RESUMO
Immunosuppressive macrophages restrict anti-cancer immunity in glioblastoma (GBM). Here, we studied the contribution of microglia (MGs) and monocyte-derived macrophages (MDMs) to immunosuppression and mechanisms underlying their regulatory function. MDMs outnumbered MGs at late tumor stages and suppressed T cell activity. Molecular and functional analysis identified a population of glycolytic MDM expressing GLUT1 with potent immunosuppressive activity. GBM-derived factors promoted high glycolysis, lactate, and interleukin-10 (IL-10) production in MDMs. Inhibition of glycolysis or lactate production in MDMs impaired IL-10 expression and T cell suppression. Mechanistically, intracellular lactate-driven histone lactylation promoted IL-10 expression, which was required to suppress T cell activity. GLUT1 expression on MDMs was induced downstream of tumor-derived factors that activated the PERK-ATF4 axis. PERK deletion in MDM abrogated histone lactylation, led to the accumulation of intratumoral T cells and tumor growth delay, and, in combination with immunotherapy, blocked GBM progression. Thus, PERK-driven glucose metabolism promotes MDM immunosuppressive activity via histone lactylation.
Assuntos
Glioblastoma , Glucose , Histonas , Macrófagos , Glioblastoma/imunologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Animais , Histonas/metabolismo , Camundongos , Macrófagos/imunologia , Macrófagos/metabolismo , Glucose/metabolismo , Humanos , Linhagem Celular Tumoral , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 1/genética , Interleucina-10/metabolismo , Glicólise , Microglia/metabolismo , Microglia/imunologia , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia , Linfócitos T/metabolismo , Tolerância ImunológicaRESUMO
Signaling through Notch receptors intrinsically regulates tumor cell development and growth. Here, we studied the role of the Notch ligand Jagged2 on immune evasion in non-small cell lung cancer (NSCLC). Higher expression of JAG2 in NSCLC negatively correlated with survival. In NSCLC pre-clinical models, deletion of Jag2, but not Jag1, in cancer cells attenuated tumor growth and activated protective anti-tumor T cell responses. Jag2-/- lung tumors exhibited higher frequencies of macrophages that expressed immunostimulatory mediators and triggered T cell-dependent anti-tumor immunity. Mechanistically, Jag2 ablation promoted Nr4a-mediated induction of Notch ligands DLL1/4 on cancer cells. DLL1/4-initiated Notch1/2 signaling in macrophages induced the expression of transcription factor IRF4 and macrophage immunostimulatory functionality. IRF4 expression was required for the anti-tumor effects of Jag2 deletion in lung tumors. Antibody targeting of Jagged2 inhibited tumor growth and activated IRF4-driven macrophage-mediated anti-tumor immunity. Thus, Jagged2 orchestrates immunosuppressive systems in NSCLC that can be overcome to incite macrophage-mediated anti-tumor immunity.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Fatores Reguladores de Interferon , Proteína Jagged-2 , Neoplasias Pulmonares , Camundongos Knockout , Macrófagos Associados a Tumor , Animais , Humanos , Camundongos , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Fatores Reguladores de Interferon/metabolismo , Fatores Reguladores de Interferon/genética , Proteína Jagged-1/metabolismo , Proteína Jagged-1/genética , Proteína Jagged-2/metabolismo , Proteína Jagged-2/genética , Proteína Jagged-2/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Receptor Notch1/metabolismo , Receptor Notch1/genética , Receptores Notch/metabolismo , Transdução de Sinais , Evasão Tumoral/imunologia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismoRESUMO
Dietary soluble fibers are fermented by gut bacteria into short-chain fatty acids (SCFA), which are considered broadly health-promoting. Accordingly, consumption of such fibers ameliorates metabolic syndrome. However, incorporating soluble fiber inulin, but not insoluble fiber, into a compositionally defined diet, induced icteric hepatocellular carcinoma (HCC). Such HCC was microbiota-dependent and observed in multiple strains of dysbiotic mice but not in germ-free nor antibiotics-treated mice. Furthermore, consumption of an inulin-enriched high-fat diet induced both dysbiosis and HCC in wild-type (WT) mice. Inulin-induced HCC progressed via early onset of cholestasis, hepatocyte death, followed by neutrophilic inflammation in liver. Pharmacologic inhibition of fermentation or depletion of fermenting bacteria markedly reduced intestinal SCFA and prevented HCC. Intervening with cholestyramine to prevent reabsorption of bile acids also conferred protection against such HCC. Thus, its benefits notwithstanding, enrichment of foods with fermentable fiber should be approached with great caution as it may increase risk of HCC.
