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1.
Carcinogenesis ; 35(12): 2740-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25280564

RESUMO

Incidence of esophageal adenocarcinoma (EA) in Western countries has increased markedly in recent decades. Although several risk factors have been identified for EA and its precursor, Barrett's esophagus (BE), including reflux, Caucasian race, male gender, obesity, and smoking, less is known about the role of inherited genetic variation. Frequent somatic mutations in the tumor suppressor genes CDKN2A and TP53 were recently reported in EA tumors, while somatic alterations at 9p (CDKN2A) and 17p (TP53) have been implicated as predictors of progression from BE to EA. Motivated by these findings, we used data from a genome-wide association study of 2515 EA cases and 3207 controls to analyze 37 germline single nucleotide polymorphisms at the CDKN2A and TP53 loci. Three CDKN2A polymorphisms were nominally associated (P < 0.05) with reduced risk of EA: rs2518720 C>T [intronic, odds ratio 0.90, P = 0.0121, q = 0.3059], rs3088440 G>A (3'UTR, odds ratio 0.84, P = 0.0186, q = 0.3059), and rs4074785 C>T (intronic, odds ratio 0.85, P = 0.0248, q = 0.3059). None of the TP53 single nucleotide polymorphisms reached nominal significance. Two of the CDKN2A variants identified were also associated with reduced risk of progression from BE to EA, when assessed in a prospective cohort of 408 BE patients: rs2518720 (hazard ratio 0.57, P = 0.0095, q = 0.0285) and rs3088440 (hazard ratio 0.34, P = 0.0368, q = 0.0552). In vitro functional studies of rs3088440, a single nucleotide polymorphism located in the seed sequence of a predicted miR-663b binding site, suggested a mechanism whereby the G>A substitution may attenuate miR-663b-mediated repression of the CDKN2A transcript. This study provides the first evidence that germline variation at the CDKN2A locus may influence EA susceptibility.


Assuntos
Adenocarcinoma/genética , Esôfago de Barrett/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Neoplasias Esofágicas/genética , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética , Proteína Supressora de Tumor p53/genética , Adenocarcinoma/patologia , Idoso , Esôfago de Barrett/patologia , Estudos de Casos e Controles , Progressão da Doença , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco
2.
Clin Gastroenterol Hepatol ; 12(10): 1667-76.e1, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24530603

RESUMO

BACKGROUND & AIMS: Risks for some cancers increase with height. We investigated the relationship between height and risk of esophageal adenocarcinoma (EAC) and its precursor, Barrett's esophagus (BE). METHODS: We analyzed epidemiologic and genome-wide genomic data from individuals of European ancestry in the Barrett's and Esophageal Adenocarcinoma Consortium, from 999 cases of EAC, 2061 cases of BE, and 2168 population controls. Multivariable logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI) for associations between height and risks of EAC and BE. We performed a Mendelian randomization analysis to estimate an unconfounded effect of height on EAC and BE using a genetic risk score derived from 243 genetic variants associated with height as an instrumental variable. RESULTS: Height was associated inversely with EAC (per 10-cm increase in height: OR, 0.70; 95% CI, 0.62-0.79 for men and OR, 0.57; 95% CI 0.40-0.80 for women) and BE (per 10-cm increase in height: OR, 0.69; 95% CI, 0.62-0.77 for men and OR, 0.61; 95% CI, 0.48-0.77 for women). The risk estimates were consistent across strata of age, education level, smoking, gastroesophageal reflux symptoms, body mass index, and weight. Mendelian randomization analysis yielded results quantitatively similar to those from the conventional epidemiologic analysis. CONCLUSIONS: Height is associated inversely with risks of EAC and BE. Results from the Mendelian randomization study showed that the inverse association observed did not result from confounding factors. Mechanistic studies of the effect of height on EAC and BE are warranted; height could have utility in clinical risk stratification.


Assuntos
Adenocarcinoma/epidemiologia , Estatura , Neoplasias Esofágicas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Fatores de Risco
3.
Qual Health Res ; 24(12): 1673-85, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25192766

RESUMO

Research on patients' experiences of wait time for scheduled surgery has centered predominantly on the relative tolerability of perceived wait time and impacts on quality of life. We explored patients' experiences of time while waiting for three types of surgery with varied wait times--hip or knee replacement, shoulder surgery, and cardiac surgery. Thirty-two patients were recruited by their surgeons. We asked participants about their perceptions of time while waiting in two separate interviews. Using interpretative phenomenological analysis (IPA), we discovered connections between participant suffering, meaningfulness of time, and agency over the waiting period and the lived duration of time experience. Our findings reveal that chronological duration is not necessarily the most relevant consideration in determining the quality of waiting experience. Those findings helped us create a conceptual framework for lived wait time. We suggest that clinicians and policy makers consider the complexity of wait time experience to enhance preoperative patient care.


