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1.
Life (Basel) ; 14(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38541651

RESUMO

Immuno-oncology has traditionally focused on conventional MHC-restricted αß T cells. Yet, unconventional γδ T cells, which kill tumor cells in an MHC-unrestricted manner, display characteristics of effector activity and stemness without exhaustion and are nearly universally observed in human gynecologic malignancies, correlating with improved outcomes. These cells do not have a clear counterpart in mice but are also found in the healthy female reproductive tract. Interventions that modulate their in vivo activity, or cellular therapies utilizing γδ T cells as an allogeneic, "off-the-shelf" platform (e.g., for chimeric antigen receptor expression) hold significant potential against challenging tumors like ovarian cancer, which has been stubbornly resistant to the immune checkpoint inhibitors that change the landscape of other human tumors. Here, we discuss recent discoveries on the specific populations of γδ T cells that infiltrate human gynecologic cancers, their anti-tumor activity, and the prospect of redirecting their effector function against tumor cells to develop a new generation of immunotherapies that extends beyond the traditional αß T cell-centric view of the field.

2.
Immunity ; 56(11): 2570-2583.e6, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37909039

RESUMO

Dimeric IgA (dIgA) can move through cells via the IgA/IgM polymeric immunoglobulin receptor (PIGR), which is expressed mainly on mucosal epithelia. Here, we studied the ability of dIgA to target commonly mutated cytoplasmic oncodrivers. Mutation-specific dIgA, but not IgG, neutralized KRASG12D within ovarian carcinoma cells and expelled this oncodriver from tumor cells. dIgA binding changed endosomal trafficking of KRASG12D from accumulation in recycling endosomes to aggregation in the early/late endosomes through which dIgA transcytoses. dIgA targeting of KRASG12D abrogated tumor cell proliferation in cell culture assays. In vivo, KRASG12D-specific dIgA1 limited the growth of KRASG12D-mutated ovarian and lung carcinomas in a manner dependent on CD8+ T cells. dIgA specific for IDH1R132H reduced colon cancer growth, demonstrating effective targeting of a cytoplasmic oncodriver not associated with surface receptors. dIgA targeting of KRASG12D restricted tumor growth more effectively than small-molecule KRASG12D inhibitors, supporting the potential of this approach for the treatment of human cancers.


Assuntos
Carcinoma , Imunoglobulina A , Humanos , Imunoglobulina A/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Citoplasma/metabolismo
3.
Blood Adv ; 7(18): 5586-5602, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37531660

RESUMO

The pathogenesis of cutaneous T-cell lymphoma (CTCL) remains unclear. Using single-cell RNA or T-cell receptor (TCR) sequencing of 32 619 CD3+CD4+ and CD26+/CD7+ and 29 932 CD3+CD4+ and CD26-/CD7- lymphocytes from the peripheral blood of 7 patients with CTCL, coupled to single-cell ATAC-sequencing of 26,411 CD3+CD4+ and CD26+/CD7+ and 33 841 CD3+CD4+ and CD26-/CD7- lymphocytes, we show that tumor cells in Sézary syndrome and mycosis fungoides (MF) exhibit different phenotypes and trajectories of differentiation. When compared to MF, Sézary cells exhibit narrower repertoires of TCRs and exhibit clonal enrichment. Surprisingly, we identified ≥200 mutations in hematopoietic stem cells from multiple patients with Sézary syndrome. Mutations in key oncogenes were also present in peripheral Sézary cells, which also showed the hallmarks of recent thymic egression. Together our data suggest that CTCL arises from mutated lymphocyte progenitors that acquire TCRs in the thymus, which complete their malignant transformation in the periphery.


