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1.
Cardiology ; 148(2): 161-172, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36958302

RESUMO

INTRODUCTION: Pulmonary hypertension due to left heart failure (PH-LHF) is a disease with high prevalence and 3-year mortality rates. Consequently, timely identification of patients with high mortality risk is critical. This study aimed to build a nomogram for predicting 3-year mortality and screening high-risk PH-LHF patients. METHODS: This nomogram was developed on a training cohort of 175 patients with PH-LHF diagnosed by right heart catheterization. Multivariate Cox regression was used to identify independent predictors and develop this nomogram. The median total points obtained from the nomogram were used as a cutoff point, and patients were classified into low- and high-risk groups. The concordance index (C-index) and calibration curve were utilized to ascertain the predictive accuracy and discriminative ability of the nomogram. External validation was performed using a validation cohort of 77 PH-LHF patients from other centers. RESULTS: Multivariate Cox regression showed that the New York Heart Association Functional classification (NYHA FC), uric acid level, and mean pulmonary arterial pressure were all independent predictors and incorporated into the nomogram. The nomogram showed good discrimination (C-index of 0.756; 95% CI: 0.688-0.854) and good calibration. The Kaplan-Meier survival analysis showed that patients in the high-risk group had worse survival (p < 0.001). In the external validation, the nomogram showed both good discrimination (C-index of 0.738; 95% CI: 0.591-0.846) and calibration. CONCLUSION: The nomogram had a good performance in predicting 3-year mortality and can effectively identify high-risk patients. The nomogram may help to reduce the mortality of PH-LHF.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Humanos , Nomogramas , Estudos Retrospectivos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Sistema de Registros
2.
Chin Med J (Engl) ; 135(15): 1837-1845, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-36195993

RESUMO

BACKGROUND: Coronary artery disease (CAD) is the commonest cause of heart failure (HF), whereas pulmonary hypertension (PH) has not been established or reported in this patient population. Therefore, we assessed the prevalence, risk factors, and survival in CAD-associated HF (CAD-HF) complicated with PH. METHODS: Symptomatic CAD-HF patients were continuously enrolled in this prospective, multicenter registry study. Echocardiography, coronary arteriography, left and right heart catheterization (RHC), and other baseline clinical data were recorded. Patients were followed up and their survival was recorded. RESULTS: One hundred and eighty-two CAD-HF patients were enrolled, including 142 with HF with a preserved ejection fraction (heart failure with preserved ejection fraction [HFpEF]; left ventricular ejection fraction [LVEF] ≥50%) and 40 with a reduced ejection fraction (heart failure with reduced ejection fraction [HFrEF]; LVEF < 50%). PH was diagnosed with RHC in 77.5% of patients. Patients with PH showed worse hemodynamic parameters and higher mortality. HFrEF-PH patients had worse survival than HFpEF-PH patients. CAD-HF patients with an enlarged left ventricular end-diastolic diameter and reduced hemoglobin were at higher risk of PH. Nitrate treatment reduced the risk of PH. Elevated creatinine and mean pulmonary arterial pressure (mPAP), diastolic pressure gradient (DPG) ≥7 mmHg, and previous myocardial infarction (MI) entailed a higher risk of mortality in CAD-HF patients with PH. CONCLUSIONS: PH is common in CAD-HF and worsens the hemodynamics and survival in these patients. Left ventricle enlargement and anemia increase the risk of PH in CAD-HF. Patients may benefit from nitrate medications. Renal impairment, elevated mPAP, DPG ≥7 mmHg, and previous MI are strong predictors of mortality in CAD-HF-PH patients. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02164526.


