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1.
Immunity ; 53(3): 564-580.e9, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32750334

RESUMO

Tumor immune escape limits durable responses to T cell therapy. Here, we examined how regulation and function of gene products that provide the target epitopes for CD8+ T cell anti-tumor immunity influence therapeutic efficacy and resistance. We used a CRISPR-Cas9-based method (CRISPitope) in syngeneic melanoma models to fuse the same model CD8+ T cell epitope to the C-termini of different endogenous gene products. Targeting melanosomal proteins or oncogenic CDK4R24C (Cyclin-dependent kinase 4) by adoptive cell transfer (ACT) of the same epitope-specific CD8+ T cells revealed diverse genetic and non-genetic immune escape mechanisms. ACT directed against melanosomal proteins, but not CDK4R24C, promoted melanoma dedifferentiation, and increased myeloid cell infiltration. CDK4R24C antigen persistence was associated with an interferon-high and T-cell-rich tumor microenvironment, allowing for immune checkpoint inhibition as salvage therapy. Thus, the choice of target antigen determines the phenotype and immune contexture of recurrent melanomas, with implications to the design of cancer immunotherapies.


Assuntos
Transferência Adotiva/métodos , Linfócitos T CD8-Positivos/transplante , Epitopos de Linfócito T/imunologia , Melanoma/imunologia , Melanoma/terapia , Evasão Tumoral/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Terapia Baseada em Transplante de Células e Tecidos/métodos , Epitopos de Linfócito T/genética , Técnicas de Inativação de Genes , Inibidores de Checkpoint Imunológico/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/citologia , Células Mieloides/imunologia , Microambiente Tumoral/imunologia
2.
Mol Cell ; 77(1): 120-137.e9, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31733993

RESUMO

Phenotypic and metabolic heterogeneity within tumors is a major barrier to effective cancer therapy. How metabolism is implicated in specific phenotypes and whether lineage-restricted mechanisms control key metabolic vulnerabilities remain poorly understood. In melanoma, downregulation of the lineage addiction oncogene microphthalmia-associated transcription factor (MITF) is a hallmark of the proliferative-to-invasive phenotype switch, although how MITF promotes proliferation and suppresses invasion is poorly defined. Here, we show that MITF is a lineage-restricted activator of the key lipogenic enzyme stearoyl-CoA desaturase (SCD) and that SCD is required for MITFHigh melanoma cell proliferation. By contrast MITFLow cells are insensitive to SCD inhibition. Significantly, the MITF-SCD axis suppresses metastasis, inflammatory signaling, and an ATF4-mediated feedback loop that maintains de-differentiation. Our results reveal that MITF is a lineage-specific regulator of metabolic reprogramming, whereby fatty acid composition is a driver of melanoma phenotype switching, and highlight that cell phenotype dictates the response to drugs targeting lipid metabolism.


Assuntos
Adaptação Fisiológica/fisiologia , Ácidos Graxos/metabolismo , Melanoma/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Estearoil-CoA Dessaturase/metabolismo , Animais , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Regulação para Baixo/fisiologia , Humanos , Camundongos , Invasividade Neoplásica/patologia , Fenótipo , Transdução de Sinais/fisiologia
3.
Immunity ; 47(6): 1007-1009, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29262340

RESUMO

Mutant RAS is a major oncoprotein in human cancer and PD-L1 is a key driver of cancer immune evasion. In this issue of Immunity, Coelho et al. (2017) demonstrate that oncogenic RAS signaling promotes tumor immune escape by stabilizing PD-L1 mRNA.