Assuntos
Linfoma Cutâneo de Células T , Micose Fungoide , Síndrome de Sézary , Neoplasias Cutâneas , Humanos , Síndrome de Sézary/genética , Síndrome de Sézary/patologia , Dipeptidil Peptidase 4 , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Micose Fungoide/genética , Micose Fungoide/patologia , Linfoma Cutâneo de Células T/genética , Receptores de Antígenos de Linfócitos T
4.
Gynecol Oncol ; 173: 114-121, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37121178

RESUMO

OBJECTIVE: To demonstrate that shared antibody responses in endometriosis and endometriosis-associated ovarian cancer spontaneously antagonize malignant progression and can be leveraged to develop future immunotherapies. METHODS: B cells from cyopreserved clear cell ovarian carcinoma (CCC, n = 2), endometrioid ovarian carcinoma (EC, n = 2), and endometriomas (n = 2) were isolated, activated, and EBV-immortalized. Antibodies were purified from B cell supernatants and used for screening arrays containing most of the human proteome. Targets were prioritized based on accessibility (transmembrane or secreted proteins), expression in endometriosis and cancer, and concurrent IgA and IgG responses. We focused on antibodies targeting tumor-promoting syndecan binding protein (SDCBP) to demonstrate anti-tumor activity. Immunoblots and qPCR were performed to assess SDCBP expression in ovarian cancer and endometriosis cell lines and tumor samples. Recombinant IgG4 was generated using the variable heavy and light chains of dominant B cell receptors (BCRs) reacting against the extracellular domain of SDCBP, and used in in vivo studies in human CCC- and high-grade serous ovarian carcinoma (HGSOC)-bearing immunodeficient mice. RESULTS: Nine accessible proteins detected by both IgA and IgG were identified in all samples - including SDCBP, which is expressed in ovarian carcinomas of multiple histologies. Administration of α-SDCBP IgG4 in OVCAR3 (HGSOC), TOV21G and RMG-I (CCC) tumor-bearing mice significantly decreased tumor volume compared to control irrelevant IgG4. CONCLUSIONS: Spontaneous antibody responses exert suboptimal but measurable immune pressure against malignant progression in ovarian carcinomas. Using tumor-derived antibodies for developing novel immunotherapeutics warrants further investigation.


Assuntos
Adenocarcinoma de Células Claras , Carcinoma Endometrioide , Endometriose , Neoplasias Ovarianas , Humanos , Feminino , Animais , Camundongos , Neoplasias Ovarianas/patologia , Apoptose , Formação de Anticorpos , Linhagem Celular Tumoral , Carcinoma Epitelial do Ovário , Carcinoma Endometrioide/patologia , Imunoglobulina A/metabolismo , Adenocarcinoma de Células Claras/patologia , Sinteninas/metabolismo
5.
Semin Immunol ; 65: 101707, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36527759

RESUMO

Immuno-oncology has traditionally focused on the cellular arm of the adaptive immune response, while attributing tumor-promoting activity to humoral responses in tumor-bearing hosts. This view stems from mouse models that do not necessarily recapitulate the antibody response process consistently observed in most human cancers. In recent years, the field has reconsidered the coordinated action of T and B cell responses in the context of anti-tumor immunity, as in any other immune response. Thus, recent studies in human cancer identify B cell responses with better outcome, typically in association with superior T cell responses. An area of particular interest is tertiary lymphoid structures, where germinal centers produce isotype switched antibodies and B cells and T lymphocytes interact with other immune cell types. The presence of these lymphoid structures is associated with better immunotherapeutic responses and remain poorly understood. Here, we discuss recent discoveries on how coordination between humoral and cellular responses is required for effective immune pressure against malignant progression, providing a perspective on the role of tertiary lymphoid structures and interventions to elicit their formation in unresectable tumors.


Assuntos
Linfócitos B , Neoplasias , Linfócitos T , Estruturas Linfoides Terciárias , Animais , Humanos , Camundongos , Imunidade Adaptativa/imunologia , Linfócitos B/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Linfócitos T/imunologia , Estruturas Linfoides Terciárias/imunologia
6.
Cancer Immunol Immunother ; 72(6): 1445-1460, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36469096