Assuntos
Doença da Artéria Coronariana , Insuficiência Cardíaca , Hipertensão Pulmonar , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/epidemiologia , Creatinina , Insuficiência Cardíaca/complicações , Humanos , Hipertensão Pulmonar/complicações , Nitratos , Prevalência , Prognóstico , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Volume Sistólico , Função Ventricular Esquerda
3.
Front Cardiovasc Med ; 9: 908215, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35983183

RESUMO

Background: Pulmonary hypertension due to left heart failure (PH-LHF) is currently the most common form of pulmonary hypertension (PH) encountered in clinical practice. Despite significant advances that have improved our understanding of PH-LHF over the past two decades, the mortality is still high in recent decades. This study aimed to describe the prevalence and survival of patients with PH-LHF, and explored the potential risk factors which may predict the prognosis of PH-LHF. Methods: A retrospective analysis of a prospective cohort study of left heart failure (LHF) patients who underwent right heart catheterization (RHC) between January 2013 and November 2016 was performed. The endpoint was all-cause mortality. Follow-ups were performed every 6 months ± 2 weeks. Results: A total of 480 patients with LHF were enrolled, with 215 (44.8%) having PH-LHF. The proportion of PH-LHF was significantly lower in coronary artery disease (CAD) group than without CAD (41.3 vs. 57.8%, p = 0.003). However, multivariable logistic regression analysis revealed that CAD was not associated with PH-LHF (Adjusted OR: 1.055, 95% CI: 0.576 - 1.935, p = 0.862). 75 of 215 (34.9%) patients with PH-LHF died during a median follow-up period of 84.6 months. The 1-, 3-, 5-, and 8-year survival rates of all PH-LHF patients were 94.3, 76.9, 65.8, and 60.2%, respectively. New York Heart Association Functional Class (NYHA FC), hemoglobin, and systolic pulmonary artery pressure (sPAP) were associated with mortality of PH-LHF in multivariate Cox analysis. Conclusion: PH is commonly identified in patients with LHF, with a prevalence of approximately 45%. The mortality is still high in patients with PH-LHF. NYHA FC, hemoglobin, and sPAP are independent risk predictors of mortality for PH-LHF. These findings may be useful for risk stratification in future clinical trial enrollment.

4.
Front Cardiovasc Med ; 9: 983803, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035936

RESUMO

Background: Patients with left heart failure (LHF) are often associated with the development of pulmonary hypertension (PH) which leads to an increased risk of death. Recently, the diagnostic standard for PH has changed from mean pulmonary arterial pressure (mPAP) ≥25 mmHg to >20 mmHg. Nonetheless, the effect of borderline PH (mPAP: 21-24 mmHg) on the prognosis of LHF patients is unclear. This study aimed to investigate the relationship between borderline PH and 3-year clinical outcomes in LHF patients. Methods: A retrospective analysis of a prospective cohort study was done for LHF patients who underwent right heart catheterization (RHC) between January 2013 and November 2016. The primary outcome was all-cause mortality; the secondary outcome was rehospitalization. Results: Among 344 patients, 62.5% were identified with a proportion of PH (mPAP ≥ 25), 10.8% with borderline PH (21-24), and 26.7% with non-PH (≤20), respectively. Multivariable Cox analysis revealed that borderline PH patients had a higher adjusted mortality risk (HR = 3.822; 95% CI: 1.043-13.999; p = 0.043) than non-PH patients. When mPAP was treated as a continuous variable, the hazard ratio for death increased progressively with increasing mPAP starting at 20 mmHg (HR = 1.006; 95% CI: 1.001-1.012). There was no statistically significant difference in adjusted rehospitalization between borderline PH and non-PH patients (HR = 1.599; 95% CI: 0.833-3.067; p = 0.158). Conclusions: Borderline PH is independently related to increased 3-year mortality in LHF patients. Future research is needed to evaluate whether more close monitoring, and managing with an intensifier improves clinical outcomes in borderline PH caused by LHF. Clinical trials registration: www.clinicaltrials.gov NCT02164526.