Assuntos
Antígeno B7-H1 , Neoplasias , Humanos , Evasão da Resposta Imune , RNA Mensageiro , Evasão Tumoral
4.
Immunity ; 47(4): 789-802.e9, 2017 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-29045907

RESUMO

Inhibitors of the receptor tyrosine kinase c-MET are currently used in the clinic to target oncogenic signaling in tumor cells. We found that concomitant c-MET inhibition promoted adoptive T cell transfer and checkpoint immunotherapies in murine cancer models by increasing effector T cell infiltration in tumors. This therapeutic effect was independent of tumor cell-intrinsic c-MET dependence. Mechanistically, c-MET inhibition impaired the reactive mobilization and recruitment of neutrophils into tumors and draining lymph nodes in response to cytotoxic immunotherapies. In the absence of c-MET inhibition, neutrophils recruited to T cell-inflamed microenvironments rapidly acquired immunosuppressive properties, restraining T cell expansion and effector functions. In cancer patients, high serum levels of the c-MET ligand HGF correlated with increasing neutrophil counts and poor responses to checkpoint blockade therapies. Our findings reveal a role for the HGF/c-MET pathway in neutrophil recruitment and function and suggest that c-MET inhibitor co-treatment may improve responses to cancer immunotherapy in settings beyond c-MET-dependent tumors.


Assuntos
Imunoterapia/métodos , Neoplasias Experimentais/terapia , Neutrófilos/imunologia , Proteínas Proto-Oncogênicas c-met/imunologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/imunologia , Interferon gama/imunologia , Interferon gama/metabolismo , Estimativa de Kaplan-Meier , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/metabolismo , Neutrófilos/metabolismo , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
5.
Semin Cancer Biol ; 86(Pt 2): 477-490, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35752398

RESUMO

Immune checkpoint inhibitors (ICIs) have demonstrated impressive antitumor activity in patients with advanced and early stage melanoma, thus improving long-term survival outcomes. However, most patients derive limited benefit from immunotherapy, due to the development of primary, adaptive, or acquired resistance mechanisms. Immunotherapy resistance is a complex phenomenon that depends on genetic and epigenetic mechanisms which, in turn, drive the interplay between cancer cells and the tumor microenvironment (TME). Immunologically "cold" (i.e. non-inflamed) tumors lack or have few tumor infiltrating lymphocytes (TILs) as a result of low tumor mutational burden (TMB), defective antigen presentation, or physical barriers to lymphocyte migration, resulting in a minimal benefit from immunotherapy. In contrast, in most cases immunologically "hot" (i.e. inflamed) tumors display high TMB, implying a higher load of neoantigens and increased programmed cell death ligand 1 (PD-L1) expression, with a consequently higher rate of TILs. However, the presence of TILs does not necessarily denote the tumor as immunologically "hot", since the presence of tumor-specific CD8+ T cells persistently exposed to antigenic stimulation induces a dysfunctional state called "exhaustion", which leads to a reduced response to immunotherapy. In recent years, efforts have been made to characterize mechanisms of resistance to immunotherapy, and to investigate strategies to overcome treatment resistance. Indeed, predictors of response and toxicity to immunotherapy are still lacking and, to date, there are no reliable predictive biomarkers to select patients according to baseline clinical, histological, or genomic characteristics. In this review, we will focus on the morphologic and immunohistochemical characteristics of the TME, and on the molecular determinants of resistance to immunotherapy, differentiating between inflamed and non-inflamed melanomas. Then, we will provide a thorough overview of preclinical data on genetic and epigenetic mechanisms with a potential impact on the immune response and patient outcome. Finally, we will focus our attention on the role of potential biomarkers in determining disease response to immunotherapy, in the adjuvant and metastatic setting, providing an insight into current and future research in this field.


Assuntos
Linfócitos T CD8-Positivos , Melanoma , Humanos , Imunoterapia/métodos , Linfócitos do Interstício Tumoral , Microambiente Tumoral/genética , Melanoma/genética , Melanoma/terapia , Biomarcadores Tumorais , Fatores Imunológicos
6.
Nature ; 507(7490): 109-13, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24572365

