Regulation of the Hedgehog pathway and Medulloblastoma response to radiochemotherapy

Hedgehog 通路的调节和髓母细胞瘤对放化疗的反应

• 批准号: 10181955
• 负责人: Huadong Pei
• 金额: $ 40.38万
• 依托单位: GEORGE WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-15 至 2021-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10181955
• 关键词: Address; Affect; Antibodies; Biochemical; Cell physiology; Cells; Childhood Brain Neoplasm; Development; Developmental Process; Diagnosis; Disease; Ensure; Erinaceidae; FRAP1 gene; GLI gene; GLI2 gene; Genetic Transcription; Genetically Engineered Mouse; Glioma; Glucose; Goals; Growth; Homeostasis; In Vitro; Investigation; Knowledge; Laboratories; Lead; Ligands; Light; Link; Mass Spectrum Analysis; Mediating; Modeling; Modification; Molecular; Nutrient; O-GlcNAc transferase; Oncogenes; Pathway interactions; Patients; Physiology; Play; Proteins; Proteome; Proteomics; Public Health; Regulation; Research; Role; Science; Signal Transduction; Testing; Therapeutic; Work; base; biophysical techniques; cancer cell; cancer therapy; chemoradiation; design; detection method; effective therapy; experimental study; extracellular; improved; in vivo; insight; medulloblastoma; mortality; multidisciplinary; novel; novel marker; novel therapeutics; nutrition; patient derived xenograft model; personalized medicine; postnatal; response; sensor; smoothened signaling pathway; therapeutic target; transcription factor

Project Summary The Hedgehog (HH) pathway plays a pivotal role in diverse aspects of development and postnatal physiology. Perturbation of the HH pathway and activation of glioma-associated oncogene (GLI), a dedicated transcription factor in this pathway, is responsible for approximately 30% of medulloblastomas (MB), a common and aggressive type of pediatric brain tumor. Therefore, HH signaling has emerged as a therapeutic target for MB therapy. Despite the relevance of these insights to development and disease, substantial gaps still remain in our knowledge of the mechanisms involved in regulation of response to HH signaling and crosstalk with other pathways. Therefore, elucidating the molecular mechanisms of HH signaling is essential to advance our fundamental understanding of both developmental processes and HH-dependent MB. Combining a novel homemade Pan-anti-O-GlcNAc antibody with proteome-wide profiling of O-GlcNAcylated transcription factors by quantitative mass spectrometry, we identified a previously unknown mechanism by which the HH pathway is regulated by glucose-sensing O-GlcNAcylation. Specifically, the core component of the HH pathway (GLI1 and GLI2) is O-GlcNAcylated by O-GlcNAc transferase (OGT), which in turn regulates GLI transcriptional activity. Furthermore, GLI O-GlcNAcylation is regulated by HH ligands and the mTOR/S6K pathway. Importantly, both OGT and GLI O-GlcNAcylation are significantly elevated in MB. OGT inactivation renders MB cancer cells particularly sensitive to radiochemotherapy, suggesting that O-GlcNAcylation could serve as a novel potential therapeutic target for MB. Based on these preliminary findings, we hypothesize that (a) OGT-mediated GLI O- GlcNAcylation activates the HH pathway and promotes MB, and (b) dysregulation of O-GlcNAcylation could affect cancer cell sensitivity to radiochemotherapy. To test this hypothesis, in this application we propose to dissect the molecular mechanisms underlying O-GlcNAcylation-activated GLI in the HH pathway, determine how GLI O-GlcNAcylation is regulated by canonical and non-canonical HH signaling, and decipher the role of the OGT- GLI axis in MB growth in vivo. Our studies could address important questions regarding a novel role of O-GlcNAcylation in HH pathway and radiochemotherapy. Our multifaceted investigation is based on compelling premises and will be carried out with strong scientific rigor, thus promising to fill a major gap of knowledge and have a far-reaching conceptual advance in the field. From the translational perspective, elucidating the significance of O-GlcNAc dysregulation in MB could provide a novel biomarker and a potential alternative therapeutic strategy to treat patients with HH-dependent MB.

项目概要 Hedgehog (HH) 通路在发育和产后生理学的各个方面发挥着关键作用。 HH 通路的扰动和神经胶质瘤相关癌基因 (GLI)（一种专用转录）的激活 该途径中的一个因子，导致大约 30% 的髓母细胞瘤 (MB)，这是一种常见且常见的肿瘤 侵袭性类型的小儿脑肿瘤。因此，HH信号传导已成为MB的治疗靶点 治疗。尽管这些见解与发展和疾病相关，但我们的研究仍然存在巨大差距 了解 HH 信号传导反应调节机制以及与其他物质的串扰 途径。因此，阐明 HH 信号传导的分子机制对于推进我们的研究至关重要。 对发育过程和 HH 依赖性 MB 的基本了解。结合小说 自制泛抗 O-GlcNAc 抗体，具有 O-GlcNAc 酰化转录因子的全蛋白质组分析 通过定量质谱分析，我们发现了一种以前未知的 HH 途径的机制 受葡萄糖感应 O-GlcNAc 酰化调节。具体而言，HH 通路的核心成分（GLI1 和 GLI2) 被 O-GlcNAc 转移酶 (OGT) 酰化，进而调节 GLI 转录活性。 此外，GLI O-GlcNAcylation 受 HH 配体和 mTOR/S6K 通路调节。重要的是，两者 MB 中 OGT 和 GLI O-GlcNAcNA 酰化显着升高。 OGT失活导致MB癌细胞 对放化疗特别敏感，表明 O-GlcNAc 酰化可以作为一种新的潜力 MB 的治疗靶点。基于这些初步发现，我们假设 (a) OGT 介导的 GLI O- GlcNAcylation 激活 HH 通路并促进 MB，并且 (b) O-GlcNAcylation 的失调可以 影响癌细胞对放化疗的敏感性。为了检验这个假设，在这个应用中我们建议 剖析 HH 途径中 O-GlcNAcylation 激活 GLI 的分子机制，确定如何 GLI O-GlcNAc 酰化受经典和非经典 HH 信号传导的调节，并破译了 MB体内生长中的OGT-GLI轴。我们的研究可以解决有关新角色的重要问题 HH 途径和放化疗中的 O-GlcNAc 酰化。我们的多方面调查基于令人信服的 前提并将以严格的科学严谨性进行，从而有望填补知识和领域的重大空白 在该领域取得了深远的概念进步。从翻译的角度阐释 MB 中 O-GlcNAc 失调的重要性可以提供一种新的生物标志物和潜在的替代品 治疗 HH 依赖性 MB 患者的治疗策略。