Metabolic interactions between tumor cells and the immunce system in GBM A potential Achilles heel of GBM for novel therapeutics

摘要 背景：我们最近发现胶质母细胞瘤(GBM)包含具有不同代谢的细胞群 要求，具有利用有氧糖酵解的快速循环细胞(FCC)和耐治疗的慢循环 细胞(SCCs)优先参与脂质代谢。不同的肿瘤细胞如何与免疫细胞相互作用 这种代谢的异质性如何塑造GBM的免疫格局尚不清楚。 目标/假设：本研究的目的是了解儿童心理健康状况下的沟通机制 肿瘤微环境，特别是表征干细胞之间的代谢相互作用(a 导致疾病进展和复发的治疗抵抗人群)和免疫隔间。 在这里，我们将研究GBM内的细胞间通信模型，其中SCC塑造 免疫抑制的肿瘤环境，反过来通过为干细胞提供脂质来承担对它们的代谢支持， 它们对鳞状细胞的新陈代谢和功能是必不可少的。重要的是，我们将测试多个基因和临床 顺从的药理学方法，破坏这种代谢相互作用，以拮抗GBM。 具体目标：我们的具体目标将是：1)剖析干细胞与肿瘤微环境的关系， 2)描绘了招募的免疫抑制细胞如何介导SCC驱动的肿瘤进展，以及3)建立 免疫浸润物通过提供脂质为干细胞提供代谢支持。 研究设计：将破译GBM中肿瘤异质性与肿瘤免疫状况之间的联系 并对这些细胞间的代谢相互作用进行了具体的研究。 在目标1中，我们将通过调查来描绘细胞谱系(SCC和FCC)与免疫浸润的关系 利用单细胞RNA测序技术和GeoMx Digital，研究它们的基因组图谱和空间组织 分别进行了空间侧写。我们还将评估特定的脂肪因子Lipocalin-2在形成 免疫微环境。在目标2中，我们将使用多种方法破坏巨噬细胞、髓系细胞- 衍生的抑制细胞和调节性T细胞隔间，并比较其对存活、生长和 SCC和FCC对化疗的敏感性。在目标3中，荧光标记脂质的使用与FLOW相结合 细胞术和时间推移成像将能够比较免疫细胞、FCC和 SCCS。最后，活体实验将检验靶向脂类运输(抑制FABP3或 APOE)或脂肪生成(他汀类药物治疗)通过影响SCC和呈现总体 肿瘤对化疗更敏感。基于最近报道的他汀类药物与免疫系统的协同作用 检查点抑制剂，我们还将评估他汀类药物与抗PD-1治疗的组合。 影响：该项目成功完成，将验证治疗上顺从的方法 改善脑肿瘤相关发病率和死亡率的代谢沟通。

ABSTRACT Background: We recently revealed that glioblastoma (GBM) contain cell populations with distinct metabolic requirements, with fast-cycling cells (FCCs) harnessing aerobic glycolysis, and treatment-resistant slow-cycling cells (SCCs) preferentially engaging lipid metabolism. How the different tumor cells interact with immune cells and how this metabolic heterogeneity shapes the immune landscape in GBM has yet to be understood. Objectives/Hypothesis: The objectives of this study are to understand the mechanisms of communication in the tumor microenvironment, specifically to characterize the metabolic interactions between SCCs (a therapeutically resistant population that drive disease progression and recurrence) and the immune compartment. Here, we will investigate a model of intercellular communication within GBM where SCCs shape an immunosuppressive tumor milieu, which in turn assume metabolic support to SCCs by providing them with lipids, which are essential for SCC metabolism and function. Importantly, we will test multiple genetic and clinically amenable pharmacological approaches disrupting this metabolic interplay to antagonize GBM. Specific aims: Our specific aims will be 1) Dissect the relationship of SCCs with the tumor microenvironment, 2) Delineate how recruited immune suppressive cell mediate SCC-driven tumor progression, and 3) Establish that immune infiltrates provide metabolic support to SCCs by providing lipids. Study design: The link between tumor heterogeneity and tumor immune landscape in GBM will be deciphered with specific investigations of the metabolic interplay taking place between these cellular compartments. In aim 1, we will delineate the cell lineage (SCC vs FCC) relationship with immune infiltrates by investigating their genomic profile and spatial organization, using single cell RNA sequencing technology and GeoMx Digital Spatial Profiling, respectively. We will also evaluate the role of the specific adipokine, Lipocalin-2, in shaping the immune microenvironment. In aim 2 we will employ multiple approaches disrupting the macrophage, myeloid- derived suppressor cell, and regulatory T cell compartments, and compare the effect on survival, growth and chemotherapy sensitivity of SCCs and FCCs. In aim 3 the use of fluorescently labeled lipids combined with flow cytometry and time lapse imaging will enable the comparison of lipid transfer between immune cells, FCCs and SCCs. Finally, in vivo experiments will test the hypothesis that targeting lipid trafficking (inhibition of FABP3 or ApoE) or lipogenesis (statin treatment) provide therapeutic benefits by affecting SCCs and rendering the overall tumor more responsive to chemotherapy. Based on the recently reported synergistic effect of statins with immune checkpoint inhibitors, we will also evaluate the combination of statins with anti PD-1 therapy. Impact: Successfully completed, this project will validate therapeutically amenable approaches targeting metabolic communication to improve brain tumor associated morbidity and mortality.