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1.
Clin Cancer Res ; 28(13): 2854-2864, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35522533

RESUMO

PURPOSE: We designed a comprehensive multiple myeloma targeted sequencing panel to identify common genomic abnormalities in a single assay and validated it against known standards. EXPERIMENTAL DESIGN: The panel comprised 228 genes/exons for mutations, 6 regions for translocations, and 56 regions for copy number abnormalities (CNA). Toward panel validation, targeted sequencing was conducted on 233 patient samples and further validated using clinical FISH (translocations), multiplex ligation probe analysis (MLPA; CNAs), whole-genome sequencing (WGS; CNAs, mutations, translocations), or droplet digital PCR (ddPCR) of known standards (mutations). RESULTS: Canonical immunoglobulin heavy chain translocations were detected in 43.2% of patients by sequencing, and aligned with FISH except for 1 patient. CNAs determined by sequencing and MLPA for 22 regions were comparable in 103 samples and concordance between platforms was R2 = 0.969. Variant allele frequency (VAF) for 74 mutations were compared between sequencing and ddPCR with concordance of R2 = 0.9849. CONCLUSIONS: In summary, we have developed a targeted sequencing panel that is as robust or superior to FISH and WGS. This molecular panel is cost-effective, comprehensive, clinically actionable, and can be routinely deployed to assist risk stratification at diagnosis or posttreatment to guide sequencing of therapies.


Assuntos
Mieloma Múltiplo , Variações do Número de Cópias de DNA , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/genética , Mutação , Translocação Genética , Sequenciamento Completo do Genoma
2.
Mol Cell ; 80(6): 1013-1024.e6, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33338401

RESUMO

Impaired DNA crosslink repair leads to Fanconi anemia (FA), characterized by a unique manifestation of bone marrow failure and pancytopenia among diseases caused by DNA damage response defects. As a germline disorder, why the hematopoietic hierarchy is specifically affected is not fully understood. We find that reprogramming transcription during hematopoietic differentiation results in an overload of genotoxic stress, which causes aborted differentiation and depletion of FA mutant progenitor cells. DNA damage onset most likely arises from formaldehyde, an obligate by-product of oxidative protein demethylation during transcription regulation. Our results demonstrate that rapid and extensive transcription reprogramming associated with hematopoietic differentiation poses a major threat to genome stability and cell viability in the absence of the FA pathway. The connection between differentiation and DNA damage accumulation reveals a novel mechanism of genome scarring and is critical to exploring therapies to counteract the aplastic anemia for the treatment of FA patients.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Reprogramação Celular/genética , Anemia de Fanconi/genética , Formaldeído/toxicidade , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/genética , Anemia de Fanconi/sangue , Anemia de Fanconi/patologia , Formaldeído/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/genética , Instabilidade Genômica/genética , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Células K562 , Transcrição Gênica
3.
Cell Discov ; 4: 28, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29900004

RESUMO

The histone variant H2A.Z is essential for maintaining embryonic stem cell (ESC) identity in part by keeping developmental genes in a poised bivalent state. However, how H2A.Z is deposited into the bivalent domains remains unknown. In mammals, two chromatin remodeling complexes, Tip60/p400 and SRCAP, exchange the canonical histone H2A for H2A.Z in the chromatin. Here we show that Glioma Amplified Sequence 41 (Gas41), a shared subunit of the two H2A.Z-depositing complexes, functions as a reader of histone lysine acetylation and recruits Tip60/p400 and SRCAP to deposit H2A.Z into specific chromatin regions including bivalent domains. The YEATS domain of Gas41 bound to acetylated histone H3K27 and H3K14 both in vitro and in cells. The crystal structure of the Gas41 YEATS domain in complex with the H3K27ac peptide revealed that, similar to the AF9 and ENL YEATS domains, Gas41 YEATS forms a serine-lined aromatic cage for acetyllysine recognition. Consistently, mutations in the aromatic residues of the Gas41 YEATS domain abrogated the interaction. In mouse ESCs, knockdown of Gas41 led to flattened morphology of ESC colonies, as the result of derepression of differentiation genes. Importantly, the abnormal morphology was rescued by expressing wild-type Gas41, but not the YEATS domain mutated counterpart that does not recognize histone acetylation. Mechanically, we found that Gas41 depletion led to reduction of H2A.Z levels and a concomitant reduction of H3K27me3 levels on bivalent domains. Together, our study reveals an essential role of the Gas41 YEATS domain in linking histone acetylation to H2A.Z deposition and maintenance of ESC identity.

