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1.
Cell ; 184(5): 1262-1280.e22, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33636129

RESUMO

Improving effector activity of antigen-specific T cells is a major goal in cancer immunotherapy. Despite the identification of several effector T cell (TEFF)-driving transcription factors (TFs), the transcriptional coordination of TEFF biology remains poorly understood. We developed an in vivo T cell CRISPR screening platform and identified a key mechanism restraining TEFF biology through the ETS family TF, Fli1. Genetic deletion of Fli1 enhanced TEFF responses without compromising memory or exhaustion precursors. Fli1 restrained TEFF lineage differentiation by binding to cis-regulatory elements of effector-associated genes. Loss of Fli1 increased chromatin accessibility at ETS:RUNX motifs, allowing more efficient Runx3-driven TEFF biology. CD8+ T cells lacking Fli1 provided substantially better protection against multiple infections and tumors. These data indicate that Fli1 safeguards the developing CD8+ T cell transcriptional landscape from excessive ETS:RUNX-driven TEFF cell differentiation. Moreover, genetic deletion of Fli1 improves TEFF differentiation and protective immunity in infections and cancer.

2.
Sci Immunol ; 6(55)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452106

RESUMO

The developmental origins of memory T cells remain incompletely understood. During the expansion phase of acute viral infection, we identified a distinct subset of virus-specific CD8+ T cells that possessed distinct characteristics including expression of CD62L, T cell factor 1 (TCF-1), and Eomesodermin; relative quiescence; expression of activation markers; and features of limited effector differentiation. These cells were a quantitatively minor subpopulation of the TCF-1+ pool and exhibited self-renewal, heightened DNA damage surveillance activity, and preferential long-term recall capacity. Despite features of memory and somewhat restrained proliferation during the expansion phase, this subset displayed evidence of stronger TCR signaling than other responding CD8+ T cells, coupled with elevated expression of multiple inhibitory receptors including programmed cell death 1 (PD-1), lymphocyte activating gene 3 (LAG-3), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), CD5, and CD160. Genetic ablation of PD-1 and LAG-3 compromised the formation of this CD62Lhi TCF-1+ subset and subsequent CD8+ T cell memory. Although central memory phenotype CD8+ T cells were formed in the absence of these cells, subsequent memory CD8+ T cell recall responses were compromised. Together, these results identify an important link between genome integrity maintenance and CD8+ T cell memory. Moreover, the data indicate a role for inhibitory receptors in preserving key memory CD8+ T cell precursors during initial activation and differentiation. Identification of this rare subpopulation within the memory CD8+ T cell precursor pool may help reconcile models of the developmental origin of long-term CD8+ T cell memory.

3.
Front Immunol ; 11: 1633, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849557

RESUMO

The clinical success of cancer immunotherapies targeting PD-1 and CTLA-4 has ignited a substantial research effort to improve our understanding of tumor immunity. Recent studies have revealed that the immune contexture of a tumor influences therapeutic response and survival benefit for cancer patients. Identifying treatment modalities that limit immunosuppression, relieve T cell exhaustion, and potentiate effector functions in the tumor microenvironment (TME) is of much interest. In particular, combinatorial therapeutic approaches that re-educate the TME by limiting the accumulation of immunosuppressive immune cells, such as Foxp3 regulatory T cells (Tregs) and tumor-associated macrophages (TAMs), while promoting CD8+ and CD4+ effector T cell activity is critical. Here, we review key approaches to target these immunosuppressive immune cell subsets and signaling molecules and define the impact of these changes to the tumor milieu. We will highlight the preclinical and clinical evidence for their ability to improve anti-tumor immune responses as well as strategies and challenges for their implementation. Together, this review will provide understanding of therapeutic approaches to efficiently shape the TME and reinvigorate the immune response against cancer.

4.
Cell Rep ; 31(13): 107827, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32610128

RESUMO

The PD-1 pathway regulates dysfunctional T cells in chronic infection and cancer, but the role of this pathway during acute infection remains less clear. Here, we demonstrate that PD-1 signals are needed for optimal memory. Mice deficient in the PD-1 pathway exhibit impaired CD8+ T cell memory following acute influenza infection, including reduced virus-specific CD8+ T cell numbers and compromised recall responses. PD-1 blockade during priming leads to similar differences early post-infection but without the defect in memory formation, suggesting that timing and/or duration of PD-1 blockade could be tailored to modulate host responses. Our studies reveal a role for PD-1 as an integrator of CD8+ T cell signals that promotes CD8+ T cell memory formation and suggest PD-1 continues to fine-tune CD8+ T cells after they migrate into non-lymphoid tissues. These findings have important implications for PD-1-based immunotherapy, in which PD-1 inhibition may influence memory responses in patients.

