RESUMO
Our bodies are equipped with powerful immune surveillance to clear cancerous cells as they emerge. How tumor-initiating stem cells (tSCs) that form and propagate cancers equip themselves to overcome this barrier remains poorly understood. To tackle this problem, we designed a skin cancer model for squamous cell carcinoma (SCC) that can be effectively challenged by adoptive cytotoxic T cell transfer (ACT)-based immunotherapy. Using single-cell RNA sequencing (RNA-seq) and lineage tracing, we found that transforming growth factor ß (TGF-ß)-responding tSCs are superior at resisting ACT and form the root of tumor relapse. Probing mechanism, we discovered that during malignancy, tSCs selectively acquire CD80, a surface ligand previously identified on immune cells. Moreover, upon engaging cytotoxic T lymphocyte antigen-4 (CTLA4), CD80-expressing tSCs directly dampen cytotoxic T cell activity. Conversely, upon CTLA4- or TGF-ß-blocking immunotherapies or Cd80 ablation, tSCs become vulnerable, diminishing tumor relapse after ACT treatment. Our findings place tSCs at the crux of how immune checkpoint pathways are activated.
Assuntos
Transferência Adotiva , Carcinoma de Células Escamosas/imunologia , Imunidade Celular , Vigilância Imunológica , Células-Tronco Neoplásicas/imunologia , Neoplasias Cutâneas/imunologia , Linfócitos T/imunologia , Animais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/imunologia , Células-Tronco Neoplásicas/patologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia , Linfócitos T/patologiaRESUMO
Although clonal neo-antigen burden is associated with improved response to immune therapy, the functional basis for this remains unclear. Here we study this question in a novel controlled mouse melanoma model that enables us to explore the effects of intra-tumor heterogeneity (ITH) on tumor aggressiveness and immunity independent of tumor mutational burden. Induction of UVB-derived mutations yields highly aggressive tumors with decreased anti-tumor activity. However, single-cell-derived tumors with reduced ITH are swiftly rejected. Their rejection is accompanied by increased T cell reactivity and a less suppressive microenvironment. Using phylogenetic analyses and mixing experiments of single-cell clones, we dissect two characteristics of ITH: the number of clones forming the tumor and their clonal diversity. Our analysis of melanoma patient tumor data recapitulates our results in terms of overall survival and response to immune checkpoint therapy. These findings highlight the importance of clonal mutations in robust immune surveillance and the need to quantify patient ITH to determine the response to checkpoint blockade.
Assuntos
Heterogeneidade Genética/efeitos da radiação , Melanoma/genética , Melanoma/imunologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Raios Ultravioleta/efeitos adversos , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Estudos de Coortes , Modelos Animais de Doenças , Feminino , Humanos , Linfócitos do Interstício Tumoral , Melanoma/mortalidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Mutação/efeitos da radiação , Filogenia , Neoplasias Cutâneas/mortalidade , Taxa de Sobrevida , Linfócitos T/imunologia , Microambiente Tumoral/imunologia , Microambiente Tumoral/efeitos da radiaçãoRESUMO
Roquin and Regnase-1 proteins bind and post-transcriptionally regulate proinflammatory target messenger RNAs to maintain immune homeostasis. Either the sanroque mutation in Roquin-1 or loss of Regnase-1 cause systemic lupus erythematosus-like phenotypes. Analyzing mice with T cells that lack expression of Roquin-1, its paralog Roquin-2 and Regnase-1 proteins, we detect overlapping or unique phenotypes by comparing individual and combined inactivation. These comprised spontaneous activation, metabolic reprogramming and persistence of T cells leading to autoimmunity. Here, we define an interaction surface in Roquin-1 for binding to Regnase-1 that included the sanroque residue. Mutations in Roquin-1 impairing this interaction and cooperative regulation of targets induced T follicular helper cells, germinal center B cells and autoantibody formation. These mutations also improved the functionality of tumor-specific T cells by promoting their accumulation in the tumor and reducing expression of exhaustion markers. Our data reveal the physical interaction of Roquin-1 with Regnase-1 as a hub to control self-reactivity and effector functions in immune cell therapies.