5.
BMC Cardiovasc Disord ; 22(1): 56, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35172722

RESUMO

BACKGROUND: There is no generally accepted comprehensive risk prediction model cooperating risk factors associated with heart failure and pulmonary hemodynamics for patients with pulmonary hypertension due to left heart disease (PH-LHD). We aimed to explore outcome correlates and evaluate incremental prognostic value of pulmonary hemodynamics for risk prediction in PH-LHD. METHODS: Consecutive patients with chronic heart failure undergoing right heart catheterization were prospectively enrolled. The primary endpoint was all-cause mortality. Individual variable selection was performed by machine learning methods. Cox proportional hazards models were conducted to identify the association between variables and mortality. Incremental value of hemodynamics was evaluated based on the Seattle heart failure model (SHFM) and Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) scores. RESULTS: A total of 276 PH-LHD patients were enrolled, with a median follow-up time of 34.7 months. By L1-penalized regression model and random forest approach, diastolic pressure gradient (DPG) and mixed venous oxygen saturation (SvO2) were the hemodynamic predictors most strongly associated with mortality (coefficient: 0.0255 and -0.0176, respectively), with consistent significance after adjusted for SHFM [DPG: HR 1.067, 95% CI 1.024-1.113, P = 0.022; SvO2: HR 0.969, 95% CI 0.953-0.985, P = 0.002] or MAGGIC (DPG: HR 1.069, 95% CI 1.026-1.114, P = 0.011; SvO2: HR 0.970, 95% CI 0.954-0.986, P = 0.004) scores. The inclusion of DPG and SvO2 improved risk prediction compared with using SHFM [net classification improvement (NRI): 0.468 (0.161-0.752); integrated discriminatory index (IDI): 0.092 (0.035-0.171); likelihood ratio test: P < 0.001] or MAGGIC [NRI: 0.298 (0.106-0.615); IDI: 0.084 (0.033-0.151); likelihood ratio: P < 0.001] scores alone. CONCLUSION: In PH-LHD, pulmonary hemodynamics can provide incremental prognostic value for risk prediction. CLINICAL TRIAL REGISTRATION: NCT02164526 at https://clinicaltrials.gov .


Assuntos
Insuficiência Cardíaca/complicações , Hemodinâmica , Hipertensão Pulmonar/etiologia , Circulação Pulmonar , Idoso , Cateterismo Cardíaco , China , Doença Crônica , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/mortalidade , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo
6.
BMC Syst Biol ; 11(Suppl 5): 92, 2017 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-28984200

RESUMO

BACKGROUND: Previous studies suggested that cancer cells possess traits reminiscent of the biological mechanisms ascribed to normal embryonic stem cells (ESCs) regulated by MYC and Polycomb repressive complex 2 (PRC2). Several poorly differentiated adult tumors showed preferentially high expression levels in targets of MYC, coincident with low expression levels in targets of PRC2. This paper will reveal this ESC-like cancer signature in high-risk neuroblastoma (HR-NB), the most common extracranial solid tumor in children. METHODS: We systematically assembled genomic variants, gene expression changes, priori knowledge of gene functions, and clinical outcomes to identify prognostic multigene signatures. First, we assigned a new, individualized prognostic index using the relative expressions between the poor- and good-outcome signature genes. We then characterized HR-NB aggressiveness beyond these prognostic multigene signatures through the imbalanced effects of MYC and PRC2 signaling. We further analyzed Retinoic acid (RA)-induced HR-NB cells to model tumor cell differentiation. Finally, we performed in vitro validation on ZFHX3, a cell differentiation marker silenced by PRC2, and compared cell morphology changes before and after blocking PRC2 in HR-NB cells. RESULTS: A significant concurrence existed between exons with verified variants and genes showing MYCN-dependent expression in HR-NB. From these biomarker candidates, we identified two novel prognostic gene-set pairs with multi-scale oncogenic defects. Intriguingly, MYC targets over-represented an unfavorable component of the identified prognostic signatures while PRC2 targets over-represented a favorable component. The cell cycle arrest and neuronal differentiation marker ZFHX3 was identified as one of PRC2-silenced tumor suppressor candidates. Blocking PRC2 reduced tumor cell growth and increased the mRNA expression levels of ZFHX3 in an early treatment stage. This hypothesis-driven systems bioinformatics work offered novel insights into the PRC2-mediated tumor cell growth and differentiation in neuroblastoma, which may exert oncogenic effects together with MYC regulation. CONCLUSION: Our results propose a prognostic effect of imbalanced MYC and PRC2 moderations in pediatric HR-NB for the first time. This study demonstrates an incorporation of genomic landscapes and transcriptomic profiles into the hypothesis-driven precision prognosis and biomarker discovery. The application of this approach to neuroblastoma, as well as other cancer more broadly, could contribute to reduced relapse and mortality rates in the long term.


