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1.
Obes Surg ; 31(10): 4452-4460, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34357533

RESUMO

PURPOSE: To estimate the association of emotional distress with both consumption of energy-dense micronutrient-poor foods (EDF) and body mass index (BMI) and the association between EDF consumption and change in BMI, during COVID-19 pandemic in patients with prior bariatric surgery. MATERIALS AND METHODS: This cross-sectional study applied an online structured questionnaire to 75 postoperative bariatric patients during the first Portuguese lockdown. Emotional distress was assessed trough the Hospital Anxiety and Depression Scale (HADS) and dietary intake was evaluated by Food Frequency Questionnaire (FFQ). Self-reported BMI prior to and at the end of confinement was used to compute BMI change. Pre-surgery BMI was computed from measured height and weight from clinical records. RESULTS: After adjustment for education, sex, time since surgery, pre-surgery BMI, and exercise practice, moderate/severe scores in HADS were significantly positively associated with consumption of EDF (ẞ = 0.799; 95% CI: 0.051, 1.546), but not with BMI. Daily EDF consumption significantly increased the odds of maintaining/increasing BMI (OR = 3.34; 95% CI: 1.18, 9.45), instead of decreasing it (reference). Sweets consumption was the only subcategory of EDF significantly positively associated with the odds of a worse outcome in BMI change (OR = 4.01; 95% CI: 1.13, 14.22). CONCLUSIONS: Among postoperative bariatric patients, higher reported levels of emotional distress during confinement are associated with increased EDF consumption. Increased EDF consumption during confinement, particularly sweets, is associated with higher odds of bariatric patients not decreasing their BMI. Additional effort is needed to address inadequate lifestyle behaviors among these patients in the context of the COVID-19 pandemic.


Assuntos
Cirurgia Bariátrica , COVID-19 , Obesidade Mórbida , Angústia Psicológica , Índice de Massa Corporal , Controle de Doenças Transmissíveis , Estudos Transversais , Humanos , Obesidade Mórbida/cirurgia , Pandemias , SARS-CoV-2
3.
Sci Rep ; 9(1): 6136, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992475

RESUMO

Histone deacetylases (HDACs) are involved in diverse cellular regulatory mechanisms including non-canonical functions outside the chromatin environment. Several publications have demonstrated that selective HDAC inhibitors (HDACi) can influence tumor immunogenicity and the functional activity of specific immune cells. In particular, the selective inhibition of HDAC6 has been reported to decrease tumor growth in several malignancies. However, there is still no clarity about the cellular components mediating this effect. In this study, we evaluated the HDAC6i Nexturastat A as a priming agent to facilitate the transition of the tumor microenvironment from "cold" to "hot", and potentially augment immune check-point blockade therapies. This combination modality demonstrated to significantly reduce tumor growth in syngeneic melanoma tumor models. Additionally, we observed a complete neutralization of the up-regulation of PD-L1 and other immunosuppressive pathways induced by the treatment with anti-PD-1 blockade. This combination also showed profound changes in the tumor microenvironment such as enhanced infiltration of immune cells, increased central and effector T cell memory, and a significant reduction of pro-tumorigenic M2 macrophages. The evaluation of individual components of the tumor microenvironment suggested that the in vivo anti-tumor activity of HDAC6i is mediated by its effect on tumor cells and tumor-associated macrophages, and not directly over T cells. Overall, our results indicate that selective HDAC6i could be used as immunological priming agents to sensitize immunologically "cold" tumors and subsequently improve ongoing immune check-point blockade therapies.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/uso terapêutico , Macrófagos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Anti-Inflamatórios/uso terapêutico , Antígeno B7-H1/imunologia , Desacetilase 6 de Histona/imunologia , Tolerância Imunológica/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia , Microambiente Tumoral/efeitos dos fármacos
4.
Cancer ; 120(15): 2343-51, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24752945