Assuntos
Pacientes/psicologia , Procedimentos Cirúrgicos Operatórios , Tempo , Listas de Espera , Feminino , Humanos , Entrevistas como Assunto , Masculino , Qualidade de Vida , Estresse Psicológico
4.
Gastroenterology ; 142(3): 442-452.e5; quiz e22-3, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22108196

RESUMO

BACKGROUND & AIMS: Regular use of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) has been reported to reduce risks of esophageal adenocarcinoma (EAC) and esophagogastric junctional adenocarcinoma (EGJA). However, individual studies have been too small to accurately assess the effects of medication type, frequency, or duration of use. We performed a pooled analysis to investigate these associations. METHODS: We performed a pooled analysis of 6 population-based studies within the Barrett's and Esophageal Adenocarcinoma Consortium to evaluate the association between NSAID use and the risk of EAC and EGJA, using uniform exposure definitions. We collected information from 6 studies (5 case-control and 1 cohort), with a total of 1226 EAC and 1140 EGJA cases, on aspirin and/or NSAID use. Study-specific odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariate adjusted logistic regression models and then pooled using a random effects meta-analysis model. RESULTS: Compared with nonusers, individuals who have used NSAIDs had a statistically significant reduced risk of EAC (OR, 0.68; 95% CI, 0.56-0.83); they also appeared to have a reduced risk of EGJA (OR, 0.83; 95% CI, 0.66-1.03). Similar reductions in risk were observed among individuals who took aspirin or nonaspirin NSAIDs. The highest levels of frequency (daily or more frequently) and duration (≥10 years) of NSAID use were associated with an approximately 40% reduction in risk of EAC, with ORs of 0.56 (95% CI, 0.43-0.73; P(trend) < .001) and 0.63 (95% CI, 0.45-0.90; P(trend) = .04), respectively. CONCLUSIONS: Although reverse causation could, in part, explain the inverse association observed between NSAID use and EAC risk, our pooled analysis suggests a possible role for NSAIDs in prevention of adenocarcinomas of the esophagus and esophagogastric junction.


Assuntos
Adenocarcinoma/prevenção & controle , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticarcinógenos/uso terapêutico , Neoplasias Esofágicas/prevenção & controle , Junção Esofagogástrica/efeitos dos fármacos , Neoplasias Gástricas/prevenção & controle , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Canadá/epidemiologia , Estudos de Casos e Controles , Estudos de Coortes , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Medição de Risco , Fatores de Risco , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/patologia , Fatores de Tempo , Estados Unidos/epidemiologia , Adulto Jovem
5.
Gut ; 60(8): 1029-37, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21406386

RESUMO

BACKGROUND AND AIMS: Alcohol intake is a strong and well established risk factor for oesophageal squamous cell carcinoma (OSCC), but the association with oesophageal adenocarcinoma (OA) or adjacent tumours of the oesophagogastric junction (OGJA), remains unclear. Therefore, the association of alcohol intake with OSCC, OA, and OGJA was determined in nine case-control studies and two cohort studies of the Barrett's Esophagus and Esophageal Adenocarcinoma Consortium (BEACON). MATERIALS AND METHODS: Information was collected on alcohol intake, age, sex, education, body mass index, gastro-oesophageal reflux, and tobacco smoking from each study. Along with 10,854 controls, 1821 OA, and 1837 OGJA, seven studies also collected OSCC cases (n=1016). Study specific ORs and 95% CIs were calculated from multivariate adjusted logistic regression models for alcohol intake in categories compared to non-drinkers. Summary risk estimates were obtained by random effects models. Results No increase was observed in the risk of OA or OGJA for increasing levels of any of the alcohol intake measures examined. ORs for the highest frequency category (≥ 7 drinks per day) were 0.97 (95% CI 0.68 to 1.36) for OA and 0.77 (95% CI = 0.54 to 1.10) for OGJA. Suggestive findings linked moderate intake (eg, 0.5 to <1 drink per day) to decreased risk of OA (OR 0.63, 95% CI 0.41 to 0.99) and OGJA (OR 0.78, 95% CI 0.62 to 0.99). In contrast, alcohol intake was strongly associated with increased risk of OSCC (OR for ≥ 7 drinks per day 9.62, 95% CI 4.26 to 21.71). CONCLUSIONS: In contrast to OSCC, higher alcohol consumption was not associated with increased risk of either OA or OGJA. The apparent inverse association observed with moderate alcohol intake should be evaluated in future prospective studies.


