Metabolic barriers to T cell activation in clear cell renal cell carcinoma

透明细胞肾细胞癌中 T 细胞活化的代谢障碍

• 批准号: 10532599
• 负责人: Jeffrey C. Rathmell
• 金额: $ 55.33万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10532599
• 关键词: 3-Dimensional; Address; Affect; CD4 Positive T Lymphocytes; CD80 gene; CD8B1 gene; CRISPR screen; CTLA4 gene; Cancer Etiology; Cell Shape; Cell physiology; Cells; Cellularity; Clear cell renal cell carcinoma; Complex; Consumption; Dissociation; Enzymes; Genes; Genetic; Glucose; Glutamate-Ammonia Ligase; Glutamates; Glutaminase; Glutamine; Glycolysis; Human; Hypoxia; Immune; Immune system; Immunity; Immunosuppression; Immunotherapy; Impairment; In Vitro; Inflammatory; Intercellular Fluid; Intervention; Longitudinal cohort; Lymphocyte Function; Malignant Neoplasms; Mediating; Mediator; Metabolic; Metabolic Pathway; Metabolism; Mitochondria; Modeling; Mus; Nutrient; Nutrient availability; Operative Surgical Procedures; Organoids; PD-1/PD-L1; PIK3CG gene; Pathway interactions; Patients; Play; Population; Positron-Emission Tomography; Primary Neoplasm; Process; Production; Proteins; Radiolabeled; Resources; Role; Sampling; Shapes; Signal Transduction; T cell differentiation; T-Cell Activation; T-Lymphocyte; Testing; Tracer; Tumor Immunity; Tumor Promotion; Tumor Suppressor Proteins; Tumor Tissue; Tumor-Infiltrating Lymphocytes; Tumor-associated macrophages; Waste Products; antagonist; cancer cell; cancer therapy; cancer type; cell type; cytokine; effector T cell; glucose metabolism; glucose uptake; high dimensionality; histone methylation; immune activation; immune checkpoint blockade; improved; in vivo; kidney cortex; neoplastic cell; novel therapeutics; peripheral blood; response; restraint; standard of care; targeted treatment; tumor; tumor metabolism; tumor microenvironment; tumor-immune system interactions; uptake

SUMMARY Exploiting immunity to eliminate cancer cells offers tremendous new therapeutic opportunities, including the widely employed immune checkpoint blockade (ICB) agents. These approaches are challenged, however, by the multitude of mechanisms through which tumors can suppress anti-tumor immunity and render them effective in only a portion of patients. We have shown that effector T cells require high rates of glucose uptake for anabolic metabolism, and it is now apparent that cancer cells and the tumor microenvironment (TME) disrupt anti-tumor immunity in part through metabolic immune suppression. To address this barrier to immunotherapy, we examined tumor infiltrating lymphocytes (TIL) from surgically excised samples of human clear cell Renal Cell Carcinoma (ccRCC), a cancer with moderate rates of ICB response that is characterized by loss of the Von Hippel-Lindau (VHL) tumor suppressor. These tumors allowed us to show that both glucose and glutamine are available in the TME and while glucose metabolism promotes effector T cells, metabolism of glutamine restrains T cell effector function. It is unclear which glutamine-dependent enzymes or metabolites suppress T cells, but we found that Glutaminase-deficiency altered histone methylation and reduced expression of Pik3ip3, a PI3K- inhibitory protein that suppresses PI3K/mTORC1 signaling and production of inflammatory effector cytokines. To further explore mechanisms of T cell suppression by glutamine, we performed an in vivo CRISPR screen in primary TIL and found loss of Glutamine Synthetase among all glutamine-metabolizing enzymes to most effectively increase TIL accumulation. We also directly defined cell type-specific glucose and glutamine usage in the TME using radiolabeled Positron Emission Tomography tracers. In contrast to classic Warburg metabolism, tumor associated macrophages (TAM) were the dominant consumers of glucose, followed by TIL, and cancer cells, which instead preferentially consumed glutamine. Interestingly, loss of Vhl did not increase glucose uptake of RCC cells in vivo but instead increased glucose uptake in TIL and TAM. To explore these pathways in patients undergoing ICB therapy, we next performed high dimensional CyTOF analyses of peripheral blood from a longitudinal cohort of patients before and 3 weeks after start of therapy. This approach specifically identified rare but highly proliferative ICB-responsive CD8 and CD4 T cells with elevated mitochondrial potential. Based on these findings, we hypothesize that RCC genetics drive a metabolically immunosuppressive TME with abundant glutamine that suppresses PI3K signaling to impair T cell effector differentiation and function. We will study primary human ccRCC tumors and mouse RCC models to: (1) Test how nutrients in the ccRCC TME and tumor genetics influence TIL function and metabolism; and (2) Determine how glucose and glutamine metabolism in the TME promote or suppress anti-tumor immunity. Together, these studies will establish mechanisms by which glutamine impairs T cell differentiation and test new potential targets to overcome metabolic immune suppression in the TME to improve anti-tumor immunity.