RESUMO

BACKGROUND: This cooperative group adjuvant phase 2 trial in patients with completely resected stage I non-small cell lung cancer with tumor diameters measuring ≥ 2 cm was designed to assess the feasibility and preliminary efficacy of assigning patients to therapy or observation using a molecularly based decision algorithm. METHODS: At least a lobectomy and sampling of recommended mediastinal lymph node stations, good Zubrod performance status, adequate organ function, and a formalin-fixed and paraffin-embedded tumor specimen were required. Excision repair cross-complementing group 1 (ERCC1) and ribonucleotide reductase M1 (RRM1) were analyzed using immunofluorescence-based in situ automated quantitative image analysis and categorized as high or low using prespecified cutoff values. Patients with high ERCC1 and RRM1 were assigned to observation and all others to 4 cycles of cisplatin and gemcitabine. Feasibility was defined as treatment assignment within 84 days from surgery in > 85% of patients. Secondary objectives were to estimate the 2-year survival. RESULTS: Treatment assignment met the feasibility criteria in 88% of eligible patients (71 of 81 patients). The collective 2-year disease-free and overall survival rates were 80% and 96%, respectively. Protein levels for RRM1 fell within the previously established range, ERCC1 levels were slightly lower than expected, and they were significantly correlated (correlation coefficient, 0.4). The rates of assignment of patients to observation (22%) and chemotherapy (78%) were as expected. CONCLUSIONS: Gene expression analysis for treatment assignment is feasible. Survival results are encouraging and require future validation. Real-time performance of quantitative in situ ERCC1 and RRM1 analysis requires further development.


Assuntos
Algoritmos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Proteínas de Ligação a DNA/metabolismo , Tomada de Decisões , Endonucleases/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Medicina de Precisão , Ribonucleosídeo Difosfato Redutase , Resultado do Tratamento , Proteínas Supressoras de Tumor
5.
Br J Haematol ; 157(5): 553-63, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22449149

RESUMO

We conducted a Phase 1/2 study of bortezomib administered in combination with high-dose melphalan followed by tandem autologous transplants in patients with primary resistant multiple myeloma. Thirty patients received two cycles of salvage bortezomib followed by stem cell mobilization with granulocyte colony-stimulating factor and harvest. Melphalan 100 mg/m(2) per day on two consecutive days was administered, immediately followed by one dose of bortezomib (dose escalation) and stem cell infusion. The median beta 2-microglobulin was 4·35 mg/l (range: 1·8-11·4); albumin was 37 g/l (range: 3·1-4·9); high-risk karyotypes were noted in 45% of patients. The maximum planned dose of bortezomib at 1·3 mg/m(2) was well tolerated and a formal maximum tolerated dose was not determined. The peak of best overall response (≥partial response) and complete response rates after tandem transplants were 84% and 36%, respectively. With a median follow-up of 48 months, the median progression-free survival was 15 [95% confidence interval (CI): 11-21] months and the median overall survival was 35 (95% CI: 22-43) months. Correlative studies demonstrated decreased expression of BRCA2 (P = 0·0072) and FANCF (P = 0·0458) mRNA following bortezomib treatment. Bortezomib combined with high-dose melphalan is a well-tolerated conditioning with some activity in patients with resistant myeloma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo/terapia , Terapia de Salvação , Condicionamento Pré-Transplante , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ácidos Borônicos/administração & dosagem , Bortezomib , Progressão da Doença , Proteínas de Grupos de Complementação da Anemia de Fanconi/metabolismo , Feminino , Humanos , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/mortalidade , Pirazinas/administração & dosagem , Transdução de Sinais , Análise de Sobrevida , Transplante Autólogo , Resultado do Tratamento
6.
Mol Cell Proteomics ; 10(11): M110.005520, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21846842

