Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
J Immunol ; 197(7): 2816-27, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27559045

RESUMO

Con A hepatitis is regarded as a T cell-mediated model of acute liver injury. Mincle is a C-type lectin receptor that is critical in the immune response to mycobacteria and fungi but does not have a well-defined role in preclinical models of non-pathogen-mediated inflammation. Because Mincle can ligate the cell death ligand SAP130, we postulated that Mincle signaling drives intrahepatic inflammation and liver injury in Con A hepatitis. Acute liver injury was assessed in the murine Con A hepatitis model using C57BL/6, Mincle(-/-), and Dectin-1(-/-) mice. The role of C/EBPß and hypoxia-inducible factor-1α (HIF-1α) signaling was assessed using selective inhibitors. We found that Mincle was highly expressed in hepatic innate inflammatory cells and endothelial cells in both mice and humans. Furthermore, sterile Mincle ligands and Mincle signaling intermediates were increased in the murine liver in Con A hepatitis. Most significantly, Mincle deletion or blockade protected against Con A hepatitis, whereas Mincle ligation exacerbated disease. Bone marrow chimeric and adoptive transfer experiments suggested that Mincle signaling in infiltrating myeloid cells dictates disease phenotype. Conversely, signaling via other C-type lectin receptors did not alter disease course. Mechanistically, we found that Mincle blockade decreased the NF-κß-related signaling intermediates C/EBPß and HIF-1α, both of which are necessary in macrophage-mediated inflammatory responses. Accordingly, Mincle deletion lowered production of nitrites in Con A hepatitis and inhibition of both C/EBPß and HIF-1α reduced the severity of liver disease. Our work implicates a novel innate immune driver of Con A hepatitis and, more broadly, suggests a potential role for Mincle in diseases governed by sterile inflammation.


Assuntos
Concanavalina A/imunologia , Hepatite/imunologia , Lectinas Tipo C/imunologia , Proteínas de Membrana/imunologia , Transdução de Sinais/imunologia , Animais , Modelos Animais de Doenças , Hepatite/metabolismo , Humanos , Inflamação/imunologia , Lectinas Tipo C/deficiência , Leucócitos Mononucleares , Masculino , Proteínas de Membrana/deficiência , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nitritos/metabolismo
2.
Cancer Discov ; 12(8): 1922-1941, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35658124

RESUMO

Activated B cell-like diffuse large B-cell lymphomas (ABC-DLBCL) have unfavorable outcomes and chronic activation of CARD11-BCL10-MALT1 (CBM) signal amplification complexes that form due to polymerization of BCL10 subunits, which is affected by recurrent somatic mutations in ABC-DLBCLs. Herein, we show that BCL10 mutants fall into at least two functionally distinct classes: missense mutations of the BCL10 CARD domain and truncation of its C-terminal tail. Truncating mutations abrogated a motif through which MALT1 inhibits BCL10 polymerization, trapping MALT1 in its activated filament-bound state. CARD missense mutations enhanced BCL10 filament formation, forming glutamine network structures that stabilize BCL10 filaments. Mutant forms of BCL10 were less dependent on upstream CARD11 activation and thus manifested resistance to BTK inhibitors, whereas BCL10 truncating but not CARD mutants were hypersensitive to MALT1 inhibitors. Therefore, BCL10 mutations are potential biomarkers for BTK inhibitor resistance in ABC-DLBCL, and further precision can be achieved by selecting therapy based on specific biochemical effects of distinct mutation classes. SIGNIFICANCE: ABC-DLBCLs feature frequent mutations of signaling mediators that converge on the CBM complex. We use structure-function approaches to reveal that BCL10 mutations fall into two distinct biochemical classes. Both classes confer resistance to BTK inhibitors, whereas BCL10 truncations confer hyperresponsiveness to MALT1 inhibitors, providing a road map for precision therapies in ABC-DLBCLs. See related commentary by Phelan and Oellerich, p. 1844. This article is highlighted in the In This Issue feature, p. 1825.