RESUMO

Radiation therapy (RT) can prime and boost systemic anti-tumor effects via STING activation, resulting in enhanced tumor antigen presentation and antigen recognition by T cells. It is increasingly recognized that optimal anti-tumor immune responses benefit from coordinated cellular (T cell) and humoral (B cell) responses. However, the nature and functional relevance of the RT-induced immune response are controversial, beyond STING signaling, and agonistic interventions are lacking. Here, we show that B and CD4+ T cell accumulation at tumor beds in response to RT precedes the arrival of CD8+ T cells, and both cell types are absolutely required for abrogated tumor growth in non-irradiated tumors. Further, RT induces increased expression of 4-1BB (CD137) in both T and B cells; both in preclinical models and in a cohort of patients with small cell lung cancer treated with thoracic RT. Accordingly, the combination of RT and anti-41BB therapy leads to increased immune cell infiltration in the tumor microenvironment and significant abscopal effects. Thus, 4-1BB therapy enhances radiation-induced tumor-specific immune responses via coordinated B and T cell responses, thereby preventing malignant progression at unirradiated tumor sites. These findings provide a rationale for combining RT and 4-1bb therapy in future clinical trials.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Neoplasias/radioterapia , Imunoterapia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral , Ativação Linfocitária , Microambiente Tumoral
7.
Mol Cancer Ther ; 21(7): 1184-1194, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35499393

RESUMO

Although chimeric antigen receptor (CAR)-expressing T cells have proven success in hematologic malignancies, their effectiveness in solid tumors has been largely unsuccessful thus far. We found that some olfactory receptors are expressed in a variety of solid tumors of different histologic subtypes, with a limited pattern of expression in normal tissues. Quantification of OR2H1 expression by qRT-PCR and Western blot analysis of 17 normal tissues, 82 ovarian cancers of various histologies, eight non-small cell lung cancers (NSCLCs), and 17 breast cancers demonstrated widespread OR2H1 expression in solid epithelial tumors with expression in normal human tissues limited to the testis. CAR T cells recognizing the extracellular domain of the olfactory receptor OR2H1 were generated with a targeting motif identified through the screening of a phage display library and demonstrated OR2H1-specific cytotoxic killing in vitro and in vivo, using tumor cells with spontaneous expression of variable OR2H1 levels. Importantly, recombinant OR2H1 IgG generated with the VH/VL sequences of the CAR construct specifically detected OR2H1 protein signal in 60 human lung cancers, 40 ovarian carcinomas, and 73 cholangiocarcinomas, at positivity rates comparable with mRNA expression and without OR2H1 staining in 58 normal tissues. CRISPR/Cas9-mediated ablation of OR2H1 confirmed targeting specificity of the CAR and the tumor-promoting role of OR2H1 in glucose metabolism. Therefore, T cells redirected against OR2H1-expressing tumor cells represent a promising therapy against a broad range of epithelial cancers, likely with an admissible toxicity profile.


Assuntos
Neoplasias Pulmonares , Neoplasias Epiteliais e Glandulares , Neoplasias Ovarianas , Receptores Odorantes , Feminino , Humanos , Linhagem Celular Tumoral , Imunoterapia Adotiva , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Ovarianas/metabolismo , Receptores Odorantes/metabolismo , Linfócitos T
8.
Cancer Cell ; 40(5): 545-557.e13, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35427494

RESUMO

Despite repeated associations between T cell infiltration and outcome, human ovarian cancer remains poorly responsive to immunotherapy. We report that the hallmarks of tumor recognition in ovarian cancer-infiltrating T cells are primarily restricted to tissue-resident memory (TRM) cells. Single-cell RNA/TCR/ATAC sequencing of 83,454 CD3+CD8+CD103+CD69+ TRM cells and immunohistochemistry of 122 high-grade serous ovarian cancers shows that only progenitor (TCF1low) tissue-resident T cells (TRMstem cells), but not recirculating TCF1+ T cells, predict ovarian cancer outcome. TRMstem cells arise from transitional recirculating T cells, which depends on antigen affinity/persistence, resulting in oligoclonal, trogocytic, effector lymphocytes that eventually become exhausted. Therefore, ovarian cancer is indeed an immunogenic disease, but that depends on ∼13% of CD8+ tumor-infiltrating T cells (∼3% of CD8+ clonotypes), which are primed against high-affinity antigens and maintain waves of effector TRM-like cells. Our results define the signature of relevant tumor-reactive T cells in human ovarian cancer, which could be applicable to other tumors with unideal mutational burden.