5.
Immunity ; 52(5): 825-841.e8, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32396847

RESUMO

CD8+ T cell exhaustion is a major barrier to current anti-cancer immunotherapies. Despite this, the developmental biology of exhausted CD8+ T cells (Tex) remains poorly defined, restraining improvement of strategies aimed at "re-invigorating" Tex cells. Here, we defined a four-cell-stage developmental framework for Tex cells. Two TCF1+ progenitor subsets were identified, one tissue restricted and quiescent and one more blood accessible, that gradually lost TCF1 as it divided and converted to a third intermediate Tex subset. This intermediate subset re-engaged some effector biology and increased upon PD-L1 blockade but ultimately converted into a fourth, terminally exhausted subset. By using transcriptional and epigenetic analyses, we identified the control mechanisms underlying subset transitions and defined a key interplay between TCF1, T-bet, and Tox in the process. These data reveal a four-stage developmental hierarchy for Tex cells and define the molecular, transcriptional, and epigenetic mechanisms that could provide opportunities to improve cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Epigênese Genética/imunologia , Neoplasias/imunologia , Subpopulações de Linfócitos T/imunologia , Transcrição Genética/imunologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Epigênese Genética/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/imunologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/imunologia , Humanos , Imunoterapia/métodos , Camundongos Endogâmicos C57BL , Neoplasias/genética , Neoplasias/terapia , Proteínas com Domínio T/genética , Proteínas com Domínio T/imunologia , Subpopulações de Linfócitos T/metabolismo , Transcrição Genética/genética
6.
Immunity ; 51(5): 840-855.e5, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31606264

RESUMO

TCF-1 is a key transcription factor in progenitor exhausted CD8 T cells (Tex). Moreover, this Tex cell subset mediates responses to PD-1 checkpoint pathway blockade. However, the role of the transcription factor TCF-1 in early fate decisions and initial generation of Tex cells is unclear. Single-cell RNA sequencing (scRNA-seq) and lineage tracing identified a TCF-1+Ly108+PD-1+ CD8 T cell population that seeds development of mature Tex cells early during chronic infection. TCF-1 mediated the bifurcation between divergent fates, repressing development of terminal KLRG1Hi effectors while fostering KLRG1Lo Tex precursor cells, and PD-1 stabilized this TCF-1+ Tex precursor cell pool. TCF-1 mediated a T-bet-to-Eomes transcription factor transition in Tex precursors by promoting Eomes expression and drove c-Myb expression that controlled Bcl-2 and survival. These data define a role for TCF-1 in early-fate-bifurcation-driving Tex precursor cells and also identify PD-1 as a protector of this early TCF-1 subset.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Redes Reguladoras de Genes , Fator 1 de Transcrição de Linfócitos T/metabolismo , Transcrição Genética , Animais , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Doença Crônica , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Camundongos , Receptor de Morte Celular Programada 1/metabolismo , Fator 1 de Transcrição de Linfócitos T/genética , Viroses/genética , Viroses/imunologia , Viroses/virologia
8.
Nature ; 571(7764): 211-218, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31207603

RESUMO

Exhausted CD8+ T (Tex) cells in chronic infections and cancer have limited effector function, high co-expression of inhibitory receptors and extensive transcriptional changes compared with effector (Teff) or memory (Tmem) CD8+ T cells. Tex cells are important clinical targets of checkpoint blockade and other immunotherapies. Epigenetically, Tex cells are a distinct immune subset, with a unique chromatin landscape compared with Teff and Tmem cells. However, the mechanisms that govern the transcriptional and epigenetic development of Tex cells remain unknown. Here we identify the HMG-box transcription factor TOX as a central regulator of Tex cells in mice. TOX is largely dispensable for the formation of Teff and Tmem cells, but it is critical for exhaustion: in the absence of TOX, Tex cells do not form. TOX is induced by calcineurin and NFAT2, and operates in a feed-forward loop in which it becomes calcineurin-independent and sustained in Tex cells. Robust expression of TOX therefore results in commitment to Tex cells by translating persistent stimulation into a distinct Tex cell transcriptional and epigenetic developmental program.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Epistasia Genética , Proteínas de Homeodomínio/metabolismo , Transcrição Genética , Animais , Calcineurina/metabolismo , Sinalização do Cálcio , Retroalimentação Fisiológica , Feminino , Regulação da Expressão Gênica/imunologia , Genótipo , Memória Imunológica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/metabolismo , Evasão Tumoral
9.
Cancer Res ; 78(4): 1003-1016, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29229601

