Sirt2 Inhibition Reprograms T Cell Metabolism to Confer Superior Anti-Tumor Immunity
Ontology highlight
ABSTRACT: Metabolism is a key driver of T cell functions, and the switch from oxidative-phosphorylation to aerobic glycolysis is a hallmark of T cell activation. However, the mechanisms underlying the metabolic switch remain unclear. Here, we report that the Sirtuin-2 (Sirt2) deacetylase protein functions as a metabolic checkpoint that harnesses T cell effector functions and impairs anti-tumor immunity. Specifically, upregulation of Sirt2 expression in human tumor-infiltrating T lymphocytes (TILs) negatively correlates with response to Nivolumab and TIL therapy in non-small cell lung cancer. Mechanistically, Sirt2 suppresses aerobic glycolysis by deacetylating key glycolytic enzymes. Accordingly, Sirt2-deficient T cells manifest increased glycolysis, display enhanced proliferation and effector functions, and have superior anti-tumor activity. Importantly, pharmacologic inhibition of Sirt2 endows human TILs with these superior metabolic fitness and enhanced effector functions. These findings indicate Sirt2 as an actionable target for reprogramming T cell metabolism to augment a broad spectrum of cancer immunotherapies.
Project description:Dysregulated metabolism is a key driver of maladaptive tumor-reactive T lymphocytes within the tumor microenvironment (TME). Actionable mechanisms that rescue the effector activity of anti-tumor T cells in a metabolically restricted TME remain elusive. Here, we report that the Sirtuin-2 (Sirt2) protein deacetylase functions as a master metabolic checkpoint that inhibits T cell metabolic fitness and impairs T cell effector functions and anti-tumor immunity. Mechanistically, Sirt2 suppresses glycolysis and oxidative-phosphorylation (OxPhos) by deacetylating key enzymes involved in glycolysis, tricarboxylic acid (TCA)-cycle, fatty acid oxidation (FAO) and glutaminolysis. Accordingly, Sirt2-deficient T cells exhibit a hyper-metabolic activity with increased glycolysis and OxPhos, resulting in enhanced proliferation and effector functions at tumor beds and subsequently exhibiting superior anti-tumor activity. Importantly, pharmacologic inhibition of Sirt2 endows human lung tumor-infiltrating lymphocytes (TILs) with these superior metabolic fitness and enhanced effector functions. Furthermore, upregulation of Sirt2 expression in human TILs negatively correlates with response to Nivolumab and TIL therapy in non-small cell lung cancer (NSCLC). Our findings unveil Sirt2 as an unexpected actionable target for reprogramming T cell metabolism to augment a broad spectrum of cancer immunotherapies.
Project description:Growing evidence indicates that metabolism is a key driver of T cell functions. A switch from oxidative phosphorylation to aerobic glycolysis is a hallmark of T cell activation and is required to meet metabolic demands of proliferation and effector functions. However, the mechanisms underlying the metabolic switch in T cells remain unclear. Here, we identify Sirt2 as a crucial immune checkpoint coordinating metabolic and functional fitness of T cells. Sirt2 is induced upon T cell activation and increases in late maturation stages. Sirt2 negatively regulates glycolysis by targeting key glycolytic enzymes. Remarkably, Sirt2 knockout T cells exhibit profound upregulation of aerobic glycolysis with enhanced proliferation and effector function and thus effectively reject tumor challenge in vivo. Furthermore, pharmacologic inhibition of Sirt2 in human tumor infiltrating lymphocytes demonstrated a similar phenotype. Taken together, our results demonstrate Sirt2 as an actionable target to reprogram T cell metabolism to augment immunotherapy.
Project description:Growing evidence indicates that metabolism is a key driver of T cell functions. A switch from oxidative phosphorylation to aerobic glycolysis is a hallmark of T cell activation and is required to meet metabolic demands of proliferation and effector functions. However, the mechanisms underlying the metabolic switch in T cells remain unclear. Here, we identify Sirt2 as a crucial immune checkpoint coordinating metabolic and functional fitness of T cells. Sirt2 is induced upon T cell activation and increases in late maturation stages. Sirt2 negatively regulates glycolysis by targeting key glycolytic enzymes. Remarkably, Sirt2 knockout T cells exhibit profound upregulation of aerobic glycolysis with enhanced proliferation and effector function and thus effectively reject tumor challenge in vivo. Furthermore, pharmacologic inhibition of Sirt2 in human tumor infiltrating lymphocytes demonstrated a similar phenotype. Taken together, our results demonstrate Sirt2 as an actionable target to reprogram T cell metabolism to augment immunotherapy.
