Therapeutic targeting of the SWI/SNF chromatin remodeler to regulate GBM chemosensitivity

SWI/SNF 染色质重塑剂的治疗靶向调节 GBM 化学敏感性

• 批准号: 10711581
• 负责人: DUANE D MILLER
• 金额: $ 50.4万
• 依托单位: UNIVERSITY OF TENNESSEE HEALTH SCI CTR
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-15 至 2028-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10711581
• 关键词: ATPase Domain; Address; Adult; Alkylating Agents; Binding; Biological; Blood - brain barrier anatomy; Blood Vessels; Brain; Bromodomain; Catalytic Domain; Cell Differentiation process; Cell Line; Cell Maintenance; Cells; Chromatin; Chromatin Modeling; Chromatin Remodeling Factor; Clinical; Complex; Coupled; DNA; Drug Design; Epigenetic Process; Foundations; Future; Gene Expression; Generations; Genes; Genetic Transcription; Glioblastoma; Goals; Histones; Human; Image; Immune; Immune response; Immunocompetent; Immunocompromised Host; In Vitro; Inflammatory; Interferons; Knock-out; Malignant - descriptor; Malignant Neoplasms; Malignant neoplasm of brain; Mediating; Modeling; Molecular; Molecular Target; Mus; Necrosis; Operative Surgical Procedures; Pathway interactions; Patients; Penetrance; Pharmaceutical Preparations; Phenotype; Positioning Attribute; Primary Brain Neoplasms; Prognosis; Property; RNA Polymerase II; Reader; Recurrent tumor; Reducing Agents; Research; Resistance; Role; SMARCA4 gene; SWI/SNF Family Complex; Structure; Surface; Testing; Therapeutic; Therapeutic Intervention; Tumorigenicity; Work; analog; anti-cancer; blood-brain barrier penetration; brahma; cancer cell; candidate identification; chemotherapy; chromatin immunoprecipitation; effective therapy; genetic signature; histone modification; immunoreactivity; improved; in vivo; inhibitor; innovation; knock-down; malignant phenotype; mouse model; multidisciplinary; mutant; neoplastic cell; next generation; novel; novel therapeutic intervention; patient prognosis; pharmacologic; prevent; programs; response; small molecule; stem; stem cell self renewal; stem cells; stemness; targeted treatment; temozolomide; therapeutic target; therapy resistant; transcriptome; transcriptome sequencing; tumor; tumor microenvironment; tumorigenesis

Glioblastoma (GBM) is the most common primary malignancy of the adult brain and is among the most devastating cancers as it is invariably lethal. The perivascular niche and necrotic regions of GBM tumors is enriched for stem-like tumor cells called GBM stem cells (GSCs) that are highly resistant to therapy. Within GBM tumors there are also differentiated cells that are intrinsically resistant, or acquire resistance to, therapy. Thus, there is a critical unmet need to identify and target the molecular pathways that promote GBM cancer stemness, which will enhance GBM sensitivity to currently approved therapies. This proposal is premised on several of our key findings: 1) the BRG1 catalytic subunit of the SWI/SNF chromatin remodeling complex promotes the GBM GSC phenotype and resistance to DNA alkylating agents such as temozolomide (TMZ) used to treat GBM patients; 2) PFI-3, a small molecule BRG1 bromodomain (BRD) inhibitor (BRI), improves GSC sensitivity to DNA alkylating agents by reducing GSC stemness; 3) next generation BRIs were developed that overcome the resistance of TMZ-resistant GBM cell lines, including a potent BRG1-specific BRI (IV-255); and 4) BRIs increase expression of a subclass of interferon (IFN) response genes that are predicted to enhance the anti-tumoral host immune response. Our central hypothesis is that targeting the BRD of BRG1 selectively disrupts GBM GSCs maintenance, which enhances GBM sensitivity to approved therapies and increases GBM immunoreactivity. In Aim 1 we will restore BRG1 expression in BRG1-KD (knockdown) GSCs and in TMZ resistant GBM cells with either wild-type BRG or mutant BRG1 BRD that prevents chromatin binding. We will examine the role of the BRG1 BRD in maintaining the GBM malignant phenotype and therapeutic sensitivity in vitro and in vivo. In Aim 2 we will refine the BRI structure and develop additional small molecule BRG1 BRIs. We will define BRI activity on cancer stemness and therapeutic sensitivity on GBM in vitro and in vivo, and assess selectivity for BRD binding, drug-like properties and optimize BBB penetrance. The anticancer efficacy of BRIs on intracranial GBM tumors will be tested in both immunocompromised and immunocompetent GBM mouse models to define their impact on tumor-associated immune cells. In Aim 3 we will define how BRD targeting of BRG1 reprograms transcription to promote GBM immunoreactivity and inhibit tumorigenesis by performing global transcriptome analysis (RNA-seq), which will be coupled with BRG1 and RNA polymerase II specific ChIP. These BRD-regulated genes will define the BRG1- dependent transcriptome in GSCs, and it also will identify candidate molecular pathways that could be pharmacologically targeted with BRG1 inhibition to get cancer cell synthetic lethality. Our overarching goal is to target BRG1 therapeutically with BRIs combined with presently employed therapies as a novel and urgently required therapeutic approach for this devastating form of brain cancer.