Assuntos
Proteína 10 de Linfoma CCL de Células B , Linfoma Difuso de Grandes Células B , Proteína 10 de Linfoma CCL de Células B/genética , Proteínas Adaptadoras de Sinalização CARD/genética , Guanilato Ciclase/genética , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/genética , Mutação , Transdução de Sinais
3.
Cancer Cell ; 37(5): 655-673.e11, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32396861

RESUMO

Follicular lymphomas (FLs) are slow-growing, indolent tumors containing extensive follicular dendritic cell (FDC) networks and recurrent EZH2 gain-of-function mutations. Paradoxically, FLs originate from highly proliferative germinal center (GC) B cells with proliferation strictly dependent on interactions with T follicular helper cells. Herein, we show that EZH2 mutations initiate FL by attenuating GC B cell requirement for T cell help and driving slow expansion of GC centrocytes that become enmeshed with and dependent on FDCs. By impairing T cell help, mutant EZH2 prevents induction of proliferative MYC programs. Thus, EZH2 mutation fosters malignant transformation by epigenetically reprograming B cells to form an aberrant immunological niche that reflects characteristic features of human FLs, explaining how indolent tumors arise from GC B cells.


Assuntos
Linfócitos B/imunologia , Transformação Celular Neoplásica/imunologia , Reprogramação Celular , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Linfoma de Células B/imunologia , Linfoma Folicular/imunologia , Mutação , Animais , Linfócitos B/metabolismo , Linfócitos B/patologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Feminino , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Centro Germinativo/patologia , Humanos , Linfoma de Células B/genética , Linfoma de Células B/patologia , Linfoma Folicular/genética , Linfoma Folicular/patologia , Camundongos , Camundongos Endogâmicos C57BL
4.
Nat Commun ; 10(1): 5151, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723131

RESUMO

Pancreatic ductal adenocarcinoma (PDA) is a lethal malignancy with limited treatment options. Although metabolic reprogramming is a hallmark of many cancers, including PDA, previous attempts to target metabolic changes therapeutically have been stymied by drug toxicity and tumour cell plasticity. Here, we show that PDA cells engage an eIF4F-dependent translation program that supports redox and central carbon metabolism. Inhibition of the eIF4F subunit, eIF4A, using the synthetic rocaglate CR-1-31-B (CR-31) reduced the viability of PDA organoids relative to their normal counterparts. In vivo, CR-31 suppresses tumour growth and extends survival of genetically-engineered murine models of PDA. Surprisingly, inhibition of eIF4A also induces glutamine reductive carboxylation. As a consequence, combined targeting of eIF4A and glutaminase activity more effectively inhibits PDA cell growth both in vitro and in vivo. Overall, our work demonstrates the importance of eIF4A in translational control of pancreatic tumour metabolism and as a therapeutic target against PDA.


Assuntos
Biossíntese de Proteínas , Animais , Carcinogênese , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Fator de Iniciação 4A em Eucariotos/antagonistas & inibidores , Fator de Iniciação 4A em Eucariotos/metabolismo , Glutationa/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Terapia de Alvo Molecular , Oxirredução , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas
5.
Nat Commun ; 10(1): 1424, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30926808

RESUMO

The drivers and the specification of CD4+ T cell differentiation in the tumor microenvironment and their contributions to tumor immunity or tolerance are incompletely understood. Using models of pancreatic ductal adenocarcinoma (PDA), we show that a distinct subset of tumor-infiltrating dendritic cells (DC) promotes PDA growth by directing a unique TH-program. Specifically, CD11b+CD103- DC predominate in PDA, express high IL-23 and TGF-ß, and induce FoxP3neg tumor-promoting IL-10+IL-17+IFNγ+ regulatory CD4+ T cells. The balance between this distinctive TH program and canonical FoxP3+ TREGS is unaffected by pattern recognition receptor ligation and is modulated by DC expression of retinoic acid. This TH-signature is mimicked in human PDA where it is associated with immune-tolerance and diminished patient survival. Our data suggest that CD11b+CD103- DC promote CD4+ T cell tolerance in PDA which may underscore its resistance to immunotherapy.


