Browse
Submit Data
Databases
API
Help

Dataset Information

29 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

TET2 promotes anti-tumor immunity by governing G-MDSCs and CD8⁺ T-cell numbers.

ABSTRACT: The host immune response is a fundamental mechanism for attenuating cancer progression. Here we report a role for the DNA demethylase and tumor suppressor TET2 in host anti-tumor immunity. Deletion of Tet2 in mice elevates IL-6 levels upon tumor challenge. Elevated IL-6 stimulates immunosuppressive granulocytic myeloid-derived suppressor cells (G-MDSCs), which in turn reduce CD8⁺ T cells upon tumor challenge. Consequently, systematic knockout of Tet2 in mice leads to accelerated syngeneic tumor growth, which is constrained by anti-PD-1 blockade. Removal of G-MDSCs by the anti-mouse Ly6g antibodies restores CD8⁺ T-cell numbers in Tet2^-/- mice and reboots their anti-tumor activity. Importantly, anti-IL-6 antibody treatment blocks the expansion of G-MDSCs and inhibits syngeneic tumor growth. Collectively, these findings reveal a TET2-mediated IL-6/G-MDSCs/CD8⁺ T-cell immune response cascade that safeguards host adaptive anti-tumor immunity, offering a cell non-autonomous mechanism of TET2 for tumor suppression.

SUBMITTER: Li S

PROVIDER: S-EPMC7534639 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

TET2 promotes anti-tumor immunity by governing G-MDSCs and CD8+ T cell numbers

Project description:Host immune response is a fundamental mechanism for attenuating cancer progression. Here we report a pivotal role of the DNA demethylase and tumor suppressor TET2 played in host antitumor immunity. Deletion of Tet2 dramatically elevated the IL-6 level in Tet2-/- mice upon tumor challenge. The elevated IL-6 greatly stimulated the immunosuppressive granulocytic myeloid-derived suppressor cells (G-MDSCs), which in turn significantly reduced CD8+ T cells upon tumor challenge. Consequently, systematic knockout of the Tet2 in mice led to accelerated syngeneic tumor growth, which was constrained by anti-PD-1 blockade. Removal of G-MDSCs by the anti-mouse Ly6g Ab restored the numbers of CD8+ T cells in Tet2-/- mice and rebooted their anti-tumor activity. Importantly, anti-IL-6 Ab treatment blocked the expansion of G-MDSCs and inhibited syngeneic tumor growth. Collectively, these findings reveal a TET2-mediated IL-6/G-MDSC/CD8+ T immune response cascade that safeguards host adaptive anti-tumor immunity, offering a cell non-autonomous mechanism of TET2 for tumor suppression.

2020-08-04 | GSE144787 | GEO

TET2 promotes anti-tumor immunity by governing G-MDSCs and CD8+ T cell numbers

Project description:TET2 promotes anti-tumor immunity by governing G-MDSCs and CD8+ T cell numbers

| PRJNA604913 | ENA

Tim-4+ cavity-resident macrophages impair anti-tumor CD8+ T cell immunity.

Project description:Immune checkpoint blockade (ICB) has been a remarkable clinical advance for cancer; however, the majority of patients do not respond to ICB therapy. We show that metastatic disease in the pleural and peritoneal cavities is associated with poor clinical outcomes after ICB therapy. Cavity-resident macrophages express high levels of Tim-4, a receptor for phosphatidylserine (PS), and this is associated with reduced numbers of CD8+ T cells with tumor-reactive features in pleural effusions and peritoneal ascites from patients with cancer. We mechanistically demonstrate that viable and cytotoxic anti-tumor CD8+ T cells upregulate PS and this renders them susceptible to sequestration away from tumor targets and proliferation suppression by Tim-4+ macrophages. Tim-4 blockade abrogates this sequestration and proliferation suppression and enhances anti-tumor efficacy in models of anti-PD-1 therapy and adoptive T cell therapy in mice. Thus, Tim-4+ cavity-resident macrophages limit the efficacy of immunotherapies in these microenvironments.

| S-EPMC9115604 | biostudies-literature

Autotaxin impedes anti-tumor immunity by suppressing chemotaxis and tumor infiltration of CD8+ T cells.