概括 利用免疫力消除癌细胞提供了巨大的新治疗机会，包括 广泛使用的免疫检查点阻断（ICB）剂。然而，这些方法受到了挑战 肿瘤通过多种机制抑制抗肿瘤免疫并使其有效 仅在一部分患者中。我们已经证明效应 T 细胞需要高速率的葡萄糖摄取来进行合成代谢 新陈代谢，现在很明显癌细胞和肿瘤微环境（TME）会破坏抗肿瘤作用 免疫部分通过代谢免疫抑制。为了解决免疫治疗的这一障碍，我们 检查手术切除的人透明细胞肾细胞样本中的肿瘤浸润淋巴细胞 (TIL) 癌 (ccRCC)，一种具有中等 ICB 反应率的癌症，其特征是 Von 缺失 Hippel-Lindau (VHL) 肿瘤抑制剂。这些肿瘤使我们能够证明葡萄糖和谷氨酰胺都是 TME 中存在葡萄糖代谢促进效应 T 细胞，而谷氨酰胺代谢则抑制 T 细胞效应功能。目前尚不清楚哪些谷氨酰胺依赖性酶或代谢物会抑制 T 细胞，但 我们发现谷氨酰胺酶缺乏会改变组蛋白甲基化并减少 Pik3ip3（一种 PI3K- 抑制 PI3K/mTORC1 信号传导和炎症效应细胞因子产生的抑制蛋白。 为了进一步探索谷氨酰胺抑制 T 细胞的机制，我们在体内进行了 CRISPR 筛选 初级 TIL 并发现大多数谷氨酰胺代谢酶中谷氨酰胺合成酶缺失 有效增加TIL积累。我们还直接定义了细胞类型特异性的葡萄糖和谷氨酰胺的使用 在 TME 中使用放射性标记的正电子发射断层扫描示踪剂。与经典的瓦尔堡相比 代谢中，肿瘤相关巨噬细胞 (TAM) 是葡萄糖的主要消耗者，其次是 TIL， 和癌细胞，它们反而优先消耗谷氨酰胺。有趣的是，Vhl 的损失并没有增加 体内 RCC 细胞的葡萄糖摄取增加，但 TIL 和 TAM 中的葡萄糖摄取增加。去探索这些 在接受 ICB 治疗的患者中，我们接下来进行了高维 CyTOF 分析 治疗开始前和治疗后 3 周的纵向队列患者的外周血。这种做法 特别鉴定出罕见但高度增殖的 ICB 反应性 CD8 和 CD4 T 细胞，其升高 线粒体电位。基于这些发现，我们假设 RCC 遗传学驱动代谢 含有丰富谷氨酰胺的免疫抑制性 TME，可抑制 PI3K 信号传导，从而损害 T 细胞 效应器分化和功能。我们将研究原发性人类 ccRCC 肿瘤和小鼠 RCC 模型，以便： (1) 测试ccRCC TME和肿瘤遗传学中的营养物质如何影响TIL功能和代谢；和（2） 确定 TME 中的葡萄糖和谷氨酰胺代谢如何促进或抑制抗肿瘤免疫。 这些研究将共同​​建立谷氨酰胺损害 T 细胞分化的机制并测试新的 克服 TME 中代谢免疫抑制以提高抗肿瘤免疫力的潜在目标。