RESUMO
Lung cancer is the most common cause of cancer death worldwide, with over one million cases annually. To identify genetic factors that modify disease risk, we conducted a genome-wide association study by analysing 317,139 single-nucleotide polymorphisms in 1,989 lung cancer cases and 2,625 controls from six central European countries. We identified a locus in chromosome region 15q25 that was strongly associated with lung cancer (P = 9 x 10(-10)). This locus was replicated in five separate lung cancer studies comprising an additional 2,513 lung cancer cases and 4,752 controls (P = 5 x 10(-20) overall), and it was found to account for 14% (attributable risk) of lung cancer cases. Statistically similar risks were observed irrespective of smoking status or propensity to smoke tobacco. The association region contains several genes, including three that encode nicotinic acetylcholine receptor subunits (CHRNA5, CHRNA3 and CHRNB4). Such subunits are expressed in neurons and other tissues, in particular alveolar epithelial cells, pulmonary neuroendocrine cells and lung cancer cell lines, and they bind to N'-nitrosonornicotine and potential lung carcinogens. A non-synonymous variant of CHRNA5 that induces an amino acid substitution (D398N) at a highly conserved site in the second intracellular loop of the protein is among the markers with the strongest disease associations. Our results provide compelling evidence of a locus at 15q25 predisposing to lung cancer, and reinforce interest in nicotinic acetylcholine receptors as potential disease candidates and chemopreventative targets.
Assuntos
Cromossomos Humanos Par 15/genética , Predisposição Genética para Doença/genética , Neoplasias Pulmonares/genética , Subunidades Proteicas/genética , Receptores Nicotínicos/genética , Europa (Continente) , Genótipo , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
There is extensive evidence that increases in blood and tissue concentrations of steroid hormones and of insulin-like growth factor I (IGF-I) are associated with breast cancer risk. However, studies of common variation in genes involved in steroid hormone and IGF-I metabolism have yet to provide convincing evidence that such variants predict breast cancer risk. The Breast and Prostate Cancer Cohort Consortium (BPC3) is a collaboration of large US and European cohorts. We genotyped 1416 tagging single nucleotide polymorphisms (SNPs) in 37 steroid hormone metabolism genes and 24 IGF-I pathway genes in 6292 cases of breast cancer and 8135 controls, mostly Caucasian, postmenopausal women from the BPC3. We also imputed 3921 additional SNPs in the regions of interest. None of the SNPs tested was significantly associated with breast cancer risk, after correction for multiple comparisons. The results remained null when cases and controls were stratified by age at diagnosis/recruitment, advanced or nonadvanced disease, body mass index, with or without in situ cases; or restricted to Caucasians. Among 770 estrogen receptor-negative cases, an SNP located 3' of growth hormone receptor (GHR) was marginally associated with increased risk after correction for multiple testing (P(trend) = 1.5 × 10(-4)). We found no significant overall associations between breast cancer and common germline variation in 61 genes involved in steroid hormone and IGF-I metabolism in this large, comprehensive study. Although previous studies have shown that variations in these genes can influence endogenous hormone levels, the magnitude of the effect of single SNPs does not appear to be sufficient to alter breast cancer risk.
Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Hormônios Esteroides Gonadais/genética , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Próstata/genética , Idoso , Estudos de Coortes , Feminino , Hormônios Esteroides Gonadais/metabolismo , Haplótipos/genética , Humanos , Masculino , Pessoa de Meia-Idade , National Cancer Institute (U.S.) , Controle de Qualidade , Fatores de Risco , Estados UnidosRESUMO
Menopausal hormone therapy (MHT) is characterized by use of different constituents, regimens and routes of administration. We investigated the association between the use of different types of MHT and breast cancer risk in the EPIC cohort study. The analysis is based on data from 133,744 postmenopausal women. Approximately 133,744 postmenopausal women contributed to this analysis. Information on MHT was derived from country-specific self-administered questionnaires with a single baseline assessment. Incident breast cancers were identified through population cancer registries or by active follow-up (mean: 8.6 yr). Overall relative risks (RR) and 95% confidence interval (CI) were derived from country-specific Cox proportional hazard models estimates. A total of 4312 primary breast cancers were diagnosed during 1,153,747 person-years of follow-up. Compared with MHT never users, breast cancer risk was higher among current users of estrogen only (RR: 1.42, 95% CI 1.23-1.64) and higher still among current users of combined MHT (RR: 1.77, 95% CI 1.40-2.24; p = 0.02 for combined vs. estrogen-only). Continuous combined regimens conferred a 43% (95% CI: 19-72%) greater risk compared with sequential regimens. There was no significant difference between progesterone and testosterone derivatives in sequential regimens. There was no significant variation in risk linked to the estrogenic component of MHT, neither for oral vs. cutaneous administration nor for estradiol compounds vs. conjugated equine estrogens. Estrogen-only and combined MHT uses were associated with increased breast cancer risk. Continuous combined preparations were associated with the highest risk. Further studies are needed to disentangle the effects of the regimen and the progestin component.
Assuntos
Neoplasias da Mama/epidemiologia , Terapia de Reposição de Estrogênios/métodos , Sistema de Registros/estatística & dados numéricos , Inquéritos e Questionários , Idoso , Neoplasias da Mama/etiologia , Dinamarca/epidemiologia , Terapia de Reposição de Estrogênios/efeitos adversos , Europa (Continente)/epidemiologia , Seguimentos , França/epidemiologia , Alemanha/epidemiologia , Grécia/epidemiologia , Humanos , Itália/epidemiologia , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Noruega/epidemiologia , Pós-Menopausa , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Espanha/epidemiologia , Suécia/epidemiologia , Reino Unido/epidemiologiaRESUMO
The food frequency questionnaire approach to dietary assessment is ubiquitous in nutritional epidemiology research. Food records and recalls provide approaches that may also be adaptable for use in large epidemiologic cohorts, if warranted by better measurement properties. The authors collected (2007-2009) a 4-day food record, three 24-hour dietary recalls, and a food frequency questionnaire from 450 postmenopausal women in the Women's Health Initiative prospective cohort study (enrollment, 1994-1998), along with biomarkers of energy and protein consumption. Through comparison with biomarkers, the food record is shown to provide a stronger estimate of energy and protein than does the food frequency questionnaire, with 24-hour recalls mostly intermediate. Differences were smaller and nonsignificant for protein density. Food frequencies, records, and recalls were, respectively, able to "explain" 3.8%, 7.8%, and 2.8% of biomarker variation for energy; 8.4%, 22.6%, and 16.2% of biomarker variation for protein; and 6.5%, 11.0%, and 7.0% of biomarker variation for protein density. However, calibration equations that include body mass index, age, and ethnicity substantially improve these numbers to 41.7%, 44.7%, and 42.1% for energy; 20.3%, 32.7%, and 28.4% for protein; and 8.7%, 14.4%, and 10.4% for protein density. Calibration equations using any of the assessment procedures may yield suitable consumption estimates for epidemiologic study purposes.