Project description:Autotaxin (ATX; ENPP2) produces lysophosphatidic acid (LPA) that regulates multiple biological functions via cognate G protein-coupled receptors LPAR1-6. ATX/LPA promotes tumor cell migration and metastasis via LPAR1 and T cell motility via LPAR2, yet its actions in the tumor immune microenvironment remain unclear. Here, we show that ATX secreted by melanoma cells is chemorepulsive for tumor-infiltrating lymphocytes (TILs) and circulating CD8+ T cells ex vivo, with ATX functioning as an LPA-producing chaperone. Mechanistically, T cell repulsion predominantly involves Gα12/13-coupled LPAR6. Upon anti-cancer vaccination of tumor-bearing mice, ATX does not affect the induction of systemic T cell responses but, importantly, suppresses tumor infiltration of cytotoxic CD8+ T cells and thereby impairs tumor regression. Moreover, single-cell data from melanoma tumors are consistent with intratumoral ATX acting as a T cell repellent. These findings highlight an unexpected role for the pro-metastatic ATX-LPAR axis in suppressing CD8+ T cell infiltration to impede anti-tumor immunity, suggesting new therapeutic opportunities.

| S-EPMC8761359 | biostudies-literature

Tumor suppressor TET2 promotes cancer immunity and immunotherapy efficacy.

Project description:Loss-of-function mutations in genes encoding TET DNA dioxygenase occur frequently in hematopoietic malignancy, but rarely in solid tumors which instead commonly have reduced activity. The impact of decreased TET activity in solid tumors is not known. Here we show that TET2 mediates interferon γ (IFNγ)-JAK-STAT signaling pathway to control chemokine and PD-L1 expression, lymphocyte infiltration and cancer immunity. IFNγ stimulated STAT1 to bind TET2 and recruit TET2 to hydroxymethylate chemokine and PD-L1 genes. Reduced TET activity was associated with decreased TH1-type chemokines and tumor-infiltrating lymphocytes (TILs) and the progression of human colon cancer. Deletion of Tet2 in murine melanoma and colon tumor cells reduced chemokine expression and TILs, enabling tumors to evade anti-tumor immunity and to resist anti-PD-L1 therapy. Conversely, stimulating TET activity by systematic injection of its co-factor, ascorbate/vitamin C, increased chemokine and TILs, leading to enhanced anti-tumor immunity and anti-PD-L1 efficacy and extended lifespan of tumor-bearing mice. These results suggest an IFNγ-JAK-STAT-TET signaling pathway that mediates tumor response to anti-PD-L1/PD-1 therapy and is frequently disrupted in solid tumors. Our findings also suggest TET activity as a biomarker for predicting the efficacy and patient response to anti-PD-1/PD-L1 therapy, and stimulating TET activity as an adjuvant immunotherapy of solid tumors.

| S-EPMC6763236 | biostudies-literature

Localized expression of GITR-L in the tumor microenvironment promotes CD8+ T cell dependent anti-tumor immunity.

Project description:The systemic administration of an agonist antibody against glucocorticoid-induced tumor necrosis factor receptor related (GITR) protein has been shown to be effective in overcoming immune tolerance and promoting tumor rejection in a variety of murine tumor models. However, little is known regarding the functional consequence of ligation of GITR with its natural ligand (GITR-L) in the context of regulatory T cell (Treg) suppression in vivo. To determine the mechanism of GITR-L action in vivo, we generated a panel of tumor cell clones that express varying levels of GITR-L. The ectopic expression of GITR-L on the tumor cell surface was sufficient to enhance anti-tumor immunity and delay tumor growth in syngeneic BALB/c mice. Within the range examined, the extent of anti-tumor activity in vivo did not correlate with the level of GITR-L expression, as all clones tested exhibited a similar delay in tumor growth. The localized expression of GITR-L on tumor cells led to a significant increase in CD8+ T cell infiltration compared to the levels seen in control tumors. The increased proportion of CD8+ T cells was only observed locally at the tumor site and was not seen in the tumor draining lymph node. Depletion studies showed that CD8+ T cells, but not CD4+ T cells, were required for GITR-L mediated protection against tumor growth. These studies demonstrate that signaling between GITR-L and GITR in the tumor microenvironment promotes the infiltration of CD8+ T cells, which are essential for controlling tumor growth.

| S-EPMC2822720 | biostudies-literature

Tissue-resident memory CD8+ T cells amplify anti-tumor immunity by triggering antigen spreading through dendritic cells.