Assuntos
Autoimunidade , Citotoxicidade Imunológica , Imunoterapia Adotiva , Melanoma Experimental/terapia , Proteínas Repressoras/metabolismo , Ribonucleases/metabolismo , Neoplasias Cutâneas/terapia , Linfócitos T/transplante , Ubiquitina-Proteína Ligases/metabolismo , Animais , Feminino , Células HEK293 , Células HeLa , Humanos , Imunidade Humoral , Masculino , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Fenótipo , Ligação Proteica , Proteínas Repressoras/genética , Ribonucleases/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Microambiente Tumoral , Ubiquitina-Proteína Ligases/genéticaRESUMO
Although the pathological significance of tumor-associated macrophage (TAM) heterogeneity is still poorly understood, TAM reprogramming is viewed as a promising anticancer therapy. Here we show that a distinct subset of TAMs (F4/80hiCD115hiC3aRhiCD88hi), endowed with high rates of heme catabolism by the stress-responsive enzyme heme oxygenase-1 (HO-1), plays a critical role in shaping a prometastatic tumor microenvironment favoring immunosuppression, angiogenesis and epithelial-to-mesenchymal transition. This population originates from F4/80+HO-1+ bone marrow (BM) precursors, accumulates in the blood of tumor bearers and preferentially localizes at the invasive margin through a mechanism dependent on the activation of Nrf2 and coordinated by the NF-κB1-CSF1R-C3aR axis. Inhibition of F4/80+HO-1+ TAM recruitment or myeloid-specific deletion of HO-1 blocks metastasis formation and improves anticancer immunotherapy. Relative expression of HO-1 in peripheral monocyte subsets, as well as in tumor lesions, discriminates survival among metastatic melanoma patients. Overall, these results identify a distinct cancer-induced HO-1+ myeloid subgroup as a new antimetastatic target and prognostic blood marker.
Assuntos
Biomarcadores Tumorais/metabolismo , Heme Oxigenase-1/metabolismo , Neoplasias Pulmonares/imunologia , Melanoma/imunologia , Neoplasias Cutâneas/imunologia , Macrófagos Associados a Tumor/imunologia , Animais , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/sangue , Linhagem Celular Tumoral/transplante , Quimioterapia Adjuvante/métodos , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/imunologia , Feminino , Heme/metabolismo , Heme Oxigenase-1/antagonistas & inibidores , Heme Oxigenase-1/sangue , Heme Oxigenase-1/genética , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/terapia , Masculino , Melanoma/mortalidade , Melanoma/secundário , Melanoma/terapia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Células Progenitoras Mieloides/imunologia , Células Progenitoras Mieloides/metabolismo , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia , Evasão Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/metabolismoRESUMO
Group 2 innate lymphoid cells (ILC2s) are essential to maintain tissue homeostasis. In cancer, ILC2s can harbor both pro-tumorigenic and anti-tumorigenic functions, but we know little about their underlying mechanisms or whether they could be clinically relevant or targeted to improve patient outcomes. Here, we found that high ILC2 infiltration in human melanoma was associated with a good clinical prognosis. ILC2s are critical producers of the cytokine granulocyte-macrophage colony-stimulating factor, which coordinates the recruitment and activation of eosinophils to enhance antitumor responses. Tumor-infiltrating ILC2s expressed programmed cell death protein-1, which limited their intratumoral accumulation, proliferation and antitumor effector functions. This inhibition could be overcome in vivo by combining interleukin-33-driven ILC2 activation with programmed cell death protein-1 blockade to significantly increase antitumor responses. Together, our results identified ILC2s as a critical immune cell type involved in melanoma immunity and revealed a potential synergistic approach to harness ILC2 function for antitumor immunotherapies.