Assuntos
Adenocarcinoma/etiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Neoplasias Esofágicas/etiologia , Medição de Risco/métodos , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Inquéritos e Questionários , Estados Unidos/epidemiologia , Adulto Jovem
6.
Mol Carcinog ; 50(5): 390-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21268128

RESUMO

This study examined the frequency of loss of imprinting (LOI) and expression of the insulin-like growth factor 2 (IGF2) gene, and their relationship to selected clinical and pathological factors, in a well defined series of 90 Chinese patients with gastric cancer (GC) and 90 matched patients (controls) diagnosed with nonmalignant conditions. Using peripheral blood and gastric tissue samples, polymerase chain reaction-based assays and restriction endonuclease (Apa I) digestion revealed 33 GC patients and 21 controls to be Apa I informative. LOI of IGF2 was positive in 48.5% (16/33) of primary GC tumor tissues, in 21.2% (7/33) of histologically normal adjacent gastric mucosa (AM) and in 12.1% (4/33) of distant gastric mucosa (DM), and in 15.2% (5/33) of peripheral blood lymphocytes (PBLs). The prevalence of IGF2 LOI in PBL was not statistically different between GC patients (5/33, 15.2%) and control subjects (2/21, 9.5%), P = 0.69. Although patients who were found to have LOI of IGF2 were more likely to have advanced stage gastric tumors (P = 0.04), no statistically significant differences in survival were found based on imprinting status. IGF2 LOI was associated with an increased expression of IGF2 level in both tumors (P < 0.01) and blood (P < 0.01). The results of this study implicate IGF2 LOI in the molecular pathogenesis of GC, most likely through increased IGF2 expression. Although the precise molecular mechanisms by which LOI of IGF2 increases GC risk require further study, LOI of IGF2 may be a potentially important clinical epigenetic marker to identify individuals at increased risk for gastric malignancy.


Assuntos
Regulação Neoplásica da Expressão Gênica , Impressão Genômica , Fator de Crescimento Insulin-Like II/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Feminino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Imuno-Histoquímica , Fator de Crescimento Insulin-Like II/metabolismo , Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/sangue , Neoplasias Gástricas/metabolismo
7.
Mol Carcinog ; 49(3): 211-4, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20025073

RESUMO

Recent studies have suggested an association between dietary folate, and related B-vitamins, and risk for cancer, potentially mediated by the p53 tumor suppressor gene. The aim of this study was to explore the effect of dietary folate and vitamin B(6) intake on p53 in the molecular pathogenesis of esophageal adenocarcinoma (EADC). For each participant, a structured questionnaire was used to obtain detailed sociodemographic and lifestyle risk factors, including diet, from which folate and vitamin B(6) intake were calculated. Risks for p53 mutations, p53 mutations at CpG sites, and p53 protein overexpression among EADC cases (n = 54) were calculated using logistic regression with dietary folate and vitamin B(6) intake as predictive variables, adjusting for age, gender, smoking, and alcohol consumption. No significant differences were found for patients with EADC who had p53 mutations (n = 21) compared with patients with wild-type p53 (n = 33) with respect to selected clinicopathologic variables (age, gender, tumor grade, stage, alcohol, or tobacco consumption) and dietary intake of folate or vitamin B(6). No statistically significant associations were seen between dietary folate and vitamin B(6) intake (highest vs. lowest quartiles) and p53 mutations, p53 mutations at CpG sites (n = 12), and p53 protein overexpression (n = 17). We conclude that dietary intake of folate and vitamin B(6) do not appear to have an effect on p53, suggesting alternative molecular mechanisms underlying esophageal adenocarcinogenesis.


Assuntos
Adenocarcinoma/genética , Dieta , Neoplasias Esofágicas/genética , Ácido Fólico/administração & dosagem , Mutação/genética , Proteína Supressora de Tumor p53/genética , Vitamina B 6/administração & dosagem , Adenocarcinoma/patologia , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Estudos de Casos e Controles , Ilhas de CpG/genética , Neoplasias Esofágicas/patologia , Refluxo Gastroesofágico/genética , Refluxo Gastroesofágico/patologia , Humanos , Técnicas Imunoenzimáticas , Regiões Promotoras Genéticas/genética , Inquéritos e Questionários , Proteína Supressora de Tumor p53/metabolismo
8.
Carcinogenesis ; 30(12): 2117-22, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19843644