Assuntos
Células Dendríticas/imunologia , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Neoplasias Pancreáticas/imunologia , Linfócitos T Reguladores/imunologia , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Diferenciação Celular , Progressão da Doença , Fatores de Transcrição Forkhead , Regulação Neoplásica da Expressão Gênica , Humanos , Lectinas Tipo C/metabolismo , Camundongos Endogâmicos C57BL , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fenótipo , Transdução de Sinais , Células Th17/imunologia , Receptor 2 Toll-Like/metabolismo , Tretinoína/metabolismo , Neoplasias Pancreáticas
6.
Cancer Discov ; 8(4): 403-416, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29567829

RESUMO

We found that the cancerous pancreas harbors a markedly more abundant microbiome compared with normal pancreas in both mice and humans, and select bacteria are differentially increased in the tumorous pancreas compared with gut. Ablation of the microbiome protects against preinvasive and invasive pancreatic ductal adenocarcinoma (PDA), whereas transfer of bacteria from PDA-bearing hosts, but not controls, reverses tumor protection. Bacterial ablation was associated with immunogenic reprogramming of the PDA tumor microenvironment, including a reduction in myeloid-derived suppressor cells and an increase in M1 macrophage differentiation, promoting TH1 differentiation of CD4+ T cells and CD8+ T-cell activation. Bacterial ablation also enabled efficacy for checkpoint-targeted immunotherapy by upregulating PD-1 expression. Mechanistically, the PDA microbiome generated a tolerogenic immune program by differentially activating select Toll-like receptors in monocytic cells. These data suggest that endogenous microbiota promote the crippling immune-suppression characteristic of PDA and that the microbiome has potential as a therapeutic target in the modulation of disease progression.Significance: We found that a distinct and abundant microbiome drives suppressive monocytic cellular differentiation in pancreatic cancer via selective Toll-like receptor ligation leading to T-cell anergy. Targeting the microbiome protects against oncogenesis, reverses intratumoral immune tolerance, and enables efficacy for checkpoint-based immunotherapy. These data have implications for understanding immune suppression in pancreatic cancer and its reversal in the clinic. Cancer Discov; 8(4); 403-16. ©2018 AACR.See related commentary by Riquelme et al., p. 386This article is highlighted in the In This Issue feature, p. 371.


Assuntos
Carcinogênese , Microbiota , Monócitos/fisiologia , Neoplasias Pancreáticas/microbiologia , Receptores Toll-Like/metabolismo , Animais , Bactérias , Diferenciação Celular , Feminino , Humanos , Masculino , Camundongos , Monócitos/imunologia , Monócitos/metabolismo , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Transdução de Sinais
7.
Cancer Cell ; 34(5): 757-774.e7, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30423296

RESUMO

Pancreatic ductal adenocarcinoma (PDA) is characterized by immune tolerance and immunotherapeutic resistance. We discovered upregulation of receptor-interacting serine/threonine protein kinase 1 (RIP1) in tumor-associated macrophages (TAMs) in PDA. To study its role in oncogenic progression, we developed a selective small-molecule RIP1 inhibitor with high in vivo exposure. Targeting RIP1 reprogrammed TAMs toward an MHCIIhiTNFα+IFNγ+ immunogenic phenotype in a STAT1-dependent manner. RIP1 inhibition in TAMs resulted in cytotoxic T cell activation and T helper cell differentiation toward a mixed Th1/Th17 phenotype, leading to tumor immunity in mice and in organotypic models of human PDA. Targeting RIP1 synergized with PD1-and inducible co-stimulator-based immunotherapies. Tumor-promoting effects of RIP1 were independent of its co-association with RIP3. Collectively, our work describes RIP1 as a checkpoint kinase governing tumor immunity.