Assuntos
Anticorpos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Interleucina-33/farmacologia , Linfócitos/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Quimiotaxia de Leucócito/efeitos dos fármacos , Citotoxicidade Imunológica/efeitos dos fármacos , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Eosinófilos/metabolismo , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Linfócitos/imunologia , Linfócitos/metabolismo , Masculino , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/metabolismoRESUMO
CTLA-4 immune checkpoint blockade is clinically effective in a subset of patients with metastatic melanoma. We identify a subcluster of MAGE-A cancer-germline antigens, located within a narrow 75 kb region of chromosome Xq28, that predicts resistance uniquely to blockade of CTLA-4, but not PD-1. We validate this gene expression signature in an independent anti-CTLA-4-treated cohort and show its specificity to the CTLA-4 pathway with two independent anti-PD-1-treated cohorts. Autophagy, a process critical for optimal anti-cancer immunity, has previously been shown to be suppressed by the MAGE-TRIM28 ubiquitin ligase in vitro. We now show that the expression of the key autophagosome component LC3B and other activators of autophagy are negatively associated with MAGE-A protein levels in human melanomas, including samples from patients with resistance to CTLA-4 blockade. Our findings implicate autophagy suppression in resistance to CTLA-4 blockade in melanoma, suggesting exploitation of autophagy induction for potential therapeutic synergy with CTLA-4 inhibitors.
Assuntos
Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Epigênese Genética , Mutação em Linhagem Germinativa , Neoplasias/genética , Neoplasias/imunologia , Animais , Anticorpos Monoclonais/uso terapêutico , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Autofagia , Linhagem Celular Tumoral , Metilação de DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Imunoterapia , Ipilimumab/farmacologia , Masculino , Melanoma/genética , Melanoma/imunologia , Antígenos Específicos de Melanoma/genética , Antígenos Específicos de Melanoma/imunologia , Camundongos , Camundongos Transgênicos , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologiaRESUMO
Homeostatic programs balance immune protection and self-tolerance. Such mechanisms likely impact autoimmunity and tumor formation, respectively. How homeostasis is maintained and impacts tumor surveillance is unknown. Here, we find that different immune mononuclear phagocytes share a conserved steady-state program during differentiation and entry into healthy tissue. IFNγ is necessary and sufficient to induce this program, revealing a key instructive role. Remarkably, homeostatic and IFNγ-dependent programs enrich across primary human tumors, including melanoma, and stratify survival. Single-cell RNA sequencing (RNA-seq) reveals enrichment of homeostatic modules in monocytes and DCs from human metastatic melanoma. Suppressor-of-cytokine-2 (SOCS2) protein, a conserved program transcript, is expressed by mononuclear phagocytes infiltrating primary melanoma and is induced by IFNγ. SOCS2 limits adaptive anti-tumoral immunity and DC-based priming of T cells in vivo, indicating a critical regulatory role. These findings link immune homeostasis to key determinants of anti-tumoral immunity and escape, revealing co-opting of tissue-specific immune development in the tumor microenvironment.
Assuntos
Interferon gama/imunologia , Melanoma/imunologia , Monócitos/imunologia , Metástase Neoplásica/patologia , Neoplasias Cutâneas/imunologia , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Microambiente Tumoral , Animais , Diferenciação Celular , Células Dendríticas/imunologia , Homeostase , Humanos , Melanoma/genética , Melanoma/patologia , Camundongos , Monócitos/patologia , Análise de Sequência de RNA , Análise de Célula Única , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , TranscriptomaRESUMO
CD8+ T cell exhaustion is a state of dysfunction acquired in chronic viral infection and cancer, characterized by the formation of Slamf6+ progenitor exhausted and Tim-3+ terminally exhausted subpopulations through unknown mechanisms. Here we establish the phosphatase PTPN2 as a new regulator of the differentiation of the terminally exhausted subpopulation that functions by attenuating type 1 interferon signaling. Deletion of Ptpn2 in CD8+ T cells increased the generation, proliferative capacity and cytotoxicity of Tim-3+ cells without altering Slamf6+ numbers during lymphocytic choriomeningitis virus clone 13 infection. Likewise, Ptpn2 deletion in CD8+ T cells enhanced Tim-3+ anti-tumor responses and improved tumor control. Deletion of Ptpn2 throughout the immune system resulted in MC38 tumor clearance and improved programmed cell death-1 checkpoint blockade responses to B16 tumors. Our results indicate that increasing the number of cytotoxic Tim-3+CD8+ T cells can promote effective anti-tumor immunity and implicate PTPN2 in immune cells as an attractive cancer immunotherapy target.