Assuntos
Carcinoma Hepatocelular/etiologia , Colestase/complicações , Fibras na Dieta/metabolismo , Disbiose/complicações , Fermentação , Microbioma Gastrointestinal , Neoplasias Hepáticas/etiologia , Animais , Carcinoma Hepatocelular/microbiologia , Linhagem Celular Tumoral , Colestase/microbiologia , Dieta Hiperlipídica/efeitos adversos , Disbiose/microbiologia , Inulina/efeitos adversos , Neoplasias Hepáticas/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Antigen stimulation (signal 1) triggers B cell proliferation and primes B cells to recruit, engage and respond to T cell help (signal 2). Failure to receive signal 2 within a defined time window results in B cell apoptosis, yet the mechanisms that enforce dependence on co-stimulation are incompletely understood. Nr4a1-3 encode a small family of orphan nuclear receptors that are rapidly induced by B cell antigen receptor stimulation. Here, we show that Nr4a1 and Nr4a3 play partially redundant roles to restrain B cell responses to antigen in the absence of co-stimulation and do so, in part, by repressing the expression of BATF and, consequently, MYC. The NR4A family also restrains B cell access to T cell help by repressing expression of the T cell chemokines CCL3 and CCL4, as well as CD86 and ICAM1. Such NR4A-mediated regulation plays a role specifically under conditions of competition for limiting T cell help.
Assuntos
Linfócitos B/imunologia , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Comunicação Celular , Proliferação de Células , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Imunidade Humoral , Imunomodulação , Ativação Linfocitária , Camundongos , Camundongos Knockout , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Receptores de Antígenos de Linfócitos B/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Receptores dos Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/metabolismo , Transdução de SinaisRESUMO
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/metabolismoRESUMO
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/genéticaRESUMO
Dendritic cells (DCs) are required to initiate and sustain T cell-dependent anti-cancer immunity. However, tumors often evade immune control by crippling normal DC function. The endoplasmic reticulum (ER) stress response factor XBP1 promotes intrinsic tumor growth directly, but whether it also regulates the host anti-tumor immune response is not known. Here we show that constitutive activation of XBP1 in tumor-associated DCs (tDCs) drives ovarian cancer (OvCa) progression by blunting anti-tumor immunity. XBP1 activation, fueled by lipid peroxidation byproducts, induced a triglyceride biosynthetic program in tDCs leading to abnormal lipid accumulation and subsequent inhibition of tDC capacity to support anti-tumor T cells. Accordingly, DC-specific XBP1 deletion or selective nanoparticle-mediated XBP1 silencing in tDCs restored their immunostimulatory activity in situ and extended survival by evoking protective type 1 anti-tumor responses. Targeting the ER stress response should concomitantly inhibit tumor growth and enhance anti-cancer immunity, thus offering a unique approach to cancer immunotherapy.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Células Dendríticas/patologia , Estresse do Retículo Endoplasmático , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Fatores de Transcrição/metabolismo , Animais , Feminino , Humanos , Peroxidação de Lipídeos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fatores de Transcrição de Fator Regulador X , Linfócitos T/imunologia , Proteína 1 de Ligação a X-BoxRESUMO
Mounting effective immunity against pathogens and tumours relies on the successful metabolic programming of T cells by extracellular fatty acids1-3. Fatty-acid-binding protein 5 (FABP5) has a key role in this process by coordinating the efficient import and trafficking of lipids that fuel mitochondrial respiration to sustain the bioenergetic requirements of protective CD8+ T cells4,5. However, the mechanisms that govern this immunometabolic axis remain unexplored. Here we report that the cytoskeletal organizer transgelin 2 (TAGLN2) is necessary for optimal fatty acid uptake, mitochondrial respiration and anticancer function in CD8+ T cells. TAGLN2 interacts with FABP5 to facilitate its cell surface localization and function in activated CD8+ T cells. Analyses of ovarian cancer specimens revealed that endoplasmic reticulum (ER) stress responses induced by the tumour microenvironment repress TAGLN2 in infiltrating CD8+ T cells, thereby enforcing their dysfunctional state. Restoring TAGLN2 expression in ER-stressed CD8+ T cells increased their lipid uptake, mitochondrial respiration and cytotoxic capacity. Accordingly, chimeric antigen receptor T cells overexpressing TAGLN2 bypassed the detrimental effects of tumour-induced ER stress and demonstrated therapeutic efficacy in mice with metastatic ovarian cancer. Our study establishes the role of cytoskeletal TAGLN2 in T cell lipid metabolism and highlights the potential to enhance cellular immunotherapy in solid malignancies by preserving the TAGLN2-FABP5 axis.