RESUMO

Intermittent intense ultraviolet (UV) exposure represents an important aetiological factor in the development of malignant melanoma. The ability of UV radiation to cause tumour-initiating DNA mutations in melanocytes is now firmly established, but how the microenvironmental effects of UV radiation influence melanoma pathogenesis is not fully understood. Here we report that repetitive UV exposure of primary cutaneous melanomas in a genetically engineered mouse model promotes metastatic progression, independent of its tumour-initiating effects. UV irradiation enhanced the expansion of tumour cells along abluminal blood vessel surfaces and increased the number of lung metastases. This effect depended on the recruitment and activation of neutrophils, initiated by the release of high mobility group box 1 (HMGB1) from UV-damaged epidermal keratinocytes and driven by Toll-like receptor 4 (TLR4). The UV-induced neutrophilic inflammatory response stimulated angiogenesis and promoted the ability of melanoma cells to migrate towards endothelial cells and use selective motility cues on their surfaces. Our results not only reveal how UV irradiation of epidermal keratinocytes is sensed by the innate immune system, but also show that the resulting inflammatory response catalyses reciprocal melanoma-endothelial cell interactions leading to perivascular invasion, a phenomenon originally described as angiotropism in human melanomas by histopathologists. Angiotropism represents a hitherto underappreciated mechanism of metastasis that also increases the likelihood of intravasation and haematogenous dissemination. Consistent with our findings, ulcerated primary human melanomas with abundant neutrophils and reactive angiogenesis frequently show angiotropism and a high risk for metastases. Our work indicates that targeting the inflammation-induced phenotypic plasticity of melanoma cells and their association with endothelial cells represent rational strategies to specifically interfere with metastatic progression.


Assuntos
Inflamação/etiologia , Neoplasias Pulmonares/secundário , Melanoma/irrigação sanguínea , Melanoma/patologia , Neoplasias Cutâneas/patologia , Queimadura Solar/etiologia , Raios Ultravioleta , Animais , Movimento Celular/efeitos da radiação , Transformação Celular Neoplásica/efeitos da radiação , Modelos Animais de Doenças , Progressão da Doença , Feminino , Proteína HMGB1/metabolismo , Imunidade Inata/efeitos da radiação , Queratinócitos/metabolismo , Queratinócitos/patologia , Queratinócitos/efeitos da radiação , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/etiologia , Masculino , Melanócitos/patologia , Melanócitos/efeitos da radiação , Melanoma/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/etiologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neoplasias Cutâneas/irrigação sanguínea , Neoplasias Cutâneas/etiologia , Queimadura Solar/complicações , Receptor 4 Toll-Like/metabolismo
7.
J Immunol ; 190(10): 4929-36, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23585676

RESUMO

Epidermal keratinocytes (KCs) and cannabinoid (CB) receptors both participate in the regulation of inflammatory responses in a mouse model for allergic contact dermatitis, the contact hypersensitivity (CHS) response to the obligate sensitizer 2,4-dinitrofluorobenzene. In this study, we investigated the cellular and molecular mechanisms how CB1 receptors attenuate CHS responses to 2,4-dinitrofluorobenzene. We used a conditional gene-targeting approach to identify the relative contribution of CB1 receptors on epidermal KCs for the control of CHS responses. To determine the underlying cellular and molecular mechanisms that regulate inflammatory responses in the effector phase of CHS, we performed further investigations on inflamed ear tissue and primary KC cultures using morphologic, molecular, and immunologic methods. Mice with a KC-specific deletion of CB1 receptors developed increased and prolonged CHS responses. These were associated with enhanced reactive epidermal acanthosis and inflammatory KC hyperproliferation in the effector phase of CHS. In vitro, primary cultures of CB1 receptor-deficient KC released increased amounts of CXCL10 and CCL8 after stimulation with IFN-γ compared with controls. In vivo, contact allergic ear tissue of CB1 receptor-deficient KCs showed enhanced expression of CXCL10 and CCL8 compared with controls. Further investigations established CCL8 as a proinflammatory chemokine regulated by CB1 receptors that promotes immune cell recruitment to allergen-challenged skin. Taken together, these results demonstrate that CB1 receptors are functionally expressed by KCs in vivo and help to limit the secretion of proinflammatory chemokines that regulate T cell-dependent inflammation in the effector phase of CHS.


Assuntos
Quimiocina CCL8/metabolismo , Quimiocina CXCL10/metabolismo , Dermatite Alérgica de Contato/imunologia , Queratinócitos/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Transferência Adotiva , Animais , Proliferação de Células , Células Cultivadas , Dermatite Alérgica de Contato/metabolismo , Dinitrofluorbenzeno , Orelha , Inflamação/imunologia , Interferon gama/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
8.
Exp Dermatol ; 23(6): 401-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24750433

RESUMO

Atopic dermatitis is a chronic inflammatory disease characterized by an impaired epidermal barrier function combined with a chronic Th2-type inflammatory response and an intense pruritus. Here, we used an experimental mouse model for Th2-type contact hypersensitivity (CHS) to fluorescein isothiocyanate (FITC) to investigate the potential role of cannabinoid 1 receptors (CB1) in the pathophysiology of mouse atopic-like dermatitis. Mice lacking CB1 receptors globally (Cnr1(-/-) ) or specifically in keratinocytes (KC-Cnr1(-/-) ) as well as wild-type (WT) control mice were sensitized and challenged with FITC. We examined ear swelling responses, transepidermal water loss, Th2-type skin inflammatory responses and serum IgE levels. Both Cnr1(-/-) and KC-Cnr1(-/-) showed enhanced CHS responses to FITC and a delayed epidermal barrier repair when compared with WT mice. mRNA levels for IL-4, thymic stromal lymphopoietin (TSLP) and CCL8, as well as eosinophil activity, were significantly increased in inflamed ear tissue of FITC-challenged Cnr1(-/-) and KC-Cnr1(-/-) mice. Importantly, CB1 receptor-deficient keratinocytes secreted increased levels of TSLP, a proinflammatory mediator that drives Th2-type skin inflammation in atopic dermatitis, under basal and Th2-type inflammatory conditions. Taken together, our results demonstrate that CB1 receptors in keratinocytes help to maintain epidermal barrier homoeostasis and attenuate Th2-type allergic inflammatory responses. Based on our work, we propose that enhanced epidermal allergen penetrance cooperates with increased production of TSLP and CCL8 by epidermal keratinocytes for the induction of type 2 CD4+ T helper cells. Our results place keratinocytes at the cross-roads of outside-in and inside-out pathophysiologic mechanisms of atopic dermatitis.


Assuntos
Dermatite Atópica/metabolismo , Dermatite Atópica/prevenção & controle , Queratinócitos/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Animais , Células Cultivadas , Quimiocina CCL8/metabolismo , Citocinas/metabolismo , Dermatite Atópica/induzido quimicamente , Modelos Animais de Doenças , Fluoresceína-5-Isotiocianato/efeitos adversos , Homeostase/fisiologia , Interleucina-4/metabolismo , Queratinócitos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor CB1 de Canabinoide/deficiência , Receptor CB1 de Canabinoide/genética , Células Th2/patologia , Linfopoietina do Estroma do Timo
10.
Biomark Res ; 11(1): 56, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37259155

RESUMO

BACKGROUND: Inducible T cell costimulator ICOS is an emerging target in immuno-oncology. The aim of this study was to investigate the epigenetic regulation of ICOS in melanoma by DNA methylation. METHODS: We comprehensively investigate ICOS DNA methylation of specific CpG sites and expression pattern within the melanoma microenvironment with regard to immune correlates, differentiation, clinical outcomes, and immune checkpoint blockade (ICB) response. RESULTS: Our study revealed a sequence-contextual CpG methylation pattern consistent with an epigenetically regulated gene. We found a cell type-specific methylation pattern and locus-specific correlations and associations of CpG methylation with ICOS mRNA expression, immune infiltration, melanoma differentiation, prognosis, and response to ICB. High ICOS mRNA expression was identified as a surrogate for enriched immune cell infiltration and was associated with favorable overall survival (OS) in non-ICB-treated patients and predicted response and a prolonged progression-free survival (PFS) following ICB therapy initiation. ICOS hypomethylation, however, significantly correlated with poor OS in non-ICB patients but predicted higher response and prolonged PFS and OS in ICB-treated patients. Moreover, we observed cytoplasmic and sporadically nuclear tumor cell-intrinsic ICOS protein expression. Tumor cell-intrinsic ICOS protein and mRNA expression was inducible by pharmacological demethylation with decitabine. CONCLUSION: Our study identified ICOS DNA methylation and mRNA expression as promising prognostic and predictive biomarkers for immunotherapy in melanoma and points towards a hitherto undescribed role of ICOS in tumor cells.

11.
J Immunother Cancer ; 11(4)2023 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-37028818

RESUMO

BACKGROUND: Immune responses against tumors are subject to negative feedback regulation. Immune checkpoint inhibitors (ICIs) blocking Programmed cell death protein 1 (PD-1), a receptor expressed on T cells, or its ligand PD-L1 have significantly improved the treatment of cancer, in particular malignant melanoma. Nevertheless, responses and durability are variables, suggesting that additional critical negative feedback mechanisms exist and need to be targeted to improve therapeutic efficacy. METHODS: We used different syngeneic melanoma mouse models and performed PD-1 blockade to identify novel mechanisms of negative immune regulation. Genetic gain-of-function and loss-of-function approaches as well as small molecule inhibitor applications were used for target validation in our melanoma models. We analyzed mouse melanoma tissues from treated and untreated mice by RNA-seq, immunofluorescence and flow cytometry to detect changes in pathway activities and immune cell composition of the tumor microenvironment. We analyzed tissue sections of patients with melanoma by immunohistochemistry as well as publicly available single-cell RNA-seq data and correlated target expression with clinical responses to ICIs. RESULTS: Here, we identified 11-beta-hydroxysteroid dehydrogenase-1 (HSD11B1), an enzyme that converts inert glucocorticoids into active forms in tissues, as negative feedback mechanism in response to T cell immunotherapies. Glucocorticoids are potent suppressors of immune responses. HSD11B1 was expressed in different cellular compartments of melanomas, most notably myeloid cells but also T cells and melanoma cells. Enforced expression of HSD11B1 in mouse melanomas limited the efficacy of PD-1 blockade, whereas small molecule HSD11B1 inhibitors improved responses in a CD8+ T cell-dependent manner. Mechanistically, HSD11B1 inhibition in combination with PD-1 blockade augmented the production of interferon-γ by T cells. Interferon pathway activation correlated with sensitivity to PD-1 blockade linked to anti-proliferative effects on melanoma cells. Furthermore, high levels of HSD11B1, predominantly expressed by tumor-associated macrophages, were associated with poor responses to ICI therapy in two independent cohorts of patients with advanced melanomas analyzed by different methods (scRNA-seq, immunohistochemistry). CONCLUSION: As HSD11B1 inhibitors are in the focus of drug development for metabolic diseases, our data suggest a drug repurposing strategy combining HSD11B1 inhibitors with ICIs to improve melanoma immunotherapy. Furthermore, our work also delineated potential caveats emphasizing the need for careful patient stratification.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1 , Glucocorticoides , Imunoterapia , Melanoma , Animais , Camundongos , Linfócitos T CD8-Positivos , Glucocorticoides/uso terapêutico , Interferon gama/metabolismo , Melanoma/tratamento farmacológico , Melanoma/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Microambiente Tumoral , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Reposicionamento de Medicamentos
12.
STAR Protoc ; 3(1): 101038, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35059651

RESUMO

This protocol details the procedure for CRISPR-assisted insertion of epitopes (CRISPitope), a flexible approach for generating tumor cells expressing model CD8+ T cell epitopes fused to endogenously encoded gene products of choice. CRISPitope-engineered tumor cells can be recognized by T cell receptor-transgenic (TCRtg) CD8+ T cells that are widely used in immunology research. Using mice inoculated with CRISPitope-engineered tumor cells, researchers can investigate how the choice of the target antigen for T cell immunotherapies influences treatment efficacy and resistance mechanisms. For complete details on the use and execution of this protocol, please refer to Effern et al. (2020).


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Animais , Modelos Animais de Doenças , Epitopos de Linfócito T , Imunoterapia Adotiva/métodos , Camundongos , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/genética
13.
Clin Transl Immunology ; 10(4): e1276, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968406

RESUMO

OBJECTIVES: Type I interferons are evolutionally conserved cytokines, with broad antimicrobial and immunoregulatory functions. Despite well-characterised role in spontaneous cancer immunosurveillance, the function of type I IFNs in cancer immunotherapy remains incompletely understood. METHODS: We utilised genetic mouse models to explore the role of the type I IFN system in CD8+ T-cell immunotherapy targeting the melanocytic lineage antigen gp100. RESULTS: The therapeutic efficacy of adoptively transferred T cells was found to depend on a functional type I IFN system in myeloid immune cells. Compromised type I IFN signalling in myeloid immune cells did not prevent expansion, tumor infiltration or effector function of melanoma-specific Pmel-1 CD8+ T cells. However, melanomas growing in globally (Ifnar1-/-) or conditionally (Ifnar1ΔLysM) type I IFN system-deficient mice displayed increased myeloid infiltration, hypoxia and melanoma cell dedifferentiation. Mechanistically, hypoxia was found to induce dedifferentiation and loss of the gp100 target antigen in melanoma cells and type I IFN could directly inhibit the inflammatory activation of myeloid cells. Unexpectedly, the immunotherapy induced significant reduction in tumor blood vessel density and whereas host type I IFN system was not required for the vasculosculpting, it promoted vessel permeability. CONCLUSION: Our results substantiate a complex and plastic phenotypic interconnection between melanoma and myeloid cells in the context of T-cell immunotherapy. Type I IFN signalling in myeloid cells was identified as a key regulator of the balance between antitumor immunity and disease-promoting inflammation, thus supporting the development of novel combinatorial immunotherapies targeting this immune cell compartment.

14.
Cancer Res ; 77(17): 4697-4709, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28652246

RESUMO

Evolution of tumor cell phenotypes promotes heterogeneity and therapy resistance. Here we found that induction of CD73, the enzyme that generates immunosuppressive adenosine, is linked to melanoma phenotype switching. Activating MAPK mutations and growth factors drove CD73 expression, which marked both nascent and full activation of a mesenchymal-like melanoma cell state program. Proinflammatory cytokines like TNFα cooperated with MAPK signaling through the c-Jun/AP-1 transcription factor complex to activate CD73 transcription by binding to an intronic enhancer. In a mouse model of T-cell immunotherapy, CD73 was induced in relapse melanomas, which acquired a mesenchymal-like phenotype. We also detected CD73 upregulation in melanoma patients progressing under adoptive T-cell transfer or immune checkpoint blockade, arguing for an adaptive resistance mechanism. Our work substantiates CD73 as a target to combine with current immunotherapies, but its dynamic regulation suggests limited value of CD73 pretreatment expression as a biomarker to stratify melanoma patients. Cancer Res; 77(17); 4697-709. ©2017 AACR.


Assuntos
5'-Nucleotidase/metabolismo , Regulação Neoplásica da Expressão Gênica , Imunoterapia , Inflamação/complicações , Melanoma/patologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Linfócitos T/transplante , Adenosina/metabolismo , Transferência Adotiva , Animais , Proteínas Ligadas por GPI/metabolismo , Humanos , Inflamação/patologia , Melanoma/imunologia , Melanoma/metabolismo , Melanoma/terapia , Camundongos , Camundongos Endogâmicos C57BL , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Fator de Transcrição AP-1/metabolismo , Células Tumorais Cultivadas
15.
Cancer Res ; 76(2): 251-63, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26511633

RESUMO

Human melanomas exhibit considerable genetic, pathologic, and microenvironmental heterogeneity. Genetically engineered mice have successfully been used to model the genomic aberrations contributing to melanoma pathogenesis, but their ability to recapitulate the phenotypic variability of human disease and the complex interactions with the immune system have not been addressed. Here, we report the unexpected finding that immune cell-poor pigmented and immune cell-rich amelanotic melanomas developed simultaneously in Cdk4R24C-mutant mice upon melanocyte-specific conditional activation of oncogenic BrafV600E and a single application of the carcinogen 7,12-dimethylbenz(a)anthracene. Interestingly, amelanotic melanomas showed morphologic and molecular features of malignant peripheral nerve sheath tumors (MPNST). A bioinformatic cross-species comparison using a gene expression signature of MPNST-like mouse melanomas identified a subset of human melanomas with a similar histomorphology. Furthermore, this subset of human melanomas was found to be highly associated with a mast cell gene signature, and accordingly, mouse MPNST-like melanomas were also extensively infiltrated by mast cells and expressed mast cell chemoattractants similar to human counterparts. A transplantable mouse MPNST-like melanoma cell line recapitulated mast cell recruitment in syngeneic mice, demonstrating that this cell state can directly reconstitute the histomorphologic and microenvironmental features of primary MPNST-like melanomas. Our study emphasizes the importance of reciprocal, phenotype-dependent melanoma-immune cell interactions and highlights a critical role for mast cells in a subset of melanomas. Moreover, our BrafV600E-Cdk4R24C model represents an attractive system for the development of therapeutic approaches that can target the heterogeneous tumor microenvironment characteristic of human melanomas.


Assuntos
Mastócitos/metabolismo , Melanoma/metabolismo , Neoplasias de Bainha Neural/metabolismo , Neoplasias do Sistema Nervoso Periférico/metabolismo , Animais , Linhagem Celular Tumoral , Estudos de Coortes , Expressão Gênica , Humanos , Melanoma/patologia , Camundongos , Análise em Microsséries , Neoplasias de Bainha Neural/patologia , Neoplasias do Sistema Nervoso Periférico/genética , Neoplasias do Sistema Nervoso Periférico/patologia
16.
Life Sci ; 138: 35-40, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25921771

RESUMO

AIM: Cannabinoids (CB) like ∆(9)-tetrahydrocannabinol (THC) can induce cancer cell apoptosis and inhibit angiogenesis. However, the use of cannabinoids for the treatment of malignant diseases is discussed controversially because of their immunomodulatory effects which can suppress anti-tumor immunity. Here we investigated the role of exogenous and endogenous cannabinoids in mouse skin cancer. MAIN METHODS: First we examined the effect of THC, which binds to CB receptors (CB1, CB2), on the growth of the mouse melanoma cell lines B16 and HCmel12 in vitro and in vivo in wild type (WT) and CB1/CB2-receptor deficient mice (Cnr1/2(-/-)). Next we evaluated the role of the endogenous cannabinoid system by studying the growth of chemically induced melanomas, fibrosarcoma and papillomas in WT and Cnr1/2(-/-) mice. KEY FINDINGS: THC significantly inhibited tumor growth of transplanted HCmel12 melanomas in a CB receptor-dependent manner in vivo through antagonistic effects on its characteristic pro-inflammatory microenvironment. Chemically induced skin tumors developed in a similar manner in Cnr1/2(-/-) mice when compared to WT mice. SIGNIFICANCE: Our results confirm the value of exogenous cannabinoids for the treatment of melanoma but do not support a role for the endogenous cannabinoid system in the pathogenesis of skin cancer.