RESUMO

Extracellular adenosine is a key immunosuppressive metabolite that restricts activation of cytotoxic lymphocytes and impairs antitumor immune responses. Here, we show that engagement of A2A adenosine receptor (A2AR) acts as a checkpoint that limits the maturation of natural killer (NK) cells. Both global and NK-cell-specific conditional deletion of A2AR enhanced proportions of terminally mature NK cells at homeostasis, following reconstitution, and in the tumor microenvironment. Notably, A2AR-deficient, terminally mature NK cells retained proliferative capacity and exhibited heightened reconstitution in competitive transfer assays. Moreover, targeting A2AR specifically on NK cells also improved tumor control and delayed tumor initiation. Taken together, our results establish A2AR-mediated adenosine signaling as an intrinsic negative regulator of NK-cell maturation and antitumor immune responses. On the basis of these findings, we propose that administering A2AR antagonists concurrently with NK cell-based therapies may heighten therapeutic benefits by augmenting NK cell-mediated antitumor immunity.Significance: Ablating adenosine signaling is found to promote natural killer cell maturation and antitumor immunity and reduce tumor growth. Cancer Res; 78(4); 1003-16. ©2017 AACR.


Assuntos
Células Matadoras Naturais/patologia , Melanoma Experimental/metabolismo , Receptor A2A de Adenosina/metabolismo , Animais , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Células Matadoras Naturais/imunologia , Masculino , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptor A2A de Adenosina/deficiência , Receptor A2A de Adenosina/imunologia , Transdução de Sinais/imunologia , Microambiente Tumoral/imunologia
10.
Nat Immunol ; 18(9): 1004-1015, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28759001

RESUMO

Avoiding destruction by immune cells is a hallmark of cancer, yet how tumors ultimately evade control by natural killer (NK) cells remains incompletely defined. Using global transcriptomic and flow-cytometry analyses and genetically engineered mouse models, we identified the cytokine-TGF-ß-signaling-dependent conversion of NK cells (CD49a-CD49b+Eomes+) into intermediate type 1 innate lymphoid cell (intILC1) (CD49a+CD49b+Eomes+) populations and ILC1 (CD49a+CD49b-Eomesint) populations in the tumor microenvironment. Strikingly, intILC1s and ILC1s were unable to control local tumor growth and metastasis, whereas NK cells favored tumor immunosurveillance. Experiments with an antibody that neutralizes the cytokine TNF suggested that escape from the innate immune system was partially mediated by TNF-producing ILC1s. Our findings provide new insight into the plasticity of group 1 ILCs in the tumor microenvironment and suggest that the TGF-ß-driven conversion of NK cells into ILC1s is a previously unknown mechanism by which tumors escape surveillance by the innate immune system.


Assuntos
Reprogramação Celular/imunologia , Fibrossarcoma/imunologia , Neoplasias Gastrointestinais/imunologia , Tumores do Estroma Gastrointestinal/imunologia , Imunidade Inata/imunologia , Células Matadoras Naturais/imunologia , Neoplasias Experimentais/imunologia , Evasão Tumoral/imunologia , Animais , Estudos de Casos e Controles , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Células Matadoras Naturais/citologia , Linfócitos/citologia , Linfócitos/imunologia , Camundongos , Análise de Sequência de RNA , Transdução de Sinais , Fator de Crescimento Transformador beta/imunologia
11.
Cancer Res ; 77(16): 4434-4447, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28655790

RESUMO

T-cell infiltration of solid tumors is associated with improved prognosis and favorable responses to immunotherapy. Mechanisms that enable tumor infiltration of CD8+ T cells have not been defined, nor have drugs that assist this process been discovered. Here we address these issues with a focus on VE-cadherin, a major endothelial cell-specific junctional protein that controls vascular integrity. A decrease in VE-cadherin expression is associated with tumor pathology. We developed an oligonucleotide-based inhibitor (CD5-2), which disrupted the interaction of VE-cadherin with its regulator miR-27a, resulting in increased VE-cadherin expression. Administration of CD5-2 in tumor-bearing mice enhanced expression of VE-cadherin in tumor endothelium, activating TIE-2 and tight junction pathways and normalizing vessel structure and function. CD5-2 administration also enhanced tumor-specific T-cell infiltration and spatially redistributed CD8+ T cells within the tumor parenchyma. Finally, CD5-2 treatment enhanced the efficacy of anti-PD-1 blocking antibody. Our work establishes a role for VE-cadherin in T-cell infiltration in tumors and offers a preclinical proof of concept for CD5-2 as a therapeutic modifier of cancer immunotherapy via effects on the tumor vasculature. Cancer Res; 77(16); 4434-47. ©2017 AACR.