Assuntos
Registros de Dieta , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Rememoração Mental , Idoso , Biomarcadores/urina , Índice de Massa Corporal , Deutério , Metabolismo Energético , Feminino , Humanos , Pessoa de Meia-Idade , Isótopos de Oxigênio , Inquéritos e Questionários , UrináliseRESUMO
Recently, the rs6232 (N221D) and rs6235 (S690T) SNPs in the PCSK1 gene were associated with obesity in a meta-analysis comprising more than 13 000 individuals of European ancestry. Each additional minor allele of rs6232 or rs6235 was associated with a 1.34- or 1.22-fold increase in the risk of obesity, respectively. So far, only one relatively small study has aimed to replicate these findings, but could not confirm the association of the rs6235 SNP and did not study the rs6232 variant. In the present study, we examined the associations of the rs6232 and rs6235 SNPs with obesity in a population-based cohort consisting of 20 249 individuals of European descent from Norfolk, UK. Logistic regression and generalized linear models were used to test the associations of the risk alleles with obesity and related quantitative traits, respectively. Neither of the SNPs was significantly associated with obesity, BMI or waist circumference under the additive genetic model (P > 0.05). However, we observed an interaction between rs6232 and age on the level of BMI (P = 0.010) and risk of obesity (P = 0.020). The rs6232 SNP was associated with BMI (P = 0.021) and obesity (P = 0.022) in the younger individuals [less than median age (59 years)], but not among the older age group (P = 0.81 and P = 0.68 for BMI and obesity, respectively). In conclusion, our data suggest that the PCSK1 rs6232 and rs6235 SNPs are not major contributors to common obesity in the general population. However, the effect of rs6232 may be age-dependent.
Assuntos
Neuropeptídeos/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Reino UnidoRESUMO
We have conducted a three-stage, comprehensive single nucleotide polymorphism (SNP)-tagging association study of ESR1 gene variants (SNPs) in more than 55,000 breast cancer cases and controls from studies within the Breast Cancer Association Consortium (BCAC). No large risks or highly significant associations were revealed. SNP rs3020314, tagging a region of ESR1 intron 4, is associated with an increase in breast cancer susceptibility with a dominant mode of action in European populations. Carriers of the c-allele have an odds ratio (OR) of 1.05 [95% Confidence Intervals (CI) 1.02-1.09] relative to t-allele homozygotes, P = 0.004. There is significant heterogeneity between studies, P = 0.002. The increased risk appears largely confined to oestrogen receptor-positive tumour risk. The region tagged by SNP rs3020314 contains sequence that is more highly conserved across mammalian species than the rest of intron 4, and it may subtly alter the ratio of two mRNA splice forms.
Assuntos
Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Mama/patologia , Feminino , Haplótipos , Humanos , Estadiamento de Neoplasias , RNA Neoplásico/genéticaRESUMO
Elaidic acid is the main unnatural trans fatty acid isomer occurring during partial hydrogenation of vegetable oils used as ingredients for the formulation of processed foods. The main objective is to assess associations between processed food intakes and plasma phospholipid elaidic acid concentrations within the European Prospective Investigation into Cancer and Nutrition study. A cross-sectional study was used to determine fatty acid profiles in 3,003 subjects from 16 centers. Single 24-h dietary recalls (24-HDR) were collected using a standardized computerized interview program. Food intakes were computed according to their degree of processing (moderately/nonprocessed foods, processed staple foods, highly processed foods). Adjusted ecological and individual correlations were calculated between processed food intakes and plasma elaidic acid levels. At the population level, mean intakes of highly processed foods were strongly correlated with mean levels of plasma elaidic acid in men (P = 0.0016) and in women (P = 0.0012). At the individual level, these associations remained but at a much lower level in men (r = 0.08, P = 0.006) and in women (r = 0.09, P = 0.0001). The use of an averaged 24-HDR measure of highly processed food intakes is adequate for predicting mean levels of plasma elaidic acid among European populations.