Assuntos
Memória Imunológica , Neoplasias Ovarianas , Linfócitos T CD8-Positivos , Feminino , Humanos , Linfócitos do Interstício Tumoral , Células T de Memória
9.
Immunity ; 55(1): 115-128.e9, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35021053

RESUMO

The immune checkpoint receptor PD-1 on T follicular helper (Tfh) cells promotes Tfh:B cell interactions and appropriate positioning within tissues. Here, we examined the impact of regulation of PD-1 expression by the genomic organizer SATB1 on Tfh cell differentiation. Vaccination of CD4CreSatb1f/f mice enriched for antigen-specific Tfh cells, and TGF-ß-mediated repression of SATB1 enhanced Tfh differentiation of human T cells. Mechanistically, high Icos expression in Satb1-/- CD4+ T cells promoted Tfh cell differentiation by preventing T follicular regulatory cell skewing and resulted in increased isotype-switched B cell responses in vivo. Ovarian tumors in CD4CreSatb1f/f mice accumulated tumor antigen-specific, LIGHT+CXCL13+IL-21+ Tfh cells and tertiary lymphoid structures (TLS). TLS formation decreased tumor growth in a CD4+ T cell and CXCL13-dependent manner. The transfer of Tfh cells, but not naive CD4+ T cells, induced TLS at tumor beds and decreased tumor growth. Thus, TGF-ß-mediated silencing of Satb1 licenses Tfh cell differentiation, providing insight into the genesis of TLS within tumors.


Assuntos
Centro Germinativo/imunologia , Linfócitos do Interstício Tumoral/imunologia , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Estruturas Linfoides Terciárias/imunologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Diferenciação Celular , Regulação da Expressão Gênica , Inativação Gênica , Genótipo , Proteínas de Ligação à Região de Interação com a Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Fator de Crescimento Transformador beta/genética
10.
Cancer Res ; 82(5): 859-871, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34949671

RESUMO

Recent studies suggest that B cells could play an important role in the tumor microenvironment. However, the role of humoral responses in endometrial cancer remains insufficiently investigated. Using a cohort of 107 patients with different histological subtypes of endometrial carcinoma, we evaluated the role of coordinated humoral and cellular adaptive immune responses in endometrial cancer. Concomitant accumulation of T, B, and plasma cells at tumor beds predicted better survival. However, only B-cell markers corresponded with prolonged survival specifically in high-grade endometrioid type and serous tumors. Immune protection was associated with class-switched IgA and, to a lesser extent, IgG. Expressions of polymeric immunoglobulin receptor (pIgR) by tumor cells and its occupancy by IgA were superior predictors of outcome and correlated with defects in methyl-directed DNA mismatch repair. Mechanistically, pIgR-dependent, antigen-independent IgA occupancy drove activation of inflammatory pathways associated with IFN and TNF signaling in tumor cells, along with apoptotic and endoplasmic reticulum stress pathways, while thwarting DNA repair mechanisms. Together, these findings suggest that coordinated humoral and cellular immune responses, characterized by IgA:pIgR interactions in tumor cells, determine the progression of human endometrial cancer as well as the potential for effective immunotherapies. SIGNIFICANCE: This study provides new insights into the crucial role of humoral immunity in human endometrial cancer, providing a rationale for designing novel immunotherapies against this prevalent malignancy. See related commentary by Osorio and Zamarin, p. 766.


Assuntos
Neoplasias do Endométrio , Receptores de Imunoglobulina Polimérica , Linfócitos B/metabolismo , Neoplasias do Endométrio/patologia , Feminino , Humanos , Imunidade Humoral , Imunoglobulina A/metabolismo , Receptores de Imunoglobulina Polimérica/genética , Receptores de Imunoglobulina Polimérica/metabolismo , Microambiente Tumoral
11.
Nature ; 591(7850): 464-470, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536615

