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1.
Front Psychol ; 11: 631, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670123

RESUMO

Service providers personality traits is one of important determinants to deliver proper service to customers to make them satisfied in service delivery. Despite numerous studies on personality traits and emotional labor, little empirical work has been conducted to investigate the causal effects of hotel middle managers' personality traits on their commitment to the hospitality industry. Thus, this study aims to examine the effects of hotel middle managers' personality on two dimensions of commitments: organizational commitment and service quality commitment meditated by emotional variables: emotional labor and emotional exhaustion. The sample of this study consists of 266 department managers from full-service hotels in a metropolitan city in the Southern United States. The results confirmed the significant role of hotel middle managers' personality traits, especially expressive personality, in organizational commitment and service quality commitment. Hotel operators should foster a work setting that consistently promotes congruent emotions via regular training and screening to reducing employees' emotional exhaustion, increasing organizational commitment and service quality commitment, ultimately, reducing employees' turnover intentions.

2.
Cell ; 173(2): 515-528.e17, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29625057

RESUMO

Bladder cancer is the fifth most prevalent cancer in the U.S., yet is understudied, and few laboratory models exist that reflect the biology of the human disease. Here, we describe a biobank of patient-derived organoid lines that recapitulates the histopathological and molecular diversity of human bladder cancer. Organoid lines can be established efficiently from patient biopsies acquired before and after disease recurrence and are interconvertible with orthotopic xenografts. Notably, organoid lines often retain parental tumor heterogeneity and exhibit a spectrum of genomic changes that are consistent with tumor evolution in culture. Analyses of drug response using bladder tumor organoids show partial correlations with mutational profiles, as well as changes associated with treatment resistance, and specific responses can be validated using xenografts in vivo. Our studies indicate that patient-derived bladder tumor organoids represent a faithful model system for studying tumor evolution and treatment response in the context of precision cancer medicine.


Assuntos
Neoplasias da Bexiga Urinária/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Variações do Número de Cópias de DNA , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Mutação , Organoides/citologia , Organoides/efeitos dos fármacos , Organoides/metabolismo , Medicina de Precisão , Transplante Heterólogo , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/metabolismo
3.
Front Psychol ; 9: 2526, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30662415

RESUMO

Previous studies have used various external variables and parameters as well as moderator variables such as emotional intelligence have been to understand emotional labor and its related problems. However, a comprehensive model to study such variables' correlations with each other and their overall effect on emotional labor has not yet been established. This study used a structural equation model to understand the relationship between employees' expression of emotional labor and perception of customer feedbacks. The study also looked at how the perception of customer feedback affects emotional exhaustion in order to understand how emotional exhaustion affects job satisfaction and turnover intentions. Further, in order to fully understand the effects of emotion on emotional labor at the service contact points, this study developed and tested a model of emotional labor with four factors of emotional intelligence as moderating factors. Five hundred and seventy nine emotional labor workers in service industries in the United States were collected and 577 valid survey results have been analyzed. The result shows that there exists moderating effects of emotional intelligence on how employees' Deep Acting and Surface Acting recognize customers' reactions, both positive and negative, that would affect employees' Emotional Exhaustion and Job Satisfaction, and hence, Turnover Intention. The result suggests that employees with better understanding of their own emotions, although they are more likely to recover from emotional exhaustion, experience a greater negative effect when there is a discrepancy between what they feel and how they should act.

4.
Curr Opin Cell Biol ; 37: 35-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26506127

RESUMO

Analyses of cell types of origin for prostate cancer should result in new insights into mechanisms of tumor initiation, and may lead to improved prognosis and selection of appropriate therapies. Here, we review studies using a range of methodologies to investigate the cell of origin for mouse and human prostate cancer. Notably, analyses using tissue recombination assays support basal epithelial cells as a cell of origin, whereas in vivo lineage-tracing studies in genetically-engineered mice implicate luminal cells. We describe how these results can be potentially reconciled by a conceptual distinction between cells of origin and cells of mutation, and outline how new experimental approaches can address the potential relationship between cell types of origin and disease outcome.


