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PURPOSE: Programmed death-1 (PD-1), an inhibitory receptor expressed on activated T cells, may suppress antitumor immunity. This phase I study sought to determine the safety and tolerability of anti-PD-1 blockade in patients with treatment-refractory solid tumors and to preliminarily assess antitumor activity, pharmacodynamics, and immunologic correlates. PATIENTS AND METHODS: Thirty-nine patients with advanced metastatic melanoma, colorectal cancer (CRC), castrate-resistant prostate cancer, non-small-cell lung cancer (NSCLC), or renal cell carcinoma (RCC) received a single intravenous infusion of anti-PD-1 (MDX-1106) in dose-escalating six-patient cohorts at 0.3, 1, 3, or 10 mg/kg, followed by a 15-patient expansion cohort at 10 mg/kg. Patients with evidence of clinical benefit at 3 months were eligible for repeated therapy. RESULTS: Anti-PD-1 was well tolerated: one serious adverse event, inflammatory colitis, was observed in a patient with melanoma who received five doses at 1 mg/kg. One durable complete response (CRC) and two partial responses (PRs; melanoma, RCC) were seen. Two additional patients (melanoma, NSCLC) had significant lesional tumor regressions not meeting PR criteria. The serum half-life of anti-PD-1 was 12 to 20 days. However, pharmacodynamics indicated a sustained mean occupancy of > 70% of PD-1 molecules on circulating T cells ≥ 2 months following infusion, regardless of dose. In nine patients examined, tumor cell surface B7-H1 expression appeared to correlate with the likelihood of response to treatment. CONCLUSION: Blocking the PD-1 immune checkpoint with intermittent antibody dosing is well tolerated and associated with evidence of antitumor activity. Exploration of alternative dosing regimens and combinatorial therapies with vaccines, targeted therapies, and/or other checkpoint inhibitors is warranted.
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Novel therapeutic approaches combining immune-checkpoint inhibitors are needed to improve clinical outcomes for patients with cancer. Lymphocyte-activation gene 3 (LAG-3) is an immune-checkpoint molecule that inhibits T-cell activity and antitumor immune responses, acting through an independent mechanism from that of programmed death-1 (PD-1) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4). Here, we describe the development and preclinical characterization of relatlimab, a human antibody that binds to human LAG-3 with high affinity and specificity to block the interaction of LAG-3 with the ligands MHC II and fibrinogen-like protein-1, and to reverse LAG-3-mediated inhibition of T-cell function in vitro. Consistent with previous reports, in mouse models, the combined blockade of LAG-3 and PD-1 with surrogate antibodies resulted in enhanced antitumor activity greater than the individual blockade of either receptor. In toxicity studies in cynomolgus monkeys, relatlimab was generally well tolerated when combined with nivolumab. These results are consistent with findings from the RELATIVITY-047 phase II/III trial showing that relatlimab combined with nivolumab is a well-tolerated regimen that demonstrates superior progression-free survival compared with nivolumab monotherapy in patients with unresectable or metastatic melanoma.
Assuntos
Melanoma , Nivolumabe , Animais , Anticorpos Bloqueadores/uso terapêutico , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Antígeno CTLA-4 , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Fibrinogênio/uso terapêutico , Humanos , Inibidores de Checkpoint Imunológico , Macaca fascicularis , Melanoma/patologia , Camundongos , Nivolumabe/uso terapêutico , Receptor de Morte Celular Programada 1RESUMO
T cell immunoglobulin mucin domain-containing protein 3 (Tim-3) negatively regulates innate and adaptive immunity in cancer. To identify the mechanisms of Tim-3 in cancer immunity, we evaluated the effects of Tim-3 blockade in human and mouse melanoma. Here, we show that human programmed cell death 1-positive (PD-1+) Tim-3+CD8+ tumor-infiltrating lymphocytes (TILs) upregulate phosphatidylserine (PS), a receptor for Tim-3, and acquire cell surface myeloid markers from antigen-presenting cells (APCs) through transfer of membrane fragments called trogocytosis. Tim-3 blockade acted on Tim-3+ APCs in a PS-dependent fashion to disrupt the trogocytosis of activated tumor antigen-specific CD8+ T cells and PD-1+Tim-3+ CD8+ TILs isolated from patients with melanoma. Tim-3 and PD-1 blockades cooperated to disrupt trogocytosis of CD8+ TILs in 2 melanoma mouse models, decreasing tumor burden and prolonging survival. Deleting Tim-3 in dendritic cells but not in CD8+ T cells impeded the trogocytosis of CD8+ TILs in vivo. Trogocytosed CD8+ T cells presented tumor peptide-major histocompatibility complexes and became the target of fratricide T cell killing, which was reversed by Tim-3 blockade. Our findings have uncovered a mechanism Tim-3 uses to limit antitumor immunity.