RESUMO
The primary mechanisms supporting immunoregulatory polarization of myeloid cells upon infiltration into tumors remain largely unexplored. Elucidation of these signals could enable better strategies to restore protective anti-tumor immunity. Here, we investigated the role of the intrinsic activation of the PKR-like endoplasmic reticulum (ER) kinase (PERK) in the immunoinhibitory actions of tumor-associated myeloid-derived suppressor cells (tumor-MDSCs). PERK signaling increased in tumor-MDSCs, and its deletion transformed MDSCs into myeloid cells that activated CD8+ T cell-mediated immunity against cancer. Tumor-MDSCs lacking PERK exhibited disrupted NRF2-driven antioxidant capacity and impaired mitochondrial respiratory homeostasis. Moreover, reduced NRF2 signaling in PERK-deficient MDSCs elicited cytosolic mitochondrial DNA elevation and, consequently, STING-dependent expression of anti-tumor type I interferon. Reactivation of NRF2 signaling, conditional deletion of STING, or blockade of type I interferon receptor I restored the immunoinhibitory potential of PERK-ablated MDSCs. Our findings demonstrate the pivotal role of PERK in tumor-MDSC functionality and unveil strategies to reprogram immunosuppressive myelopoiesis in tumors to boost cancer immunotherapy.
Assuntos
Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Epitelial do Ovário/imunologia , Regulação Neoplásica da Expressão Gênica , Melanoma Experimental/imunologia , Proteínas de Membrana/imunologia , Neoplasias Cutâneas/imunologia , eIF-2 Quinase/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Carcinoma Epitelial do Ovário/patologia , Feminino , Humanos , Terapia de Imunossupressão , Interferon-alfa/genética , Interferon-alfa/imunologia , Interferon beta/genética , Interferon beta/imunologia , Masculino , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/patologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/imunologia , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Resposta a Proteínas não Dobradas/imunologia , eIF-2 Quinase/deficiência , eIF-2 Quinase/genéticaRESUMO
Globally, cancer is the second leading cause of death, with numbers greatly exceeding those for human immunodeficiency virus/acquired immunodeficiency syndrome, tuberculosis, and malaria combined. Limited access to timely diagnosis, to affordable, effective treatment, and to high-quality care are just some of the factors that lead to disparities in cancer survival between countries and within countries. In this article, the authors consider various factors that prevent access to cancer medicines (particularly access to essential cancer medicines). Even if an essential cancer medicine is included on a national medicines list, cost might preclude its use, it might be prescribed or used inappropriately, weak infrastructure might prevent it being accessed by those who could benefit, or quality might not be guaranteed. Potential strategies to address the access problems are discussed, including universal health coverage for essential cancer medicines, fairer methods for pricing cancer medicines, reducing development costs, optimizing regulation, and improving reliability in the global supply chain. Optimizing schedules for cancer therapy could reduce not only costs, but also adverse events, and improve access. More and better biomarkers are required to target patients who are most likely to benefit from cancer medicines. The optimum use of cancer medicines depends on the effective delivery of several services allied to oncology (including laboratory, imaging, surgery, and radiotherapy). Investment is necessary in all aspects of cancer care, from these supportive services to technologies, and the training of health care workers and other staff.