Assuntos
Neoplasias da Próstata , Animais , Transformação Celular Neoplásica/metabolismo , Células Epiteliais/metabolismo , Humanos , Masculino , Mutação , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Microambiente Tumoral
5.
Stem Cells ; 33(11): 3356-67, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26220362

RESUMO

The precise role of Wnt/ß-catenin signaling during prostatic development and tumorigenesis is unclear. Axin2 is a direct transcriptional target of ß-catenin. Recent studies have shown that Axin2-expressing cells have stem/progenitor cell properties in a variety of mouse tissues. Here, we genetically labeled Axin2-expressing cells at various time points and tracked their cellular behavior at different developmental and mature stages. We found that prostatic Axin2-expressing cells mainly express luminal epithelial cell markers and are able to expand luminal cell lineages during prostatic development and maturation. They can also survive androgen withdrawal and regenerate prostatic luminal epithelial cells following androgen replacement. Deletion of ß-catenin or expression of stabilized ß-catenin in these Axin2-expressing cells results in abnormal development or oncogenic transformation, respectively. Our study uncovers a critical role of Wnt/ß-catenin-responsive cells in prostatic development and regeneration, and that dysregulation of Wnt/ß-catenin signaling in these cells contributes to prostatic developmental defects and tumorigenesis.


Assuntos
Proteína Axina/biossíntese , Próstata/crescimento & desenvolvimento , Próstata/metabolismo , Regeneração/fisiologia , Via de Sinalização Wnt/fisiologia , beta Catenina/biossíntese , Animais , Linhagem da Célula , Células Epiteliais/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Organogênese/fisiologia , Próstata/citologia
6.
J Biol Chem ; 290(5): 2759-68, 2015 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25527506

RESUMO

Both androgen action and PI3K medicated signaling pathways have been implicated in prostate tumorigenesis. Our androgen receptor (AR) conditional transgenic mice developed murine prostatic intraepithelial neoplasia (mPIN) and prostatic adenocarcinoma lesions recapitulating human prostate cancer development and progression. Role of transgenic AR contributing to malignancy was demonstrated by high degree of transgenic AR expression in atypical and tumor cells in mPIN as well as prostatic adenocarcinoma lesions of the transgenic mice, but not in adjacent normal tissue. Interestingly, reduced PI3K/Akt activation also appeared in these mouse atypical and tumor cells, suggesting an interaction between androgen and PI3K/AKT pathways. In this study, we further investigated this interaction. We showed that the androgen depletion or knockdown of AR expression results in elevated levels of active phosphorylated AKT in prostate cancer cells. Castration of conditional Pten knock-out mice showed increased Akt, phosphorylated Akt, and pS6 expression in the mouse prostate. Using a series of newly generated Ar reporter and Pten knock-out compound mice, we showed that Pten loss directly represses endogenous Ar expression in prostatic epithelial cells. Moreover, Pten loss and PI3K/Akt activation reduced Ar-mediated transcription in purified Pten-null cells. This study provides novel evidence demonstrating interplay between androgen and PI3K pathways, as well as introduces unique and relevant mouse models for further studies of PI3K and AR pathways in the context of prostate tumorigenesis.


Assuntos
Fosfatidilinositol 3-Quinases/metabolismo , Próstata/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Androgênios/metabolismo , Animais , Western Blotting , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Knockout , Neoplasias da Próstata/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/fisiologia
7.
J Biol Chem ; 288(50): 35913-24, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24174533