RESUMO

Most ovarian cancers are infiltrated by prognostically relevant activated T cells1-3, yet exhibit low response rates to immune checkpoint inhibitors4. Memory B cell and plasma cell infiltrates have previously been associated with better outcomes in ovarian cancer5,6, but the nature and functional relevance of these responses are controversial. Here, using 3 independent cohorts that in total comprise 534 patients with high-grade serous ovarian cancer, we show that robust, protective humoral responses are dominated by the production of polyclonal IgA, which binds to polymeric IgA receptors that are universally expressed on ovarian cancer cells. Notably, tumour B-cell-derived IgA redirects myeloid cells against extracellular oncogenic drivers, which causes tumour cell death. In addition, IgA transcytosis through malignant epithelial cells elicits transcriptional changes that antagonize the RAS pathway and sensitize tumour cells to cytolytic killing by T cells, which also contributes to hindering malignant progression. Thus, tumour-antigen-specific and -antigen-independent IgA responses antagonize the growth of ovarian cancer by governing coordinated tumour cell, T cell and B cell responses. These findings provide a platform for identifying targets that are spontaneously recognized by intratumoural B-cell-derived antibodies, and suggest that immunotherapies that augment B cell responses may be more effective than approaches that focus on T cells, particularly for malignancies that are resistant to checkpoint inhibitors.


Assuntos
Antígenos de Neoplasias/imunologia , Imunoglobulina A/imunologia , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Linfócitos T Citotóxicos/imunologia , Transcitose , Especificidade de Anticorpos , Antígenos CD/imunologia , Linhagem Celular , Progressão da Doença , Feminino , Humanos , Neoplasias Ovarianas/prevenção & controle , Receptores Fc/imunologia , Família de Moléculas de Sinalização da Ativação Linfocitária/imunologia , Transcitose/imunologia , Microambiente Tumoral/imunologia
12.
J Clin Invest ; 131(3)2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33270606

RESUMO

Cutaneous T cell lymphoma (CTCL) has a poorly understood etiology and no known cure. Using conditional knockout mice, we found that ablation of the genomic organizer special AT-rich sequence-binding protein 1 (Satb1) caused malignant transformation of mature, skin-homing, Notch-activated CD4+ and CD8+ T cells into progressively fatal lymphoma. Mechanistically, Satb1 restrained Stat5 phosphorylation and the expression of skin-homing chemokine receptors in mature T cells. Notably, methyltransferase-dependent epigenetic repression of SATB1 was universally found in human Sézary syndrome, but not in other peripheral T cell malignancies. H3K27 and H3K9 trimethylation occluded the SATB1 promoter in Sézary cells, while inhibition of SUV39H1/2 methyltransferases (unlike EZH2 inhibition) restored protective SATB1 expression and selectively abrogated the growth of primary Sézary cells more effectively than romidepsin. Therefore, inhibition of methyltransferases that silence SATB1 could address an unmet need for patients with mycosis fungoides/Sézary syndrome, a set of incurable diseases.


Assuntos
Inibidores Enzimáticos/farmacologia , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Metiltransferases/antagonistas & inibidores , Proteínas de Neoplasias , Síndrome de Sézary/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Linhagem Celular Tumoral , Humanos , Metiltransferases/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Síndrome de Sézary/metabolismo , Síndrome de Sézary/patologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
13.
Semin Immunol ; 49: 101419, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-33183950

RESUMO

Solid cancers progress from primordial lesions through complex interactions between tumor-promoting and anti-tumor immune cell types, ultimately leading to the orchestration of humoral and T cell adaptive immune responses, albeit in an immunosuppressive environment. B cells infiltrating most established tumors have been associated with a dual role: Some studies have associated antibodies produced by tumor-associated B cells with the promotion of regulatory activities on myeloid cells, and also with direct immunosuppression through the production of IL-10, IL-35 or TGF-ß. In contrast, recent studies in multiple human malignancies identify B cell responses with delayed malignant progression and coordinated T cell protective responses. This includes the elusive role of Tertiary Lymphoid Structures identified in many human tumors, where the function of B cells remains unknown. Here, we discuss emerging data on the dual role of B cell responses in the pathophysiology of human cancer, providing a perspective on future directions and possible novel interventions to restore the coordinated action of both branches of the adaptive immune response, with the goal of maximizing immunotherapeutic effectiveness.


