Mechanisms of Hedgehog signaling in glioblastoma

胶质母细胞瘤中 Hedgehog 信号传导机制

• 批准号: 10208542
• 负责人: David R Raleigh
• 金额: $ 53.45万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10208542
• 关键词: Adult; Agonist; Astrocytes; BMP5 gene; BMP7 gene; Biology; Brain; CRISPR interference; Cancer Etiology; Cell membrane; Cells; Cerebrum; Cilia; Clinical Data; Clinical Trials; Coculture Techniques; DIF factor; Data; Defect; Development; Erinaceidae; Extracellular Matrix; Gene Activation; Gene Expression; Gene Targeting; Genes; Genetic Transcription; Glioblastoma; Goals; Growth; Human; Ligands; Light; Malignant - descriptor; Malignant Neoplasms; Malignant neoplasm of brain; Malignant neoplasm of central nervous system; Malignant neoplasm of urinary bladder; Modeling; Mus; Organoids; Pathway interactions; Patients; Pharmacology; Process; Research; Role; SHH gene; Signaling Protein; Structure; Surface; System; Testing; Tissue Differentiation; Vertebrates; Work; adult stem cell; base; bone morphogenic protein; cancer cell; cancer stem cell; cell motility; cell type; clinically relevant; experimental study; flexibility; human pluripotent stem cell; improved; in vivo; innovation; insight; live cell imaging; migration; molecular scale; morphogens; novel; patient derived xenograft model; pre-clinical; programs; single-cell RNA sequencing; smoothened signaling pathway; stem cell division; stem cell homeostasis; stem cells; targeted treatment; transcriptome sequencing; tumor; tumor growth; tumor microenvironment; tumor progression; tumorigenesis

Project summary Glioblastomas are deadly tumors and account for approximately half of all malignant primary brain cancers. Glioblastoma stem cells exist in interchangeable cellular states that are influenced by the tumor microenvironment, and there is a paucity of information concerning the cellular mechanisms responsible for communicating between glioblastoma cells and the tumor stroma. The Hedgehog pathway, which directs gene expression programs that are essential for development and adult stem cell homeostasis, is critical for survival of glioblastoma stem cells. Paradoxically, a clinical trial suggested that pharmacologic inhibition of the Hedgehog pathway accelerates glioblastoma growth. These clinical data provide an opportunity to re-evaluate how the Hedgehog pathway functions in cancer, and suggest that the role of Hedgehog signaling in glioblastoma stem cells remains to be elucidated. This proposal focuses on understanding how inhibition of the Hedgehog pathway drives glioblastoma at the tumor, cellular, and molecular scale. To do so, our proposal incorporates a novel astrocyte organoid model of glioblastoma that facilitates live imaging of cellular interactions within the tumor microenvironment. When integrated with CRISPR interference, pharmacology, and mouse syngeneic and patient derived xenograft models of glioblastoma, our innovative organoid system will facilitate previously impossible experiments to understand glioblastoma biology. Based on our preliminary organoid, in vivo, and single cell RNA sequencing data presented in this application, we hypothesize that cancer cell-extrinsic Hedgehog signaling in the tumor microenvironment restrains glioblastoma stem cell-renewal and invasion by inducing differentiation factors and remodeling the extracellular matrix. We will test this hypothesis by defining how Hedgehog signals are transduced through the glioblastoma microenvironment; determining if cancer-cell extrinsic Hedgehog signaling restrains glioblastoma stem cells by inducing bone morphogenic protein signaling; and determining if Hedgehog signaling restrains glioblastoma cell invasion by inducing genes that regulate migration through the extracellular matrix. This approached is based on the premise that by studying the mechanisms of Hedgehog signaling in glioblastoma, we will discover new insights into how glioblastoma cells communicate with the tumor microenvironment. Indeed, we know surprisingly little about how interactions between glioblastoma cells and the tumor microenvironment influence cancer progression, and almost nothing about how astrocytes, which comprise the majority of cell types in the adult brain, influence glioblastoma invasion or tumorigenesis. Though the objective of this proposal is to broadly improve our understanding of the mechanisms of Hedgehog signaling in glioblastoma, a long-term goal of this research is to understand these processes well enough to consider targeted therapeutic strategies to improve survival from glioblastoma. Thus, this work will explain why Hedgehog pathway inhibition unexpectedly accelerates glioblastoma growth, elucidate targetable mechanisms, and provide the preclinical basis for new clinical trials in glioblastoma patients.

项目概要 胶质母细胞瘤是致命的肿瘤，约占所有恶性原发性脑癌的一半。 胶质母细胞瘤干细胞以受肿瘤影响的可互换的细胞状态存在 微环境，并且缺乏有关负责的细胞机制的信息 胶质母细胞瘤细胞和肿瘤基质之间的通讯。 Hedgehog 通路，指导基因 对于发育和成体干细胞稳态至关重要的表达程序对于生存至关重要 胶质母细胞瘤干细胞。矛盾的是，一项临床试验表明，刺猬蛋白的药理抑制作用 途径加速胶质母细胞瘤的生长。这些临床数据提供了重新评估如何 Hedgehog 通路在癌症中发挥作用，并表明 Hedgehog 信号在胶质母细胞瘤干细胞中的作用 细胞仍有待阐明。该提案的重点是了解如何抑制 Hedgehog 通路 在肿瘤、细胞和分子尺度上驱动胶质母细胞瘤。为此，我们的提案纳入了一项新颖的 胶质母细胞瘤的星形胶质细胞类器官模型，有助于肿瘤内细胞相互作用的实时成像 微环境。当与 CRISPR 干扰、药理学和小鼠同系和 患者衍生的胶质母细胞瘤异种移植模型，我们的创新类器官系统将促进以前 了解胶质母细胞瘤生物学的不可能的实验。基于我们初步的类器官、体内和 本申请中提供的单细胞 RNA 测序数据，我们假设癌细胞外源性 肿瘤微环境中的刺猬信号传导抑制胶质母细胞瘤干细胞的更新和侵袭 诱导分化因子并重塑细胞外基质。我们将通过定义来检验这个假设 Hedgehog 信号如何通过胶质母细胞瘤微环境转导；确定是否有癌细胞 外源性 Hedgehog 信号通过诱导骨形态发生蛋白信号传导抑制胶质母细胞瘤干细胞； 并确定 Hedgehog 信号传导是否通过诱导调节基因来抑制胶质母细胞瘤细胞侵袭 通过细胞外基质迁移。这种方法的前提是通过研究 胶质母细胞瘤中 Hedgehog 信号传导机制，我们将发现胶质母细胞瘤细胞如何发挥作用的新见解 与肿瘤微环境沟通。事实上，我们对相互作用如何进行知之甚少。 胶质母细胞瘤细胞和肿瘤微环境之间几乎没有任何影响癌症进展的因素 关于星形胶质细胞（成人大脑中大多数细胞类型）如何影响胶质母细胞瘤侵袭 或肿瘤发生。尽管该提案的目的是广泛提高我们对 Hedgehog 信号在胶质母细胞瘤中的机制，这项研究的长期目标是了解这些 过程足够好，可以考虑有针对性的治疗策略来提高胶质母细胞瘤的生存率。因此， 这项工作将解释为什么 Hedgehog 通路抑制意外地加速胶质母细胞瘤的生长，阐明 靶向机制，并为胶质母细胞瘤患者的新临床试验提供临床前基础。