胶质母细胞瘤（GBM）是成人大脑最常见的原发性恶性肿瘤，也是最常见的恶性肿瘤之一 毁灭性的癌症，因为它总是致命的。 GBM肿瘤的血管周围生态位和坏死区域 富含被称为 GBM 干细胞 (GSC) 的干细胞样肿瘤细胞，这些细胞对治疗具有高度抵抗力。 GBM 肿瘤内还存在具有内在耐药性或获得性耐药性的分化细胞 至，治疗。因此，识别和靶向分子途径是一个未得到满足的关键需求。 促进 GBM 癌症干性，这将增强 GBM 对目前批准的疗法的敏感性。这 该提案基于我们的几个关键发现：1) SWI/SNF 的 BRG1 催化亚基 染色质重塑复合物促进 GBM GSC 表型和对 DNA 烷基化的抵抗 用于治疗 GBM 患者的药物，例如替莫唑胺 (TMZ)； 2）PFI-3，小分子BRG1 溴结构域 (BRD) 抑制剂 (BRI) 通过减少 GSC 来提高 GSC 对 DNA 烷化剂的敏感性 干性； 3) 开发了下一代 BRI，克服了 TMZ 耐药性 GBM 的耐药性 细胞系，包括有效的 BRG1 特异性 BRI (IV-255)； 4) BRI 增加子类的表达 预计可增强抗肿瘤宿主免疫反应的干扰素（IFN）反应基因。 我们的中心假设是，针对 BRG1 的 BRD 选择性地破坏 GBM GSC 的维护， 它增强了 GBM 对已批准疗法的敏感性并增加了 GBM 免疫反应性。目标 1 我们将恢复 BRG1-KD（敲低）GSC 和 TMZ 耐药 GBM 细胞中的 BRG1 表达 野生型 BRG 或突变型 BRG1 BRD 可阻止染色质结合。我们将研究的角色 BRG1 BRD 在体外和体内维持 GBM 恶性表型和治疗敏感性 体内。在目标 2 中，我们将完善 BRI 结构并开发其他小分子 BRG1 BRI。我们将 定义 BRI 对癌症干性的活性以及 GBM 的体外和体内治疗敏感性，以及 评估 BRD 结合的选择性、类药特性并优化 BBB 外显率。抗癌 BRI 对颅内 GBM 肿瘤的疗效将在免疫功能低下和 免疫活性 GBM 小鼠模型，以确定其对肿瘤相关免疫细胞的影响。瞄准 3 我们将定义 BRD 如何靶向 BRG1 重编程转录以促进 GBM 免疫反应性 并通过进行全局转录组分析（RNA-seq）来抑制肿瘤发生，这将与 使用 BRG1 和 RNA 聚合酶 II 特异性 ChIP。这些 BRD 调节基因将定义 BRG1- GSC 中依赖的转录组，它还将识别可能的候选分子途径 药理上以 BRG1 抑制为目标，以获得癌细胞的合成杀伤力。我们的首要任务 目标是通过 BRI 与目前采用的疗法相结合来靶向 BRG1 作为一种新的治疗方法 并迫切需要针对这种破坏性脑癌的治疗方法。

项目成果

Next-generation bromodomain inhibitors of the SWI/SNF complex enhance DNA damage and cell death in glioblastoma.

• DOI: 10.1111/jcmm.17907
• 发表时间: 2023-09
• 期刊: JOURNAL OF CELLULAR AND MOLECULAR MEDICINE
• 影响因子: 5.3
• 作者: Yang, Chuanhe;He, Yali;Wang, Yinan;McKinnon, Peter J.;Shahani, Vijay;Miller, Duane D.;Pfeffer, Lawrence M.
• 通讯作者: Pfeffer, Lawrence M.