Project description:Tissue-resident memory CD8+ T (Trm) cells mediate potent local innate and adaptive immune responses and play a central role against solid tumors. However, whether Trm cells cross-talk with dendritic cells (DCs) to support anti-tumor immunity remains unclear. Here we show that antigen-specific activation of skin Trm cells leads to maturation and migration to draining lymph nodes of cross-presenting dermal DCs. Tumor rejection mediated by Trm cells triggers the spread of cytotoxic CD8+ T cell responses against tumor-derived neo- and self-antigens via dermal DCs. These responses suppress the growth of intradermal tumors and disseminated melanoma lacking the Trm cell-targeted epitope. Moreover, analysis of RNA sequencing data from human melanoma tumors reveals that enrichment of a Trm cell gene signature associates with DC activation and improved survival. This work unveils the ability of Trm cells to amplify the breath of cytotoxic CD8+ T cell responses through DCs, thereby strengthening anti-tumor immunity.

| S-EPMC6765014 | biostudies-literature

PI3K?/? inhibition promotes anti-tumor immunity through direct enhancement of effector CD8+ T-cell activity.

Project description:PI3K inhibitors with differential selectivity to distinct PI3K isoforms have been tested extensively in clinical trials, largely to target tumor epithelial cells. PI3K signaling also regulates the immune system and inhibition of PI3K? modulate the tumor immune microenvironment of pre-clinical mouse tumor models by relieving T-regs-mediated immunosuppression. PI3K inhibitors as a class and PI3K? specifically are associated with immune-related side effects. However, the impact of mixed PI3K inhibitors in tumor immunology is under-explored. Here we examine the differential effects of AZD8835, a dual PI3K?/? inhibitor, specifically on the tumor immune microenvironment using syngeneic models. Continuous suppression of PI3K?/? was not required for anti-tumor activity, as tumor growth inhibition was potentiated by an intermittent dosing/schedule in vivo. Moreover, PI3K?/? inhibition delivered strong single agent anti-tumor activity, which was associated with dynamic suppression of T-regs, improved CD8+ T-cell activation and memory in mouse syngeneic tumor models. Strikingly, AZD8835 promoted robust CD8+ T-cell activation dissociated from its effect on T-regs. This was associated with enhancing effector cell viability/function. Together these data reveal novel mechanisms by which PI3K?/? inhibitors interact with the immune system and validate the clinical compound AZD8835 as a novel immunoncology drug, independent of effects on tumor cells. These data support further clinical investigation of PI3K pathway inhibitors as immuno-oncology agents.

| S-EPMC6307194 | biostudies-literature

A microparticle platform for STING-targeted immunotherapy enhances natural killer cell- and CD8+ T cell-mediated anti-tumor immunity.

Project description:Immunotherapies have significantly improved cancer patient survival, but response rates are still limited. Thus, novel formulations are needed to expand the breadth of immunotherapies. Pathogen associated molecular patterns (PAMPs) can be used to stimulate an immune response, but several pathogen recognition receptors are located within the cell, making delivery challenging. We have employed the biodegradable polymer acetalated dextran (Ace-DEX) to formulate PAMP microparticles (MPs) in order to enhance intracellular delivery. While treatment with four different PAMP MPs resulted in tumor growth inhibition, cyclic GMP-AMP (cGAMP) MPs were most effective. cGAMP MPs showed anti-tumor efficacy at doses 100-1000 fold lower than published doses of soluble cGAMP in two murine tumor models. Treatment with cGAMP MPs resulted in increased natural killer cell numbers in the tumor environment. Immune cell depletion studies confirmed that NK cells were responsible for the anti-tumor efficacy in an aggressive mouse melanoma model. NK cells and CD8+ T cells were both required for early anti-tumor function in a triple negative breast cancer model. In summary, cGAMP MP treatment results in NK and T cell-dependent anti-tumor immune response.

| S-EPMC6594365 | biostudies-literature

CDK4/6 inhibition promotes anti-tumor immunity

Project description:Pharmacologicalinhibitors of cyclin dependent kinases 4 and 6 (CDK4/6) are an approvedtreatment forhormone receptor-positive breast cancer and are currently under evaluation across hundreds of clinical trials for other cancertypes. The clinical success of these inhibitorsis largely attributedto well-defined tumor-intrinsic cytostatic mechanisms, while their emerging role as immunomodulatory agents is lessunderstood. Usingintegrated epigenomic, transcriptomic and proteomicanalyses, we demonstrateda novel action of CDK4/6inhibitorsin promoting the phenotypic and functional acquisition of immunological T cell memory.Short-term priming with a CDK4/6inhibitorpromoted long-termendogenousanti-tumor T cell immunityin mice, enhanced the persistence and therapeutic efficacy of chimeric antigen receptor (CAR)-T cells, and induced an RB-dependent T cell phenotype supportive offavorable responses to immune checkpoint blockade in melanoma patients.Together, thesemechanistic insights significantlybroaden the prospective utility of CDK4/6 inhibitors as clinical tools to boostanti-tumorT cell immunity.

2021-06-08 | PXD026539 | Pride