Assuntos
Linfócitos B/imunologia , Imunidade Humoral , Neoplasias/etiologia , Animais , Linfócitos B/metabolismo , Biomarcadores , Citocinas/metabolismo , Gerenciamento Clínico , Suscetibilidade a Doenças , Humanos , Imunomodulação , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Microambiente Tumoral/imunologia
14.
Science ; 369(6506): 942-949, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32820120

RESUMO

Gamma delta (γδ) T cells infiltrate most human tumors, but current immunotherapies fail to exploit their in situ major histocompatibility complex-independent tumoricidal potential. Activation of γδ T cells can be elicited by butyrophilin and butyrophilin-like molecules that are structurally similar to the immunosuppressive B7 family members, yet how they regulate and coordinate αß and γδ T cell responses remains unknown. Here, we report that the butyrophilin BTN3A1 inhibits tumor-reactive αß T cell receptor activation by preventing segregation of N-glycosylated CD45 from the immune synapse. Notably, CD277-specific antibodies elicit coordinated restoration of αß T cell effector activity and BTN2A1-dependent γδ lymphocyte cytotoxicity against BTN3A1+ cancer cells, abrogating malignant progression. Targeting BTN3A1 therefore orchestrates cooperative killing of established tumors by αß and γδ T cells and may present a treatment strategy for tumors resistant to existing immunotherapies.


Assuntos
Antígenos CD/imunologia , Butirofilinas/antagonistas & inibidores , Butirofilinas/imunologia , Linfócitos Intraepiteliais/imunologia , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/terapia , Animais , Anticorpos Monoclonais/uso terapêutico , Antígenos CD/genética , Butirofilinas/genética , Feminino , Humanos , Imunoterapia/métodos , Camundongos , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Nature ; 562(7727): 423-428, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30305738

RESUMO

Tumours evade immune control by creating hostile microenvironments that perturb T cell metabolism and effector function1-4. However, it remains unclear how intra-tumoral T cells integrate and interpret metabolic stress signals. Here we report that ovarian cancer-an aggressive malignancy that is refractory to standard treatments and current immunotherapies5-8-induces endoplasmic reticulum stress and activates the IRE1α-XBP1 arm of the unfolded protein response9,10 in T cells to control their mitochondrial respiration and anti-tumour function. In T cells isolated from specimens collected from patients with ovarian cancer, upregulation of XBP1 was associated with decreased infiltration of T cells into tumours and with reduced IFNG mRNA expression. Malignant ascites fluid obtained from patients with ovarian cancer inhibited glucose uptake and caused N-linked protein glycosylation defects in T cells, which triggered IRE1α-XBP1 activation that suppressed mitochondrial activity and IFNγ production. Mechanistically, induction of XBP1 regulated the abundance of glutamine carriers and thus limited the influx of glutamine that is necessary to sustain mitochondrial respiration in T cells under glucose-deprived conditions. Restoring N-linked protein glycosylation, abrogating IRE1α-XBP1 activation or enforcing expression of glutamine transporters enhanced mitochondrial respiration in human T cells exposed to ovarian cancer ascites. XBP1-deficient T cells in the metastatic ovarian cancer milieu exhibited global transcriptional reprogramming and improved effector capacity. Accordingly, mice that bear ovarian cancer and lack XBP1 selectively in T cells demonstrate superior anti-tumour immunity, delayed malignant progression and increased overall survival. Controlling endoplasmic reticulum stress or targeting IRE1α-XBP1 signalling may help to restore the metabolic fitness and anti-tumour capacity of T cells in cancer hosts.


Assuntos
Endorribonucleases/metabolismo , Mitocôndrias/metabolismo , Neoplasias Ovarianas/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Proteína 1 de Ligação a X-Box/metabolismo , Sistemas de Transporte de Aminoácidos Básicos , Animais , Ascite/metabolismo , Respiração Celular , Progressão da Doença , Estresse do Retículo Endoplasmático , Feminino , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Glutamina/metabolismo , Glicosilação , Humanos , Interferon gama/biossíntese , Interferon gama/genética , Camundongos , Metástase Neoplásica , Transplante de Neoplasias , Neoplasias Ovarianas/patologia , Transdução de Sinais , Taxa de Sobrevida , Linfócitos T/metabolismo , Evasão Tumoral/imunologia , Resposta a Proteínas não Dobradas , Proteína 1 de Ligação a X-Box/biossíntese , Proteína 1 de Ligação a X-Box/deficiência
16.
J Leukoc Biol ; 103(5): 799-805, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29537705