Assuntos
Acessibilidade aos Serviços de Saúde/tendências , Neoplasias/terapia , Qualidade da Assistência à Saúde , Terapia Combinada/tendências , HumanosRESUMO
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/imunologiaRESUMO
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/imunologiaRESUMO
Sirtuin 7 (SIRT7) is a member of the mammalian family of nicotinamide adenine dinucleotide (NAD+)-dependent histone/protein deacetylases, known as sirtuins. It acts as a potent oncogene in numerous malignancies, but the molecular mechanisms employed by SIRT7 to sustain lung cancer progression remain largely uncharacterized. We demonstrate that SIRT7 exerts oncogenic functions in lung cancer cells by destabilizing the tumor suppressor alternative reading frame (ARF). SIRT7 directly interacts with ARF and prevents binding of ARF to nucleophosmin, thereby promoting proteasomal-dependent degradation of ARF. We show that SIRT7-mediated degradation of ARF increases expression of protumorigenic genes and stimulates proliferation of non-small-cell lung cancer (NSCLC) cells both in vitro and in vivo in a mouse xenograft model. Bioinformatics analysis of transcriptome data from human lung adenocarcinomas revealed a correlation between SIRT7 expression and increased activity of genes normally repressed by ARF. We propose that disruption of SIRT7-ARF signaling stabilizes ARF and thus attenuates cancer cell proliferation, offering a strategy to mitigate NSCLC progression.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Proliferação de Células , Progressão da Doença , Neoplasias Pulmonares , Sirtuínas , Humanos , Sirtuínas/metabolismo , Sirtuínas/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Regulação Neoplásica da Expressão Gênica , Linhagem Celular TumoralRESUMO
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/metabolismoRESUMO
The MHYT domain, identified over two decades ago for its potential to detect diatomic gases like CO, O2 or NO, has awaited experimental validation as a protein sensory domain. Here, we characterize the MHYT domain-containing transcriptional regulator CoxC, which governs the expression of the cox genes responsible for aerobic CO oxidation in the carboxidotrophic bacterium Afipia carboxidovorans OM5. The C-terminal LytTR-type DNA-binding domain of CoxC binds to an operator region consisting of three direct repeats sequences overlapping the -35 box at the target PcoxB promoter, which is consistent with the role of CoxC as a specific transcriptional repressor of the cox genes. Notably, the N-terminal transmembrane MHYT domain endows CoxC with the ability to sense CO as an effector molecule, as demonstrated by the relief of CoxC-mediated repression and binding to the PcoxB promoter upon CO exposure. Furthermore, copper serves as the essential divalent cation for the interaction of CO with CoxC, thereby confirming previous hypothesis regarding the role of copper in the gas-sensing mechanism of MHYT domains. CoxC represents the prototype of a novel subfamily of single-component LytTR transcriptional regulators, characterized by the fusion of a DNA-binding domain with a membrane-bound MHYT sensor domain.
Assuntos
Proteínas de Bactérias , Monóxido de Carbono , Regulação Bacteriana da Expressão Gênica , Regiões Promotoras Genéticas , Monóxido de Carbono/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Domínios Proteicos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Cobre/metabolismo , Ligação Proteica , Sítios de Ligação , Transcrição Gênica , Regiões Operadoras GenéticasRESUMO
Exposure to stressful life events increases the risk for psychiatric disorders. Mechanistic insight into the genetic factors moderating the impact of stress can increase our understanding of disease processes. Here, we test 3,662 single nucleotide polymorphisms (SNPs) from preselected expression quantitative trait loci in massively parallel reporter assays to identify genetic variants that modulate the activity of regulatory elements sensitive to glucocorticoids, important mediators of the stress response. Of the tested SNP sequences, 547 were located in glucocorticoid-responsive regulatory elements of which 233 showed allele-dependent activity. Transcripts regulated by these functional variants were enriched for those differentially expressed in psychiatric disorders in the postmortem brain. Phenome-wide Mendelian randomization analysis in 4,439 phenotypes revealed potentially causal associations specifically in neurobehavioral traits, including major depression and other psychiatric disorders. Finally, a functional gene score derived from these variants was significantly associated with differences in the physiological stress response, suggesting that these variants may alter disease risk by moderating the individual set point of the stress response.
