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.

总结 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剂（ICB）。然而，这些方法受到挑战， 肿瘤可以通过多种机制抑制抗肿瘤免疫并使其有效 只有一部分患者。我们已经表明，效应T细胞需要高速率的葡萄糖摄取，以促进合成代谢。 肿瘤细胞和肿瘤微环境（TME）破坏了抗肿瘤代谢，现在很明显， 免疫力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 从手术切除的人透明细胞肾细胞中检测肿瘤浸润淋巴细胞（TIL 癌（ccRCC），一种具有中等ICB应答率的癌症，其特征是Von Hippel-Lindau（VHL）肿瘤抑制因子。这些肿瘤使我们能够证明葡萄糖和谷氨酰胺都是 在TME中可用，而葡萄糖代谢促进效应T细胞，谷氨酰胺代谢抑制效应T细胞， T细胞效应子功能。目前还不清楚哪些谷氨酰胺依赖酶或代谢物抑制T细胞，但 我们发现，谷氨酰胺酶缺乏改变了组蛋白甲基化，并降低了PI3K-3受体Pik3ip3的表达。 抑制PI3K/mTORC1信号传导和炎症效应细胞因子产生的抑制性蛋白。 为了进一步探索谷氨酰胺抑制T细胞的机制，我们在小鼠中进行了体内CRISPR筛选。 在所有谷氨酰胺代谢酶中， 有效增加TIL的积累。我们还直接定义了细胞类型特异性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 在代谢中，肿瘤相关巨噬细胞（TAM）是葡萄糖的主要消耗者，其次是TIL， 而癌细胞则优先消耗谷氨酰胺。有趣的是，Vhl的损失并没有增加， 葡萄糖摄取的RCC细胞在体内，而是增加葡萄糖摄取的TIL和TAM。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， 在治疗开始前和治疗开始后3周，来自患者纵向队列的外周血。这种方法 特异性鉴定罕见但高度增殖的ICB应答性CD8和CD4 T细胞， 线粒体电位基于这些发现，我们假设RCC遗传学驱动代谢， 具有丰富谷氨酰胺的免疫抑制性TME抑制PI3K信号传导以损伤T细胞 效应子分化和功能。我们将研究原发性人类ccRCC肿瘤和小鼠RCC模型，以： (1)测试ccRCC TME中的营养物质和肿瘤遗传学如何影响TIL功能和代谢;以及（2） 确定TME中葡萄糖和谷氨酰胺代谢如何促进或抑制抗肿瘤免疫。 总之，这些研究将建立谷氨酰胺损害T细胞分化的机制，并测试新的 克服TME中的代谢免疫抑制以提高抗肿瘤免疫的潜在靶点。