Matching panels of in vivo and in vitro model system of pediatric brain tumors

小儿脑肿瘤体内外模型系统匹配组

• 批准号: 9888891
• 负责人: Xiaonan Li
• 金额: $ 89.73万
• 依托单位: LURIE CHILDREN'S HOSPITAL OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-03 至 2025-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/9888891
• 关键词: Address; Affect; Autopsy; Biological; Biological Assay; Biological Availability; Biological Models; Biology; Brain; Brain Neoplasms; Brain Stem; Cancer Etiology; Cancer Model; Cell Survival; Cells; Cerebellum; Cerebrum; Child; Childhood; Childhood Brain Neoplasm; Childhood Malignant Brain Tumor; Coculture Techniques; Collection; Cryopreservation; Development; Ependymoma; Epigenetic Process; Future; Gene-Modified; Genetic; Goals; Growth; Growth Factor; Hypoxia; In Vitro; Intracranial Neoplasms; Location; Malignant neoplasm of brain; Methylation; Modeling; Molecular; Mus; Mutation; Operative Surgical Procedures; Organoids; Patients; Play; Positioning Attribute; Proliferating; Protocols documentation; Radiation; Radiation therapy; Resistance; Role; Series; Source; Starvation; Testing; Tissues; Treatment Protocols; Tumor Biology; Tumor Cell Biology; Tumor Stem Cells; Tumor Tissue; Validation; Xenograft Model; Xenograft procedure; brain cell; brain tissue; cancer stem cell; cancer survival; cell type; childhood cancer mortality; histone methylation; histone modification; implantation; in vitro Model; in vivo; in vivo Model; medulloblastoma; molecular subtypes; mouse model; multiple omics; neoplastic cell; new combination therapies; novel therapeutics; radioresistant; response; self-renewal; single-cell RNA sequencing; small molecule; subventricular zone; tumor; tumor xenograft

Project Summary Brain tumors are the leading cause of cancer-related death in children. Poor understanding of the interactions between tumor cells, especially cancer stem cells (CSCs), and normal brain tissues have played a role. Due to the difficulties of obtaining tumor tissues, there is a limited availability of biologically accurate and matched in vitro (tumor organoid) and in vivo (PDOX) model systems. Normal brain tissue is more difficult to obtain, making it nearly impossible to develop normal brain organoids. To overcome these barriers, we propose to utilize our existing (n=127) and future established patient derived orthotopic xenograft (PDOX) models as the source supply of tumor cells to develop matching tumor organoids. These PDOX models replicate the biology of original patient tumors and represent a wide spectrum of the newly discovered molecular subtypes of malignant brain tumors. Using 24 PDOX models, we have established 13 (54.1%) tumor organoids. Recognizing the rarity of normal brain tissues, we propose to use autopsied tissues. Indeed, we have cryopreserved viable cells of normal cerebrum, cerebellum, brain stem, and sub-ventricular zone cells from children of different ages and showed that the autopsied cerebral cells can proliferate in vitro to form neurospheres. We, therefore, hypothesize that 1) autopsied normal brain tissues and PDOX models can provide critically needed and biologically accurate cells for the development of normal and tumor organoid, and 2) the growth of these organoid are dependent on the growth factor milieu of their location and modulated by the dynamic interactions between different types of cells. Radiation therapy is one of the most important treatment regimens for pediatric brain tumors. Since mutation of histone modification genes are frequent in pediatric brain tumors, our 3rd hypothesis is that such epigenetic changes affect responses and resistance toward radiation, and successful targeting in organoid and PDOX tumors will lead to new combination therapies. We propose three Specific Aims. Aim 1: Develop normal brain organoids from autopsied normal cerebrum, cerebellum, brain stem and subventricle zone from all age groups and establish tumoral organoids from PDOX models and identify their location- and developmental-stage dependent niche factor combinations, respectively. Aim 2: Understand the dynamic interactions between tumor (CSCs and non-stem tumor) cells and normal brain cells. We will use co-culture assays to identify the niche factor combinations that dictate cellular diversity and survival of CSC and normal brain cells, and perform global multi-omics analysis and single cell RNAseq to elucidate the molecular mechanisms, followed by in vivo validation of our findings in PDOX models. Aim 3: Determine the role of histone methylation in regulating CSC survival and self-renewal of malignant brain tumors when perturbed by radiation. We will use normal and tumoral organoids to determine how pre-existing histone methylation status affect their survival and to identify key radiation-resistant methylation(s) by combining radiation with an informer set of small-molecule probes that selectively target distinct nodes in tumor epigenetic regulatory circuity in organoids and in PDOX models.

项目摘要 脑肿瘤是儿童癌症相关死亡的主要原因。对相互作用的理解不足 肿瘤细胞，特别是癌症干细胞（CSC）和正常脑组织之间的相互作用发挥了作用。由于 由于获得肿瘤组织的困难，生物学准确和匹配的可用性有限， 体外（肿瘤类器官）和体内（PDOX）模型系统。正常的脑组织更难获得， 几乎不可能发育出正常的脑类器官。为了克服这些障碍，我们建议利用我们的 现有（n=127）和未来建立的患者源性原位异种移植（PDOX）模型作为来源供应 肿瘤细胞发展成匹配的肿瘤类器官。这些PDOX模型复制了原始患者的生物学 肿瘤，并代表了广泛的新发现的恶性脑肿瘤的分子亚型。 使用24个PDOX模型，我们建立了13个（54.1%）肿瘤类器官。认识到正常的罕见性 脑组织，我们建议使用尸检组织事实上，我们冷冻保存了正常人的活细胞， 大脑，小脑，脑干和脑室下区细胞从不同年龄的儿童，并显示 尸检的脑细胞可以在体外增殖形成神经球。因此，我们假设：（1） 尸检的正常脑组织和PDOX模型可以提供急需的和生物学上准确的细胞 正常和肿瘤类器官的发育，和2）这些类器官的生长依赖于 生长因子环境的位置，并通过不同类型的细胞之间的动态相互作用进行调节。 放射治疗是小儿脑肿瘤最重要的治疗方案之一。由于突变 组蛋白修饰基因在儿童脑肿瘤中很常见，我们的第三个假设是，这种表观遗传 变化影响对辐射的反应和抵抗力，并成功靶向类器官和PDOX 肿瘤将导致新的联合疗法。我们提出三个具体目标。目标1：开发正常的大脑 所有年龄组尸检正常大脑、小脑、脑干和脑室下区的类器官 从PDOX模型中建立肿瘤类器官，并确定它们的位置和发育阶段 依赖生态位因子组合。目的2：了解肿瘤之间的动态相互作用 (CSCs和非干细胞肿瘤）细胞和正常脑细胞。我们将使用共培养分析来确定生态位 决定CSC和正常脑细胞的细胞多样性和存活的因素组合， 多组学分析和单细胞RNAseq以阐明分子机制，然后进行体内 验证我们在PDOX模型中的发现。目的3：确定组蛋白甲基化在CSC调控中的作用 生存和自我更新的恶性脑肿瘤时受到辐射干扰。我们将使用正常和肿瘤 类器官，以确定预先存在的组蛋白甲基化状态如何影响它们的存活，并确定关键的 通过将辐射与一组小分子探针结合， 选择性靶向类器官和PDOX模型中肿瘤表观遗传调节回路中的不同节点。