4.
Genes Dev ; 32(1): 58-69, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29437725

RESUMO

Histone acetylation is associated with active transcription in eukaryotic cells. It helps to open up the chromatin by neutralizing the positive charge of histone lysine residues and providing binding platforms for "reader" proteins. The bromodomain (BRD) has long been thought to be the sole protein module that recognizes acetylated histones. Recently, we identified the YEATS domain of AF9 (ALL1 fused gene from chromosome 9) as a novel acetyl-lysine-binding module and showed that the ENL (eleven-nineteen leukemia) YEATS domain is an essential acetyl-histone reader in acute myeloid leukemias. The human genome encodes four YEATS domain proteins, including GAS41, a component of chromatin remodelers responsible for H2A.Z deposition onto chromatin; however, the importance of the GAS41 YEATS domain in human cancer remains largely unknown. Here we report that GAS41 is frequently amplified in human non-small cell lung cancer (NSCLC) and is required for cancer cell proliferation, survival, and transformation. Biochemical and crystal structural studies demonstrate that GAS41 binds to histone H3 acetylated on H3K27 and H3K14, a specificity that is distinct from that of AF9 or ENL. ChIP-seq (chromatin immunoprecipitation [ChIP] followed by high-throughput sequencing) analyses in lung cancer cells reveal that GAS41 colocalizes with H3K27ac and H3K14ac on the promoters of actively transcribed genes. Depletion of GAS41 or disruption of the interaction between its YEATS domain and acetylated histones impairs the association of histone variant H2A.Z with chromatin and consequently suppresses cancer cell growth and survival both in vitro and in vivo. Overall, our study identifies GAS41 as a histone acetylation reader that promotes histone H2A.Z deposition in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Amplificação de Genes , Genes cdc , Histonas/fisiologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Regiões Promotoras Genéticas , Domínios e Motivos de Interação entre Proteínas , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia
5.
Eur Arch Otorhinolaryngol ; 274(5): 2327-2334, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28229293

RESUMO

Age-related hearing loss (ARHL) is postulated to affect dementia. Our study aims to investigate the relationship between ARHL and the prevalence, and 10-year incidence of dementia in the Taiwan National Health Insurance Research Database (NHIRD). We selected patients diagnosed with ARHL from the NHIRD. A comparison cohort comprising of patients without ARHL was frequency-matched by age, sex, and co-morbidities, and the occurrence of dementia was evaluated in both cohorts. The ARHL cohort consisted of 4108 patients with ARHL and the control cohort consisted of 4013 frequency-matched patients without ARHL. The incidence of dementia [hazard ratio (HR), 1.30; 95% confidence interval (CI 1.14-1.49); P = 0.002] was higher among ARHL patients. Cox models showed that being female (HR, 1.34; 95% CI 1.07-1.68), as well as having co-morbidities, including chronic liver disease and cirrhosis, rheumatoid arthritis, hypertension, diabetes mellitus, stroke, head injury, chronic kidney disease, coronary artery disease, alcohol abuse/dependence, and tobacco abuse/dependence (HR, 1.27; 95% CI 1.11-1.45), were independent risk factors for dementia in ARHL patients. We found ARHL may be one of the early characteristics of dementia, and patients with hearing loss were at a higher risk of subsequent dementia. Clinicians should be more sensitive to dementia symptoms within the first 2 years following ARHL diagnosis. Further clinical studies of the relationship between dementia and ARHL may be necessary.