Assuntos
Perfilação da Expressão Gênica , Genômica , Células-Tronco Neoplásicas/patologia , Neuroblastoma/genética , Neuroblastoma/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Criança , Éxons/genética , Inativação Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Neuroblastoma/diagnóstico , Neuroblastoma/patologia , Complexo Repressor Polycomb 2/deficiência , Complexo Repressor Polycomb 2/genética , Prognóstico , Risco
7.
Sci Rep ; 7(1): 41, 2017 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-28246384

RESUMO

c-Myc dysregulation is hypothesized to account for the 'stemness' - self-renewal and pluripotency - shared between embryonic stem cells (ESCs) and adult aggressive tumours. High-risk neuroblastoma (HR-NB) is the most frequent, aggressive, extracranial solid tumour in childhood. Using HR-NB as a platform, we performed a network analysis of transcriptome data and presented a c-Myc subnetwork enriched for genes previously reported as ESC-like cancer signatures. A subsequent drug-gene interaction analysis identified a pharmacogenomic agent that preferentially interacted with this HR-NB-specific, ESC-like signature. This agent, Roniciclib (BAY 1000394), inhibited neuroblastoma cell growth and induced apoptosis in vitro. It also repressed the expression of the oncogene c-Myc and the neural ESC marker CDK2 in vitro, which was accompanied by altered expression of the c-Myc-targeted cell cycle regulators CCND1, CDKN1A and CDKN2D in a time-dependent manner. Further investigation into this HR-NB-specific ESC-like signature in 295 and 243 independent patients revealed and validated the general prognostic index of CDK2 and CDKN3 compared with CDKN2D and CDKN1B. These findings highlight the very potent therapeutic benefits of Roniciclib in HR-NB through the targeting of c-Myc-regulated, ESC-like tumorigenesis. This work provides a hypothesis-driven systems computational model that facilitates the translation of genomic and transcriptomic signatures to molecular mechanisms underlying high-risk tumours.


Assuntos
Antineoplásicos/farmacologia , Genes myc , Neuroblastoma/genética , Pirimidinas/farmacologia , Sulfóxidos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Células-Tronco Embrionárias/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Mutação , Células-Tronco Neoplásicas/metabolismo , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Testes Farmacogenômicos , Risco , Transcriptoma
8.
J Exp Med ; 212(10): 1487-95, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26304964

RESUMO

Eicosanoids are inflammatory mediators that play a key but incompletely understood role in linking the innate and adaptive immune systems. Here, we show that cytotoxic effector T cells (CTLs) are capable of both producing and responding to cysteinyl leukotrienes (CystLTs), allowing for the killing of target cells in a T cell receptor-independent manner. This process is dependent on the natural killer receptor NKG2D and exposure to IL-15, a cytokine induced in distressed tissues. IL-15 and NKG2D signaling drives the up-regulation of key enzymes implicated in the synthesis of CystLTs, as well as the expression of CystLT receptors, suggesting a positive feedback loop. Finally, although the CystLT pathway has been previously linked to various allergic disorders, we provide unexpected evidence for its involvement in the pathogenesis of celiac disease (CD), a T helper 1 cell-mediated enteropathy induced by gluten. These findings provide new insights into the cytolytic signaling pathway of NKG2D and the pathogenesis of organ-specific immune disorders. Furthermore, they suggest that the blockade of CystLT receptors may represent a potent therapeutic target for CD or potentially other autoimmune disorders in which NKG2D has been implicated.


Assuntos
Doença Celíaca/imunologia , Cisteína/metabolismo , Interleucina-15/imunologia , Leucotrienos/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Linfócitos T Citotóxicos/imunologia , Adulto , Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/metabolismo , Estudos de Casos e Controles , Doença Celíaca/fisiopatologia , Células Cultivadas , Cisteína/imunologia , Feminino , Humanos , Interleucina-15/metabolismo , Leucotrienos/imunologia , Masculino , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores de Leucotrienos/genética , Receptores de Leucotrienos/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Regulação para Cima
9.
J Immunol ; 193(2): 610-6, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24935923

