Genotypic Interactions in Brain Cancer Heterogeneity

脑癌异质性中的基因型相互作用

• 批准号: 10799994
• 负责人: Frank Furnari
• 金额: $ 53.67万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10799994
• 关键词: Acetylation; Adult; Animals; Attenuated; Autoimmune Diseases; Automobile Driving; BRD2 gene; Binding; Biochemical; Bromodomain; Bromodomains and extra-terminal domain inhibitor; Cancer Model; Cell Communication; Cells; Chromatin; Classification; Clinical; Clinical Trials; Coupled; DNA Damage; Data; Disease; Enhancers; Epidermal Growth Factor Receptor; Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor; Excision; Exhibits; Extracellular Domain; Family; Family member; Gene Expression; Gene Expression Profile; Genes; Genetic; Genetic Transcription; Genotype; Glioblastoma; Glioma; Goals; Grant; Heterogeneity; Histones; Human; In Vitro; Individual; Inflammatory; Inflammatory Response; Invaded; Knock-in; Lesion; Lysine; Macrophage; Malignant Neoplasms; Malignant neoplasm of brain; Mediating; Mediator; Mesenchymal; Methods; Microglia; Modeling; Molecular Conformation; Mus; Mutation; Nature; Neurologic; Neurosphere; Newly Diagnosed; Nuclear; Operative Surgical Procedures; PTEN gene; Pathway interactions; Patients; Phenocopy; Phenotype; Population; Primary Brain Neoplasms; Prognosis; Property; Protein Family; Proteins; Radiation therapy; Recurrence; Regulation; Reporter; Resistance; Role; Signal Pathway; Signal Transduction; TNF gene; Tertiary Protein Structure; Testing; Therapeutic; Therapeutic Agents; Therapy trial; Work; avatar models; cancer heterogeneity; cell type; constitutive active receptor; cytokine; epidermal growth factor receptor VIII; genetic signature; improved; in vivo; induced pluripotent stem cell; inhibitor; irradiation; member; molecular subtypes; multiple omics; mutant; neoplastic cell; neurosurgery; novel therapeutics; p65; paracrine; pharmacologic; pre-clinical; protein degradation; radioresistant; recruit; response; restoration; standard of care; temozolomide; therapy resistant; transcriptome; transcriptome sequencing; transmission process; tumor

Project Summary Minimal improvement in the 12-15-month median survival of patients with IDHwt glioblastoma (GBM) has occurred despite advances in neurosurgery, radiation therapy, and clinical trials for novel therapeutics. A central issue confounding successful treatment is the heterogeneous nature of this aggressive tumor. Multi-omics analyses have provided granularity into GBM cellular composition, illustrating that these malignancies can be classified into three molecular subtypes - classical (CL), mesenchymal (MES), and proneural (PN) - with individual tumors typically harboring mixtures of all three subtypes. As a result, multiple spatially distinct, heterotypic populations exist within GBM, making any lesion- or pathway-specific therapy less effective. While considerable effort has been placed on understanding cell intrinsic mechanisms conferring therapeutic resistance, much less is known about interactions between heterotypic GBM cells that contribute to its recalcitrant nature. A hallmark mutation present in 60% of GBM cases is amplification and mutation of the epidermal growth factor receptor (EGFR). The most common EGFR alteration, EGFRvIII, results from structural deletion within its extracellular domain (ECD) yielding a constitutively active receptor which conveys tumor enhancing and therapy resisting functions. Furthermore, EGFRvIII-expressing cells can transmit these properties to amplified EGFRwt cells through pro-survival, paracrine factors,1 akin to TNFα inflammatory signaling. Like TNFα, EGFRvIII activity, specifically in the context of PTEN inactivation, results in NF-κB RelA/p65 nuclear localization, association with members of the acetylated lysine-binding BET (bromodomain and extra terminal domain) family of enhancer proteins, and activation of inflammatory transcription.1 Given the requirement of RelA K310 acetylation (acK310-RelA) for BET bromodomain interactions2 and central role of NF-κB in driving a PN/CL to MES phenotype transition (MESt),3 we postulate that RelA K310 acetylation acts as a regulatory switch controlling MESt and therapy resistance associated with tumors enriched for MES gene signatures.4 The overall goal of this renewal project is to dissect and target mechanisms whereby GBM PN or EGFR-driven CL tumors transition to MES gene expression (collectively referred to here as MES transition (MESt)) and acquire therapeutic resistance through activation of acK310-RelA/BET-mediated inflammatory gene expression. The following lines of experimentation will be employed: 1) biochemical interrogation of the PTEN signaling pathway to determine effectors mediating RelA K310 acetylation and associated MESt, tumor abundance of microglia and macrophages, and resistance to DNA damage; 2) functional analysis of BET family members, BRD2, 3 and 4, through inducible protein degradation, gene editing, bromodomain (BD1, BD2) pharmacological targeting, and assessment of transcription coupled with acK310-RelA/BET enhancer landscape rewiring; and 3) pharmacological interrogation of the PTEN/RelA/BET axis as a means to overcome resistance to salvage radiation therapy in recurrent GBM patients. 1

