Defining PRC1.1 as a gatekeeper of lineage plasticity and response to anti-GD2 therapy

将 PRC1.1 定义为谱系可塑性和抗 GD2 治疗反应的看门人

基本信息

批准号：
10644278
负责人：
Nathaniel Mabe
金额：
$ 14.72万
依托单位：
DANA-FARBER CANCER INST
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-05-09 至 2025-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10644278
关键词：
Adoption Adrenergic Agents Advisory Committees Antigens CRISPR screen Cell Line Cell Maintenance Cell surface Cells Cephalic Chemistry Chemoresistance Chromatin Committee Members Complex Credentialing Dependence Development Disease Down-Regulation EZH2 gene Enhancers Enzymes Epigenetic Process Gangliosides Gatekeeping Gene Expression Genes Genetic Genetic Transcription Glycolipids Goals Heterogeneity Immunooncology Immunotherapy In Vitro Individual Intervention Knock-out Knowledge Link Malignant Childhood Neoplasm Malignant Neoplasms Maps Mediating Mesenchymal Mining Modeling Neural Crest Neuroblastoma Neuronal Differentiation PRC1 Protein Pathology Pathway interactions Patients Pharmacology Polycomb Postdoctoral Fellow Protein Subunits Proteins Refractory Regulation Repression Resistance Role Solid Neoplasm Testing Therapeutic Therapeutic Intervention Tissues Training Tretinoin Variant Work combinatorial design early childhood high risk in vivo inhibitor loss of function member nerve stem cell neuroblastoma cell novel strategies pediatric patients pharmacologic prevent programs resistance mechanism response single cell sequencing single-cell RNA sequencing small molecule inhibitor targeted treatment therapeutic target therapy resistant transcription factor tumor

项目摘要

Project Summary Epigenetic dysregulation is frequently observed in pediatric cancers, including neuroblastoma (NB), the most common extracranial solid tumor in pediatric patients. In my postdoctoral work, I identified that a cell state transition from an adrenergic to a mesenchymal epigenetic state is associated with the loss of GD2 expression and resistance to anti-GD2 therapy. Given the important role of anti-GD2 therapy in treating high-risk neuroblastoma patients, I designed a CRISPR-Cas9 screening platform to study epigenetic regulators of GD2 expression. I identified that individual knockout of several members of the PRC1.1/BCOR complex increases GD2 expression in GD2-low cell lines. AIM 1 will establish the relationship between the PRC1.1/BCOR complex and GD2 regulation by rigorously testing the necessity of the PRC1.1 complex to maintain low ST8SIA1 expression in mesenchymal cell lines. Mining genetic dependencies across 25 tumor lineages, I identified that the PRC1.1 complex is an enriched dependency in neuroblastoma independently of its ability to regulate GD2 expression. AIM 2 will validate that the gene PCGF1, the top enriched PRC1.1 subunit dependency in neuroblastoma, is a genetic dependency in multiple models of neuroblastoma. I will intersect chromatin and single-cell RNA-sequencing studies to determine the consequences of PCGF1 knockout on chromatin regulation and differentiation/cell state trajectories. No known small molecule inhibitors of PRC1.1 currently exist. The correlation of USP7 genetic dependency in the Dependency Map portal against all other gene dependencies revealed a strong correlation with PCGF1 dependency, suggesting a tractable pharmacologic approach to inhibiting PRC1.1. AIM 3 will establish USP7 inhibition as a mechanism to modulate PRC1.1 activity. These specific aims will test the capacity of highly potent and selective USP7 inhibitor to selectively upregulate GD2 expression and reduce neuroblastoma viability in vitro and in vivo. I anticipate that these findings will directly link PRC1.1 to epigenetic state and differentiation in neuroblastoma. Moreover, it will credential USP7 inhibition as a combinatorial therapy to restore the response to anti-GD2 therapy and directly target neuroblastoma cells. To complete the studies in this proposal, I will apply my strong expertise in epigenetics and pharmacology. To fill in critical gaps in knowledge and expand my scientific training, I’ve assembled a training plan that includes advisory committee members that are experts in immuno-oncology, single-cell sequencing, and USP7 chemistry. This proposal lays a strong framework for my long-term goal of establishing a lab that focuses on targeting epigenetic plasticity/heterogeneity as an intervention to overcome therapeutic resistance.

项目概要表观遗传失调在儿科癌症中经常观察到，包括神经母细胞瘤 (NB) 在我的博士后工作中，我发现了一种细胞状态。从肾上腺素能状态到间充质表观遗传状态的转变与 GD2 表达的丧失相关鉴于抗 GD2 治疗在治疗高风险中的重要作用。神经母细胞瘤患者，我设计了一个 CRISPR-Cas9 筛选平台来研究 GD2 的表观遗传调节因子我发现 PRC1.1/BCOR 复合体的几个成员的单独敲除会增加。 GD2-low 细胞系中的 GD2 表达将建立 PRC1.1/BCOR 复合物之间的关系。和 GD2 监管，严格测试 PRC1.1 复合体维持低 ST8SIA1 的必要性在间充质细胞系中表达。通过挖掘 25 个肿瘤谱系的遗传依赖性，我发现 PRC1.1 复合体是一个神经母细胞瘤中丰富的依赖性与其调节 GD2 表达的能力无关。验证基因 PCGF1（神经母细胞瘤中最富集的 PRC1.1 亚基依赖性）是一种遗传基因我将交叉染色质和单细胞 RNA 测序。研究确定 PCGF1 敲除对染色质调节和分化/细胞状态的影响轨迹。目前尚无已知的 PRC1.1 小分子抑制剂存在与 USP7 遗传的相关性。依赖关系图门户中对所有其他基因依赖关系的依赖关系揭示了很强的相关性与 PCGF1 依赖性，表明抑制 PRC1.1 的易处理的药理学方法将。建立 USP7 抑制作为调节 PRC1.1 活性的机制。这些具体目标将测试能力。高效、选择性 USP7 抑制剂，选择性上调 GD2 表达并减少神经母细胞瘤体外和体内的活力。我预计这些发现将直接将 PRC1.1 与表观遗传状态和分化联系起来。此外，它还证明 USP7 抑制是恢复反应的联合疗法。抗 GD2 疗法并直接靶向神经母细胞瘤细胞为了完成本提案中的研究，我将申请。我在表观遗传学和药理学方面的强大专业知识填补了知识方面的关键空白并扩展了我的知识。科学培训，我制定了一个培训计划，其中包括咨询委员会成员，他们是以下领域的专家该提案为我的免疫肿瘤学、单细胞测序和 USP7 化学奠定了坚实的框架。长期目标是建立一个专注于表观遗传可塑性/异质性作为研究对象的实验室干预以克服治疗抵抗。