Investigating the Effects of Stem Cell Positional Identity on Brain Tumor Development

研究干细胞位置同一性对脑肿瘤发展的影响

• 批准号: 9256911
• 负责人: Gabrielle Rushing
• 金额: $ 2.87万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-12-01 至 2019-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9256911
• 关键词: Ablation; Acute; Adenoviruses; Adult; Affect; Alleles; Automobile Driving; Benign; Biological; Brain; Brain Neoplasms; Brain region; Cell Culture Techniques; Cell Proliferation; Cell Size; Cells; Childhood; Clinical; Collaborations; Complement; Cultured Cells; Data; Development; Disease; Dorsal; Event; FRAP1 gene; Flow Cytometry; Future; Genes; Goals; Growth; Heterogeneity; Heterotopic Transplantation; Human; Hyperactive behavior; Injectable; Injection of therapeutic agent; Left; Life; Location; Measures; Metabolic; Microscopy; Modeling; Mus; Mutation; Neonatal; Neurodevelopmental Disorder; Neuroepithelial, Perineurial, and Schwann Cell Neoplasm; Nodule; Pathway interactions; Patients; Phosphorylation; Positioning Attribute; Pre-Clinical Model; Predisposition; Property; Proteins; Protocols documentation; Reporter; Research; Research Personnel; SHH gene; Signal Transduction; Sirolimus; Stem cells; Structure; Subependymal; Subependymal Giant Cell Astrocytoma; Subgroup; TSC1 gene; TSC1/2 gene; TSC2 gene; Tamoxifen; Techniques; Testing; Tissues; Translations; Transplantation; Tuberous sclerosis protein complex; Tumor-Derived; Viral; Wild Type Mouse; Work; base; cell growth; cohort; experience; experimental study; high throughput screening; mTOR Inhibitor; mTOR Signaling Pathway; member; mouse model; mutant; nerve stem cell; new therapeutic target; novel; novel therapeutics; postnatal; progenitor; prognostic; protein expression; red fluorescent protein; relating to nervous system; response; stem; stem cell niche; stem cell population; subventricular zone; therapeutic candidate; tool; transcriptomics; tumor

PROJECT SUMMARY The broad, long-term objectives are to understand how heterogeneity within stem cell populations affects disease states and tumor development in the brain. The goal of the proposed project is to investigate how stem/progenitor cells within different regions of the brain can differentially contribute to the formation of brain tumors in Tuberous Sclerosis Complex (TSC). TSC is a disease of hyperactive mTOR pathway activity, resulting in increased cell size, survival and proliferation. TSC patients may develop either of two tumor types within the within the subventricular zone (SVZ), the largest stem cell niche in the adult and pediatric brain. They can develop small benign asymptomatic tumors, called subependymal nodules (SENS) or develop larger potentially life-threatening tumors, termed subependymal giant cell astrocytomas (SEGAs). Clinically, these tumor types are distinguished by size and location, with SEGAs being larger and restricted to the ventral SVZ. Despite clear prognostic differences, the mechanisms driving location-specific, larger tumor development are not well understood. Recent work has determined that the stem and progenitor cells within the SVZ have a positional identity- their location within the niche can predict the type of progeny they create. This property appears to be intrinsic as the cells retain their potential upon transplantation. This new information presents an intriguing possibility that SEGAS, which are thought to form from SVZ stem/progenitor cells, may reflect the properties of their location of origin. Additionally, the location of a stem/progenitor cell may determine its susceptibility to mutations in TSC1/2. The overarching hypothesis is that cell-intrinsic, region-specific differences in stem/progenitor-cell signaling promote the formation of location-specific tumors in the brain. The specific aims of this project are to (1) determine the intrinsic effects of cell location on neural tumor development in Tuberous Sclerosis Complex and (2) dissect the mTOR signaling pathway components that differ between dorsal and ventral neural stem/progenitor cells. To accomplish these aims, we will use a conditional mouse model of TSC in combination with localized Cre activity to test the combination of specific stem/progenitor cell subgroups to larger tumor formation. In tandem with this model, we will use primary stem cell cultures to examine mTOR signaling in wild type and mutant cells using both microscopy and a novel flow- cytometry based approach. To achieve the proposed work, we are incorporating a clinical experience with our collaborator Dr. Kevin Ess, collaboration with a world expert in phospho-specific flow cytometry (Dr. Jonathan Irish) and utilizing our lab’s unique technique of targeting subpopulations within the stem cell niche. The proposed research is highly relevant as it will reveal novel information regarding the origin of TSC brain tumors. Additionally, this work is broadly applicable to many fields as it investigates how stem cells can possess differential basal metabolic programming and potential to signal through growth pathways depending on their location within a stem cell niche.

项目概要 广泛的长期目标是了解干细胞群体内的异质性如何影响 该项目的目标是研究大脑中的疾病状态和肿瘤发展。 大脑不同区域内的干/祖细胞对大脑形成的贡献不同 结节性硬化症 (TSC) 中的肿瘤是一种 mTOR 通路活性过度活跃的疾病。 导致细胞大小增加、生存和增殖，TSC 患者可能会发展成两种肿瘤类型中的任何一种。 脑室下区（SVZ）内是成人和儿童大脑中最大的干细胞生态位。 它们可以发展成小的良性无症状肿瘤，称为室管膜下结节 (SENS) 或发展成更大的肿瘤 临床上，这些肿瘤可能危及生命，称为室管膜下巨细胞星形细胞瘤（SEGA）。 肿瘤类型根据大小和位置来区分，SEGA 较大且仅限于腹侧 SVZ。 尽管预后存在明显差异，但驱动特定位置、更大肿瘤发展的机制是 最近的工作已经确定 SVZ 内的干细胞和祖细胞具有 位置身份——它们在生态位中的位置可以预测它们创造的后代的类型。 这一新信息似乎是内在的，因为细胞在移植后保留了其潜力。 有趣的是，SEGAS被认为是由SVZ干/祖细胞形成，可能反映了 此外，干细胞/祖细胞的位置可能决定其起源位置的特性。 TSC1/2 突变的易感性总体假设是细胞固有的、区域特异性的。 干细胞/祖细胞信号传导的差异促进了大脑中特定位置肿瘤的形成。 该项目的具体目标是（1）确定细胞位置对神经肿瘤的内在影响 结节性硬化症复合体的发展和 (2) 剖析 mTOR 信号通路成分 背侧和腹侧神经干/祖细胞之间存在差异，为了实现这些目标，我们将使用 TSC的条件小鼠模型结合局部Cre活性来测试特定的组合 干细胞/祖细胞亚群到更大的肿瘤形成，我们将使用原代干细胞。 使用显微镜和新型流式细胞培养物检查野生型和突变细胞中的 mTOR 信号传导 为了实现所提出的工作，我们正在将临床经验与我们的方法相结合。 合作者 Kevin Ess 博士，与磷酸特异性流式细胞术的世界专家合作（Jonathan 博士） 爱尔兰）并利用我们实验室针对干细胞生态位内的亚群的独特技术。 拟议的研究具有高度相关性，因为它将揭示有关 TSC 大脑起源的新信息 此外，这项工作广泛适用于许多领域，因为它研究了干细胞如何发挥作用。 具有不同的基础代谢编程和通过生长途径发出信号的潜力，具体取决于 它们在干细胞生态位中的位置。