Assuntos
Receptor Celular 2 do Vírus da Hepatite A/imunologia , Melanoma , Animais , Linfócitos T CD8-Positivos , Receptor Celular 2 do Vírus da Hepatite A/genética , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Humanos , Linfócitos do Interstício Tumoral , Melanoma/patologia , Camundongos , Receptor de Morte Celular Programada 1 , TrogocitoseRESUMO
Cancer immunity, and the potential for cancer immunotherapy, have been topics of scientific discussion and experimentation for over a hundred years. Several successful cancer immunotherapies - such as IL-2 and interferon-α (IFNα) - have appeared over the past 30 years. However, it is only in the past decade that immunotherapy has made a broad impact on patient survival in multiple high-incidence cancer indications. The emergence of immunotherapy as a new pillar of cancer treatment (adding to surgery, radiation, chemotherapy and targeted therapies) is due to the success of immune checkpoint blockade (ICB) drugs, the first of which - ipilimumab - was approved in 2011. ICB drugs block receptors and ligands involved in pathways that attenuate T cell activation - such as cytotoxic T lymphocyte antigen 4 (CTLA4), programmed cell death 1 (PD1) and its ligand, PDL1 - and prevent, or reverse, acquired peripheral tolerance to tumour antigens. In this Review we mark the tenth anniversary of the approval of ipilimumab and discuss the foundational scientific history of ICB, together with the history of the discovery, development and elucidation of the mechanism of action of the first generation of drugs targeting the CTLA4 and PD1 pathways.
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Inibidores de Checkpoint Imunológico , Neoplasias , Antígeno CTLA-4 , Humanos , Imunoterapia , Ipilimumab/farmacologia , Ipilimumab/uso terapêutico , Receptor de Morte Celular Programada 1RESUMO
Costimulation via CD137 (4-1BB) enhances antitumor immunity mediated by cytotoxic T lymphocytes. Anti-CD137 agonist antibodies elicit mild liver inflammation in mice, and the maximum tolerated dose of Urelumab, an anti-human CD137 agonist monoclonal antibody, in the clinic was defined by liver inflammation-related side effects. A protease-activated prodrug form of the anti-mouse CD137 agonist antibody 1D8 (1D8 Probody therapeutic, Pb-Tx) was constructed and found to be selectively activated in the tumor microenvironment. This construct, which encompasses a protease-cleavable linker holding in place a peptide that masks the antigen binding site, exerted antitumor effects comparable to the unmodified antibody but did not result in liver inflammation. Moreover, it efficaciously synergized with both PD-1 blockade and adoptive T-cell therapy. Surprisingly, minimal active Pb-Tx reached tumor-draining lymph nodes, and regional lymphadenectomy did not abrogate antitumor efficacy. By contrast, S1P receptor-dependent recirculation of T cells was absolutely required for efficacy. The preferential cleavage of the anti-CD137 Pb-Tx by tumor proteases offers multiple therapeutic opportunities, including neoadjuvant therapy, as shown by experiments in which the Pb-Tx is given prior to surgery to avoid spontaneous metastases.