Assuntos
Carcinoma Ductal Pancreático/imunologia , Tolerância Imunológica/imunologia , Macrófagos/imunologia , Neoplasias Pancreáticas/imunologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Linfócitos T Citotóxicos/imunologia , Células Th1/imunologia , Células Th17/imunologia , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Humanos , Tolerância Imunológica/genética , Células L , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Fator de Transcrição STAT1/metabolismo , Células Th1/citologia , Células Th17/citologia
9.
Rev. salud bosque ; 5(2): 101-114, 2015.
Artigo em Espanhol | LILACS | ID: lil-779455

RESUMO

El presente trabajo se centra en el análisis de los elementos más relevantes, documentados mediante una revisión de la literatura científica relacionada con los principales aspectos de la formulación de una política pública para la regulación, planificación, gestión y evaluación de la tecnología biomédica y, más específicamente, para los dispositivos médicos de uso en el medio hospitalario. Esta revisión permite identificar algunos elementos clave, como son los aspectos de regulación, planificación sectorial, relacionamiento con la industria y evaluación económica de nuevas tecnologías, entre otros, que han sido de utilidad para la actualización y modernización de las políticas públicas en este campo y que, en conclusión, afectan de manera importante la sostenibilidad financiera de los sistemas, así como la valoración de la eficacia clínica de las intervenciones, la calidad de la atención y la seguridad del paciente. Estos aspectos, en su conjunto, deben ser considerados en el momento de formular una política pública para la regulación de este tipo de tecnologías biomédicas...


This paper focuses on the analysis of the most important elements, documented through review of literature related to the main specific aspects of the formulation of public policy for regulation, planning, management and evaluation of biomedical technology, and more specifically, medical devices for use in hospitals. This review identifies some key elements such as the regulatory, sectorial planning, relations with industry and economic evaluation of new technologies, among others, which have been useful for updating and modernizing public policies in this area and in conclusion significantly affect the financial sustainability of the systems and the evaluation of clinical efficacy of interventions, quality of care and patient safety. Aspects as a whole must be considered when formulating public policy to regulate this type of biomedical technologies...


Assuntos
Humanos , Efetividade , Equipamentos e Provisões , Gestão da Qualidade Total , Segurança , Tecnologia Biomédica
12.
Cochabamba; s.n; jun. 2012. 105 p. tab, graf.
Tese em Espanhol | LIBOCS, LILACS, LIBOE | ID: biblio-1296181

RESUMO

El envejecimiento es la continuación de un proceso de modificación biológica, psicológica y social que se estructura en función del tiempo, la vida del adulto mayor resulta dependiente no sólo del componente biológico del ser humano, sino de las condiciones del medio relacional en el que se encuentra.Cada ser humano atraviesa el proceso de envejecimiento de acuerdo al estilo de vida que adopta. Entre los factores de riesgo principales del deterioro de la calidad de vida, se halla el aislamiento social ligado a la exclusión y rechazo de la vejez. El presente estudio se realizó con el objetivo de conocer los problemas de salud y condiciones en las que llega el adulto mayor al hospital de la Caja Nacional de Salud.Serealizo desde un enfoque cuantitativo, prospectivo, transversal y descriptivo. Se utilizó la observación y la entrevista estructurada que contenía los indicadores necesarios para medir las variables del estudio. Los resultados obtenidos reflejan que el deterioro de la salud son:físicamente en un 38%, psicológicamente en un 45%y una relación social regular en un 49%, llevando todo esto a una mala calidad de vida del adulto mayor


Assuntos
Idoso , Idoso , Idoso Fragilizado , Bolívia , Qualidade de Vida , Saúde do Adulto , Serviços de Saúde para Idosos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA