibrium; Erinaceidae; Failure; Fellowship; Flow Cytometry; Genetic; Genetic Transcription; Goals; Human; IGF1 gene; Impaired cognition; In Vitro; Insulin-Like Growth Factor I; Insulin-Like Growth Factor Receptor; Knockout Mice; Lead; Life; Long-Term Survivors; Maintenance; Mass Spectrum Analysis; Mediating; Memorial Sloan-Kettering Cancer Center; Mentors; Messenger RNA; Modeling; Mus; Mutant Strains Mice; N-myc Proto-Oncogenes; Neuroblastoma; Neurologic; Neurons; Operative Surgical Procedures; Pathway interactions; Patients; Pattern; Phase; Play; Polyribosomes; Production; Proliferating; Proliferation Marker; Proteins; Radiation; Regulation; Retroviridae; Role; Signal Pathway; Signal Transduction; Somatomedins; Source; Structure; Syndrome; Techniques; Testing; Therapeutic; Transcriptional Activation; Transgenic Mice; Translations; Up-Regulation; Week; Work; cancer therapy; cell type; chemotherapy; cyclin D2; in vivo; inhibitor/antagonist; insight; insulin receptor substrate 1 protein; interest; medulloblastoma; migration; neoplastic cell; novel; postnatal; precursor cell; programs; promoter; protein degradation; recombinase; retroviral-mediated; small hairpin RNA; small molecule; transcription factor; tumor

DESCRIPTION (provided by applicant): The cerebellum is a brain structure responsible for integrating and coordinating neurological inputs from several sources in order to maintain equilibrium and balance. It is an interesting brain structure in that it develops after birth. One of the cell types within the cerebellum that is critical for proper postnatal development are cerebellar granule neuron precursors (CGNP). During the first two weeks of life in mice these cells undergo a rapid expansion phase. Failure of CGNPs to exit this high proliferate program has been suggested to lead to medulloblastoma formation, the most common form of pediatric brain tumor. Medulloblastoma is relatively responsive to traditional cancer treatments, including surgery, chemotherapy and radiation. However long-term survivors often suffer from life-long developmental, behavioral, and cognitive disturbances. These devastating side effects underscore the need to understand the basic mechanisms underlying medulloblastoma, so novel treatments can be developed to specifically target tumor cells without damaging the developing brain. The long-term objectives of this project is to identify nodes of cross-talk between Sonic hedgehog and IGF signaling pathways both of which have been implicated in medulloblastoma. Greater understanding of these pathways may lead to the development of small molecule treatments reducing the need for radiation and chemotherapy in these young patients. In order to accomplish this goal we have developed an interdisciplinary proposal incorporating various techniques and models. Our preliminary data indicate that Shh signaling increases IRS1 protein levels, a scafold directly downstream of the IGF receptor, but not IRS1 mRNA in cultured CGNPs. In aim 1 we will test the hypothesis that Shh proliferative signaling in CGNPs positively regulates IGF pathway activity through up-regulation of IRS1 protein. We will look at IRS1 protein turnover as well as polysome analysis including microarray and mass spectrometry analysis. In aim 2 we will use retroviral mediated over-expression of IRS1 and lentivirally-delivered shRNAto determine if IRS1 is necessary/sufficient for Shh mediated CGNP proliferation in culture. In aim 3 we will determine the role of IRS1 in vivo by analyzing CGNP proliferation and cerebella development in mice lacking IRS1 either constitutively or conditionally in the cerebellum. In conjunction with MSKCC Mouse Genetics core facility we will develop mice conditionally lacking IRS1 in the cerebellum. We will analyze the role of CGNP proliferation using in vivo as well as in vitro by culturing CGNPs and treating with Cre to remove IRS1.

描述（由申请人提供）：小脑是负责整合和协调来自多个来源的神经输入以保持平衡和平衡的大脑结构。这是一个有趣的大脑结构，因为它在出生后发育。小脑内对出生后正常发育至关重要的细胞类型之一是小脑颗粒神经元前体（CGNP）。在小鼠生命的前两周，这些细胞经历了一个快速扩增阶段。CGNP未能退出这种高增殖程序已被认为导致髓母细胞瘤形成，这是儿科脑肿瘤的最常见形式。髓母细胞瘤对传统的癌症治疗，包括手术，化疗和放疗相对敏感。然而，长期幸存者往往遭受终身发展，行为和认知障碍。这些毁灭性的副作用强调了了解髓母细胞瘤基本机制的必要性，因此可以开发新的治疗方法来特异性靶向肿瘤细胞，而不会损害发育中的大脑。本项目的长期目标是确定与髓母细胞瘤有关的Sonic hedgehog和IGF信号通路之间的串扰节点。对这些途径的更深入了解可能会导致小分子治疗的发展，从而减少这些年轻患者对放疗和化疗的需求。为了实现这一目标，我们开发了一个跨学科的建议，包括各种技术和模型。我们的初步数据表明，Shh信号增加IRS 1蛋白水平，直接下游的IGF受体的scafold，但不是IRS 1 mRNA在培养的CGNP。在目的1中，我们将检验CGNP中的Shh增殖信号传导通过上调IRS 1蛋白而正调节IGF途径活性的假设。我们将研究IRS 1蛋白质周转以及多核糖体分析，包括微阵列和质谱分析。在目标2中，我们将使用逆转录病毒介导的IRS 1过表达和慢病毒递送的shRNA来确定IRS 1对于培养物中Shh介导的CGNP增殖是否是必需的/足够的。在目标3中，我们将通过分析小脑中组成性或条件性缺乏IRS 1的小鼠的CGNP增殖和小脑发育来确定IRS 1在体内的作用。与MSKCC小鼠遗传学核心设施一起，我们将开发小脑中条件性缺乏IRS 1的小鼠。我们将通过培养CGNP并用Cre处理以去除IRS 1来分析CGNP在体内和体外增殖中的作用。