Assuntos
Caderinas/imunologia , Neoplasias do Colo/terapia , Endotélio Vascular/imunologia , Imunoterapia/métodos , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/terapia , Linfócitos T/imunologia , Animais , Neoplasias do Colo/irrigação sanguínea , Neoplasias do Colo/imunologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Melanoma Experimental/imunologia , Camundongos , Terapia de Alvo Molecular
12.
Cancer Res ; 77(17): 4684-4696, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28652244

RESUMO

Increasing evidence exists for the role of immunosuppressive adenosine in promoting tumor growth and spread in a number of cancer types, resulting in poor clinical outcomes. In this study, we assessed whether the CD73-adenosinergic pathway is active in melanoma patients and whether adenosine restricts the efficacy of clinically approved targeted therapies for commonly mutated BRAFV600E melanoma. In AJCC stage III melanoma patients, CD73 expression (the enzyme that generates adenosine) correlated significantly with patients presenting nodal metastatic melanoma, suggesting that targeting this pathway may be effective in advanced stage disease. In addition, dabrafenib and trametinib treatment of CD73+ BRAFV600E-mutant melanomas caused profound CD73 downregulation in tumor cells. Inhibition of BRAF and MEK in combination with the A2A adenosine receptor provided significant protection against tumor initiation and metastasis formation in mice. Our results suggest that targeting adenosine may enhance therapeutic responses for melanoma patients receiving targeted or immune-based therapies. Cancer Res; 77(17); 4684-96. ©2017 AACR.


Assuntos
Adenosina/metabolismo , Neoplasias Pulmonares/prevenção & controle , Melanoma/prevenção & controle , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Receptor A2A de Adenosina/química , Neoplasias Cutâneas/prevenção & controle , 5'-Nucleotidase/metabolismo , Animais , Quimioterapia Combinada , Proteínas Ligadas por GPI/metabolismo , Humanos , Imidazóis/farmacologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , MAP Quinase Quinase 1/antagonistas & inibidores , Melanoma/genética , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Terapia de Alvo Molecular , Mutação/genética , Oximas/farmacologia , Piridonas/farmacologia , Pirimidinonas/farmacologia , Receptor A2A de Adenosina/fisiologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/secundário
13.
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
14.
Proc Natl Acad Sci U S A ; 114(27): 7077-7082, 2017 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-28630300

RESUMO

G9a is an epigenetic regulator that methylates H3K9, generally causing repression of gene expression, and participates in diverse cellular functions. G9a is genetically deregulated in a variety of tumor types and can silence tumor suppressor genes and, therefore, is important for carcinogenesis. Although hypoxia is recognized to be an adverse factor in tumor growth and metastasis, the role of G9a in regulating gene expression in hypoxia has not been described extensively. Here, we show that G9a protein stability is increased in hypoxia via reduced proline hydroxylation and, hence, inefficient degradation by the proteasome. This inefficiency leads to an increase in H3K9me2 at its target promoters. Blocking the methyltransferase activity of G9a inhibited cellular proliferation and migration in vitro and tumor growth in vivo. Furthermore, an increased level of G9a is a crucial factor in mediating the hypoxic response by down-regulating the expression of specific genes, including ARNTL, CEACAM7, GATA2, HHEX, KLRG1, and OGN This down-regulation can be rescued by a small molecule inhibitor of G9a. Based on the hypothesis that the changes in gene expression would influence patient outcomes, we have developed a prognostic G9a-suppressed gene signature that can stratify breast cancer patients. Together, our findings provide an insight into the role G9a plays as an epigenetic mediator of hypoxic response, which can be used as a diagnostic marker, and proposes G9a as a therapeutic target for solid cancers.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Hipóxia/genética , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células , Intervalo Livre de Doença , Epigênese Genética , Feminino , Perfilação da Expressão Gênica , Humanos , Células MCF-7 , Neoplasias Mamárias Experimentais/genética , Camundongos , Camundongos Endogâmicos C57BL , Prognóstico , Prolina/química , Processamento de Proteína Pós-Traducional , RNA Interferente Pequeno/metabolismo , Recidiva , Microambiente Tumoral
15.
Cancer Discov ; 6(12): 1382-1399, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27663893