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Antineoplásicos/toxicidade , Antineoplásicos/uso terapêutico , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Imunoterapia , Inflamação/patologia , Fígado/patologia , Neoplasias Pulmonares/secundário , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Camundongos , Terapia Neoadjuvante , Peptídeo Hidrolases/metabolismoRESUMO
FOXP3+ regulatory T cells (Treg) play a critical role in mediating tolerance to self-antigens and can repress antitumor immunity through multiple mechanisms. Therefore, targeted depletion of tumor-resident Tregs is warranted to promote effective antitumor immunity while preserving peripheral homeostasis. Here, we propose the chemokine receptor CCR8 as one such optimal tumor Treg target. CCR8 was expressed by Tregs in both murine and human tumors, and unlike CCR4, a Treg depletion target in the clinic, CCR8 was selectively expressed on suppressive tumor Tregs and minimally expressed on proinflammatory effector T cells (Teff). Preclinical mouse tumor modeling showed that depletion of CCR8+ Tregs through an FcyR-engaging anti-CCR8 antibody, but not blockade, enabled dose-dependent, effective, and long-lasting antitumor immunity that synergized with PD-1 blockade. This depletion was tumor Treg-restricted, sparing CCR8+ T cells in the spleen, thymus, and skin of mice. Importantly, Fc-optimized, nonfucosylated (nf) anti-human CCR8 antibodies specifically depleted Tregs and not Teffs in ex vivo tumor cultures from primary human specimens. These findings suggest that anti-CCR8-nf antibodies may deliver optimal tumor-targeted Treg depletion in the clinic, providing long-term antitumor memory responses while limiting peripheral toxicities. SIGNIFICANCE: These findings show that selective depletion of regulatory T cells with an anti-CCR8 antibody can improve antitumor immune responses as a monotherapy or in combination with other immunotherapies. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/81/11/2983/F1.large.jpg.
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Anticorpos Monoclonais/farmacologia , Regulação Neoplásica da Expressão Gênica , Tolerância Imunológica/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Neoplasias/imunologia , Receptores CCR8/antagonistas & inibidores , Linfócitos T Reguladores/imunologia , Animais , Apoptose , Proliferação de Células , Feminino , Humanos , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/patologia , Neoplasias/terapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptores CCR8/imunologia , Pele/efeitos dos fármacos , Pele/imunologia , Pele/metabolismo , Pele/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Unlike several other tumor types, prostate cancer rarely responds to immune checkpoint blockade (ICB). To define tumor cell intrinsic factors that contribute to prostate cancer progression and resistance to ICB, we analyzed prostate cancer epithelial cells from castration-sensitive and -resistant samples using implanted tumors, cell lines, transgenic models and human tissue. We found that castration resulted in increased expression of interleukin-8 (IL-8) and its probable murine homolog Cxcl15 in prostate epithelial cells. We showed that these chemokines drove subsequent intratumoral infiltration of tumor-promoting polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs), which was largely abrogated when IL-8 signaling was blocked genetically or pharmacologically. Targeting IL-8 signaling in combination with ICB delayed the onset of castration resistance and increased the density of polyfunctional CD8 T cells in tumors. Our findings establish a novel mechanism by which castration mediates IL-8 secretion and subsequent PMN-MDSC infiltration, and highlight blockade of the IL-8/CXCR2 axis as a potential therapeutic intervention.
Assuntos
Células Supressoras Mieloides , Neoplasias da Próstata , Animais , Castração , Humanos , Interleucina-8/genética , Masculino , Camundongos , Próstata , Neoplasias da Próstata/genéticaRESUMO
Advanced ovarian cancer (OC) patients have a poor 5-year survival of only 28%, emphasizing the medical need for improved therapies. Adjuvant immunotherapy could be an attractive approach since OC is an immunogenic disease and the presence of tumor-infiltrating lymphocytes has shown to positively correlate with patient survival. Among these infiltrating lymphocytes are natural killer (NK) cells, key players involved in tumor targeting, initiated by signaling via activating and inhibitory receptors. Here, we investigated the role of the DNAM-1/TIGIT/CD96 axis in the anti-tumor response of NK cells toward OC. Ascites-derived NK cells from advanced OC patients showed lower expression of activating receptor DNAM-1 compared to healthy donor peripheral blood NK cells, while inhibitory receptor TIGIT and CD96 expression was equal or higher, respectively. This shift to a more inhibitory phenotype could also be induced in vitro by co-culturing healthy donor NK cells with OC tumor spheroids, and in vivo on intraperitoneally infused NK cells in SKOV-3 OC bearing NOD/SCID-IL2Rγnull (NSG) mice. Interestingly, TIGIT blockade enhanced degranulation and interferon gamma (IFNγ) production of healthy donor CD56dim NK cells in response to OC tumor cells, especially when DNAM-1/CD155 interactions were in place. Importantly, TIGIT blockade boosted functional responsiveness of CD56dim NK cells of OC patients with a baseline reactivity against SKOV-3 cells. Overall, our data show for the first time that checkpoint molecules TIGIT/DNAM-1/CD96 play an important role in NK cell responsiveness against OC, and provides rationale for incorporating TIGIT interference in NK cell-based immunotherapy in OC patients.