Project description:Growing evidence indicates that metabolism is a key driver of T cell functions. A switch from oxidative phosphorylation to aerobic glycolysis is a hallmark of T cell activation and is required to meet metabolic demands of proliferation and effector functions. However, the mechanisms underlying the metabolic switch in T cells remain unclear. Here, we identify Sirt2 as a crucial immune checkpoint coordinating metabolic and functional fitness of T cells. Sirt2 is induced upon T cell activation and increases in late maturation stages. Sirt2 negatively regulates glycolysis by targeting key glycolytic enzymes. Remarkably, Sirt2 knockout T cells exhibit profound upregulation of aerobic glycolysis with enhanced proliferation and effector function and thus effectively reject tumor challenge in vivo. Furthermore, pharmacologic inhibition of Sirt2 in human tumor infiltrating lymphocytes demonstrated a similar phenotype. Taken together, our results demonstrate Sirt2 as an actionable target to reprogram T cell metabolism to augment immunotherapy.
Project description:A hallmark of cancer cells is the metabolic switch from oxidative phosphorylation (OXPHOS) to glycolysis, a phenomenon referred to as the “Warburg effect”, which is also observed in primed human pluripotent stem cells (hPSCs). Here, we report that downregulation of SIRT2 and upregulation of SIRT1 is a molecular signature of primed hPSCs and that SIRT2 critically regulates metabolic reprogramming during induced pluripotency by targeting glycolytic enzymes including aldolase, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, and enolase. Remarkably, knockdown of SIRT2 in human fibroblasts resulted in significantly decreased OXPHOS and increased glycolysis. In addition, we found that miR-200c-5p specifically targets SIRT2, downregulating its expression. Furthermore, SIRT2 overexpression in hPSCs significantly affected energy metabolism, altering stem cell functions such as pluripotent differentiation properties. Taken together, our results identify the miR-200c-SIRT2 axis as a key regulator of metabolic reprogramming (Warburg-like effect), via regulation of glycolytic enzymes, during human induced pluripotency and pluripotent stem cell function. To address our hypothesis that acetylation affects the metabolic switch, we compared protein acetylation in hESCs and hDFs by liquid chromatography-tandem mass spectrometry (LCMS/ MS) analyses following immunoprecipitation with acetyl-Lys antibody.
Project description:In order to explore the effects of SIRT2 on the liver metabolic function of mice under metabolic stress, we constructed SIRT2 knockout mice.
Project description:We provide evidence for the essential role of Sirt2 in IFN mediated signaling. Our studies demonstrate that SIRT2 controls expression of key interferon stimulated genes (ISGs) that mediate important biological functions, including anti-viral and antineoplastic responses.
Project description:We demonstrate that transcription factor IRF4 is induced in a T cell receptor (TCR) affinity-dependent manner and functions as a dose-dependent regulator of the metabolic function of activated T cells. IRF4 regulates the expression of key molecules required for aerobic glycolysis of effector T cells, and is essential for clonal expansion and maintenance of effector function of antigen-specific CD8+ T cells. Examination of gene expression profiles in six types of samples
Project description:We demonstrate that transcription factor IRF4 is induced in a T cell receptor (TCR) affinity-dependent manner and functions as a dose-dependent regulator of the metabolic function of activated T cells. IRF4 regulates the expression of key molecules required for aerobic glycolysis of effector T cells, and is essential for clonal expansion and maintenance of effector function of antigen-specific CD8+ T cells. Examination of binding sites of transcription factor IRF4 in mouse CD8+ T cells.
Project description:Natural Killer (NK) cells are predominant innate lymphocytes that provide the early response during infection. NK cells undergo metabolic switch to fuel augmented proliferation and activation following infection. TNFα is a well-known inammatory cytokine that enhances NK cell function, however, a mechanism for stimulation is not well established. Here, we demonstrated that upon infection/inammation, NK cells upregulate the expression of TNF receptor 2 (TNFR2), which is associated with increased proliferation, metabolic activity and effector function. Notably, IL-18 can induce TNFR2 on NK cells, augmenting their sensitivity towards TNFα. Mechanistically, TNFα-TNFR2 signaling induces CD25 (IL-2Rα) expression on NK cells predominantly by autocrine mode, leading to a metabolic switch towards aerobic glycolysis. Accordingly, genetic ablation of TNFR2 curtails the CD25 upregulation and TNFα-induced glycolysis, leading to impaired NK cell proliferation during MCMV infection in vivo. Collectively, our results delineate the crucial role of the TNFα-TNFR2 axis in NK cells for proliferation, glycolysis, and effector function via CD25 induction.