Assuntos
Glucocorticoides , Transtornos Mentais , Humanos , Ensaios de Triagem em Larga Escala , Sequências Reguladoras de Ácido Nucleico , Locos de Características Quantitativas , Transtornos Mentais/genética , Polimorfismo de Nucleotídeo Único , Estudo de Associação Genômica Ampla , Predisposição Genética para DoençaRESUMO
BACKGROUND: PHERGain was designed to assess the feasibility, safety, and efficacy of a chemotherapy-free treatment based on a dual human epidermal growth factor receptor 2 (HER2) blockade with trastuzumab and pertuzumab in patients with HER2-positive early breast cancer (EBC). It used an 18fluorine-fluorodeoxyglucose-PET-based, pathological complete response (pCR)-adapted strategy. METHODS: PHERGain was a randomised, open-label, phase 2 trial that took place in 45 hospitals in seven European countries. It randomly allocated patients in a 1:4 ratio with centrally confirmed, HER2-positive, stage I-IIIA invasive, operable breast cancer with at least one PET-evaluable lesion to either group A, where patients received docetaxel (75 mg/m2, intravenous), carboplatin (area under the curve 6 mg/mL per min, intravenous), trastuzumab (600 mg fixed dose, subcutaneous), and pertuzumab (840 mg loading dose followed by 420 mg maintenance doses, intravenous; TCHP), or group B, where patients received trastuzumab and pertuzumab with or without endocrine therapy, every 3 weeks. Random allocation was stratified by hormone receptor status. Centrally reviewed PET was conducted at baseline and after two treatment cycles. Patients in group B were treated according to on-treatment PET results. Patients in group B who were PET-responders continued with trastuzumab and pertuzumab with or without endocrine therapy for six cycles, while PET-non-responders were switched to receive six cycles of TCHP. After surgery, patients in group B who were PET-responders who did not achieve a pCR received six cycles of TCHP, and all patients completed up to 18 cycles of trastuzumab and pertuzumab. The primary endpoints were pCR in patients who were group B PET-responders after two treatment cycles (the results for which have been reported previously) and 3-year invasive disease-free survival (iDFS) in patients in group B. The study is registered with ClinicalTrials.gov (NCT03161353) and is ongoing. FINDINGS: Between June 26, 2017, and April 24, 2019, a total of 356 patients were randomly allocated (71 patients in group A and 285 patients in group B), and 63 (89%) and 267 (94%) patients proceeded to surgery in groups A and B, respectively. At this second analysis (data cutoff: Nov 4, 2022), the median duration of follow-up was 43·3 months (range 0·0-63·0). In group B, the 3-year iDFS rate was 94·8% (95% CI 91·4-97·1; p=0·001), meeting the primary endpoint. No new safety signals were identified. Treatment-related adverse events and serious adverse events (SAEs) were numerically higher in patients allocated to group A than to group B (grade ≥3 62% vs 33%; SAEs 28% vs 14%). Group B PET-responders with pCR presented the lowest incidence of treatment-related grade 3 or higher adverse events (1%) without any SAEs. INTERPRETATION: Among HER2-positive EBC patients, a PET-based, pCR-adapted strategy was associated with an excellent 3-year iDFS. This strategy identified about a third of patients who had HER2-positive EBC who could safely omit chemotherapy. FUNDING: F Hoffmann-La Roche.
Assuntos
Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias da Mama , Docetaxel , Fluordesoxiglucose F18 , Receptor ErbB-2 , Trastuzumab , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Pessoa de Meia-Idade , Trastuzumab/uso terapêutico , Trastuzumab/administração & dosagem , Receptor ErbB-2/metabolismo , Docetaxel/uso terapêutico , Docetaxel/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Adulto , Intervalo Livre de Doença , Idoso , Tomografia por Emissão de Pósitrons/métodos , Carboplatina/administração & dosagem , Carboplatina/uso terapêutico , Compostos RadiofarmacêuticosRESUMO
BACKGROUND: In an interim analysis of this phase 3 trial, the addition of pembrolizumab to chemotherapy resulted in longer progression-free survival than chemotherapy alone among patients with advanced triple-negative breast cancer whose tumors expressed programmed death ligand 1 (PD-L1) with a combined positive score (CPS; the number of PD-L1-staining tumor cells, lymphocytes, and macrophages, divided by the total number of viable tumor cells, multiplied by 100) of 10 or more. The results of the final analysis of overall survival have not been reported. METHODS: We randomly assigned patients with previously untreated locally recurrent inoperable or metastatic triple-negative breast cancer in a 2:1 ratio to receive pembrolizumab (200 mg) every 3 weeks plus the