RESUMO

ZMIZ2, also named ZIMP7, is a protein inhibitor of activated STAT (PIAS)-like protein and a transcriptional coactivator. In this study, we investigated the interaction between ZMIZ2 and ß-catenin, a key regulator of the Wnt signaling pathway. We demonstrated that the expression of exogenous ZMIZ2 augments TCF (T cell factor) and ß-catenin-mediated transcription. In contrast, shRNA knockdown of ZMIZ2 expression specifically represses the enhancement of TCF/ß-catenin-mediated transcription by ZMIZ2. Using Wnt3a-conditioned medium, we demonstrated that ZMIZ2 can enhance Wnt ligand-induced TCF/ß-catenin-mediated transcription. We also showed a promotional role of ZMIZ2 in enhancing ß-catenin downstream target gene expression in human cells and in Zmiz2 null (Zmiz2(-/-)) mouse embryonic fibroblasts (MEFs). The regulatory role of Zmiz2 in Wnt-induced TCF/ß-catenin-mediated transcription can be restored in Zmiz2(-/-) MEFs that were infected with adenoviral expression vectors for Zmiz2. Moreover, enhancement of Zmiz2 on TCF/ß-catenin-mediated transcription was further demonstrated in Zmiz2 knockout and Axin2 reporter compound mice. Furthermore, the protein-protein interaction between ZMIZ2 and ß-catenin was identified by co-immunoprecipitation and in vitro protein pulldown assays. We also observed recruitment of endogenous ZMIZ2 onto the promoter region of the Axin 2 gene, a ß-catenin downstream target promoter, in a Wnt ligand-inducible manner. Finally, a promotional role of ZMIZ2 on cell growth was demonstrated in human cell lines and Zmiz2 knockout MEFs. Our findings demonstrate a novel interaction between ZMIZ2 and ß-catenin and elucidate a novel mechanism for PIAS-like proteins in regulating Wnt signaling pathways.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Transdução de Sinais , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Proteína Axina/genética , Linhagem Celular , Proliferação de Células , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Receptores de Hialuronatos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Regiões Promotoras Genéticas/genética , Proteínas Inibidoras de STAT Ativados , Fatores de Transcrição TCF/metabolismo , Transcrição Gênica
8.
J Biol Chem ; 288(6): 3727-38, 2013 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-23275340

RESUMO

Using an Lzts2 knock-out mouse model, we characterized the biological role of Lzts2 in tumorigenesis. Both heterozygous and homozygous deletion of the Lzts2-targeted allele in mice shows an increased incidence in spontaneous tumor development, although Lzts2 homozygous knock-out mice show significantly higher incidences than heterozygous mice. Treatment of Lzts2-deficient mice with a carcinogen, N-butyl-N-(4-hydroxybutyl) nitrosamine, increases the susceptibility to N-butyl-N-(4-hydroxybutyl) nitrosamine-induced bladder carcinoma development. Examination of human prostate cancer tissue specimens shows a reduction of LZTS2 protein expression in prostate cancer cells. Further analyses of mouse embryonic fibroblasts isolated from Lzts2 knock-out embryos show that loss of Lzts2 enhances cell growth. These data provide the first line of evidence demonstrating that deletion of Lzts2 increases susceptibility to spontaneous and carcinogen-induced tumor development.


Assuntos
Proteínas de Ciclo Celular/biossíntese , Proteínas de Ligação a DNA/biossíntese , Deleção de Genes , Predisposição Genética para Doença , Neoplasias da Próstata/metabolismo , Proteínas Supressoras de Tumor/biossíntese , Neoplasias da Bexiga Urinária/metabolismo , Animais , Butilidroxibutilnitrosamina/toxicidade , Carcinógenos/toxicidade , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Heterozigoto , Humanos , Masculino , Camundongos , Camundongos Knockout , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Supressoras de Tumor/genética , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
9.
PLoS One ; 8(1): e53476, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23308230