Assuntos
Demência , Presbiacusia , Idoso , Estudos de Coortes , Comorbidade , Demência/diagnóstico , Demência/epidemiologia , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Presbiacusia/diagnóstico , Presbiacusia/epidemiologia , Prevalência , Modelos de Riscos Proporcionais , Fatores de Risco , Taiwan/epidemiologia
6.
Soc Psychiatry Psychiatr Epidemiol ; 51(9): 1331-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27241318

RESUMO

OBJECTIVES: Bipolar disorder (BD) is a systemic inflammatory disease, and disrupted bone metabolism due to the inflammatory process can cause fracture. Despite evidence of an association between lower bone mineral density and an increased risk of fracture among patients with depression, schizophrenia, and anorexia nervosa, whether BD is a risk factor for subsequent fracture is unknown. To determine the association between BD and fracture and to examine the risk factors for fracture among patients with BD. METHODS: In this study, we enrolled patients diagnosed with BD from the Taiwan National Health Insurance Research Database. Patients newly diagnosed with BD (ICD-9-CM 296) from 2001 to 2008 were included in the BD cohort, and the date of the initial diagnosis of BD was used as the index date. The comparison cohort, comprising participants without BD, was frequency matched to the BD cohort by age, sex, and index year, and the occurrence of fracture was evaluated in both cohorts. RESULTS: The BD and comparison cohorts were comprised of 47,271 patients with BD and 1,89,084 frequency-matched participants without BD, respectively. The incidence of fracture was higher among patients with BD than among the controls. Cox models showed that BD was an independent risk factor for fracture irrespective of comorbidities [hazard ratio (HR) = 1.79, 95 % confidence interval (CI) = 1.73-1.84, p < .001]. CONCLUSION: Our study showed that patients with BD have a higher risk of subsequent fracture. Additional prospective clinical studies investigating the relationship between BD and fracture are warranted.


Assuntos
Transtorno Bipolar/epidemiologia , Fraturas Ósseas/epidemiologia , Adulto , Idoso , Estudos de Coortes , Comorbidade , Bases de Dados Factuais , Feminino , Humanos , Incidência , Classificação Internacional de Doenças , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Taiwan/epidemiologia
7.
J Appl Physiol (1985) ; 121(2): 457-65, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27339185

RESUMO

The purpose of this study was to evaluate the effects of exercise training on cardiac Fas receptor-dependent and mitochondria-dependent apoptotic pathways in ovariectomized rats. Histopathological analysis, TUNEL assay, and Western blotting were performed on the excised hearts from three groups of Sprague-Dawley rats, which were divided into a sham-operated group, a bilaterally ovariectomized group (OVX), and a bilaterally ovariectomized group that underwent treadmill running exercise for 60 min/day, 5 sessions/wk, for 10 wk (OVX-EX). The abnormal myocardial architecture, cardiac trichome-stained fibrosis and cardiac TUNEL-positive apoptotic cells in ovariectomized rats improved after exercise training. The protein levels of tumor necrosis factor-α, tumor necrosis factor receptor 1, Fas ligand, Fas receptors, Fas-associated death domain, activated caspase-8 and activated caspase-3 (Fas receptor-dependent apoptotic pathways), as well as t-Bid, Bad, Bak, Bax, cytosolic cytochrome c, activated caspase-9, and activated caspase-3 (mitochondria-dependent apoptotic pathways) were decreased in the OVX-EX group compared with the OVX group. Exercise training suppressed ovariectomy-induced cardiac Fas receptor-dependent and mitochondria-dependent apoptotic pathways in ovariectomized rat models. These findings might indicate a new therapeutic effect for exercise training to prevent cardiac apoptosis in menopausal or bilaterally oophorectomized women.