RESUMO

Due to their cytotoxic activities, many anticancer drugs cause extensive damage to the intestinal mucosa and have antibiotic activities. Here, we show that cisplatin induces significant changes in the repertoire of intestinal commensal bacteria that exacerbate mucosal damage. Restoration of the microbiota through fecal-pellet gavage drives healing of cisplatin-induced intestinal damage. Bacterial translocation to the blood stream is correspondingly abrogated, resulting in a significant reduction in systemic inflammation, as evidenced by decreased serum IL-6 and reduced mobilization of granulocytes. Mechanistically, reversal of dysbiosis in response to fecal gavage results in the production of protective mucins and mobilization of CD11b+ myeloid cells to the intestinal mucosa, which promotes angiogenesis. Administration of Ruminococcus gnavus, a bacterial strain selectively depleted by cisplatin treatment, could only partially restore the integrity of the intestinal mucosa and reduce systemic inflammation, without measurable increases in the accumulation of mucin proteins. Together, our results indicate that reconstitution of the full repertoire of intestinal bacteria altered by cisplatin treatment accelerates healing of the intestinal epithelium and ameliorates systemic inflammation. Therefore, fecal microbiota transplant could paradoxically prevent life-threatening bacteremia in cancer patients treated with chemotherapy.


Assuntos
Cisplatino/farmacologia , Disbiose/terapia , Transplante de Microbiota Fecal , Intestinos/microbiologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Disbiose/mortalidade , Disbiose/patologia , Feminino , Microbioma Gastrointestinal , Intestinos/efeitos dos fármacos , Intestinos/patologia , Neoplasias Ovarianas/microbiologia , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/microbiologia , Neoplasias Peritoneais/patologia , Células Tumorais Cultivadas
17.
Front Immunol ; 8: 504, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28496447

RESUMO

INTRODUCTION: Many antitumor therapies induce apoptotic cell death in order to cause tumor regression. Paradoxically, apoptotic cells are also known to promote wound healing, cell proliferation, and tumor cell repopulation in multicellular organisms. We aimed to characterize the nature of the regenerative signals concentrated in the micromilieu of dead and dying cells. METHODS: Cultures of viable melanoma B16F10 cells, mouse fibroblasts, and primary human fibroblast-like synoviocytes (FLS) in the presence of dead and dying cells, their supernatants (SNs), or purified agonists and antagonists were used to evaluate the stimulation of proliferation. Viable cell quantification was performed by either flow cytometry of harvested cells or by crystal violet staining of adherent cells. High-performance liquid chromatography and liquid chromatography coupled with mass spectrometry of cell SNs were deployed to identify the nature of growth-promoting factors. Coimplantation of living cells in the presence of SNs collected from dead and dying cells and specific agonists was used to evaluate tumor growth in vivo. RESULTS: The stimulation of proliferation of few surviving cells by bystander dead cells was confirmed for melanoma cells, mouse fibroblasts, and primary FLS. We found that small soluble molecules present in the protein-free fraction of SNs of dead and dying cells were responsible for the promotion of proliferation. The nucleoside inosine released by dead and dying cells acting via adenosine receptors was identified as putative inducer of proliferation of surviving tumor cells after irradiation and heat treatment. CONCLUSION: Inosine released by dead and dying cells mediates tumor cell proliferation via purinergic receptors. Therapeutic strategies surmounting this pathway may help to reduce the rate of recurrence after radio- and chemotherapy.

18.
Immunity ; 46(1): 51-64, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28099864

RESUMO

Despite the importance of programmed cell death-1 (PD-1) in inhibiting T cell effector activity, the mechanisms regulating its expression remain poorly defined. We found that the chromatin organizer special AT-rich sequence-binding protein-1 (Satb1) restrains PD-1 expression induced upon T cell activation by recruiting a nucleosome remodeling deacetylase (NuRD) complex to Pdcd1 regulatory regions. Satb1 deficienct T cells exhibited a 40-fold increase in PD-1 expression. Tumor-derived transforming growth factor ß (Tgf-ß) decreased Satb1 expression through binding of Smad proteins to the Satb1 promoter. Smad proteins also competed with the Satb1-NuRD complex for binding to Pdcd1 enhancers, releasing Pdcd1 expression from Satb1-mediated repression, Satb1-deficient tumor-reactive T cells lost effector activity more rapidly than wild-type lymphocytes at tumor beds expressing PD-1 ligand (CD274), and these differences were abrogated by sustained CD274 blockade. Our findings suggest that Satb1 functions to prevent premature T cell exhaustion by regulating Pdcd1 expression upon T cell activation. Dysregulation of this pathway in tumor-infiltrating T cells results in diminished anti-tumor immunity.