RESUMO

The PTEN tumor suppressor gene is frequently inactivated in human prostate cancer. Using Osr1 (odd skipped related 1)-Cre mice, we generated a novel conditional Pten knockout mouse strain, Pten(LoxP):Osr1-Cre. Conditional biallelic and monoallelic Pten knockout mice were viable. Deletion of Pten expression was detected in the prostate of Pten(LoxP/LoxP):Osr1-Cre mice as early as 2 weeks of age. Intriguingly, Pten(LoxP/LoxP):Osr1-Cre mice develop high-grade prostatic intraepithelial neoplasms (PINs) with high penetrance as early as one-month of age, and locally invasive prostatic tumors after 12-months of age. Pten(LoxP/+):Osr1-Cre mice show only mild oncogenic changes after 8-weeks of age. Castration of Pten(LoxP/LoxP):Osr1-Cre mice shows no significant regression of prostate tumors, although a shift of androgen receptor (AR) staining from the nuclei to cytoplasm is observed in Pten null tumor cells of castrated mice. Enhanced Akt activity is observed in Pten null tumor cells of castrated Pten(LoxP/LoxP):Osr1-Cre. This study provides a novel mouse model that can be used to investigate a primary role of Pten in initiating oncogenic transformation in the prostate and to examine other genetic and epigenetic changes that are required for tumor progression in the mouse prostate.


Assuntos
Deleção de Genes , Camundongos Transgênicos , PTEN Fosfo-Hidrolase/genética , Próstata/patologia , Neoplasia Prostática Intraepitelial/genética , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Idade de Início , Alelos , Animais , Castração , Transformação Celular Neoplásica , Progressão da Doença , Efeito Fundador , Expressão Gênica , Integrases/genética , Integrases/metabolismo , Masculino , Camundongos , Invasividade Neoplásica , PTEN Fosfo-Hidrolase/deficiência , Próstata/metabolismo , Neoplasia Prostática Intraepitelial/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
10.
Cell Immunol ; 280(1): 1-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23246829

RESUMO

Vitamin-D3 upregulated protein-1 (VDUP1) is a stress response protein. Pseudomonas aeruginosa (P. aeruginosa) infection is a leading cause of death. Mice infected with live P. aeruginosa exhibit significantly decreased VDUP1 expression. However, the function of VDUP1 during P. aeruginosa-induced mouse bacteremic shock is unknown. To address the function of VDUP1 in P. aeruginosa-infected mice, we constructed a bacteremic shock model wherein both wild-type and VDUP1-deficient mice were infected intra-peritoneally with live P. aeruginosa. We found that VDUP1-deficient mice were more resistant to P. aeruginosa-induced bacteremic shock than wild-type mice, as shown by the increased survival, accelerated bacterial clearance and suppression of cytokine overproduction of the VDUP1-deficient mice. VDUP1 promoted the recruitment of neutrophils into the peritoneal cavities of infected mice. VDUP1 impeded the phagocytosis of non-opsonized P. aeruginosa via phosphatidylinositide 3-kinase (PI3K) pathway in macrophages. P. aeruginosa infection induced the generation of reactive oxygen species (ROS), and the increased production of ROS by the peritoneal cells of VDUP1-deficient mice was advantageous in clearing the bacteria. Overall, VDUP1 aggravates bacteremic shock; thus, VDUP1 can be considered a target molecule for the inhibition of P. aeruginosa-induced bacteremic shock.


Assuntos
Proteínas de Transporte/fisiologia , Peritonite/fisiopatologia , Infecções por Pseudomonas/fisiopatologia , Choque Séptico/fisiopatologia , Tiorredoxinas/fisiologia , Animais , Apoptose/fisiologia , Proteínas de Transporte/genética , Quimiotaxia de Leucócito/fisiologia , Contagem de Colônia Microbiana , Citocinas/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/patologia , Cavidade Peritoneal/microbiologia , Cavidade Peritoneal/patologia , Peritonite/microbiologia , Fagocitose/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Organismos Livres de Patógenos Específicos , Baço/microbiologia , Tiorredoxinas/genética
11.
Blood ; 118(20): 5476-86, 2011 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-21960590