Assuntos
Adenocarcinoma/imunologia , Linfócitos T CD8-Positivos/fisiologia , Neoplasias do Colo/imunologia , Imunoterapia/métodos , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/fisiologia , Células Progenitoras Linfoides/fisiologia , Melanoma/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Neoplasias Cutâneas/imunologia , Animais , Senescência Celular , Citotoxicidade Imunológica , Feminino , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Tolerância Imunológica , Interferon Tipo I/metabolismo , Masculino , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Transdução de Sinais , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismoRESUMO
Immune checkpoint blockade therapy has shifted the paradigm for cancer treatment. However, the majority of patients lack effective responses due to insufficient T cell infiltration in tumors. Here we show that expression of mitochondrial uncoupling protein 2 (UCP2) in tumor cells determines the immunostimulatory feature of the tumor microenvironment (TME) and is positively associated with prolonged survival. UCP2 reprograms the immune state of the TME by altering its cytokine milieu in an interferon regulatory factor 5-dependent manner. Consequently, UCP2 boosts the conventional type 1 dendritic cell- and CD8+ T cell-dependent anti-tumor immune cycle and normalizes the tumor vasculature. Finally we show, using either a genetic or pharmacological approach, that induction of UCP2 sensitizes melanomas to programmed cell death protein-1 blockade treatment and elicits effective anti-tumor responses. Together, this study demonstrates that targeting the UCP2 pathway is a potent strategy for alleviating the immunosuppressive TME and overcoming the primary resistance of programmed cell death protein-1 blockade.
Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Melanoma Experimental/imunologia , Neoplasias Cutâneas/imunologia , Microambiente Tumoral/imunologia , Proteína Desacopladora 2/imunologia , Animais , Antineoplásicos Imunológicos/farmacologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Resistencia a Medicamentos Antineoplásicos/imunologia , Feminino , Humanos , Imunoterapia/métodos , Fatores Reguladores de Interferon/imunologia , Fatores Reguladores de Interferon/metabolismo , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/mortalidade , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Neoplasias Cutâneas/irrigação sanguínea , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/mortalidade , Análise de Sobrevida , Resultado do Tratamento , Proteína Desacopladora 2/genética , Proteína Desacopladora 2/metabolismoRESUMO
Metabolic activity is intimately linked to T cell fate and function. Using high-resolution mass spectrometry, we generated dynamic metabolome and proteome profiles of human primary naive T cells following activation. We discovered critical changes in the arginine metabolism that led to a drop in intracellular L-arginine concentration. Elevating L-arginine levels induced global metabolic changes including a shift from glycolysis to oxidative phosphorylation in activated T cells and promoted the generation of central memory-like cells endowed with higher survival capacity and, in a mouse model, anti-tumor activity. Proteome-wide probing of structural alterations, validated by the analysis of knockout T cell clones, identified three transcriptional regulators (BAZ1B, PSIP1, and TSN) that sensed L-arginine levels and promoted T cell survival. Thus, intracellular L-arginine concentrations directly impact the metabolic fitness and survival capacity of T cells that are crucial for anti-tumor responses.