Assuntos
Proteínas Reguladoras de Apoptose/imunologia , Apoptose/imunologia , Isquemia Miocárdica/imunologia , Miocárdio/imunologia , Ovariectomia/efeitos adversos , Condicionamento Físico Animal/métodos , Animais , Feminino , Mitocôndrias Cardíacas/imunologia , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/prevenção & controle , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
8.
Graefes Arch Clin Exp Ophthalmol ; 254(3): 437-44, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26016811

RESUMO

PURPOSE: To analyze the influence of spectral-domain optical coherence tomography (SD-OCT) features on visual acuity changes in patients with idiopathic epiretinal membranes (ERMs). METHODS: Seventy-nine eyes of 71 patients were included in this study. SD-OCT was performed for all patients; data were collected upon ERM diagnosis and at the final visit. The patients were divided into subgroups based on their SD-OCT features. The initial best corrected visual acuity (BCVA) and changes in BCVA for each subgroup were compared. A multivariate analysis was performed to assess the factors associated with changes in BCVA. RESULTS: During a mean follow-up period of 20.78 months, the mean change in logMAR visual acuity was 0.052 ± 0.089. Eyes with inner segment/outer segment (IS/OS) junction disruption and cystoid macular edema (CME) had a significantly lower mean initial BCVA than those without disruption and CME (P = 0.036 and P = 0.012, respectively). However, only eyes with CME had significant changes in BCVA (P = .034). Multivariate analysis revealed the presence of CME as the only factor that had a significant correlation with VA changes. CONCLUSIONS: In patients with idiopathic ERMs, the presence of CME and IS/OS disruption detected by OCT correlated with a poorer initial BCVA. Most patients' visual acuity remained stable during follow-up. The presence of CME with OCT represented a predictor of the progression of visual acuity. These results may provide valuable clinical information regarding the management of patients with idiopathic ERMs. We demonstrated that the presence of CME and IS/OS disruption detected with OCT correlated with a poorer BCVA in idiopathic ERMs. The visual acuity of most patients was stable during the follow-up period. The presence of CME in OCT represented a predictor of vision deterioration for patients with idiopathic ERMs.


Assuntos
Membrana Epirretiniana/diagnóstico , Edema Macular/diagnóstico , Segmento Interno das Células Fotorreceptoras da Retina/patologia , Segmento Externo das Células Fotorreceptoras da Retina/patologia , Acuidade Visual/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Membrana Epirretiniana/fisiopatologia , Feminino , Seguimentos , Humanos , Edema Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia de Coerência Óptica
9.
Medicine (Baltimore) ; 94(51): e2333, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26705225

RESUMO

The risk of peptic ulcer disease (PUD) among patients with depression has raised concern. This study determined the association between depression and the subsequent development of PUD using claims data.Patients newly diagnosed with depression in 2000 to 2010 were identified as depression cohort from the Taiwan National Health Insurance Research Database. The comparison cohort was randomly selected from subjects without depression, frequency matched by age and gender and diagnosis date, with a size 2-fold of the size of the depression cohort. The incidence of PUD was evaluated for both cohorts by the end of 2011. We calculated the hazard ratios (HRs) and 95% confidence intervals (CIs) of PUD using the Cox proportional hazards regression model.The depression cohort consisted of 23,536 subjects (129,751 person-years), and the comparison cohort consisted of 47,069 subjects (285,592 person-years). The incidence of PUD was 2-fold higher in the depression cohort than in the comparison cohort (33.2 vs 16.8 per 1000 person-years) with an age adjusted HR of 1.97 (95% CI = 1.89-2.06) or a multivariable adjusted HR of 1.35 (95% CI = 1.29-1.42).Depression might increase the risk of developing PUD. Prospective clinical studies of the relationship between depression and PUD are warranted.


Assuntos
Depressão/epidemiologia , Úlcera Péptica/epidemiologia , Fatores Etários , Idoso , Ansiolíticos/administração & dosagem , Ansiolíticos/efeitos adversos , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Comorbidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Fumar/epidemiologia , Fatores Socioeconômicos , Taiwan/epidemiologia
10.
Medicine (Baltimore) ; 94(51): e2347, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26705230