项目概要 IDHwt 胶质母细胞瘤 (GBM) 患者的 12-15 个月中位生存期略有改善 尽管神经外科、放射治疗和新疗法的临床试验取得了进展，但这种情况还是发生了。一个中央 影响成功治疗的问题是这种侵袭性肿瘤的异质性。多组学 分析提供了 GBM 细胞组成的粒度，表明这些恶性肿瘤可以 分为三种分子亚型 - 经典亚型 (CL)、间充质亚型 (MES) 和原神经亚型 (PN) - 单个肿瘤通常含有所有三种亚型的混合物。结果，多个空间上不同的， GBM 内存在异型群体，使得任何针对病变或途径的特异性治疗效果较差。尽管 人们在理解细胞内在机制方面付出了相当大的努力，从而赋予治疗作用 耐药性，但对于异型 GBM 细胞之间的相互作用知之甚少，而异型 GBM 细胞之间的相互作用有助于其耐药性 桀骜不驯的本性。 60% GBM 病例中存在的标志性突变是基因扩增和突变 表皮生长因子受体（EGFR）。最常见的 EGFR 改变，EGFRvIII，是由结构引起的 其胞外结构域（ECD）内的缺失产生了一种组成型活性受体，可传递肿瘤 增强和治疗抵抗功能。此外，表达 EGFRvIII 的细胞可以传递这些特性 通过类似于 TNFα 炎症信号传导的促生存、旁分泌因子 1 来扩增 EGFRwt 细胞。喜欢 TNFα、EGFRvIII 活性，特别是在 PTEN 失活的情况下，导致 NF-κB RelA/p65 核 定位，与乙酰化赖氨酸结合 BET 的成员（溴结构域和额外末端 域）增强子蛋白家族，以及炎症转录的激活。1 鉴于 RelA 的要求 K310 乙酰化 (acK310-RelA) 用于 BET 布罗莫结构域相互作用2 以及 NF-κB 在驱动 PN/CL 中的核心作用 到 MES 表型转变 (MESt)，3 我们假设 RelA K310 乙酰化充当调节开关 控制与富含 MES 基因特征的肿瘤相关的 MESt 和治疗耐药性。4 该更新项目的总体目标是剖析和瞄准 GBM PN 或 EGFR 驱动的机制 CL 肿瘤转变为 MES 基因表达（此处统称为 MES 转变 (MESt)）并获得 通过激活 acK310-RelA/BET 介导的炎症基因表达来抵抗治疗。这 将采用以下实验：1) PTEN信号通路的生化询问 确定介导 RelA K310 乙酰化和相关 MESt、小胶质细胞肿瘤丰度的效应子 和巨噬细胞，以及对 DNA 损伤的抵抗力； 2) BET家族成员BRD2、3和的功能分析 4、通过诱导蛋白降解、基因编辑、溴结构域（BD1、BD2）药理学靶向，以及 与 acK310-RelA/BET 增强子景观重连相结合的转录评估；和 3) PTEN/RelA/BET 轴的药理学研究作为克服挽救耐药性的手段 复发性 GBM 患者的放射治疗。 1