RESUMO

The NKG2 family of NK receptors includes activating and inhibitory members. With the exception of the homodimer-forming NKG2D, NKG2 receptors recognize the nonclassical MHC class I molecule HLA-E, and they can be subdivided into two groups: those that associate with and signal through DAP12 to activate cells, and those that contain an ITIM motif to promote inhibition. The function of NKG2 family member NKG2E is unclear in humans, and its surface expression has never been conclusively established, largely because there is no Ab that binds specifically to NKG2E. Seeking to determine a role for this molecule, we chose to investigate its expression and ability to form complexes with intracellular signaling molecules. We found that NKG2E was capable of associating with CD94 and DAP12 but that the complex was retained intracellularly at the endoplasmic reticulum instead of being expressed on cell surfaces, and that this localization was dependent on a sequence of hydrophobic amino acids in the extracellular domain of NKG2E. Because this particular sequence has emerged and been conserved selectively among higher order primates evolutionarily, this observation raises the intriguing possibility that NKG2E may function as an intracellular protein.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Citoplasma/metabolismo , Proteínas de Membrana/metabolismo , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Subfamília D de Receptores Semelhantes a Lectina de Células NK/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Sequência de Aminoácidos , Aminoácidos/química , Aminoácidos/genética , Aminoácidos/metabolismo , Animais , Sítios de Ligação/genética , Western Blotting , Linhagem Celular , Retículo Endoplasmático/metabolismo , Células HEK293 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Membrana/genética , Microscopia Confocal , Dados de Sequência Molecular , Mutação , Subfamília C de Receptores Semelhantes a Lectina de Células NK/classificação , Subfamília C de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília D de Receptores Semelhantes a Lectina de Células NK/genética , Filogenia , Ligação Proteica , Homologia de Sequência de Aminoácidos
10.
PLoS One ; 8(9): e76292, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24086722

RESUMO

NK cells are large granular lymphocytes that form a critical component of the innate immune system, whose functions include the killing of cells expressing stress-induced molecules. It is increasingly accepted that despite being considered prototypical effector cells, NK cells require signals to reach their full cytotoxic potential. We previously showed that IL-15 is capable of arming CD8 effector T cells to kill independently of their TCR via NKG2D in a cPLA2-dependent process. As NK cells also express NKG2D, we wanted to investigate whether this pathway functioned in an analogous manner and if resting NK cells could be primed to the effector phase by IL-15. Furthermore, to establish relevance to human disease we studied a possible role for this pathway in the pathogenesis of psoriatic arthritis, since there are aspects of this disease that suggest a potential effector role for the innate immune system. We found that PsA patients had upregulated IL-15 and MIC in their affected synovial tissues, and that this unique inflammatory environment enabled NK cell activation and killing via NKG2D and cPLA2. Moreover, we were able to reproduce the phenotype of joint NK cells from blood NK cells by incubating them with IL-15. Altogether, these findings suggest a destructive role for NK cells when activated by environmental stress signals during the pathogenesis of PsA and demonstrate that IL-15 is capable of priming resting NK cells in tissues to the effector phase.


Assuntos
Artrite Psoriásica/imunologia , Regulação da Expressão Gênica/imunologia , Interleucina-15/imunologia , Células Matadoras Naturais/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Fosfolipases A2 Citosólicas/metabolismo , Transdução de Sinais/imunologia , Artrite Psoriásica/metabolismo , Citocinas/genética , Citocinas/metabolismo , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Interleucina-15/metabolismo , Células Matadoras Naturais/metabolismo , RNA Interferente Pequeno/genética , Transfecção
11.
J Biol Chem ; 284(47): 32353-8, 2009 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-19723627

RESUMO

The male hormone androgen is a growth/survival factor for its target tissues or organs. Yet, the underlying mechanism is incompletely understood. Here, we report that androgen via p21 inhibits tumor necrosis factor alpha-induced JNK activation and apoptosis. Inhibition by androgen requires the transcription activity of androgen receptor (AR) and de novo protein synthesis. Androgen.AR induces expression of p21 that in turn inhibits tumor necrosis factor alpha-induced JNK and apoptosis. Furthermore, genetic interruption of p21 alleles abolishes the inhibition by androgen. Our results reveal a novel cross-talk between androgen x AR and JNK, thereby providing a molecular mechanism underlying the survival function of androgen.