RESUMO

Perforin (Prf1) and granzyme B (GzmB) are essential effector molecules for natural killer (NK)-cell cytotoxicity, but how Prf1 and GzmB expression is regulated during arming of NK cells is poorly defined. We show that human microRNA (miR)-27a* is a negative regulator of NK-cell cytotoxicity by silencing Prf1 and GzmB expression. Human miR-27a* specifically bound to the 3' untranslated regions of Prf1 and GzmB, down-regulating expression in both resting and activated NK cells, and it functioned as a fine-tuner for homeostasis of the net amount of the effector proteins. Consistent with miR-27a* having an inhibitory role, knockdown of miR-27a* in NK cells dramatically increased cytotoxicity in vitro and decreased tumor growth in a human tumor xenograft model. Thus, NK-cell cytotoxicity is regulated, in part, by microRNA, and modulating endogenous miR-27a* levels in NK cells represents a potential immunotherapeutic strategy.


Assuntos
Neoplasias do Colo/imunologia , Granzimas/genética , Células Matadoras Naturais/fisiologia , MicroRNAs/fisiologia , Proteínas Citotóxicas Formadoras de Poros/genética , Regiões 3' não Traduzidas/genética , Animais , Linhagem Celular Transformada , Linhagem Celular Tumoral , Células Cultivadas , Neoplasias do Colo/terapia , Feminino , Sangue Fetal/citologia , Inativação Gênica , Terapia Genética/métodos , Humanos , Células Matadoras Naturais/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , MicroRNAs/farmacologia , Perforina , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Immunol Lett ; 141(1): 61-7, 2011 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-21835206

RESUMO

The IL-22 NKp46(+) innate lymphoid cells, NCR22 cells, are very important for the early host defense against microbial pathogens. We show here that NCR22 cells were differentiated from Lin(-)CD127(+)CD117(+) cells that were derived from hematopoietic precursor cells (HPCs) of mouse bone marrow cells. The combination of low concentrations of IL-23 and IL-15 induced differentiation of NCR22 cells from Lin(-)CD127(+)CD117(+) cells. NCR22 cells expressed a large amount of IL-22 and RORγt, and they had poor cytolytic activity and produced little IFN-γ. Lin(-)CD127(+)CD117(+) cells were very similar to intestinal lamina propria LTi-like cells; both cells dominantly expressed RORγt and IL-22. Meanwhile, Lin(-)CD127(-)CD117(+) cells that were also derived from HPCs did not express RORγt and IL-22, and they developed into conventional NK cells, not into NCR22 cells. These findings revealed that NCR22 cells can be differentiated from Lin(-)CD127(+)CD117(+) cells which are derived from HPCs.


Assuntos
Antígenos Ly/metabolismo , Diferenciação Celular/fisiologia , Interleucinas/biossíntese , Células Matadoras Naturais , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/biossíntese , Animais , Feminino , Células-Tronco Hematopoéticas/metabolismo , Interleucina-15/imunologia , Interleucina-15/metabolismo , Interleucina-23/metabolismo , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Mucosa Intestinal/metabolismo , Células Matadoras Naturais/citologia , Células Matadoras Naturais/metabolismo , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-kit/metabolismo , Interleucina 22
13.
Mol Cells ; 32(3): 265-72, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21809216

RESUMO

Interleukin 10 (IL-10) is a multifunctional cytokine that regulates diverse functions of immune cells. Natural killer (NK) cells express the IL-10 and IL-10 receptor, but little is known about the function of IL-10 on NK cell activation. In this study, we show the expression and role of IL-10 in human NK cells. Among the cytokines tested, IL-15 was the most potent inducer of IL-10, with a maximal peak expression at 5 h after treatment. Furthermore, IL-10 receptor was shown to be expressed in NK cells. IL-10 alone had a significant effect on NK cytotoxicity which additively increased NK cell cytotoxicity in the presence of IL-15. Neutralizing IL-10 with anti-IL-10 antibody suppressed the inductive effect of IL-10 on NK cell cytotoxicity; however, IL-10 had no effect on IFN-γ or TNF-α production or NK cell activatory receptor expression. STAT signals are implicated as a key mediator of IL-10/IL-15 cytotoxicity response. Thus, the effect of IL-10 on NK cells is particularly interesting with regard to the STAT3 signal that was enhanced by IL-10 or IL-15.