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Células Matadoras Naturais , Neoplasias Ovarianas , Animais , Antígenos CD , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias Ovarianas/tratamento farmacológico , Receptores Imunológicos/genéticaRESUMO
A Correction to this paper has been published: https://doi.org/10.1038/s41467-020-20129-9.
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PURPOSE: Natural killer (NK) cells play a critical role in tumor immunosurveillance. Multiple activating and inhibitory receptors (IR) regulate NK-cell-mediated tumor control. The IR T-cell immunoglobulin and ITIM domain (TIGIT) and its counter-receptor CD226 exert opposite effects on NK-cell-mediated tumor reactivity. EXPERIMENTAL DESIGN: We evaluated the frequency, phenotype, and functions of NK cells freshly isolated from healthy donors and patients with melanoma with multiparameter flow cytometry. We assessed TIGIT and CD226 cell surface expression and internalization upon binding to CD155. We evaluated the role of IL15 and TIGIT blockade in increasing NK-cell-mediated cytotoxicity in vitro and in two mouse models. RESULTS: NK cells are present at low frequencies in metastatic melanoma, are dysfunctional, and downregulate both TIGIT and CD226 expression. As compared with TIGIT- NK cells, TIGIT+ NK cells exhibit higher cytotoxic capacity and maturation, but paradoxically lower cytotoxicity against CD155+ MHC class I-deficient melanoma cells. Membrane bound CD155 triggers CD226 internalization and degradation, resulting in decreased NK-cell-mediated tumor reactivity. IL15 increases TIGIT and CD226 gene expression by tumor-infiltrating NK cells (TiNKs) and, together with TIGIT blockade, increases NK-cell-mediated melanoma cytotoxicity in vitro and decreases tumor metastasis in two mouse melanoma models. Specific deletion of TIGIT on transferred NK cells enhances the antimetastatic activity of IL15, while CD226 blockade decreases the effects of IL15 and TIGIT blockade. CONCLUSIONS: Our findings support the development of novel combinatorial immunotherapy with IL15 and TIGIT blockade to promote NK-cell-mediated destruction of MHC class I-deficient melanoma, which are refractory to CD8+ T-cell-mediated immunity.See related commentary by Pietra et al., p. 5274.
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Interleucina-15/farmacologia , Células Matadoras Naturais/imunologia , Melanoma/imunologia , Receptores Imunológicos/genética , Animais , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Interleucina-15/genética , Células Matadoras Naturais/efeitos dos fármacos , Melanoma/sangue , Melanoma/genética , Melanoma/patologia , Camundongos , Receptores Imunológicos/antagonistas & inibidores , Receptores Virais/genéticaRESUMO
Despite advancements in targeting the immune checkpoints program cell death protein 1 (PD-1), programmed death ligand 1 (PD-L1), and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) for cancer immunotherapy, a large number of patients and cancer types remain unresponsive. Current immunotherapies focus on modulating an antitumor immune response by directly or indirectly expanding antitumor CD8 T cells. A complementary strategy might involve inhibition of Tregs that otherwise suppress antitumor immune responses. Here, we sought to identify functional immune molecules preferentially expressed on tumor-infiltrating Tregs. Using genome-wide RNA-Seq analysis of purified Tregs sorted from multiple human cancer types, we identified a conserved Treg immune checkpoint signature. Using immunocompetent murine tumor models, we found that antibody-mediated depletion of 4-1BB-expressing cells (4-1BB is also known as TNFRSF9 or CD137) decreased tumor growth without negatively affecting CD8 T cell function. Furthermore, we found that the immune checkpoint 4-1BB had a high selectivity for human tumor Tregs and was associated with worse survival outcomes in patients with multiple tumor types. Thus, antibody-mediated depletion of 4-1BB-expressing Tregs represents a strategy with potential activity across cancer types.
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Ligante 4-1BB/imunologia , Linfócitos do Interstício Tumoral/imunologia , Proteínas de Neoplasias/imunologia , Neoplasias Experimentais/imunologia , Linfócitos T Reguladores/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Estudo de Associação Genômica Ampla , Humanos , Depleção Linfocítica , Linfócitos do Interstício Tumoral/patologia , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , RNA-Seq , Linfócitos T Reguladores/patologiaRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Cancers induced by human papillomaviruses (HPV) should be responsive to immunotherapy by virtue of expressing the immunogenic oncoproteins E6/E7. However, advanced forms of cervical cancer, driven by HPV, are poorly responsive to immune response-enhancing treatments involving therapeutic vaccination against these viral neoantigens. Leveraging a transgenic mouse model of HPV-derived cancers, K14HPV16/H2b, we demonstrated that a potent nanoparticle-based E7 vaccine, but not a conventional "liquid" vaccine, induced E7 tumor antigen-specific CD8+ T cells in cervical tumor-bearing mice. Vaccination alone or in combination with anti-PD-1/anti-CTLA4 did not elicit tumor regression nor increase CD8+ T cells in the tumor microenvironment (TME), suggesting the presence of immune-suppressive barriers. Patients with cervical cancer have poor dendritic cell functions, have weak cytotoxic lymphocyte responses, and demonstrate an accumulation of myeloid cells in the periphery. Here, we illustrated that myeloid cells in K14HPV16/H2b mice possess potent immunosuppressive activity toward antigen-presenting cells and CD8+ T cells, dampening antitumor immunity. These immune-inhibitory effects inhibited synergistic effects of combining our oncoprotein vaccine with immune checkpoint-blocking antibodies. Our data highlighted a link between HPV-induced cancers, systemic amplification of myeloid cells, and the detrimental effects of myeloid cells on CD8+ T-cell activation and recruitment into the TME. These results established immunosuppressive myeloid cells in lymphoid organs as an HPV+ cancer-induced means of circumventing tumor immunity that will require targeted abrogation to enable the induction of efficacious antitumor immune responses.
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Antineoplásicos Imunológicos/farmacologia , Linfócitos T CD8-Positivos/imunologia , Células Mieloides/imunologia , Papillomaviridae/imunologia , Infecções por Papillomavirus/imunologia , Vacinas contra Papillomavirus/imunologia , Neoplasias do Colo do Útero/imunologia , Animais , Antígeno CTLA-4/antagonistas & inibidores , Modelos Animais de Doenças , Sinergismo Farmacológico , Feminino , Humanos , Terapia de Imunossupressão , Imunoterapia/métodos , Camundongos , Células Mieloides/efeitos dos fármacos , Nanopartículas/administração & dosagem , Proteínas E7 de Papillomavirus/imunologia , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/tratamento farmacológico , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/administração & dosagem , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Microambiente Tumoral , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologiaRESUMO
Co-inhibitory immune receptors can contribute to T cell dysfunction in patients with cancer1,2. Blocking antibodies against cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1) partially reverse this effect and are becoming standard of care in an increasing number of malignancies3. However, many of the other axes by which tumours become inhospitable to T cells are not fully understood. Here we report that V-domain immunoglobulin suppressor of T cell activation (VISTA) engages and suppresses T cells selectively at acidic pH such as that found in tumour microenvironments. Multiple histidine residues along the rim of the VISTA extracellular domain mediate binding to the adhesion and co-inhibitory receptor P-selectin glycoprotein ligand-1 (PSGL-1). Antibodies engineered to selectively bind and block this interaction in acidic environments were sufficient to reverse VISTA-mediated immune suppression in vivo. These findings identify a mechanism by which VISTA may engender resistance to anti-tumour immune responses, as well as an unexpectedly determinative role for pH in immune co-receptor engagement.
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Antígenos B7/química , Antígenos B7/metabolismo , Glicoproteínas de Membrana/metabolismo , Linfócitos T/metabolismo , Animais , Anticorpos Bloqueadores/imunologia , Anticorpos Bloqueadores/farmacologia , Antígenos B7/antagonistas & inibidores , Antígenos B7/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Cristalografia por Raios X , Epitopos de Linfócito B/química , Epitopos de Linfócito B/imunologia , Feminino , Histidina/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Ligantes , Masculino , Glicoproteínas de Membrana/imunologia , Camundongos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos , Linfócitos T/citologia , Linfócitos T/imunologia , Microambiente Tumoral/imunologiaRESUMO
PURPOSE: The success of checkpoint blockade has led to a significant increase in the development of a broad range of immunomodulatory molecules for the treatment of cancer, including agonists against T-cell costimulatory receptors, such as OX40. Unlike checkpoint blockade, where complete and sustained receptor saturation may be required for maximal activity, the optimal dosing regimen and receptor occupancy for agonist agents is less well understood and requires further study. EXPERIMENTAL DESIGN: We integrated both preclinical and clinical biomarker data sets centered on dose, exposure, receptor occupancy, receptor engagement, and downstream pharmacodynamic changes to model the optimal dose and schedule for the OX40 agonist antibody BMS-986178 alone and in combination with checkpoint blockade. RESULTS: Administration of the ligand-blocking anti-mouse surrogate antibody OX40.23 or BMS-986178 as monotherapy or in combination with checkpoint blockade led to increased peripheral CD4+ and CD8+ T-cell activation in tumor-bearing mice and patients with solid tumors, respectively. OX40 receptor occupancy between 20% and 50% both in vitro and in vivo was associated with maximal enhancement of T-cell effector function by anti-OX40 treatment, whereas a receptor occupancy > 40% led to a profound loss in OX40 receptor expression, with clear implications for availability for repeat dosing. CONCLUSIONS: Our results highlight the value of an integrated translational approach applied during early clinical development to aggregate preclinical and clinical data in an effort to define the optimal dose and schedule for T-cell agonists in the clinic.
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Antineoplásicos Imunológicos/uso terapêutico , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Receptores OX40/agonistas , Animais , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno CTLA-4/antagonistas & inibidores , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Imunofenotipagem , Camundongos , Camundongos Transgênicos , Terapia de Alvo Molecular/efeitos adversos , Terapia de Alvo Molecular/métodos , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias/metabolismo , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Brain glioma treatment with checkpoint inhibitor antibodies to cytotoxic T-lymphocyte-associated antigen 4 (a-CTLA-4) and programmed cell death-1 (a-PD-1) was largely unsuccessful due to their inability to cross blood-brain barrier (BBB). Here we describe targeted nanoscale immunoconjugates (NICs) on natural biopolymer scaffold, poly(ß-L-malic acid), with covalently attached a-CTLA-4 or a-PD-1 for systemic delivery across the BBB and activation of local brain anti-tumor immune response. NIC treatment of mice bearing intracranial GL261 glioblastoma (GBM) results in an increase of CD8+ T cells, NK cells and macrophages with a decrease of regulatory T cells (Tregs) in the brain tumor area. Survival of GBM-bearing mice treated with NIC combination is significantly longer compared to animals treated with single checkpoint inhibitor-bearing NICs or free a-CTLA-4 and a-PD-1. Our study demonstrates trans-BBB delivery of tumor-targeted polymer-conjugated checkpoint inhibitors as an effective GBM treatment via activation of both systemic and local privileged brain tumor immune response.
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Antineoplásicos Imunológicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Imunoconjugados/administração & dosagem , Nanoconjugados/química , Animais , Antineoplásicos Imunológicos/farmacocinética , Biopolímeros/química , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Linhagem Celular Tumoral/transplante , Modelos Animais de Doenças , Feminino , Glioma/imunologia , Glioma/patologia , Humanos , Imunoconjugados/química , Imunoconjugados/farmacocinética , Malatos/química , Camundongos , Permeabilidade , Physarum polycephalum/química , Polímeros/química , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Resultado do TratamentoRESUMO
While a fraction of cancer patients treated with anti-PD-1 show durable therapeutic responses, most remain unresponsive, highlighting the need to better understand and improve these therapies. Using an in vivo screening approach with a customized shRNA pooled library, we identified DDR2 as a leading target for the enhancement of response to anti-PD-1 immunotherapy. Using isogenic in vivo murine models across five different tumor histologies-bladder, breast, colon, sarcoma, and melanoma-we show that DDR2 depletion increases sensitivity to anti-PD-1 treatment compared to monotherapy. Combination treatment of tumor-bearing mice with anti-PD-1 and dasatinib, a tyrosine kinase inhibitor of DDR2, led to tumor load reduction. RNA-seq and CyTOF analysis revealed higher CD8+ T cell populations in tumors with DDR2 depletion and those treated with dasatinib when either was combined with anti-PD-1 treatment. Our work provides strong scientific rationale for targeting DDR2 in combination with PD-1 inhibitors.
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Linfócitos T CD8-Positivos/imunologia , Dasatinibe/farmacologia , Receptor com Domínio Discoidina 2/antagonistas & inibidores , Sistemas de Liberação de Medicamentos , Imunidade Celular , Imunoterapia , Neoplasias Experimentais/terapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Linfócitos T CD8-Positivos/patologia , Linhagem Celular Tumoral , Receptor com Domínio Discoidina 2/imunologia , Feminino , Camundongos , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Receptor de Morte Celular Programada 1/imunologiaRESUMO
CD4+ Tregs impede T cell responses to tumors. They express multiple inhibitory receptors that support their suppressive functions, including T cell Ig and ITIM domain (TIGIT). In melanoma patients, we show that Tregs exhibit increased TIGIT expression and decreased expression of its competing costimulatory receptor CD226 as compared with CD4+ effector T cells, resulting in an increased TIGIT/CD226 ratio. Tregs failed to upregulate CD226 upon T cell activation. TIGIT+ Tregs are highly suppressive, stable, and enriched in tumors. TIGIT and CD226 oppose each other to augment or disrupt, respectively, Treg suppression and stability. A high TIGIT/CD226 ratio in Tregs correlates with increased Treg frequencies in tumors and poor clinical outcome upon immune checkpoint blockade. Altogether, our findings show that a high TIGIT/CD226 ratio in Tregs regulates their suppressive function and stability in melanoma. They provide the rationale for novel immunotherapies to activate CD226 in Tregs together with TIGIT blockade to counteract Treg suppression in cancer patients.
Assuntos
Antígenos de Diferenciação de Linfócitos T/metabolismo , Melanoma/metabolismo , Receptores Imunológicos/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos , Citocinas , Humanos , Imunofenotipagem , Imunoterapia , Ativação Linfocitária , Melanoma/terapia , Linfócitos T Reguladores/imunologia , Proteínas Supressoras de Tumor/metabolismoRESUMO
Purpose: In the proper context, radiotherapy can promote antitumor immunity. It is unknown if elective nodal irradiation (ENI), a strategy that irradiates tumor-associated draining lymph nodes (DLN), affects adaptive immune responses and combinatorial efficacy of radiotherapy with immune checkpoint blockade (ICB).Experimental Design: We developed a preclinical model to compare stereotactic radiotherapy (Tumor RT) with or without ENI to examine immunologic differences between radiotherapy techniques that spare or irradiate the DLN.Results: Tumor RT was associated with upregulation of an intratumoral T-cell chemoattractant chemokine signature (CXCR3, CCR5-related) that resulted in robust infiltration of antigen-specific CD8+ effector T cells as well as FoxP3+ regulatory T cells (Tregs). The addition of ENI attenuated chemokine expression, restrained immune infiltration, and adversely affected survival when combined with ICB, especially with anti-CLTA4 therapy. The combination of stereotactic radiotherapy and ICB led to long-term survival in a subset of mice and was associated with favorable CD8 effector-to-Treg ratios and increased intratumoral density of antigen-specific CD8+ T cells. Although radiotherapy technique (Tumor RT vs. ENI) affected initial tumor control and survival, the ability to reject tumor upon rechallenge was partially dependent upon the mechanism of action of ICB; as radiotherapy/anti-CTLA4 was superior to radiotherapy/anti-PD-1.Conclusions: Our results highlight that irradiation of the DLN restrains adaptive immune responses through altered chemokine expression and CD8+ T-cell trafficking. These data have implications for combining radiotherapy and ICB, long-term survival, and induction of immunologic memory. Clinically, the immunomodulatory effect of the radiotherapy strategy should be considered when combining stereotactic radiotherapy with immunotherapy. Clin Cancer Res; 24(20); 5058-71. ©2018 AACR.