RESUMO

Periodontitis is a systemic and chronic inflammatory disease associated with multiple physical conditions. Distress and depression are other problems affecting the progression of periodontitis. However, the causal relationship between depression and periodontitis has not been adequately investigated. This aim of this study was to determine the association between periodontitis and the subsequent development of depression.We identified 12,708 patients with newly diagnosed periodontitis from 2000 to 2005 and 50,832 frequency-matched individuals without periodontitis. Both groups were followed until diagnosed with depression, withdrawal from the National Health Insurance program, or the end of 2011. The association between periodontitis and depressio was analyzed using Cox proportional hazard regression models.The incidence density rate of depression was higher in the periodontitis group than in the nonperiodontitis group, with an adjusted hazard ratio of 1.73 (95% confidence interval 1.58-1.89) when adjusting for sex, age, and comorbidity. Cox models revealed that periodontitis was an independent risk factor for depression in patients, except for comorbidities of diabetes mellitus (DM), alcohol abuse, and cancer.Periodontitis may increase the risk of subsequent depression and was suggested an independent risk factor regardless of sex, age, and most comorbidities. However, DM, alcohol abuse, and cancer may prevent the development of subsequent depression because of DM treatment, the paradoxical effect of alcohol, and emotional distress to cancer, respectively. Prospective studies on the relationship between periodontitis and depression are warranted.


Assuntos
Transtorno Depressivo/epidemiologia , Periodontite/epidemiologia , Adulto , Idoso , Comorbidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco
11.
Cancer Cell ; 28(2): 240-52, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26267537

RESUMO

By integrating growth pathways on which cancer cells rely, steroid receptor coactivators (SRC-1, SRC-2, and SRC-3) represent emerging targets in cancer therapeutics. High-throughput screening for SRC small molecule inhibitors (SMIs) uncovered MCB-613 as a potent SRC small molecule "stimulator" (SMS). We demonstrate that MCB-613 can super-stimulate SRCs' transcriptional activity. Further investigation revealed that MCB-613 increases SRCs' interactions with other coactivators and markedly induces ER stress coupled to the generation of reactive oxygen species (ROS). Because cancer cells overexpress SRCs and rely on them for growth, we show that we can exploit MCB-613 to selectively induce excessive stress in cancer cells. This suggests that over-stimulating the SRC oncogenic program can be an effective strategy to kill cancer cells.


Assuntos
Neoplasias/prevenção & controle , Coativador 1 de Receptor Nuclear/metabolismo , Coativador 2 de Receptor Nuclear/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cicloexanonas/química , Cicloexanonas/metabolismo , Cicloexanonas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células HEK293 , Células HeLa , Humanos , Immunoblotting , Células MCF-7 , Estrutura Molecular , Mutação , Neoplasias/genética , Neoplasias/metabolismo , Coativador 1 de Receptor Nuclear/genética , Coativador 2 de Receptor Nuclear/genética , Coativador 3 de Receptor Nuclear/genética , Estresse Oxidativo/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Piridinas/química , Piridinas/metabolismo , Piridinas/farmacologia , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Mol Cell Endocrinol ; 372(1-2): 12-22, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23523566

RESUMO

Androgen receptor (AR) signaling plays a pivotal role in growth and survival of prostate cancer cells. c-Jun is an important member of the activator protein 1 (AP-1) family and was shown to interact with AR. However, the role of c-Jun in AR signaling remains controversial, with being a coactivator or a corepressor reported. Here, utilizing multiple approaches, we show that c-Jun efficiently inhibits AR activity and the growth of prostate cancer cells. Overexpression of c-Jun inhibits not only the activities of various androgen-responsive promoters but also the transcripts of multiple AR target genes. Interestingly, long-term c-Jun overexpression also down-regulates AR expression at both the protein and mRNA levels. Molecular analysis suggests that c-Jun inhibits AR transactivation potential via an unknown target gene. The inhibition of AR by c-Jun occurs in both hormone naïve and castration-resistant prostate cancer cells. Our results unravel a novel mechanism by which c-Jun antagonizes the AR signaling.