RESUMO

Immunotherapy has recently entered a renaissance phase with the approval of multiple agents for the treatment of cancer. Immunotherapy stands ready to join traditional modalities, including surgery, chemotherapy, radiation, and hormone therapy, as a pillar of cancer treatment. Although immunotherapy has begun to have success in advanced cancer treatment, its scheduling and efficacy with surgery to treat earlier stages of cancer and prevent distant metastases have not been systematically examined. Here, we have used two models of spontaneously metastatic breast cancers in mice to illustrate the significantly greater therapeutic power of neoadjuvant, compared with adjuvant, immunotherapies in the context of primary tumor resection. Elevated and sustained peripheral tumor-specific immune responses underpinned the outcome, and blood sampling of tumor-specific CD8+ T cells immediately prior to and post surgery may provide a predictor of outcome. These data now provide a strong rationale to extensively test and compare neoadjuvant immunotherapy in humans. SIGNIFICANCE: We demonstrate the significantly greater therapeutic efficacy of neoadjuvant, compared with adjuvant, immunotherapies to eradicate distant metastases following primary tumor resection. Elevated and sustained peripheral tumor-specific immune responses underpinned the outcome, and blood sampling of tumor-specific CD8+ T cells immediately prior to and post surgery may provide a predictor of outcome. Cancer Discov; 6(12); 1382-99. ©2016 AACR.See related commentary by Melero et al., p. 1312This article is highlighted in the In This Issue feature, p. 1293.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante/métodos , Terapia Neoadjuvante/métodos , Animais , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Feminino , Humanos , Imunoterapia/métodos , Camundongos , Metástase Neoplásica , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Cancer Cell ; 30(3): 391-403, 2016 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-27622332

RESUMO

Preclinical studies targeting the adenosinergic pathway have gained much attention for their clinical potential in overcoming tumor-induced immunosuppression. Here, we have identified that co-blockade of the ectonucleotidase that generates adenosine CD73 and the A2A adenosine receptor (A2AR) that mediates adenosine signaling in leuokocytes, by using compound gene-targeted mice or therapeutics that target these molecules, limits tumor initiation, growth, and metastasis. This tumor control requires effector lymphocytes and interferon-γ, while antibodies targeting CD73 promote an optimal therapeutic response in vivo when engaging activating Fc receptors. In a two-way mixed leukocyte reaction using a fully human anti-CD73, we demonstrated that Fc receptor binding augmented the production of proinflammatory cytokines.


Assuntos
5'-Nucleotidase/antagonistas & inibidores , Antagonistas do Receptor A2 de Adenosina/farmacologia , Tolerância Imunológica/imunologia , Neoplasias/imunologia , Neoplasias/terapia , 5'-Nucleotidase/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Feminino , Humanos , Masculino , Neoplasias Mamárias Experimentais/imunologia , Neoplasias Mamárias Experimentais/terapia , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias/patologia , Receptor A2A de Adenosina/imunologia , Transdução de Sinais
17.
Cancer Res ; 76(21): 6266-6277, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27634762

RESUMO

The durability and efficacy of anti-human PD1 monoclonal antibodies (PD1 mAb) vary across different malignancies. Although an absence of tumor-infiltrating cytotoxic T lymphocytes has been identified as a cause for resistance to PD1 mAb, the presence of intratumor exhausted PD1hi T cells also contributes to insensitivity to this immune checkpoint therapy. In this study, we used mouse tumor models of PD1 mAb resistance that harbored PD1hi T cells and flow cytometry analysis of tumor-infiltrating leukocytes immediately post-therapy as a screening platform to identify agents that could resensitize T cells to PD1 blockade. We showed that an agonistic anti-CD40 mAb converted PD1hi T cells into PD1lo T cells, reversing phenotypic T-cell exhaustion and allowing the anti-PD1 refractory tumors to respond to anti-PD1 therapy. PD1 downmodulation by anti-CD40 mAb relied upon IL12 but not IL23, CD80/CD86/CD28, or CD70/CD27. Consistent with a role for regulatory T cells (Treg) in promoting T-cell exhaustion, we also showed that intratumor Treg presented with a less activated and attenuated suppressive phenotype, marked by reductions in CTLA4 and PD1. Similar to anti-CD40 mAb, anti-CTLA4 mAb also lowered intratumor T-cell PD1 expression. Our study provides a proof-of-principle framework to systematically identify immune conditioning agents able to convert PD1hi T cells to PD1lo T cells, with clinical implications in the management of anti-PD1 refractory patients. Cancer Res; 76(21); 6266-77. ©2016 AACR.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos CD40/antagonistas & inibidores , Interleucina-12/fisiologia , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T/fisiologia , Animais , Interleucina-23/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Linfócitos T Reguladores/fisiologia
18.
Oncoimmunology ; 5(3): e1089381, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27141346