RESUMO

To evaluate loss of imprinting (LOI) and expression of the IGF2 gene in matched esophageal normal and adenocarcinoma tissues, we studied a prospective cohort of 77 patients who underwent esophageal resection between 1998 and 2003. IGF2 imprinting status was determined by reverse transcription-polymerase chain reaction (PCR) following ApaI digestion, and quantitative PCR was used to evaluate IGF2 expression, which was correlated with clinicopathologic findings, disease-free and overall survival. In total, 32% (14/44) of informative tissues showed loss of IGF2 imprinting, with a strong correlation between the tumor and normal esophageal epithelia (Kappa = 0.89, P < 0.01). Normal epithelia with LOI had increased expression of IGF2 [median: 2.91, 95% confidence interval (CI): 0.93-5.06] compared with imprinted normal epithelia (median: 1.13, 95% CI: 0.85-1.39) (P = 0.03). In contrast, tumors with LOI had significantly reduced IGF2 expression (median: 1.87, 95% CI: 0.53-5.21) compared with normally imprinted tumors (median: 6.79, 95% CI: 3.39-15.89) (P = 0.016). Patients below the age of 65 years with normally imprinted tumors had significantly reduced 5 year disease-free survival (DFS) (24%) compared with patients whose tumors had LOI for IGF2 (55%) (P = 0.03). Cox regression analysis showed that IGF2 overexpression was associated with significantly reduced disease-free survival (P = 0.04). We conclude that in a subgroup of younger patients, loss of IGF2 imprinting was associated with improved outcome following esophageal resection. Expression of IGF2 in esophageal adenocarcinoma and normal esophageal epithelia depended on imprinting status and tissue type, suggesting novel molecular regulatory mechanisms in esophageal tumorigenesis.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Esofágicas/metabolismo , Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica , Regulação da Expressão Gênica , Impressão Genômica , Fator de Crescimento Insulin-Like II/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
9.
Mol Carcinog ; 48(11): 982-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19582762

RESUMO

The objective of this exploratory study was to evaluate the role of the insulin-like growth factor I receptor (IGF-IR) in esophageal adenocarcinoma (EADC). Using quantitative PCR, we studied IGF-IR mRNA expression in 52 well-characterized surgically resected EADC and matched histologically normal esophageal tissues, and examined IGF-IR expression levels in relation to clinicopathologic characteristics, body mass index (BMI), and the common IGF-IR polymorphism (G1013A), recently proposed to modify risk of obesity for EADC. Expression levels of IGF-IR mRNA were not significantly different between EADC and matched histologically normal esophageal epithelia. Although no significant associations were found between IGF-IR expression and BMI, tumor differentiation, stage or survival, when stratified by genotype, patients with the polymorphic A variant had significantly higher IGF-IR expression in EADC tissues compared with matched normal epithelia. These findings suggest that G1013A most likely modulates IGF-IR function, possibly by influencing gene transcription or mRNA stability, and represents a plausible mechanistic link underlying the association between obesity and esophageal malignancy.


Assuntos
Adenocarcinoma/genética , Neoplasias Esofágicas/genética , Expressão Gênica , Obesidade/genética , Receptor IGF Tipo 1/genética , Adenocarcinoma/patologia , Idoso , Sequência de Bases , Índice de Massa Corporal , Primers do DNA , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA Mensageiro/genética
10.
Mol Carcinog ; 48(10): 965-74, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19415720

RESUMO

Reflux of acidic gastric contents and bile acids into the lower esophagus has been identified to have a central role in esophageal malignancy and is reported to upregulate caudal-related homologue 2 (CDX2), a regulatory gene involved in embryonic development and axial patterning of the alimentary tract. The aim of this study was to characterize the expression of CDX2 in a well-defined series of human esophageal tissues, comprising reflux-induced esophagitis, premalignant Barrett esophagus (BE), and primary esophageal adenocarcinoma (EADC). To explore potential molecular regulatory mechanisms, we also studied the expression of beta-catenin, SOX9, and CDX2 promoter methylation in esophageal tissues, in addition to the effect of bile acids and nitric oxide (NO) on CDX2 expression in the normal human esophageal cell line Het1A. Relative to matched normal esophageal epithelia, CDX2 was overexpressed in esophagitis (37% for RNA; cytoplasmic immunoreactivity in 48% of tissues), a high proportion (91%) of BE tissues, and in EADC (57% for RNA; cell nuclear immunopositivity in 80%). An association with beta-catenin expression was seen, but not with SOX9 or CDX2 promoter methylation. In Het1A cells, CDX2 was upregulated following exposure to bile acids and NO, alone and in combination. These results further implicate CDX2 and beta-catenin in the molecular pathogenesis of human EADC. The observed synergistic effect of NO on the efficacy of bile acid-induction of CDX2 suggests a novel role for NO in modulating the development of the Barrett phenotype and esophageal adenocarcinogenesis.