investigator's choice of chemotherapy (nanoparticle albumin-bound paclitaxel, paclitaxel, or gemcitabine-carboplatin) or placebo plus chemotherapy. The primary end points were progression-free survival (reported previously) and overall survival among patients whose tumors expressed PD-L1 with a CPS of 10 or more (the CPS-10 subgroup), among patients whose tumors expressed PD-L1 with a CPS of 1 or more (the CPS-1 subgroup), and in the intention-to-treat population. Safety was also assessed. RESULTS: A total of 847 patients underwent randomization: 566 were assigned to the pembrolizumab-chemotherapy group, and 281 to the placebo-chemotherapy group. The median follow-up was 44.1 months. In the CPS-10 subgroup, the median overall survival was 23.0 months in the pembrolizumab-chemotherapy group and 16.1 months in the placebo-chemotherapy group (hazard ratio for death, 0.73; 95% confidence interval [CI], 0.55 to 0.95; two-sided P = 0.0185 [criterion for significance met]); in the CPS-1 subgroup, the median overall survival was 17.6 and 16.0 months in the two groups, respectively (hazard ratio, 0.86; 95% CI, 0.72 to 1.04; two-sided P = 0.1125 [not significant]); and in the intention-to-treat population, the median overall survival was 17.2 and 15.5 months, respectively (hazard ratio, 0.89; 95% CI, 0.76 to 1.05 [significance not tested]). Adverse events of grade 3, 4, or 5 that were related to the trial regimen occurred in 68.1% of the patients in the pembrolizumab-chemotherapy group and in 66.9% in the placebo-chemotherapy group, including death in 0.4% of the patients in the pembrolizumab-chemotherapy group and in no patients in the placebo-chemotherapy group. CONCLUSIONS: Among patients with advanced triple-negative breast cancer whose tumors expressed PD-L1 with a CPS of 10 or more, the addition of pembrolizumab to chemotherapy resulted in significantly longer overall survival than chemotherapy alone. (Funded by Merck Sharp and Dohme; KEYNOTE-355 ClinicalTrials.gov number, NCT02819518.).
Assuntos
Anticorpos Monoclonais Humanizados , Inibidores de Checkpoint Imunológico , Neoplasias de Mama Triplo Negativas , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/biossíntese , Antígeno B7-H1/genética , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismoRESUMO
A continuum from stem to transit-amplifying to a differentiated cell state is a common theme in multicellular organisms. In the plant root apical meristem (RAM), transit-amplifying cells are organized into two domains: cells from the proliferation domain (PD) are displaced to the transition domain (TD), suggesting that both domains are necessarily coupled. Here, we show that in the Arabidopsis thaliana mto2-2 mutant, in which threonine (Thr) synthesis is affected, the RAM lacks the PD. Through a combination of cell length profile analysis, mathematical modeling and molecular markers, we establish that the PD and TD can be uncoupled. Remarkably, although the RAM of mto2-2 is represented solely by the TD, the known factors of RAM maintenance and auxin signaling are expressed in the mutant. Mathematical modeling predicts that the stem cell niche depends on Thr metabolism and that, when disturbed, the normal continuum of cell states becomes aborted.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Meristema/genética , Meristema/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Treonina/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Mutação/genética , Proliferação de Células/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
SUMMARY: We introduce a unified Python package for the prediction of protein biophysical properties, streamlining previous tools developed by the Bio2Byte research group. This suite facilitates comprehensive assessments of protein characteristics, incorporating predictors for backbone and sidechain dynamics, local secondary structure propensities, early folding, long disorder, beta-sheet aggregation, and fused in sarcoma (FUS)-like phase separation. Our package significantly eases the integration and execution of these tools, enhancing accessibility for both computational and experimental researchers. AVAILABILITY AND IMPLEMENTATION: The suite is available on the Python Package Index (PyPI): https://pypi.org/project/b2bTools/ and Bioconda: https://bioconda.github.io/recipes/b2btools/README.html for Linux and macOS systems, with Docker images hosted on Biocontainers: https://quay.io/repository/biocontainers/b2btools?tab=tags&tag=latest and Docker Hub: https://hub.docker.com/u/bio2byte. Online deployments are available on Galaxy Europe: https://usegalaxy.eu/root?tool_id=b2btools_single_sequence and our online server: https://bio2byte.be/b2btools/. The source code can be found at https://bitbucket.org/bio2byte/b2btools_releases.