RESUMO

The emergence of acquired drug resistance results from multiple compensatory mechanisms acting to prevent cell death. Simultaneous monitoring of proteins involved in drug resistance is a major challenge for both elucidation of the underlying biology and development of candidate biomarkers for assessment of personalized cancer therapy. Here, we have utilized an integrated analytical platform based on SDS-PAGE protein fractionation prior to liquid chromatography coupled to multiple reaction monitoring mass spectrometry, a versatile and powerful tool for targeted quantification of proteins in complex matrices, to evaluate a well-characterized model system of melphalan resistance in multiple myeloma (MM). Quantitative assays were developed to measure protein expression related to signaling events and biological processes relevant to melphalan resistance in multiple myeloma, specifically: nuclear factor-κB subunits, members of the Bcl-2 family of apoptosis-regulating proteins, and Fanconi Anemia DNA repair components. SDS-PAGE protein fractionation prior to liquid chromatography coupled to multiple reaction monitoring methods were developed for quantification of these selected target proteins in amounts of material compatible with direct translation to clinical specimens (i.e. less than 50,000 cells). As proof of principle, both relative and absolute quantification were performed on cell line models of MM to compare protein expression before and after drug treatment in naïve cells and in drug resistant cells; these liquid chromatography-multiple reaction monitoring results are compared with existing literature and Western blots. The initial stage of a systems biology platform for examining drug resistance in MM has been implemented in cell line models and has been translated to MM cells isolated from a patient. The ultimate application of this platform could assist in clinical decision-making for individualized patient treatment. Although these specific assays have been developed to monitor MM, these techniques are expected to have broad applicability in cancer and other types of disease.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Resistencia a Medicamentos Antineoplásicos , Melfalan/farmacologia , Mieloma Múltiplo/metabolismo , NF-kappa B/metabolismo , Antineoplásicos Alquilantes/uso terapêutico , Apoptose , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Proteínas de Grupos de Complementação da Anemia de Fanconi/metabolismo , Perfilação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Melfalan/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transdução de Sinais , Espectrometria de Massas por Ionização por Electrospray , Sindecana-1/metabolismo , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelB/genética , Fator de Transcrição RelB/metabolismo
7.
Cancer Res ; 69(24): 9367-75, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19934314

RESUMO

The Fanconi anemia/BRCA (FA/BRCA) DNA damage repair pathway plays a pivotal role in the cellular response to replicative stress induced by DNA alkylating agents and greatly influences drug response in cancer treatment. We recently reported that FA/BRCA genes are overexpressed and causative for drug resistance in human melphalan-resistant multiple myeloma cell lines. However, the transcriptional regulation of the FA/BRCA pathway is not understood. In this report, we describe for the first time a novel function of the NF-kappaB subunits, RelB/p50, as transcriptional activators of the FA/BRCA pathway. Specifically, our findings point to constitutive phosphorylation of IkappaB kinase alpha and subsequent alterations in FANCD2 expression and function as underlying events leading to melphalan resistance in repeatedly exposed multiple myeloma cells. Inhibiting NF-kappaB by small interfering RNA, blocking the IkappaB kinase complex with BMS-345541, or using the proteasome inhibitor bortezomib drastically reduced FA/BRCA gene expression and FANCD2 protein expression in myeloma cells, resulting in diminished DNA damage repair and enhanced melphalan sensitivity. Importantly, we also found that bortezomib decreases FA/BRCA gene expression in multiple myeloma patients. These results show for the first time that NF-kappaB transcriptionally regulates the FA/BRCA pathway and provide evidence for targeting Fanconi anemia-mediated DNA repair to enhance chemotherapeutic response and circumvent drug resistance in myeloma patients.


Assuntos
Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Anemia de Fanconi/metabolismo , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Ácidos Borônicos/farmacologia , Bortezomib , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Anemia de Fanconi/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/antagonistas & inibidores , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/biossíntese , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Melfalan/farmacologia , Mieloma Múltiplo/genética , NF-kappa B , Pirazinas/farmacologia , Quinoxalinas/farmacologia , Fator de Transcrição RelB/metabolismo
8.
J Biol Chem ; 284(25): 16752-16758, 2009 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-19406746