Assuntos
Proteínas Proto-Oncogênicas c-jun/fisiologia , Receptores Androgênicos/metabolismo , Transcrição Gênica , Animais , Células COS , Linhagem Celular Tumoral , Proliferação de Células , Chlorocebus aethiops , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Regiões Promotoras Genéticas , Neoplasias da Próstata , Receptores Androgênicos/genética , Transdução de Sinais , Ativação Transcricional
13.
J Biol Chem ; 287(11): 8621-32, 2012 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-22275354

RESUMO

Activating transcription factor 2 (ATF2) belongs to the basic leucine zipper family of transcription factors. ATF2 regulates target gene expression by binding to the cyclic AMP-response element as a homodimer or a heterodimer with c-Jun. Cytoplasmic localization of ATF2 was observed in melanoma, brain tissue from patients with Alzheimer disease, prostate cancer specimens, and ionizing radiation-treated prostate cancer cells, suggesting that alteration of ATF2 subcellular localization may be involved in the pathogenesis of these diseases. We previously demonstrated that ATF2 is a nucleocytoplasmic shuttling protein, and it contains two nuclear localization signals in the basic region and one nuclear export signal (NES) in the leucine zipper domain (named LZ-NES). In the present study, we demonstrate that a hydrophobic stretch in the N terminus, (1)MKFKLHV(7), also functions as an NES (termed N-NES) in a chromosome region maintenance 1 (CRM1)-dependent manner. Mutation of both N-NES and LZ-NES results in a predominant nuclear localization, whereas mutation of each individual NES only partially increases the nuclear localization. These results suggest that cytoplasmic localization of ATF2 requires function of at least one of the NESs. Further, mutation of N-NES enhances the transcriptional activity of ATF2, suggesting that the novel NES negatively regulates the transcriptional potential of ATF2. Thus, ATF2 subcellular localization is probably modulated by multiple mechanisms, and further understanding of the regulation of ATF2 subcellular localization under various pathological conditions will provide insight into the pathophysiological role of ATF2 in human diseases.


Assuntos
Fator 2 Ativador da Transcrição/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Sinais de Exportação Nuclear , Transcrição Gênica , Fator 2 Ativador da Transcrição/genética , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Células COS , Chlorocebus aethiops , Feminino , Humanos , Zíper de Leucina , Masculino , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Mutação , Proteínas de Neoplasias/genética , Proteínas do Tecido Nervoso/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Estrutura Terciária de Proteína , Transporte Proteico/genética
14.
Am J Pathol ; 173(2): 433-41, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18583320

RESUMO

Aberrant expression of the steroidogenic acute regulatory (StAR) protein in human endometriotic stromal cells plays an important role in the development of endometriosis. Prostaglandin E(2) (PGE(2)) is a potent inducer of StAR expression in these cells; however, the mechanisms responsible for the transcriptional regulation of StAR remain to be elucidated. Herein we report that PGE(2)-induced StAR expression is independent of the transcriptional suppressor DAX-1 but is regulated by the transcriptional activator cyclic adenosine 3',5'-monophosphate (cAMP) response element-binding protein (CREB). A promoter activity assay revealed that the cis-element needed for the binding of the CCAAT/enhancer-binding protein (C/EBP) was critical for PGE(2)-induced StAR expression. Electrophoretic mobility shift assay demonstrated that this region of the StAR promoter was bound by C/EBPalpha, C/EBPbeta, and CREB. Forced expression of either C/EBPalpha or C/EBPbeta alone was sufficient to up-regulate StAR promoter activity whereas PGE(2) was needed to induce StAR promoter activity in CREB-overexpressed cells. Results from a chromatin immunoprecipitation assay demonstrated that the binding of C/EBPbeta to the StAR promoter was increased whereas CREB binding was unchanged after PGE(2) treatment. Taken together, PGE(2)-induced StAR promoter activity appears to be regulated by CREB and C/EBPbeta in a cooperative manner in ectopic human endometriotic stromal cells, providing a molecular framework for the etiology of endometriosis.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/fisiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Dinoprostona/fisiologia , Endometriose/metabolismo , Fosfoproteínas/biossíntese , Sítios de Ligação , Células Cultivadas , Receptor Nuclear Órfão DAX-1 , Proteínas de Ligação a DNA/metabolismo , Endometriose/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Fosfoproteínas/genética , Regiões Promotoras Genéticas , Receptores do Ácido Retinoico/metabolismo , Proteínas Repressoras/metabolismo , Elementos de Resposta , Células Estromais/metabolismo
15.
Endocrinology ; 144(9): 3934-42, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12933667