Assuntos
Citotoxicidade Imunológica/efeitos dos fármacos , Interleucina-10 , Interleucina-15/imunologia , Células Matadoras Naturais/imunologia , Receptores de Interleucina-10/imunologia , Transdução de Sinais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Interferon gama/imunologia , Interleucina-10/antagonistas & inibidores , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-15/metabolismo , Interleucina-15/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Receptores de Interleucina-10/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fator de Necrose Tumoral alfa/imunologia
14.
Immunol Lett ; 137(1-2): 70-7, 2011 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-21354208

RESUMO

Natural killer (NK) cells are differentiated from hematopoietic stem cells (HSCs) which are located at the lowest end of an oxygen gradient within the bone marrow (BM). In this report, we investigated whether oxygen tension could affect NK cell differentiation from hematopoietic cells in vitro. We found that hypoxia led to an inhibition of differentiation in NK cells, and increased oxygen supply alleviated this inhibition and restored NK cell differentiation under hypoxic condition. Hypoxia-treated cells demonstrated reduced mRNA expression of transcription factors (TFs) that have important roles in NK cell differentiation, such as EOMES, T-bet, GATA-3 and ETS-1. Moreover, hypoxia-pretreated cells recovered mRNA expression of TFs when the oxygen tension was changed to normoxia. Our findings suggest that oxygen tension modulates in vitro differentiation of NK cells through the regulation of TF expression.


Assuntos
Fator de Transcrição GATA3/metabolismo , Células Matadoras Naturais/efeitos dos fármacos , Oxigênio/administração & dosagem , Proteína Proto-Oncogênica c-ets-1/metabolismo , Proteínas com Domínio T/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Fator de Transcrição GATA3/genética , Células-Tronco Hematopoéticas/fisiologia , Humanos , Hipóxia/genética , Hipóxia/patologia , Hipóxia/prevenção & controle , Células Matadoras Naturais/patologia , Células Matadoras Naturais/fisiologia , Oxigênio/metabolismo , Proteína Proto-Oncogênica c-ets-1/genética , Proteínas com Domínio T/genética
15.
Lung Cancer ; 74(2): 293-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21440951

RESUMO

PURPOSE: It has been suggested that hepatocyte growth factor (HGF) and insulin-like growth factor binding protein (IGFBP)-3 are associated with gefitinib resistance in non-small cell lung cancer (NSCLC). We investigated the predictive and prognostic roles of these proteins in NSCLC patients treated with gefitinib. PATIENTS AND METHODS: Of 106 patients enrolled in a randomized phase II study of gefitinib, 97 had plasma samples available for ELISA testing. Of these samples, seven and eight, respectively, had HGF and IGFBP-3 values that could not be measured. Therefore, the correlations between clinical outcomes and plasma levels of HGF and IGFBP-3 were evaluated in 90 and 89 patients, respectively. RESULTS: Plasma HGF levels were significantly higher in older patients, male patients, patients with squamous cell carcinoma, current smokers, and patients with epidermal growth factor receptor (EGFR) wild-type tumors. Low HGF levels were significantly associated with higher response rate, and longer progression-free survival (PFS) and overall survival (OS) irrespective of EGFR mutation status. In a multivariate analysis, the presence of EGFR mutations (P=0.002) and low HGF levels (P=0.031) were independently predictive of longer PFS, and an ECOG PS of 0 (P=0.001) and low HGF levels (P=0.002) were independently predictive of longer OS. No statistically significant differences were found for IGFBP-3. CONCLUSION: High HGF levels are significantly associated with resistance to gefitinib and can be used as a predictive marker for the differential outcome of gefitinib treatment in NSCLC irrespective of EGFR mutation status.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Quinazolinas/administração & dosagem , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Farmacológicos/sangue , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Análise Mutacional de DNA , Resistência a Medicamentos , Feminino , Gefitinibe , Genes erbB-1/genética , Fator de Crescimento de Hepatócito/sangue , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mutação/genética , Valor Preditivo dos Testes , Prognóstico , Quinazolinas/efeitos adversos , Fatores de Risco , Fatores Sexuais , Fumar , Análise de Sobrevida , Resultado do Tratamento
16.
Immunol Lett ; 136(1): 29-36, 2011 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-21126536