RESUMO

The presence of colony stimulating factor-1 (CSF1)/CSF1 receptor (CSF1R)-driven tumor-infiltrating macrophages and myeloid-derived suppressor cells (MDSCs) is shown to promote targeted therapy resistance. In this study, we demonstrate the superior effect of a combination of CSF1R inhibitor, PLX3397 and BRAF inhibitor, PLX4720, in suppressing primary and metastatic mouse BRAFV600E melanoma. Using flow cytometry to assess SM1WT1 melanoma-infiltrating leukocytes immediately post therapy, we found that PLX3397 reduced the recruitment of CD11b+ Gr1lo and CD11b+ Gr1int M2-like macrophages, but this was accompanied by an accumulation of CD11b+ Gr1hi cells. PDL1 expression on remaining myeloid cells potentially dampened the antitumor efficacy of PLX3397 and PLX4720 in combination, since PD1/PDL1 axis blockade improved outcome. We also reveal a role for PLX3397 in reducing tumor-infiltrating lymphocytes, and interestingly, this feature was rescued by the co-administration of PLX4720. Our findings, from three different mouse models of BRAF-mutated melanoma, support clinical approaches that co-target BRAF oncogene and CSF1R.

19.
Adv Immunol ; 130: 1-24, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26922998

RESUMO

Immunotherapy is now evolving into a major therapeutic option for cancer patients. Such clinical advances also promote massive interest in the search for novel immunotherapy targets, and to understand the mechanism of action of current drugs. It is projected that a series of novel immunotherapy agents will be developed and assessed for their therapeutic activity. In light of this, in vivo experimental mouse models that recapitulate human malignancies serve as valuable tools to validate the efficacy and safety profile of immunotherapy agents, before their transition into clinical trials. In this review, we will discuss the major classes of experimental mouse models of cancer commonly used for immunotherapy assessment and provide examples to guide the selection of appropriate models. We present some new data concerning the utility of a carcinogen-induced tumor model for comparing immunotherapies and combining immunotherapy with chemotherapy. We will also highlight some recent advances in experimental modeling of human malignancies in mice that are leading towards personalized therapy in patients.


Assuntos
Imunoterapia , Neoplasias Experimentais/terapia , Microambiente Tumoral/imunologia , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Transplante de Neoplasias , Neoplasias Experimentais/induzido quimicamente
20.
Nat Rev Clin Oncol ; 13(3): 143-58, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26598942

RESUMO

Evidence suggests that cancer immunotherapy will be a major part of the combination treatment plan for many patients with many cancer types in the near future. There are many types of immune processes involving different antitumour and tumour-promoting leucocytes, and tumour cells use many strategies to evade the immune response. The tumour microenvironment can help determine which immune suppressive pathways become activated to restrain antitumour immunity. This includes immune checkpoint receptors on effector T-cells and myeloid cells, and release of inhibitory cytokines and metabolites. Therapeutic approaches that target these pathways, particularly immune-checkpoint receptors, can induce durable antitumour responses in patients with advanced-stage cancers, including melanoma. Nevertheless, many patients do not have a good response to monotherapy approaches and alternative strategies are required to achieve optimal therapeutic benefit. These strategies include eliminating the bulk of tumour cells to provoke tumour-antigen release and antigen-presenting cell (APC) function, using adjuvants to enhance APC function, and using agents that enhance effector-cell activity. In this Review, we discuss the stratification of the tumour microenvironment according to tumour-infiltrating lymphocytes and PD-L1 expression in the tumour, and how this stratification enables the design of optimal combination cancer therapies tailored to target different tumour microenvironments.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Microambiente Tumoral/efeitos dos fármacos , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Humanos , Terapia de Alvo Molecular , Neoplasias/imunologia , Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento , Evasão Tumoral/efeitos dos fármacos
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