Assuntos
Arginina/metabolismo , Linfócitos T CD4-Positivos/imunologia , Imunomodulação , Ativação Linfocitária , Melanoma Experimental/imunologia , Neoplasias Cutâneas/imunologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Linfócitos T CD4-Positivos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Técnicas de Inativação de Genes , Glicólise , Humanos , Memória Imunológica , Metaboloma , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação Oxidativa , Proteoma , Fatores de Transcrição/metabolismo , Transcrição GênicaRESUMO
The nature of the anti-tumor immune response changes as primary tumors progress and metastasize. We investigated the role of resident memory (Trm) and circulating memory (Tcirm) cells in anti-tumor responses at metastatic locations using a mouse model of melanoma-associated vitiligo. We found that the transcriptional characteristics of tumor-specific CD8+ T cells were defined by the tissue of occupancy. Parabiosis revealed that tumor-specific Trm and Tcirm compartments persisted throughout visceral organs, but Trm cells dominated lymph nodes (LNs). Single-cell RNA-sequencing profiles of Trm cells in LN and skin were distinct, and T cell clonotypes that occupied both tissues were overwhelmingly maintained as Trm in LNs. Whereas Tcirm cells prevented melanoma growth in the lungs, Trm afforded long-lived protection against melanoma seeding in LNs. Expanded Trm populations were also present in melanoma-involved LNs from patients, and their transcriptional signature predicted better survival. Thus, tumor-specific Trm cells persist in LNs, restricting metastatic cancer.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Linfonodos/imunologia , Melanoma Experimental/imunologia , Melanoma/imunologia , Neoplasias Cutâneas/imunologia , Animais , Humanos , Camundongos , Vitiligo , Melanoma Maligno CutâneoRESUMO
Focal adhesion kinase (FAK) promotes anti-tumor immune evasion. Specifically, the kinase activity of nuclear-targeted FAK in squamous cell carcinoma (SCC) cells drives exhaustion of CD8(+) T cells and recruitment of regulatory T cells (Tregs) in the tumor microenvironment by regulating chemokine/cytokine and ligand-receptor networks, including via transcription of Ccl5, which is crucial. These changes inhibit antigen-primed cytotoxic CD8(+) T cell activity, permitting growth of FAK-expressing tumors. Mechanistically, nuclear FAK is associated with chromatin and exists in complex with transcription factors and their upstream regulators that control Ccl5 expression. Furthermore, FAK's immuno-modulatory nuclear activities may be specific to cancerous squamous epithelial cells, as normal keratinocytes do not have nuclear FAK. Finally, we show that a small-molecule FAK kinase inhibitor, VS-4718, which is currently in clinical development, also drives depletion of Tregs and promotes a CD8(+) T cell-mediated anti-tumor response. Therefore, FAK inhibitors may trigger immune-mediated tumor regression, providing previously unrecognized therapeutic opportunities.
Assuntos
Carcinoma de Células Escamosas/imunologia , Quimiocina CCL5/genética , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Neoplasias Cutâneas/imunologia , Linfócitos T Reguladores/imunologia , Evasão Tumoral , Aminopiridinas/administração & dosagem , Animais , Carcinoma de Células Escamosas/metabolismo , Quimiocina CCL5/imunologia , Modelos Animais de Doenças , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Proteína-Tirosina Quinases de Adesão Focal/genética , Humanos , Queratinócitos/metabolismo , Camundongos , Camundongos Nus , Neoplasias Cutâneas/metabolismo , Transcrição GênicaRESUMO
The primary mechanisms supporting immunoregulatory polarization of myeloid cells upon infiltration into tumors remain largely unexplored. Elucidation of these signals could enable better strategies to restore protective anti-tumor immunity. Here, we investigated the role of the intrinsic activation of the PKR-like endoplasmic reticulum (ER) kinase (PERK) in the immunoinhibitory actions of tumor-associated myeloid-derived suppressor cells (tumor-MDSCs). PERK signaling increased in tumor-MDSCs, and its deletion transformed MDSCs into myeloid cells that activated CD8+ T cell-mediated immunity against cancer. Tumor-MDSCs lacking PERK exhibited disrupted NRF2-driven antioxidant capacity and impaired mitochondrial respiratory homeostasis. Moreover, reduced NRF2 signaling in PERK-deficient MDSCs elicited cytosolic mitochondrial DNA elevation and, consequently, STING-dependent expression of anti-tumor type I interferon. Reactivation of NRF2 signaling, conditional deletion of STING, or blockade of type I interferon receptor I restored the immunoinhibitory potential of PERK-ablated MDSCs. Our findings demonstrate the pivotal role of PERK in tumor-MDSC functionality and unveil strategies to reprogram immunosuppressive myelopoiesis in tumors to boost cancer immunotherapy.
Assuntos
Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Epitelial do Ovário/imunologia , Regulação Neoplásica da Expressão Gênica , Melanoma Experimental/imunologia , Proteínas de Membrana/imunologia , Neoplasias Cutâneas/imunologia , eIF-2 Quinase/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Carcinoma Epitelial do Ovário/patologia , Feminino , Humanos , Terapia de Imunossupressão , Interferon-alfa/genética , Interferon-alfa/imunologia , Interferon beta/genética , Interferon beta/imunologia , Masculino , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/patologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/imunologia , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Resposta a Proteínas não Dobradas/imunologia , eIF-2 Quinase/deficiência , eIF-2 Quinase/genéticaRESUMO
Within the tumour microenvironment, CD4+ T cells can promote or suppress antitumour responses through the recognition of antigens presented by human leukocyte antigen (HLA) class II molecules1,2, but how cancers co-opt these physiologic processes to achieve immune evasion remains incompletely understood. Here we performed in-depth analysis of the phenotype and tumour specificity of CD4+ T cells infiltrating human melanoma specimens, finding that exhausted cytotoxic CD4+ T cells could be directly induced by melanoma cells through recognition of HLA class II-restricted neoantigens, and also HLA class I-restricted tumour-associated antigens. CD4+ T regulatory (TReg) cells could be indirectly elicited through presentation of tumour antigens via antigen-presenting cells. Notably, numerous tumour-reactive CD4+ TReg clones were stimulated directly by HLA class II-positive melanoma and demonstrated specificity for melanoma neoantigens. This phenomenon was observed in the presence of an extremely high tumour neoantigen load, which we confirmed to be associated with HLA class II positivity through the analysis of 116 melanoma specimens. Our data reveal the landscape of infiltrating CD4+ T cells in melanoma and point to the presentation of HLA class II-restricted neoantigens and direct engagement of immunosuppressive CD4+ TReg cells as a mechanism of immune evasion that is favoured in HLA class II-positive melanoma.
Assuntos
Antígenos de Neoplasias , Linfócitos T CD4-Positivos , Melanoma , Neoplasias Cutâneas , Células Apresentadoras de Antígenos , Antígenos de Neoplasias/imunologia , Antígenos HLA , Humanos , Melanoma/imunologia , Fenótipo , Neoplasias Cutâneas/imunologia , Células Tumorais Cultivadas , Microambiente TumoralRESUMO
Tumor-associated eosinophilia is frequently observed in cancer. However, despite numerous studies of patients with cancer and mouse models of cancer, it has remained uncertain if eosinophils contribute to tumor immunity or are mere bystander cells. Here we report that activated eosinophils were essential for tumor rejection in the presence of tumor-specific CD8(+) T cells. Tumor-homing eosinophils secreted chemoattractants that guided T cells into the tumor, which resulted in tumor eradication and survival. Activated eosinophils initiated substantial changes in the tumor microenvironment, including macrophage polarization and normalization of the tumor vasculature, which are known to promote tumor rejection. Thus, our study presents a new concept for eosinophils in cancer that may lead to novel therapeutic strategies.
Assuntos
Vasos Sanguíneos/imunologia , Linfócitos T CD8-Positivos/imunologia , Fatores Quimiotáticos/imunologia , Eosinófilos/imunologia , Melanoma/imunologia , Neoplasias Cutâneas/imunologia , Animais , Diferenciação Celular , Movimento Celular , Citotoxicidade Imunológica , Melanoma/irrigação sanguínea , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Neovascularização Patológica/imunologia , Neovascularização Fisiológica , Neoplasias Cutâneas/irrigação sanguínea , Carga Tumoral/imunologia , Microambiente TumoralRESUMO
The MHC class I antigen presentation system enables T cell immunosurveillance of cancers and viruses. A substantial fraction of the immunopeptidome derives from rapidly degraded nascent polypeptides (DRiPs). By knocking down each of the 80 ribosomal proteins, we identified proteins that modulate peptide generation without altering source protein expression. We show that 60S ribosomal proteins L6 (RPL6) and RPL28, which are adjacent on the ribosome, play opposite roles in generating an influenza A virus-encoded peptide. Depleting RPL6 decreases ubiquitin-dependent peptide presentation, whereas depleting RPL28 increases ubiquitin-dependent and -independent peptide presentation. 40S ribosomal protein S28 (RPS28) knockdown increases total peptide supply in uninfected cells by increasing DRiP synthesis from non-canonical translation of "untranslated" regions and non-AUG start codons and sensitizes tumor cells for T cell targeting. Our findings raise the possibility of modulating immunosurveillance by pharmaceutical targeting ribosomes.
Assuntos
Apresentação de Antígeno , Antígenos de Histocompatibilidade Classe I/biossíntese , Proteínas Ribossômicas/metabolismo , Subunidades Ribossômicas Maiores de Eucariotos/metabolismo , Subunidades Ribossômicas Menores de Eucariotos/metabolismo , Linfócitos T/metabolismo , Animais , Linhagem Celular Tumoral , Técnicas de Cocultura , Células HEK293 , Antígenos de Histocompatibilidade Classe I/imunologia , Interações Hospedeiro-Patógeno , Humanos , Vigilância Imunológica , Vírus da Influenza A/imunologia , Vírus da Influenza A/patogenicidade , Melanoma/imunologia , Melanoma/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Ribossômicas/genética , Subunidades Ribossômicas Maiores de Eucariotos/genética , Subunidades Ribossômicas Menores de Eucariotos/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/metabolismo , Linfócitos T/imunologia , Linfócitos T/virologiaRESUMO
Melanoma, renowned for its aggressive behavior and resistance to conventional treatments, stands as a formidable challenge in the oncology landscape. The dynamic and complex interplay between cancer cells and the tumor microenvironment has gained significant attention, revealing Melanoma-Associated Fibroblasts (MAFs) as central players in disease progression. The heterogeneity of MAFs endows them with a dual role in melanoma. This exhaustive review seeks to not only shed light on the multifaceted roles of MAFs in orchestrating tumor-promoting inflammation but also to explore their involvement in antitumor immunity. By unraveling novel mechanisms underlying MAF functions, this review aims to provide a comprehensive understanding of their impact on melanoma development. Additionally, it delves into the potential of leveraging MAFs for innovative immunotherapeutic strategies, offering new avenues for enhancing treatment outcomes in the challenging realm of melanoma therapeutics.
Assuntos
Fibroblastos Associados a Câncer , Imunoterapia , Melanoma , Microambiente Tumoral , Humanos , Melanoma/imunologia , Melanoma/terapia , Melanoma/patologia , Microambiente Tumoral/imunologia , Imunoterapia/métodos , Fibroblastos Associados a Câncer/imunologia , Fibroblastos Associados a Câncer/metabolismo , Animais , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/terapia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/genética , Inflamação/imunologia , Fibroblastos/imunologia , Fibroblastos/metabolismoRESUMO
While Merkel cell polyomavirus (MCPyV or MCV) is an abundant virus frequently shed from healthy skin, it is one of the most lethal tumor viruses in immunocompromised individuals, highlighting the crucial role of host immunity in controlling MCPyV oncogenic potential. Despite its prevalence, very little is known about how MCPyV interfaces with the host immune response to maintain asymptomatic persistent infection and how inadequate control of MCPyV infection triggers MCC tumorigenesis. In this study, we discovered that the MCPyV protein, known as the Alternative Large Tumor Open Reading Frame (ALTO), also referred to as middle T, effectively primes and activates the STING signaling pathway. It recruits Src kinase into the complex of STING downstream kinase TBK1 to trigger its autophosphorylation, which ultimately activates the subsequent antiviral immune response. Combining single-cell analysis with both loss- and gain-of-function studies of MCPyV infection, we demonstrated that the activity of ALTO leads to a decrease in MCPyV replication. Thus, we have identified ALTO as a crucial viral factor that modulates the STING-TBK1 pathway, creating a negative feedback loop that limits viral infection and maintains a delicate balance with the host immune system. Our study reveals a novel mechanism by which a tumorigenic virus-encoded protein can link Src function in cell proliferation to the activation of innate immune signaling, thereby controlling viral spread, and sustaining persistent infection. Our previous findings suggest that STING also functions as a tumor suppressor in MCPyV-driven oncogenesis. This research provides a foundation for investigating how disruptions in the finely tuned virus-host balance, maintained by STING, could alter the fate of MCPyV infection, potentially encouraging malignancy.
Assuntos
Poliomavírus das Células de Merkel , Infecções por Polyomavirus , Proteínas Serina-Treonina Quinases , Infecções Tumorais por Vírus , Proteínas Serina-Treonina Quinases/metabolismo , Infecções por Polyomavirus/metabolismo , Infecções por Polyomavirus/imunologia , Infecções por Polyomavirus/virologia , Humanos , Infecções Tumorais por Vírus/metabolismo , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/virologia , Carcinoma de Célula de Merkel/virologia , Carcinoma de Célula de Merkel/metabolismo , Proteínas de Membrana/metabolismo , Transdução de Sinais , Proteínas Virais/metabolismo , Replicação Viral , Neoplasias Cutâneas/virologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/imunologia , AnimaisRESUMO
Somatic mutations in cancer can be translated into peptides, termed neoantigens, which can be recognized by the immune system as "foreign" epitopes. Two recent studies in Nature (Sahin et al., 2017; Ott et al., 2017) examine the effects of neoantigen vaccines on patients with stage III or IV melanoma and demonstrate immunogenicity and intriguing clinical safety and efficacy data in phase I studies.
Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Imunoterapia/métodos , Melanoma/terapia , Neoplasias Cutâneas/terapia , Animais , Antígenos de Neoplasias/genética , Autoantígenos/genética , Ensaios Clínicos Fase I como Assunto , Humanos , Melanoma/imunologia , Melanoma/patologia , Mutação/genética , Metástase Neoplásica , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Vacinas de Subunidades AntigênicasRESUMO
Ten-Eleven-Translocation-2 (Tet2) is a DNA methylcytosine dioxygenase that functions as a tumor suppressor in hematopoietic malignancies. We examined the role of Tet2 in tumor-tissue myeloid cells and found that Tet2 sustains the immunosuppressive function of these cells. We found that Tet2 expression is increased in intratumoral myeloid cells both in mouse models of melanoma and in melanoma patients and that this increased expression is dependent on an IL-1R-MyD88 pathway. Ablation of Tet2 in myeloid cells suppressed melanoma growth in vivo and shifted the immunosuppressive gene expression program in tumor-associated macrophages to a proinflammatory one, with a concomitant reduction of the immunosuppressive function. This resulted in increased numbers of effector T cells in the tumor, and T cell depletion abolished the reduced tumor growth observed upon myeloid-specific deletion of Tet2. Our findings reveal a non-cell-intrinsic, tumor-promoting function for Tet2 and suggest that Tet2 may present a therapeutic target for the treatment of non-hematologic malignancies.