RESUMO

Natural killer (NK) cells act important roles in innate immunity and adaptive immunity. However, the mechanisms governing NK cell development have not been clearly elucidated. Previous studies have shown that an HMG (high-mobility group) protein, TOX, is important for regulating the differentiation program of developing T cells in mice. In this study, we examined the role of TOX in differentiation of human NK cells. Knockdown of TOX in differentiating cells decreased the NK cell population identified by expression of NK surface markers and receptors. In addition, over-expression of TOX enhanced the differentiation of NK cells which give rise to a population showing effector functions of mature NK cells. Moreover, TOX influenced expression of T-bet (T-box expressed in T cells, also as known as Tbx21) during NK cell development. Overall, these results suggest that TOX is required for IL-15-mediated NK cell differentiation and affected expression of T-bet that plays critical roles in NK differentiation and maturation.


Assuntos
Diferenciação Celular , Células-Tronco Hematopoéticas/imunologia , Proteínas de Grupo de Alta Mobilidade/imunologia , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/citologia , Proteínas de Grupo de Alta Mobilidade/genética , Humanos , Células K562 , RNA Interferente Pequeno/genética , Transcrição Gênica
17.
J Immunol ; 185(2): 917-28, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20543098

RESUMO

NK cells are capable of killing virus-infected or tumor cells and producing IFN-gamma. Resting NK cells, however, have only minimal cytolytic activity and secrete a low level of IFN-gamma. The cytokine IL-15 can promote the expression of effector functions by resting NK cells. In this study, we demonstrate that suppressor of cytokine signaling 2 (SOCS2) has a novel role in IL-15-primed human NK cell function. SOCS2 expression was upregulated in NK cells following stimulation with IL-15. During IL-15-mediated NK cell priming, SOCS2 interacted with phosphorylated proline-rich tyrosine kinase 2 (Pyk2) at tyrosine 402 (p-Pyk2(Tyr402)) and induced the proteasome-mediated degradation of p-Pyk2(Tyr402) via ubiquitination. Knockdown of SOCS2 resulted in the accumulation of p-Pyk2(Tyr402) and blocked NK cell effector functions. In addition, NK cell cytolytic activity and IFN-gamma production were inhibited by overexpression of the wild-type of Pyk2 but not by the overexpression of tyrosine 402 mutant of Pyk2. These results suggest that SOCS2 regulates human NK cell effector functions via control of phosphorylated Pyk2 depending on IL-15 existence.


Assuntos
Quinase 2 de Adesão Focal/metabolismo , Interleucina-15/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Citotoxicidade Imunológica/imunologia , Quinase 2 de Adesão Focal/genética , Humanos , Recém-Nascido , Interferon gama/metabolismo , Células Jurkat , Células K562 , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Mutação , Fosforilação/efeitos dos fármacos , Ligação Proteica , Interferência de RNA , Receptores de Interleucina-15/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Proteínas Supressoras da Sinalização de Citocina/genética , Tirosina/metabolismo
18.
Immunol Lett ; 129(2): 78-84, 2010 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-20156484

RESUMO

The detailed mechanism driving the germinal center (GC) reaction to B cell lymphomagenesis has not been clarified. Thioredoxin interacting protein (TXNIP), also known as vitamin D3 up-regulated protein 1 which is an important tumor repressor, is involved in stress responses, redox regulation, and cellular proliferation. Here, we report that TXNIP has a potential role in the formation of GC in peripheral lymphoid organs where B lymphocytes divide rapidly. First, we compared changes in GC from wild type mice and Txnip(-/-) mice. After immunization, Txnip(-/-) mice exhibited higher expression level of BCL-6 and larger percentage of GC B cells with the reduction in antibody production and plasma cell numbers. In addition, Txnip(-/-) spleens had a much larger population which expressed Ki-67, a marker of cell proliferation, in the red pulp border than WT spleens. Furthermore, the expression of BCL-6 was decreased in TXNIP overexpressing cells and elevated in TXNIP deficient cells. Taken together, we conclude that TXNIP may contribute to the formation of GCs after immunization. During this process, TXNIP suppresses BCL-6 expression.


