Metabolic Barriers to T Cell Activation in Clear Cell Renal Cell Carcinoma

透明细胞肾细胞癌中 T 细胞激活的代谢障碍

• 批准号: 10375526
• 负责人: Jeffrey C. Rathmell
• 金额: $ 43.05万
• 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 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10375526
• 关键词: Bypass; CD8-Positive T-Lymphocytes; CD8B1 gene; Cell physiology; Cells; Cellular Metabolic Process; Characteristics; Clear cell renal cell carcinoma; Data; Defect; Disease; Dose; Down-Regulation; Enzymes; Eragrostis; Genetic; Genetic Transcription; Genotype; Glucose; Glutaminase; Glutamine; Glycolysis; Goals; Granzyme; HIF1A gene; Human; Hypoxia; Immune; Immune system; Immunity; Immunosuppression; Immunotherapy; Impairment; Interleukin-2; Intervention; Lead; Lymphocyte Function; Malignant Neoplasms; Mediating; Metabolic; Metabolic Pathway; Metabolic dysfunction; Metabolism; Mitochondria; Modeling; Mus; Mutation; Nutrient; Operative Surgical Procedures; PD-1 blockade; PD-1/PD-L1; Pathway interactions; Patient Selection; Patients; Peripheral; Population; Proliferating; Public Health; Pyruvate; Reactive Oxygen Species; Reporting; Sampling; Signal Transduction; T cell response; T-Cell Activation; T-Lymphocyte; T-cell receptor repertoire; Testing; Tissue Sample; Tumor Immunity; Tumor Suppressor Proteins; Tumor-Infiltrating Lymphocytes; cancer cell; cancer immunotherapy; cancer therapy; cell behavior; checkpoint therapy; cohort; cytokine; cytotoxic; design; effector T cell; glucose metabolism; glucose uptake; immune activation; immune checkpoint blockade; immune function; immunoregulation; improved; insight; interest; kidney cortex; lifetime risk; mitochondrial metabolism; mouse model; neoplastic cell; peripheral blood; prognostic; programmed cell death protein 1; receptor; response; success; tumor; tumor metabolism; tumor microenvironment; uptake

SUMMARY Exploiting the immune system to eliminate cancer cells has been a goal for many years, but it has become apparent that tumors actively suppress immune cell functions. While inhibition of immunomodulatory receptors, such as through PD-1 checkpoint blockade therapy, holds tremendous promise, this treatment is effective in only a portion of patients. Factors that determine immune responsiveness against tumors remain largely uncertain. Our data show, however, that the metabolic demands of T cells may be a critical factor in the success of immunotherapy. We have shown that effector T cell (Teff) activation requires high rates of glucose and anabolic metabolism yet cancer cells and the tumor microenvironment can inhibit Teff metabolic pathways. This may represent a fundamental mechanism of tumor-mediated immune suppression. To better understand the influence of the tumor microenvironment on T cell metabolism and improve immunotherapies, we have examined tumor infiltrating lymphocytes (TIL) from surgically-excised human clear cell Renal Cell Carcinoma (ccRCC) tumor samples, a cancer responsive to PD-1 blockade and with a prognostic immune signature. ccRCC is highly associated with mutations and loss of the Von Hippel Lindau (VHL) tumor suppressor, which leads to stabilization of HIF1α and HIF2α and induction of a transcriptional pseudo-hypoxic response that alters the tumor to promote an immune suppressive microenvironment that can negatively impact ccRCC CD8 TIL function and anti-tumor immunity. We found CD8 TIL are abundant in ccRCC, yet these cells are uniformly PD-1high and functionally suppressed. In addition, CD8 TIL had multiple metabolic impairments and were unable to efficiently uptake glucose or perform glycolysis and had small, fragmented mitochondria that produced high levels of Reactive Oxygen Species (ROS). Importantly, neutralization of ROS or provision of the glycolytic end-product pyruvate could partially rescue ccRCC CD8 TIL function. Glutamine is also a key nutrient to support mitochondrial metabolism for T cells through glutaminolysis and we report here that inhibition or genetic deletion of the first enzyme in this pathway, Glutaminase 1 (GLS1), leads to a compensatory increase in glycolysis that can enhance cytotoxic CD8 function. This proposal will test the hypothesis that the ccRCC microenvironment impairs glycolysis and leads to accumulation of dysfunctional mitochondria in CD8 TIL and that rescue of TIL glycolysis will enhance T cell response to immunotherapy. We will study primary ccRCC tumors and mouse RCC models to: (1) Determine how mitochondria are dysregulated and impair activation and metabolism of ccRCC CD8 TIL; (2) Investigate if promoting glucose uptake or inhibiting GLS1 to enhance glucose metabolism can improve the metabolism and function of CD8 TIL; and (3) Test how PD-1 blockade therapy impacts T cell metabolism and functional populations in ccRCC. Together, these studies will establish the mechanism of metabolic dysfunction in ccRCC TIL and test if approaches to enhance T cell glycolysis can improve cancer immunotherapy.