RESUMO

Steroidogenic acute regulatory protein (StAR) regulates the first committed step in the biosynthesis of steroids, and thus aberrant expression of StAR in endometriotic implants plays a critical role in the etiology of endometriosis. However, the mechanism responsible for abnormal expression of StAR in ectopic endometriotic tissues remains unknown. In the present study, we demonstrate that prostaglandin (PG) E(2) stimulates StAR protein expression at the cellular and molecular levels. PGE(2) caused a rapid increase in StAR expression that involves activation of the EP2 receptor-coupled protein kinase A pathway. Activation of EP2 receptor-induced phosphorylation of ERK and cAMP response element binding protein (CREB). However, activation of ERK did not involve in CREB phosphorylation or concomitantly StAR expression. Phosphorylation of CREB induced by PGE(2) increased the recruitment of CREB binding protein and thus histone H3 acetylation. Chromatin immunoprecipitation experiments showed that acetylated histone H3 bound to the proximal region of the StAR promoter was increased after 30 min treatment with PGE(2), and this was mirrored by an increase in nascent StAR RNA transcription. Treatment with the histone deacetylase inhibitor, tricostatin A, enhanced PGE(2)-induced nascent StAR RNA transcription. We conclude that increased histone H3 acetylation involving the EP2 receptor, protein kinase A, CREB, and CREB binding protein is responsible for PGE(2)-induced StAR gene activation in endometriotic stromal cells. Our current report may provide new insights in understanding mechanism of abnormally local production of estrogen and the etiology of endometriosis.


Assuntos
Endométrio/metabolismo , Fosfoproteínas/metabolismo , Receptores de Prostaglandina E/metabolismo , Células Estromais/metabolismo , Acetilação , Fator 2 Ativador da Transcrição , Sequência de Bases , Células Cultivadas , Cromatina/fisiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Endométrio/citologia , Feminino , Expressão Gênica/fisiologia , Histonas/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Fosfoproteínas/genética , Fosforilação , Regiões Promotoras Genéticas/fisiologia , RNA Mensageiro/metabolismo , Receptores de Prostaglandina E/genética , Receptores de Prostaglandina E Subtipo EP2 , Transdução de Sinais/fisiologia , Fatores de Transcrição/metabolismo
16.
FEBS Lett ; 543(1-3): 140-3, 2003 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-12753921

RESUMO

We demonstrate the mechanism by which Cordyceps sinensis (CS) mycelium regulates Leydig cell steroidogenesis. Mouse Leydig cells were treated with forskolin, H89, phorbol 12-myristate 13-acetate, staurosporine, or steroidogenic enzyme precursors with or without 3 mg/ml CS; then testosterone production was determined. H89, but not phorbol 12-myristate 13-acetate or staurosporine, decreased CS-treated Leydig cell steroidogenesis. CS inhibited Leydig cell steroidogenesis by suppressing the activity of P450scc enzyme, but not 3beta-hydroxysteroid dehydrogenase, 17alpha-hydroxylase, 20alpha-hydroxylase, or 17beta-hydroxysteroid dehydrogenase enzymes. Thus, CS activated the cAMP-protein kinase A signal pathway, but not protein kinase C, and attenuated P45scc enzyme activity to reduce human chorionic gonadotropin-stimulated steroidogenesis in purified mouse Leydig cells.


Assuntos
Cordyceps/fisiologia , Células Intersticiais do Testículo/metabolismo , Sulfonamidas , Testosterona/biossíntese , Androstenodiona/metabolismo , Animais , Células Cultivadas , Colforsina/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Hidroxicolesteróis/farmacologia , Isoquinolinas/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Micélio/fisiologia , Progestinas/metabolismo , Proteína Quinase C/antagonistas & inibidores , Estaurosporina/farmacologia , Acetato de Tetradecanoilforbol/farmacologia
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