Assuntos
Adenocarcinoma/genética , Esôfago de Barrett/genética , Neoplasias Esofágicas/genética , Esofagite/genética , Proteínas de Homeodomínio/genética , RNA Mensageiro/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica , Esôfago de Barrett/metabolismo , Esôfago de Barrett/patologia , Ácidos e Sais Biliares/farmacologia , Western Blotting , Fator de Transcrição CDX2 , Células Cultivadas , Metilação de DNA/efeitos dos fármacos , Sinergismo Farmacológico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Esofagite/metabolismo , Esofagite/patologia , Esôfago/efeitos dos fármacos , Esôfago/metabolismo , Sequestradores de Radicais Livres/farmacologia , Fármacos Gastrointestinais/farmacologia , Proteínas de Homeodomínio/metabolismo , Humanos , Técnicas Imunoenzimáticas , Óxido Nítrico/farmacologia , Regiões Promotoras Genéticas/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
11.
Analyst ; 134(6): 1240-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19475154

RESUMO

The objective of this exploratory study was to evaluate the feasibility of using Fourier-Transform Infrared (FTIR) spectromicroscopy to characterize formalin-fixed, paraffin-embedded human esophageal tissues. Matched histologically normal esophageal squamous epithelium (NS), premalignant Barrett esophagus (BE), and primary esophageal adenocarcinoma (EADC) tissues, each defined according to strict clinicopathologic criteria, were obtained from patients who underwent esophageal resection. Using confocal IR microscopy, measurements in the mid-IR spectral region were carried out in transflection configuration, scanning regions of interest in 15 microm steps. A multidimensional dataset reporting the spectroscopic properties at each sampled point were analyzed by performing a hierarchical cluster analysis on the second derivative of spectral traces. Normal esophageal epithelia were characterized by a few well defined regions, mostly of large size (tens of contiguous pixels), which correlated with tissue histology, specifically the basal cell layer. BE tissues had characteristic regions localized to gland crypts, ranging in size from one pixel to a few tens of pixels, which displayed IR spectra with defined absorption features characteristic of glycoproteins. The incorporation of synchrotron light to improve the resolution of individual cells in BE tissues has demonstrated that these glycoproteins are associated with goblet cells, the characteristic cell type defining BE. Whereas the highly fragmented regions identified in EADC likely reflect tumor heterogeneity, FTIR mapping would appear to be a potentially useful technique to identify premalignant BE tissues. The technical feasibility of using FTIR to characterize formalin-fixed, paraffin-embedded human esophageal tissues demonstrates the potential of this technique to study archival human BE tissue specimens via automated screening techniques.


Assuntos
Esôfago de Barrett/patologia , Neoplasias Esofágicas/patologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Adenocarcinoma/patologia , Análise por Conglomerados , Células Caliciformes/citologia , Células Caliciformes/patologia , Humanos , Intestinos/patologia , Luz , Metaplasia/patologia , Microscopia , Síncrotrons
12.
Future Oncol ; 5(7): 1051-63, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19792973

RESUMO

Over the past three decades, an increasing incidence of esophageal adenocarcinoma (EADC) has been reported throughout North America and Europe at a rate exceeding that of any other human solid tumor. Recent studies have clearly implicated chronic gastroesophageal reflux disease and several lifestyle risk factors, including tobacco consumption, diet and obesity, to be associated with increased risk of EADC. Although physical inactivity is now recognized as a risk factor for several chronic diseases including cancer, only a very limited number of studies have specifically evaluated the association between physical activity and esophageal malignancy. Furthermore, the precise biological mechanisms underlying the association between physical activity, obesity and cancer risk remain unclear. Since successful promotion of healthy body weight and exercise may substantially reduce the future incidence of cancer in the population, the purpose of this review is to explore current evidence linking physical activity, obesity and risk of malignancy - specifically EADC.


Assuntos
Adenocarcinoma/etiologia , Neoplasias Esofágicas/etiologia , Exercício Físico , Obesidade , Adenocarcinoma/epidemiologia , Neoplasias Esofágicas/epidemiologia , Humanos , Fatores de Risco
13.
BMC Mol Biol ; 9: 10, 2008 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-18215310