概括 利用免疫系统消除癌细胞多年来一直是一个目标，但它已经成为 显然，肿瘤在抑制免疫调节的同时主动抑制免疫细胞功能。 受体，例如通过 PD-1 检查点阻断疗法，具有巨大的前景，这种疗法是 仅对部分患者有效。决定肿瘤免疫反应的因素仍然存在。 然而，我们的数据表明，T 细胞的代谢需求可能是一个关键因素。 我们已经证明，效应 T 细胞 (Teff) 的激活需要高浓度的葡萄糖。 和合成代谢，但癌细胞和肿瘤微环境可以抑制 Teff 代谢途径。 这可能代表了肿瘤介导的免疫抑制的基本机制。 肿瘤微环境对T细胞代谢的影响并改进免疫治疗，我们有 检查来自手术切除的人透明细胞肾细胞癌的肿瘤浸润淋巴细胞（TIL） (ccRCC) 肿瘤样本，一种对 PD-1 阻断有反应且具有预后免疫特征的癌症。 ccRCC 与 Von Hippel Lindau (VHL) 肿瘤抑制基因的突变和缺失高度相关， 导致 HIF1α 和 HIF2α 稳定并诱导转录假性缺氧反应， 改变肿瘤以促进免疫抑制微环境，从而对 ccRCC CD8 产生负面影响 TIL功能和抗肿瘤免疫我们发现ccRCC中CD8 TIL丰富，但这些细胞是均匀的。 PD-1 高且功能受到抑制，此外，CD8 TIL 具有多种代谢损伤并受到抑制。 无法有效地摄取葡萄糖或进行糖酵解，并且线粒体小且碎片化， 产生高水平的活性氧（ROS），重要的是，中和活性氧或提供活性氧。 糖酵解终产物丙酮酸可以部分挽救 ccRCC CD8 TIL 功能，谷氨酰胺也是一个关键。 通过谷氨酰胺分解支持 T 细胞线粒体代谢的营养物质，我们在此报告 抑制或基因删除该途径中的第一种酶谷氨酰胺酶 1 (GLS1)，会导致 糖酵解的代偿性增加可以增强细胞毒性 CD8 功能。 假设 ccRCC 微环境损害糖酵解并导致功能失调的积累 CD8 TIL 中的线粒体和 TIL 糖酵解的拯救将增强 T 细胞对免疫治疗的反应。 将研究原发性 ccRCC 肿瘤和小鼠 RCC 模型，以：(1) 确定线粒体的功能 (2) 考察是否促进血糖 摄取或抑制GLS1增强糖代谢可改善CD8的代谢和功能 (3) 测试 PD-1 阻断疗法如何影响 ccRCC 中的 T 细胞代谢和功能群。 这些研究将共同​​建立 ccRCC TIL 代谢功能障碍的机制，并测试是否 增强 T 细胞糖酵解的方法可以改善癌症免疫治疗。