RESUMO

Hypoxia-inducible factor-1 (HIF-1) plays a central role in tumor progression by regulating genes involved in proliferation, glycolysis, angiogenesis, and metastasis. To improve our understanding of HIF-1 regulation by kinome, we screened a kinase-specific small interference RNA library using a hypoxia-response element (HRE) luciferase reporter assay under hypoxic conditions. This screen determined that depletion of cellular SMG-1 kinase most significantly modified cellular HIF-1 activity in hypoxia. SMG-1 is the newest and least studied member of the phosphoinositide 3-kinase-related kinase family, which consists of ATM, ATR, DNA-PKcs, mTOR, and SMG-1. We individually depleted members of the phosphoinositide 3-kinase-related kinase family, and only SMG-1 deficiency significantly augmented HIF-1 activity in hypoxia. We subsequently discovered that SMG-1 kinase activity was activated by hypoxia, and depletion of SMG-1 up-regulated MAPK activity under low oxygen. Suppressing cellular MAPK by silencing ERK1/2 or by treatment with U0126, a MAPK inhibitor, partially blocked the escalation of HIF-1 activity resulting from SMG-1 deficiency in hypoxic cells. Increased expression of SMG-1 but not kinase-dead SMG-1 effectively inhibited the activity of HIF-1alpha. In addition, cellular SMG-1 deficiency increased secretion of the HIF-1alpha-regulated angiogenic factor, vascular epidermal growth factor, and survival factor, carbonic anhydrase IX (CA9), as well as promoted the hypoxic cell motility. Taken together, we discovered that SMG-1 negatively regulated HIF-1alpha activity in hypoxia, in part through blocking MAPK activation.


Assuntos
Hipóxia Celular/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , RNA Interferente Pequeno/genética , Antígenos de Neoplasias/biossíntese , Anidrase Carbônica IX , Anidrases Carbônicas/biossíntese , Hipóxia Celular/genética , Linhagem Celular Tumoral , Movimento Celular , Biblioteca Gênica , Células HeLa , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases , Inibidores de Fosfoinositídeo-3 Quinase , Análise Serial de Proteínas , Proteínas Serina-Treonina Quinases , Proteoma , Fator A de Crescimento do Endotélio Vascular/biossíntese
9.
J Biol Chem ; 283(19): 13174-84, 2008 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-18326048

RESUMO

The human suppressor of morphogenesis in genitalia-1 (hSMG-1) protein kinase plays dual roles in mRNA surveillance and genotoxic stress response pathways in human cells. Here, we report that small interfering RNA-mediated depletion of hSMG-1, but not ATM, ATR, hUpf1, or hUpf2, in human U2OS osteosarcoma cells markedly increases the magnitude and accelerates the rate of apoptosis induced by tumor necrosis factor-alpha (TNFalpha) stimulation. The increase in TNFalpha-mediated cell killing observed in hSMG-1-depleted cells is not related to the suppression of nonsense-mediated mRNA decay or to the inhibition of TNFalpha-induced NF-kappaB activation. Rather, we observed that loss of hSMG-1 accelerates the degradation of the long form of the FLICE-inhibitory protein (FLIP(L)), an inhibitor of death-inducing signaling complex-mediated caspase-8 activation, in TNFalpha-treated cells. These results suggest that hSMG-1 plays an important role in cell survival during TNFalpha-induced stress.


Assuntos
Apoptose/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Linhagem Celular Tumoral , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/metabolismo , Humanos , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/genética , Biossíntese de Proteínas/genética , Proteínas Serina-Treonina Quinases , RNA Mensageiro/genética , RNA Interferente Pequeno/genética
10.
Exp Cell Res ; 306(1): 24-34, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15878329

RESUMO

The Golgi associated retrograde protein complex (GARP) or Vps fifty-three (VFT) complex is part of cellular inter-compartmental transport systems. Here we report the identification of the VFT tethering factor complex and its interactions in mammalian cells. Subcellular fractionation shows that human Vps proteins are found in the smooth membrane/Golgi fraction but not in the cytosol. Immunostaining of human Vps proteins displays a vesicular distribution most concentrated at the perinuclear envelope. Co-staining experiments with endosomal markers imply an endosomal origin of these vesicles. Significant accumulation of VFT complex positive endosomes is found in the vicinity of the Trans Golgi Network area. This is in accordance with a putative role in Golgi associated transport processes. In Saccharomyces cerevisiae, GARP is the main effector of the small GTPase Ypt6p and interacts with the SNARE Tlg1p to facilitate membrane fusion. Accordingly, the human homologue of Ypt6p, Rab6, specifically binds hVps52. In human cells, the "orphan" SNARE Syntaxin 10 is the genuine binding partner of GARP mediated by hVps52. This reveals a previously unknown function of human Syntaxin 10 in membrane docking and fusion events at the Golgi. Taken together, GARP shows significant conservation between various species but diversification and specialization result in important differences in human cells.


Assuntos
Complexo de Golgi/fisiologia , Complexos Multiproteicos/fisiologia , Proteínas de Transporte Vesicular/fisiologia , Animais , Células COS , Linhagem Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Clonagem Molecular , Vesículas Citoplasmáticas/metabolismo , DNA Complementar/química , DNA Complementar/genética , Cães , Expressão Gênica/genética , Complexo de Golgi/metabolismo , Humanos , Complexo Principal de Histocompatibilidade/genética , Complexo Principal de Histocompatibilidade/fisiologia , Proteínas de Membrana/metabolismo , Microscopia Confocal , Dados de Sequência Molecular , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Ligação Proteica , Transporte Proteico , Proteínas/genética , Proteínas/metabolismo , Proteínas/fisiologia , Proteínas Qa-SNARE , Análise de Sequência de DNA , Transfecção , Vesículas Transportadoras/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
11.
Mol Cell ; 14(5): 585-98, 2004 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-15175154

RESUMO

Members of the PI 3-kinase-related kinase (PIKK) family function in mitogenic and stress-induced signaling pathways in eukaryotic cells. Here, we characterize the newest PIKK family member, hSMG-1, as a genotoxic stress-activated protein kinase that displays some functional overlap with the related kinase, ATM, in human cells. Both ATM and hSMG-1 phosphorylate Ser/Thr-Gln-containing target sequences in the checkpoint protein p53 and the nonsense-mediated mRNA decay (NMD) protein hUpf1. Expression of hSMG-1 is required for optimal p53 activation after cellular exposure to genotoxic stress, and depletion of hSMG-1 leads to spontaneous DNA damage and increased sensitivity to ionizing radiation (IR). Moreover, IR exposure triggers hUpf1 phosphorylation at Ser/Thr-Gln motifs, and both ATM and hSMG-1 contribute to these phosphorylation events. Finally, NMD is suppressed in hSMG-1- but not ATM-deficient cells. These results indicate that hSMG-1 plays important roles in the maintenance of both genome and transcriptome integrity in human cells.


Assuntos
Dano ao DNA/genética , Proteínas Quinases/fisiologia , Estabilidade de RNA/genética , RNA Mensageiro/metabolismo , Motivos de Aminoácidos/fisiologia , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular , Dano ao DNA/efeitos da radiação , Proteínas de Ligação a DNA , Instabilidade Genômica/genética , Instabilidade Genômica/efeitos da radiação , Células HeLa , Humanos , Metaloendopeptidases , Dados de Sequência Molecular , Fosforilação , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Helicases , RNA Mensageiro/genética , Radiação Ionizante , Transativadores/genética , Transativadores/metabolismo , Transcrição Gênica/genética , Transcrição Gênica/efeitos da radiação , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor
12.
Biochem J ; 381(Pt 1): 213-9, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15107016

RESUMO

Proteins of the NACHT [NAIP (neuronal apoptosis inhibitory protein), CIITA (MHC class II transcription activator), HET-E (incompatibility locus protein from Podospora anserina) and TP1 (telomerase-associated protein)] family may serve as critical pathogen-sensing and signal-transducing molecules within the innate immune system. In the present paper, we show that CLAN [CARD (caspase-recruitment domain), LRR (leucine-rich repeat) and NACHT domain-containing protein], a NACHT-containing protein originally demonstrated to bind and activate pro-caspase 1, is also capable of influencing the functions of other members of the NACHT family. Through heterotypic NACHT-domain interactions, CLAN was found to associate with Nod1, Nod2 and NAC [nucleotide-binding domain and CARD-containing protein; NALP1 (NACHT, LRR and PYRIN protein 1)] when co-expressed in HEK-293T (human embryonic kidney) cells. NF-kappaB (nuclear factor kappaB) reporter assays demonstrated that co-expression of either full-length CLAN or the NACHT domain of CLAN significantly inhibited NF-kappaB activation induced by Nod1 or Nod2 overexpression. In addition, co-expression of CLAN or the NACHT domain of CLAN with Nod1 or Nod2 inhibited the ability of these proteins to generate active IL-1beta (interleukin 1beta) through their association with pro-caspase 1. The NACHT domain of CLAN was demonstrated by co-immunoprecipitation experiments to bind all NACHT domains that were tested, including the NACHT domains from CLAN itself, Nod1, Nod2, cryopyrin, NAC, PAN2 [PAAD [pyrin, AIM (absent-in-melanoma), ASC (apoptosis-associated speck-like protein containing a CARD) and death-domain-like]- and NACHT-containing protein] and NAIP (neuronal apoptosis inhibitory protein). Finally, monocyte-expressed CLAN was found to associate with Nod2 following exposure to bacterial peptidoglycan, implying a regulatory role for interaction of these NACHT proteins in the innate immune response. These studies suggest that by mediating hetero-oligomerization, NACHT domains provide a means by which various NACHT-containing proteins may interact, creating protein-interaction networks that potentially modulate immune responses to invading pathogens.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Imunidade Inata , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Peptídeos/metabolismo , Proteínas Reguladoras de Apoptose , Proteínas Adaptadoras de Sinalização CARD , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/metabolismo , Linhagem Celular , Clonagem Molecular , DNA Complementar/genética , Humanos , Interleucina-1/metabolismo , Rim/embriologia , Substâncias Macromoleculares , Dados de Sequência Molecular , Monócitos/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Proteína Inibidora de Apoptose Neuronal , Proteína Adaptadora de Sinalização NOD1 , Proteína Adaptadora de Sinalização NOD2 , Núcleosídeo-Fosfato Quinase/metabolismo , Peptidoglicano/metabolismo , Isoformas de Proteínas/metabolismo , Proteínas Quinases/metabolismo , Estrutura Terciária de Proteína , Proteína Serina-Treonina Quinase 2 de Interação com Receptor
13.
J Biol Chem ; 277(38): 35333-40, 2002 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-12093792

RESUMO

PAAD domains are found in diverse proteins of unknown function and are structurally related to a superfamily of protein interaction modules that includes death domains, death effector domains, and Caspase activation and recruitment domains. Using bioinformatics strategies, cDNAs were identified that encode a novel protein of 110 kDa containing a PAAD domain followed by a putative nucleotide-binding (NACHT) domain and several leucine-rich repeat domains. This protein thus resembles Cryopyrin, a protein implicated in hereditary hyperinflammation syndromes, and was termed PAN2 for PAAD and NACHT-containing protein 2. When expressed in HEK293 cells, PAN2 suppressed NF-kappaB induction by the cytokines tumor necrosis factor-alpha (TNFalpha) and interleukin-1beta (IL-1beta), suggesting that this protein operates at a point of convergence in these two cytokine signaling pathways. This PAN2-mediated suppression of NF-kappaB was evident both in reporter gene assays that measured NF-kappaB transcriptional activity and electromobility shift assays that measured NF-kappaB DNA binding activity. PAN2 also suppressed NF-kappaB induction resulting from overexpression of several adapter proteins and protein kinases involved in the TNF or IL-1 receptor signal transduction, including TRAF2, TRAF6, RIP, IRAK2, and NF-kappaB-inducing kinase as well as the IkappaB kinases IKKalpha and IKKbeta. PAN2 also inhibited the cytokine-mediated activation of IKKalpha and IKKbeta as measured by in vitro kinase assays. Furthermore, PAN2 association with IKKalpha was demonstrated by co-immunoprecipitation assays, suggesting a direct effect on the IKK complex. These observations suggest a role for PAN2 in modulating NF-kappaB activity in cells, thus providing the insights into the potential functions of PAAD family proteins and their roles in controlling inflammatory responses.


Assuntos
Interleucina-1/fisiologia , NF-kappa B/biossíntese , Proteínas/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Primers do DNA , Ensaio de Desvio de Mobilidade Eletroforética , Ativação Enzimática , Humanos , Quinase I-kappa B , Dados de Sequência Molecular , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas/química , Proteínas/genética , Proteínas Repressoras , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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