RESUMO

BACKGROUND: GFG/NUDT is a nudix hydrolase originally identified as the product of the fibroblast growth factor-2 antisense (FGF-AS) gene. While the FGF-AS RNA has been implicated as an antisense regulator of FGF-2 expression, the expression and function of the encoded GFG protein is largely unknown. Alternative splicing of the primary FGF-AS mRNA transcript predicts multiple GFG isoforms in many species including rat. In the present study we focused on elucidating the expression and subcellular distribution of alternatively spliced rat GFG isoforms. RESULTS: RT-PCR and immunohistochemistry revealed tissue-specific GFG mRNA isoform expression and subcellular distribution of GFG immunoreactivity in cytoplasm and nuclei of a wide range of normal rat tissues. FGF-2 and GFG immunoreactivity were co-localized in some, but not all, tissues examined. Computational analysis identified a mitochondrial targeting sequence (MTS) in the N-terminus of three previously described rGFG isoforms. Confocal laser scanning microscopy and subcellular fractionation analysis revealed that all rGFG isoforms bearing the MTS were specifically targeted to mitochondria whereas isoforms and deletion mutants lacking the MTS were localized in the cytoplasm and nucleus. Mutation and deletion analysis confirmed that the predicted MTS was necessary and sufficient for mitochondrial compartmentalization. CONCLUSION: Previous findings strongly support a role for the FGF antisense RNA as a regulator of FGF2 expression. The present study demonstrates that the antisense RNA itself is translated, and that protein isoforms resulting form alternative RNA splicing are sorted to different subcellular compartments. FGF-2 and its antisense protein are co-expressed in many tissues and in some cases in the same cells. The strong conservation of sequence and genomic organization across animal species suggests important functional significance to the physical association of these transcript pairs.


Assuntos
Processamento Alternativo/genética , Fatores de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica , RNA Antissenso/genética , Animais , Primers do DNA/genética , Imuno-Histoquímica , Microscopia Confocal , Mitocôndrias/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Mol Carcinog ; 47(4): 275-85, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17849424

RESUMO

Nitric oxide (NO) has been implicated as a potential causative factor for endogenous p53 mutations in gastrointestinal malignancy. To investigate the role of NO in esophageal adenocarcinoma (EADC), we studied patterns of p53 mutations, expression of inducible nitric oxide synthase (iNOS) and the tissue accumulation of nitrotyrosine (NTS), a stable reaction product of NO and a marker for cellular protein damage, in human premalignant and malignant esophageal epithelia. Tissues were obtained from patients with gastroesophageal reflux disease (GERD)-induced esophagitis (n = 76), Barrett's esophagus (BE; n = 119) and primary EADC (n = 54). DNA sequencing was used to characterize p53 mutations, RT-PCR to study iNOS mRNA expression, and immunohistochemistry to study NTS. Relative to self-matched normal epithelia, a progressive increase in iNOS mRNA expression was seen in GERD (30%; 23/76), BE (48%; 57/119), and EADC (63%; 34/54) tissues (P < 0.001). Among patients with EADC, elevated levels of NTS immunoreactivity were more frequent in tumors with p53 mutations (11/21; 52%) compared with tumors with wild-type p53 (9/33; 27%; P = 0.063), and specifically in tumors with p53 mutations at CpG dinucleotides (10/12; 83%) compared with non-CpG p53 mutations (1/9; 11%; P = 0.008). The increasing frequency of iNOS (mRNA) overexpression in GERD, BE and EADC supports the hypothesis that an active inflammatory process, most likely a consequence of GERD, underlies molecular progression to EADC. The highly significant association between NTS, reflecting chronic NO-induced cellular protein damage, and endogenous p53 mutations at CpG dinucleotides, provides further evidence for a molecular link between chronic inflammation and esophageal malignancy.


Assuntos
Adenocarcinoma/enzimologia , Esôfago de Barrett/enzimologia , Neoplasias Esofágicas/enzimologia , Genes p53 , Óxido Nítrico Sintase Tipo II/fisiologia , Proteína Supressora de Tumor p53/genética , Tirosina/análogos & derivados , Adenocarcinoma/etiologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/etiologia , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Doença Crônica , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Feminino , Humanos , Mediadores da Inflamação/fisiologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/biossíntese , Mutação Puntual , Tirosina/fisiologia
15.
J Mol Med (Berl) ; 85(11): 1215-28, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17569023

RESUMO

Overexpression of FGF-2 is associated with tumor recurrence and reduced survival after surgical resection of esophageal cancer, and these risks are reduced in tumors co-expressing the FGF antisense (FGF-AS) RNA. The aim of this study was to characterize the expression of alternatively spliced FGF-AS transcripts and encoded nudix-motif proteins in normal human tissues and in esophageal adenocarcinoma, and to correlate their expression with clinicopathologic findings and outcome. Three alternatively spliced FGF-AS transcripts encoding GFG/NUDT6 isoforms with distinct N termini were detected in various human tissues including esophageal adenocarcinoma. Expression of each isoform as a fusion protein with enhanced green fluorescent protein revealed differential subcellular trafficking: hGFGa is localized to mitochondria by an N-terminal targeting sequence (MTS), whereas hGFGb and hGFGc were localized in the cytoplasm and nucleus. Mutation/deletion analysis confirmed that the predicted MTS was necessary and sufficient for mitochondrial compartmentalization. The predominant FGF-AS mRNA expressed in esophageal tumors was splice variant b. GFG immunoreactivity was detected in the cytoplasm of all esophageal adenocarcinomas and in 88% of tumor cell nuclei. Although we found a trend towards reduced disease-free survival in patients with FGF-2 overexpressing esophageal adenocarcinomas, significantly worse disease-free survival was noted among patients whose tumors did not also overexpress the FGF-AS b isoform (p = 0.03). Tetracycline-inducible FGF-AS b expression in stably transfected human Seg-1 esophageal adenocarcinoma cells resulted in a significant suppression of steady state FGF-2 mRNA content and cell proliferation. Our data implicate the FGF-AS b isoform in modulation of FGF-2 expression and clinical outcome in esophageal adenocarcinoma.