Assuntos
Linfócitos B/imunologia , Proteínas de Transporte/imunologia , Regulação para Baixo , Centro Germinativo/citologia , Centro Germinativo/imunologia , Proteínas Proto-Oncogênicas c-bcl-6/imunologia , Animais , Sequência de Bases , Western Blotting , Proliferação de Células , Citometria de Fluxo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Plasmídeos/genética , Proteínas Proto-Oncogênicas c-bcl-6/genética
19.
Int Immunopharmacol ; 10(4): 481-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20116458

RESUMO

NK cells play crucial roles in innate immunity and adaptive immunity. The detailed mechanisms, however, governing NK cell development remains unclear. In this study, we report that YC-1 significantly enhances NK cell populations differentiated from human umbilical cord blood hematopoietic stem cells (HSCs). NK cells increased by YC-1 display both phenotypic and functional features of fully mature NK (mNK) cells, but YC-1 does not affect the activation of mNK cells. YC-1 did not affect cGMP production and phosphorylation of STAT-5 which is essential for IL-15R signaling. On the other hand, YC-1 increased p38 MAPK phosphorylation during NK cell differentiation. Furthermore, p38 inhibitor SB203580 inhibited the differentiation of NK cells enhanced by YC-1. Taken together, these data suggest that YC-1 enhances NK cell differentiation through the activation of p38 MAPK which is involved in NK cell differentiation.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Ativadores de Enzimas/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Indazóis/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , GMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Sangue Fetal/citologia , Citometria de Fluxo , Humanos , Imidazóis/farmacologia , Indazóis/antagonistas & inibidores , Fosforilação , Piridinas/farmacologia , Receptores de Interleucina-15/efeitos dos fármacos , Fator de Transcrição STAT5/biossíntese , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
J Immunol ; 183(12): 7931-8, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19933860

RESUMO

Cross-linking of NK activating receptors activates phospholipase-gamma and subsequently induces diacylglycerol and Ca(2+) as second messengers of signal transduction. Previous studies reported that Ras guanyl nucleotide-releasing protein (RasGRP) 1, which is activated by diacylglycerol and Ca(2+), is crucial for TCR-mediated Ras-ERK activation. We now report that RasGRP1, which can also be detected in human NK cells, plays an essential role in NK cell effector functions. To examine the role of RasGRP1 in NK cell functions, the expression of RasGRP1 was suppressed using RNA interference. Knockdown of RasGRP1 significantly blocked ITAM-dependent cytokine production as well as NK cytotoxicity. Biochemically, RasGRP1-knockdown NK cells showed markedly decreased ability to activate Ras, ERK, and JNK. Activation of the Ras-MAPK pathway was independently shown to be indispensable for NK cell effector functions via the use of specific pharmacological inhibitors. Our results reveal that RasGRP1 is required for the activation of the Ras-MAPK pathway leading to NK cell effector functions. Moreover, our data suggest that RasGRP1 might act as an important bridge between phospholipase-gamma activation and NK cell effector functions via the Ras-MAPK pathway.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Sangue Fetal/citologia , Sangue Fetal/imunologia , Sangue Fetal/metabolismo , Fatores de Troca do Nucleotídeo Guanina/deficiência , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Líquido Intracelular/imunologia , Líquido Intracelular/metabolismo , Células K562 , Células Matadoras Naturais/patologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Cordão Umbilical/irrigação sanguínea , Cordão Umbilical/citologia , Cordão Umbilical/imunologia
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