Assuntos
Repressão Epigenética/imunologia , Regulação da Expressão Gênica/imunologia , Linfócitos do Interstício Tumoral/imunologia , Proteínas de Ligação à Região de Interação com a Matriz/biossíntese , Receptor de Morte Celular Programada 1/biossíntese , Animais , ELISPOT , Humanos , Imunoprecipitação , Ativação Linfocitária/imunologia , Proteínas de Ligação à Região de Interação com a Matriz/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias/imunologia , Neoplasias/metabolismo
19.
PLoS Negl Trop Dis ; 10(6): e0004786, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27347876

RESUMO

Transmission-blocking (TB) vaccines are considered an important tool for malaria control and elimination. Among all the antigens characterized as TB vaccines against Plasmodium vivax, the ookinete surface proteins Pvs28 and Pvs25 are leading candidates. These proteins likely originated by a gene duplication event that took place before the radiation of the known Plasmodium species to primates. We report an evolutionary genetic analysis of a worldwide sample of pvs28 and pvs25 alleles. Our results show that both genes display low levels of genetic polymorphism when compared to the merozoite surface antigens AMA-1 and MSP-1; however, both ookinete antigens can be as polymorphic as other merozoite antigens such as MSP-8 and MSP-10. We found that parasite populations in Asia and the Americas are geographically differentiated with comparable levels of genetic diversity and specific amino acid replacements found only in the Americas. Furthermore, the observed variation was mainly accumulated in the EGF2- and EGF3-like domains for P. vivax in both proteins. This pattern was shared by other closely related non-human primate parasites such as Plasmodium cynomolgi, suggesting that it could be functionally important. In addition, examination with a suite of evolutionary genetic analyses indicated that the observed patterns are consistent with positive natural selection acting on Pvs28 and Pvs25 polymorphisms. The geographic pattern of genetic differentiation and the evidence for positive selection strongly suggest that the functional consequences of the observed polymorphism should be evaluated during development of TBVs that include Pvs25 and Pvs28.


Assuntos
Vacinas Antimaláricas/imunologia , Malária Vivax/prevenção & controle , Malária Vivax/transmissão , Plasmodium vivax/genética , Proteínas de Protozoários/genética , Evolução Molecular , Regulação da Expressão Gênica , Haplótipos , Humanos , Malária Vivax/parasitologia , Modelos Moleculares , Polimorfismo Genético , Conformação Proteica , Proteínas de Protozoários/metabolismo , Seleção Genética
20.
Front Immunol ; 6: 588, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26635802

RESUMO

The immunogenicity of malignant cells has recently been acknowledged as a critical determinant of efficacy in cancer therapy. Thus, besides developing direct immunostimulatory regimens, including dendritic cell-based vaccines, checkpoint-blocking therapies, and adoptive T-cell transfer, researchers have started to focus on the overall immunobiology of neoplastic cells. It is now clear that cancer cells can succumb to some anticancer therapies by undergoing a peculiar form of cell death that is characterized by an increased immunogenic potential, owing to the emission of the so-called "damage-associated molecular patterns" (DAMPs). The emission of DAMPs and other immunostimulatory factors by cells succumbing to immunogenic cell death (ICD) favors the establishment of a productive interface with the immune system. This results in the elicitation of tumor-targeting immune responses associated with the elimination of residual, treatment-resistant cancer cells, as well as with the establishment of immunological memory. Although ICD has been characterized with increased precision since its discovery, several questions remain to be addressed. Here, we summarize and tabulate the main molecular, immunological, preclinical, and clinical aspects of ICD, in an attempt to capture the essence of this phenomenon, and identify future challenges for this rapidly expanding field of investigation.

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