Assuntos
Canabinoides/farmacologia , Neoplasias Cutâneas/patologia , Animais , Linhagem Celular Tumoral , Dronabinol/farmacologia , Fibrossarcoma/patologia , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transplante de Neoplasias , Papiloma/patologia , Receptor CB1 de Canabinoide/genética , Receptor CB2 de Canabinoide/genética , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/etiologia
17.
J Invest Dermatol ; 134(8): 2131-2137, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24577407

RESUMO

ß-Arrestins participate in G-protein receptor signaling and act as adapter proteins that direct the recruitment, activation, and scaffolding of various cytoplasmic signaling complexes. ß-Arrestin 2-deficient (Arrb2(-/-)) mice show decreased T-cell recruitment into allergic lung tissue but increased neutrophil infiltration into wounded skin. Given these opposing effects in different immune cell subsets, we investigated the role of ß-arrestin 2 in the regulation of contact hypersensitivity responses. We observed significantly increased allergic ear swelling to the obligate contact sensitizers DNFB and FITC in Arrb2(-/-) compared with wild-type mice. Immunohistological analyses revealed strikingly increased neutrophil infiltration with abundant subcorneal pustules in inflamed ear tissue of DNFB-allergic Arrb2(-/-) mice. Experiments involving adoptive transfers of sensitized lymphocytes and bone marrow chimeric mice indicated that ß-arrestin 2 exerts its anti-inflammatory effects predominantly through radioresistant, skin-resident cells in the challenge phase of contact hypersensitivity. As a potential mechanism, we found that primary cultures of ß-arrestin 2-deficient keratinocytes secreted higher levels of neutrophil-attracting chemokines including CXCL1/KC in response to T cell-derived cytokines in vitro. These experimental results support a model in which ß-arrestin 2 inhibits the production of proinflammatory chemokines, which limits the recruitment of myeloid immune cells and thereby attenuates allergic skin inflammation.


Assuntos
Arrestinas/fisiologia , Quimiocinas/biossíntese , Dermatite Alérgica de Contato/imunologia , Animais , Quimiocina CXCL2/biossíntese , Dermatite Alérgica de Contato/prevenção & controle , Dinitrofluorbenzeno , Queratinócitos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/fisiologia , Tolerância a Radiação , beta-Arrestina 2 , beta-Arrestinas
18.
Cancer Discov ; 4(6): 674-87, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24589924

RESUMO

UNLABELLED: Infiltration of human melanomas with cytotoxic immune cells correlates with spontaneous type I IFN activation and a favorable prognosis. Therapeutic blockade of immune-inhibitory receptors in patients with preexisting lymphocytic infiltrates prolongs survival, but new complementary strategies are needed to activate cellular antitumor immunity in immune cell-poor melanomas. Here, we show that primary melanomas in Hgf-Cdk4(R24C) mice, which imitate human immune cell-poor melanomas with a poor outcome, escape IFN-induced immune surveillance and editing. Peritumoral injections of immunostimulatory RNA initiated a cytotoxic inflammatory response in the tumor microenvironment and significantly impaired tumor growth. This critically required the coordinated induction of type I IFN responses by dendritic, myeloid, natural killer, and T cells. Importantly, antibody-mediated blockade of the IFN-induced immune-inhibitory interaction between PD-L1 and PD-1 receptors further prolonged the survival. These results highlight important interconnections between type I IFNs and immune-inhibitory receptors in melanoma pathogenesis, which serve as targets for combination immunotherapies. SIGNIFICANCE: Using a genetically engineered mouse melanoma model, we demonstrate that targeted activation of the type I IFN system with immunostimulatory RNA in combination with blockade of immune-inhibitory receptors is a rational strategy to expose immune cell-poor tumors to cellular immune surveillance.


Assuntos
Interferon Tipo I/imunologia , Melanoma Experimental/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , 9,10-Dimetil-1,2-benzantraceno , Animais , Antígeno B7-H1/imunologia , Carcinógenos , Imunoglobulina G/administração & dosagem , Fatores Imunológicos/administração & dosagem , Melanoma Experimental/imunologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Poli I-C/administração & dosagem , Receptor de Morte Celular Programada 1/imunologia , RNA/administração & dosagem , Microambiente Tumoral/imunologia
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