Assuntos
Androgênios/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação Neoplásica da Expressão Gênica , MAP Quinase Quinase 4/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Alelos , Apoptose , Linhagem Celular Tumoral , Ativação Enzimática , Humanos , Masculino , Modelos Biológicos , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Transcrição Gênica
12.
J Exp Med ; 206(3): 707-19, 2009 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-19237603

RESUMO

IL-15 and NKG2D promote autoimmunity and celiac disease by arming cytotoxic T lymphocytes (CTLs) to cause tissue destruction. However, the downstream signaling events underlying these functional properties remain unclear. Here, we identify cytosolic phospholipase A(2) (cPLA(2)) as a central molecule in NKG2D-mediated cytolysis in CTLs. Furthermore, we report that NKG2D induces, upon recognition of MIC(+) target cells, the release of arachidonic acid (AA) by CTLs to promote tissue inflammation in association with target killing. Interestingly, IL-15, which licenses NKG2D-mediated lymphokine killer activity in CTLs, cooperates with NKG2D to induce cPLA(2) activation and AA release. Finally, cPLA(2) activation in intraepithelial CTLs of celiac patients provides an in vivo pathophysiological dimension to cPLA(2) activation in CTLs. These results reveal an unrecognized link between NKG2D and tissue inflammation, which may underlie the emerging role of NKG2D in various immunopathological conditions and define new therapeutic targets.


Assuntos
Doença Celíaca/enzimologia , Doença Celíaca/imunologia , Interleucina-15/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Fosfolipases A2 Citosólicas/metabolismo , Linfócitos T Citotóxicos/enzimologia , Ácido Araquidônico/metabolismo , Doença Celíaca/patologia , Degranulação Celular , Citotoxicidade Imunológica , Ativação Enzimática , Células Epiteliais/enzimologia , Células Epiteliais/patologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Modelos Imunológicos , Fosforilação , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Linfócitos T Citotóxicos/fisiologia , Regulação para Cima
13.
Cell Host Microbe ; 4(4): 350-61, 2008 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-18854239

RESUMO

Educating dendritic cells (DC) to become tolerogenic DC, which promote regulatory IL-10 immune responses, represents an effective immune evasion strategy for pathogens. Yersinia pestis virulence factor LcrV is reported to induce IL-10 production via interaction with Toll-like receptor (TLR) 2. However, TLR2-/- mice are not protected against subcutaneous plague infection. Using complementary in vitro and in vivo approaches and LcrV as a model, we show that TLR6 associates with TLR2 to induce tolerogenic DC and regulatory type-1 T cells selectively secreting IL-10. In contrast, TLR1 heterodimerizes with TLR2 to promote proinflammatory IL-12p40 cytokine, producing DC and inflammatory T cell differentiation. LcrV specifically hijacks the TLR2/6 pathway to stimulate IL-10 production, which blocks host protective inflammatory responses. These results explain why TLR2 can mediate both pro- and anti-inflammatory responses and identify TLR6 as a distinct receptor driving regulatory IL-10 responses.


Assuntos
Antígenos de Bactérias/imunologia , Diferenciação Celular , Células Dendríticas/imunologia , Fatores Imunológicos/farmacologia , Peste/imunologia , Proteínas Citotóxicas Formadoras de Poros/imunologia , Receptor 6 Toll-Like/imunologia , Fatores de Virulência/imunologia , Yersinia pestis/imunologia , Animais , Contagem de Colônia Microbiana , Interleucina-10/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peste/microbiologia , Análise de Sobrevida , Linfócitos T Reguladores/imunologia , Yersinia pestis/patogenicidade
14.
Mol Cell Biol ; 26(5): 1908-16, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16479009

RESUMO

Androgen and its receptor (AR) have been reported to have pro- or antiapoptotic functions. However, the underlying molecular mechanism is incompletely understood. We report here that androgen and AR promote Bax-mediated apoptosis in prostate cancer cells. UV irradiation and ectopic expression of Bax induce apoptosis in AR-positive, but not AR-negative prostate cancer cells. UV- and Bax-induced apoptosis is abrogated in AR-positive cells that express small interference RNA (siRNA) of AR and is sensitized by reintroduction of AR into AR-negative cells. Although AR is able to promote Bax-mediated apoptosis independently of androgen, the promotion by AR can be further potentiated by androgen via AR-dependent transcription activation. AR is essential for the translocation of Bax to mitochondria in UV- or Bax-induced apoptosis. Inhibition of Bax expression by Bax siRNA suppresses UV-induced apoptosis in AR-positive cells. In addition, introduction of AR into AR-negative prostate cancer cells upregulates expression levels of the BH3-only protein Noxa, whereas inhibition of Noxa expression reduces the promotion by AR on UV-induced apoptosis. Thus, our results reveal a novel cross talk between the androgen/AR hormonal signaling pathway and the intrinsic apoptotic death pathway that determines the sensitivity of stress-induced apoptosis in prostate cancer cells.