Assuntos
Adenocarcinoma/genética , Processamento Alternativo/genética , Neoplasias Esofágicas/genética , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Transporte de RNA , Adenocarcinoma/patologia , Sequência de Aminoácidos , Animais , Células COS , Proliferação de Células , Chlorocebus aethiops , Biologia Computacional , Intervalo Livre de Doença , Neoplasias Esofágicas/patologia , Fator 2 de Crescimento de Fibroblastos/química , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Teste de Complementação Genética , Humanos , Dados de Sequência Molecular , Filogenia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Deleção de Sequência , Frações Subcelulares/metabolismo
16.
Mol Carcinog ; 46(12): 971-80, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17477358

RESUMO

Inhibition of cyclooxygenase (COX)-2 is reported to suppress growth and induce apoptosis in human esophageal adenocarcinoma (EADC) cells, although the precise biologic mechanism is unclear. In this study we tested the hypothesis that the antitumor activity of COX-2 inhibitors may involve modulation of basic fibroblast growth factor (FGF-2), which is overexpressed in EADC. We evaluated the effects of NS-398, a selective COX-2 inhibitor, on FGF-2 expression and proliferation of EADC cell lines that express COX-2 and those that do not. We also correlated COX-2 and FGF-2 expression with clinico-pathologic findings and outcome in a well-characterized series of surgically resected EADC tissues. Seg-1 cells robustly expressed COX-2 and FGF-2, whereas Bic-1 cells expressed neither transcript. FGF-2 was reduced to undetectable levels in Seg-1 cells following NS-398 treatment, but increased within 4 h of drug removal. NS-398 significantly inhibited the growth of Seg-1 cells, and this effect was ameliorated by addition of exogenous FGF-2. In contrast, NS-398 had no effect on Bic-1 cell proliferation and FGF-2 alone had no effect on proliferation of either cell line. NS-398, or a neutralizing anti-FGF-2 antibody, induced apoptosis in Seg-1 cells, and these effects were inhibited by addition of exogenous FGF-2. COX-2 protein was strongly expressed in 46% (10/22) of EADCs, and was associated with a trend towards reduced disease-free survival. These findings indicate that the antitumor effects of COX-2 inhibition in EADC cells may be mediated via suppression of FGF-2, and that COX-2 may be a clinically relevant molecular marker in the management of human EADC.


Assuntos
Adenocarcinoma/enzimologia , Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase/farmacologia , Neoplasias Esofágicas/enzimologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Nitrobenzenos/farmacologia , Sulfonamidas/farmacologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Idoso , Apoptose , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/biossíntese , Ciclo-Oxigenase 2/genética , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/patologia , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Imunofluorescência , Humanos , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas/efeitos dos fármacos
17.
J Health Psychol ; 22(3): 290-301, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-26349617

RESUMO

The aim of this study was to understand experiences of wait time among patients awaiting scheduled orthopaedic or cardiac surgery. Using a qualitative approach, 32 patients completed two interviews each regarding their wait time experiences, including effects of waiting. Patient experiences of wait time varied regardless of actual wait time and included reports of restriction, uncertainty, resignation, coping and opportunity. Participants' waiting experiences indicate a complex relationship between greater symptom severity and less tolerance for wait time. We suggest healthcare resources focus on alleviating the deleterious effects of waiting for certain patients rather than reducing absolute wait times.


Assuntos
Procedimentos Cirúrgicos Cardíacos/psicologia , Procedimentos Ortopédicos/psicologia , Período Pré-Operatório , Listas de Espera , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Fatores de Tempo
18.
Clin Cancer Res ; 11(21): 7683-91, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16278388