Assuntos
Androgênios/farmacologia , Apoptose/fisiologia , Receptores Androgênicos/metabolismo , Proteína X Associada a bcl-2/metabolismo , Antagonistas de Androgênios/farmacologia , Androgênios/metabolismo , Anilidas/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Humanos , Masculino , Metribolona/farmacologia , Mitocôndrias/metabolismo , Nitrilas , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Transporte Proteico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores Androgênicos/efeitos dos fármacos , Compostos de Tosil , Transcrição Gênica , Células Tumorais Cultivadas , Raios Ultravioleta , Proteína X Associada a bcl-2/efeitos dos fármacos , Proteína X Associada a bcl-2/genética
15.
Mol Cell ; 13(3): 329-40, 2004 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-14967141

RESUMO

JNK has been suggested to be proapoptotic, antiapoptotic, or have no role in apoptosis depending on the cell type and stimulus used. The precise mechanism of JNK action, under conditions when it promotes cell survival, is not entirely clear. Here, we report that JNK is required for IL-3-mediated cell survival through phosphorylation and inactivation of the proapoptotic Bcl-2 family protein BAD. IL-3 withdrawal-induced apoptosis is promoted by inhibition of JNK but suppressed by expression of a constitutively active JNK. JNK phosphorylates BAD at threonine 201, thereby inhibiting BAD association with the antiapoptotic molecule BCL-X(L). IL-3 induces BAD phosphorylation at threonine 201, and replacement of threonine 201 by alanine generates a BAD mutant, which promotes IL-3 withdrawal-induced apoptosis. Thus, our results provide a molecular mechanism by which JNK contributes to cell survival.


Assuntos
Apoptose/fisiologia , Proteínas de Transporte/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Alanina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteínas de Transporte/genética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Interleucina-3/metabolismo , Interleucina-3/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno , Camundongos , Mutação/genética , Fosforilação , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Treonina/metabolismo , Proteína de Morte Celular Associada a bcl , Proteína bcl-X
16.
Mol Cell Biol ; 22(24): 8571-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12446776

RESUMO

The proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha) regulates immune responses, inflammation, and programmed cell death (apoptosis). TNF-alpha exerts its biological activities by activating multiple signaling pathways, including IkappaB kinase (IKK), c-Jun N-terminal protein kinase (JNK), and caspases. IKK activation inhibits apoptosis through the transcription factor NF-kappaB, whose target genes include those that encode inhibitors of both caspases and JNK. Despite activation of the antiapoptotic IKK/NF-kappaB pathway, TNF-alpha is able to induce apoptosis in cells sensitive to it, such as human breast carcinoma MCF-7 and mouse fibroblast LM cells. The molecular mechanism underlying TNF-alpha-induced apoptosis is incompletely understood. Here we report that in TNF-alpha-sensitive cells activation of the IKK/NF-kappaB pathway fails to block TNF-alpha-induced apoptosis, although its inactivation still promotes TNF-alpha-induced apoptosis. Interestingly, TNF-alpha-induced apoptosis is suppressed by inhibition of the JNK pathway but promoted by its activation. Furthermore, activation of JNK by TNF-alpha was transient in TNF-alpha-insensitive cells but prolonged in sensitive cells. Conversion of JNK activation from prolonged to transient suppressed TNF-alpha-induced apoptosis. Thus, absence of NF-kappaB-mediated inhibition of JNK activation contributes to TNF-alpha-induced apoptosis.


Assuntos
Apoptose/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular , Ativação Enzimática , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Interleucina-1/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Inibidor de NF-kappaB alfa , NF-kappa B/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Acetato de Tetradecanoilforbol/metabolismo
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