RESUMO

PURPOSE: The basic fibroblast growth factor (FGF-2) gene is bidirectionally transcribed to generate overlapping sense and antisense (FGF-AS) mRNAs. FGF-AS has been implicated in the post-transcriptional regulation of FGF-2 expression. The aim of this study was to characterize FGF-2 and FGF-AS in esophageal cancer and to correlate their expression with clinicopathologic findings and outcome. EXPERIMENTAL DESIGN: Reverse transcription-PCR was used to study FGF-2 and FGF-AS mRNA expression (normalized to glyceraldehyde-3-phosphate dehydrogenase) in 48 esophageal cancers relative to matched histologically normal esophageal epithelia (internal control). We used Cox proportional hazards analysis to calculate hazard ratios for recurrence and survival of patients with underexpression relative to the overexpression of FGF-2 and/or FGF-AS. RESULTS: Overexpression of FGF-2 mRNA, by comparison with tumors underexpressing FGF-2, was associated with significantly increased risk for tumor recurrence (hazard ratio, 3.80; 95% confidence interval, 1.64-8.76) and reduced overall survival (hazard ratio, 2.11; 95% confidence interval, 1.0-4.58). When the effects of FGF-2 and FGF-AS were considered simultaneously, the association of FGF-2 mRNA overexpression with recurrence and mortality was even more pronounced, whereas FGF-AS mRNA overexpression was associated with reduced risk for recurrence and improved survival. CONCLUSIONS: Overexpression of FGF-2 mRNA is associated with tumor recurrence and reduced survival after surgical resection of esophageal cancer and that these risks are reduced in tumors coexpressing the FGF-AS mRNA. These data support the hypothesis that FGF-AS is a novel tumor suppressor that modulates the effect of FGF-2 expression and may have potential clinical application to the development of novel therapeutic strategies.


Assuntos
Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Fator 2 de Crescimento de Fibroblastos/biossíntese , Fator 2 de Crescimento de Fibroblastos/genética , Regulação Neoplásica da Expressão Gênica , Oligonucleotídeos Antissenso/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular , Linhagem Celular Tumoral , Intervalo Livre de Doença , Neoplasias Esofágicas/mortalidade , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Microscopia Confocal , Microscopia de Fluorescência , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Processamento Pós-Transcricional do RNA , RNA Mensageiro/metabolismo , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
19.
Can Respir J ; 13(4): 215-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16779467

RESUMO

Burkholderia cepacia is an important opportunistic pathogen among patients with cystic fibrosis (CF); it is associated with deterioration of lung function, poor outcome following lung transplantation and increased mortality. Fever, an elevated white blood cell count, weight loss and an often fatal deterioration in pulmonary function characterize a particular clinical course, termed "Cepacia syndrome". The present case report describes a 40-year-old man with CF who developed Cepacia syndrome complicated by suppurative mediastinitis, from which B cepacia was isolated. Despite optimal medical and surgical therapy, this patient succumbed to his illness. Those caring for patients with CF should be aware of this potentially catastrophic complication of B cepacia infection, especially in the setting of Cepacia syndrome.


Assuntos
Infecções por Burkholderia/complicações , Burkholderia cepacia/isolamento & purificação , Fibrose Cística/complicações , Mediastinite/complicações , Adulto , Infecções por Burkholderia/diagnóstico por imagem , Infecções por Burkholderia/microbiologia , Fibrose Cística/diagnóstico por imagem , Humanos , Masculino , Mediastinite/diagnóstico por imagem , Radiografia
20.
Cancer Lett ; 217(2): 221-30, 2005 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-15617840

RESUMO

Alteration of the p16 tumor suppressor gene has been implicated as a critical lesion in the molecular pathogenesis of esophageal adenocarcinoma. The aim of this study was to characterize the spectrum of p16 alterations in surgically resected esophageal tissues, comprising histologically normal esophageal squamous and gastric epithelia, premalignant Barrett's epithelia, and associated esophageal adenocarcinomas, and to explore associations between p16 mRNA expression and p16 mutations, deletions, promoter hypermethylation, p16 protein expression, and clinico-pathologic features for the same tissues. We have shown that while p16 mutations are uncommon (2%; 1/54), hypermethylation of the p16 promoter is detected in 43% (9/21) of histologically normal epithelia, in 77% (14/18) of associated Barrett's epithelia, and in 85% (18/21) of esophageal adenocarcinomas. However, p16 mRNA levels (relative to matched normal epithelia) were variable in Barrett's epithelia and adenocarcinomas, having no clear correlation with methylation status or other molecular and clinico-pathological parameters. These findings are consistent with a role for the p16 tumor suppressor gene early in the molecular progression of Barrett's epithelium to invasive esophageal adenocarcinoma, but do not support the notion that the detection of hypermethylation is systematically associated with low levels of expression.


Assuntos
Adenocarcinoma/genética , Esôfago de Barrett/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Neoplasias Esofágicas/genética , Adenocarcinoma/metabolismo , Esôfago de Barrett/metabolismo , Metilação de DNA , Epigênese Genética , Neoplasias Esofágicas/metabolismo , Humanos , Imuno-Histoquímica , Regiões Promotoras Genéticas/genética , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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