Assuntos
Ingestão de Energia , Fast Foods , Comportamento Alimentar , Ácido Oleico/sangue , Fosfolipídeos/sangue , Estudos de Coortes , Estudos Transversais , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/sangue , Europa (Continente) , Ácidos Graxos/administração & dosagem , Ácidos Graxos/sangue , Feminino , Manipulação de Alimentos/métodos , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias/patologia , Inquéritos Nutricionais , Ácidos Oleicos , Inquéritos e QuestionáriosRESUMO
OBJECTIVES: Evidence suggests that certain occupations and related exposures may increase the risk of malignant lymphoma. Farming, printing and paper industry, wood processing, meat handling and processing, welding, shoe and leather manufacturing and teaching profession are among the categories that have been implicated in previous studies. The relationship between occupation and malignant lymphoma has been investigated in a large European prospective study. METHODS: We investigated occupational risks for lymphomas in the European Prospective Investigation into Cancer and Nutrition (EPIC). The mean follow-up time for 348,555 subjects was 9 years (SD: 2 years). The analysis was based on 866 and 48 newly diagnosed cases of non-Hodgkin's lymphoma (NHL) and Hodgkin's lymphoma (HL). These were identified in the EPIC subcohorts with occupational data. Data on 52 occupations were collected through standardised questionnaires. Cox proportional hazard models were used to explore the association between occupation and risk of malignant lymphoma. RESULTS: The following occupations were positively associated with malignant NHL after adjustment for study centre, age, sex, socioeconomic status (SES), smoking and alcohol: butchers (HR=1.53, 95% CI 1.05 to 2.48, including multiple myeloma/plasmacytoma; HR=1.30, 95% CI 1.00 to 2.66, excluding multiple myeloma/plasmacytoma) and car repair workers (HR=1.50, 95% CI 1.01 to 2.00, including multiple myeloma/plasmacytoma; HR=1.51, 95% CI 1.01 to 2.31, excluding multiple myeloma/plasmacytoma). HL was associated with gasoline station occupation (HR=4.59, 95% CI 1.08 to 19.6). CONCLUSION: The findings in this current study of a higher risk of NHL among car repair workers and butchers and a higher risk of HL among gasoline station workers suggest a possible role from occupationally related exposures, such as solvents and zoonotic viruses, as risk factors for malignant lymphoma.
Assuntos
Linfoma/etiologia , Doenças Profissionais/etiologia , Adulto , Distribuição por Idade , Idoso , Métodos Epidemiológicos , Europa (Continente)/epidemiologia , Feminino , Humanos , Linfoma/epidemiologia , Linfoma não Hodgkin/epidemiologia , Linfoma não Hodgkin/etiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Ocupações/estatística & dados numéricosRESUMO
We followed-up for mortality and cancer incidence 1088 healthy non-smokers from a population-based study, who were characterized for 22 variants in 16 genes involved in DNA repair pathways. Follow-up was 100% complete. The association between polymorphism and mortality or cancer incidence was analyzed using Cox Proportional Hazard regression models. Ninety-five subjects had died in a median follow-up time of 78 months (inter-quartile range 59-93 months). None of the genotypes was clearly associated with total mortality, except variants for two Double-Strand Break DNA repair genes, XRCC3 18067 C>T (rs#861539) and XRCC2 31479 G>A (rs#3218536). Adjusted hazard ratios were 2.25 (1.32-3.83) for the XRCC3 C/T genotype and 2.04 (1.00-4.13) for the T/T genotype (reference C/C), and 2.12 (1.14-3.97) for the XRCC2 G/A genotype (reference G/G). For total cancer mortality, the adjusted hazard ratios were 3.29 (1.23-7.82) for XRCC3 C/T, 2.84 (0.81-9.90) for XRCC3 T/T and 3.17 (1.21-8.30) for XRCC2 G/A. With combinations of three or more adverse alleles, the adjusted hazard ratio for all cause mortality was 17.29 (95% C.I. 8.13-36.74), and for all incident cancers the HR was 5.28 (95% C.I. 2.17-12.85). Observations from this prospective study suggest that polymorphisms of genes involved in the repair of DNA double-strand breaks significantly influence the risk of cancer and non-cancer disease, and can influence mortality.
Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Mortalidade , Neoplasias/epidemiologia , Neoplasias/genética , Polimorfismo Genético , Estudos de Coortes , Predisposição Genética para Doença , Genótipo , Humanos , Incidência , Estudos Prospectivos , Fatores de RiscoRESUMO
The aim of this study is to investigate to what extent occupational exposures may explain socioeconomic inequalities in lung cancer incidence after adjusting for smoking and dietary factors. Analyses were based on a subsample of the European Prospective Investigation into Cancer and Nutrition (EPIC study), a prospective cohort. The analyses included 703 incident lung cancer cases among men in Denmark, the United Kingdom, Germany, Italy, Spain and Greece. The socioeconomic position was measured using the highest level of education. The estimates of relative indices of inequality (RII) were computed with Cox regression models. We first adjusted for smoking (with detailed information on duration and quantity) and dietary factors (fruits and vegetables consumption) and then for occupational exposures. The exposure to three carcinogens [asbestos, heavy metals and polycyclic aromatic hydrocarbons (PAH)] was analyzed. The occupational exposures explained 14% of the socioeconomic inequalities remaining after adjustment for smoking and fruits and vegetables consumption. The inequalities remained nevertheless statistically significant. The RII decreased from 1.87 (95% CI: 1.36-2.56) to 1.75 (1.27-2.41). The decrease was more pronounced when adjusting for asbestos than for heavy metals or PAH. Analyses by birth cohort suggested an effect of occupational exposures among older men, while due to small number of endpoints, no conclusion could be drawn about the role of occupational exposures in educational inequalities among younger men. Our study revealed that the impact of occupational exposures on socioeconomic inequalities in cancer incidence, rarely studied until now, exists while of modest magnitude.
Assuntos
Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Exposição Ocupacional/efeitos adversos , Estudos de Coortes , Escolaridade , Humanos , Incidência , Masculino , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores SocioeconômicosRESUMO
Cigarette smoking is an established risk factor for pancreatic cancer. However, prospective data for most European countries are lacking, and epidemiologic studies on exposure to environmental tobacco smoke (ETS) in relation to pancreatic cancer risk are scarce. We examined the association of cigarette smoking and exposure to ETS with pancreatic cancer risk within the European Prospective Investigation into Cancer and Nutrition (EPIC). This analysis was based on 465,910 participants, including 524 first incident pancreatic cancer cases diagnosed after a median follow-up of 8.9 years. Estimates of risk were obtained by Cox proportional hazard models and adjusted for weight, height, and history of diabetes mellitus. An increased risk of pancreatic cancer was found for current cigarette smokers compared with never smokers (HR = 1.71, 95% CI = 1.36-2.15), and risk increased with greater intensity and pack-years. Former cigarette smokers who quit for less than 5 years were at increased risk of pancreatic cancer (HR = 1.78, 95% CI = 1.23-2.56), but risk was comparable to never smokers after quitting for 5 years or more. Pancreatic cancer risk was increased among never smokers daily exposed to ETS (for many hours) during childhood (HR = 2.61, 95% CI = 0.96-7.10) and exposed to ETS at home and/or work (HR = 1.54, 95% CI = 1.00-2.39). These results suggest that both active cigarette smoking, as well as exposure to ETS, is associated with increased risk of pancreatic cancer and that risk is reduced to levels of never smokers within 5 years of quitting.
Assuntos
Exposição Ambiental/efeitos adversos , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/etiologia , Fumar/efeitos adversos , Fumar/epidemiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Idoso , Estudos de Coortes , Exposição Ambiental/estatística & dados numéricos , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Razão de Chances , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Poluição por Fumaça de Tabaco/estatística & dados numéricosRESUMO
Several prospective studies have shown a moderate positive association between increasing circulating insulin-like growth factor-I (IGF-I) levels and colorectal cancer risk. However, the associations were often statistically nonsignificant, and the relationship of cancer risk with IGF-I's major binding protein, IGFBP-3, showed major discrepancies between studies. We investigated the association of colorectal cancer risk with serum IGF-I, total and intact IGFBP-3, in a case-control study nested within the EPIC cohort (1,121 cases of colorectal cancer and 1,121 matched controls). Conditional logistic regression was used to adjust for possible confounders. Our present study results were combined in a meta-analysis with those from 9 previous prospective studies to examine the overall evidence for a relationship of prediagnostic serum IGF-I with colorectal cancer risk. In the EPIC study, serum concentrations of IGF-I and IGFBP-3 showed no associations with risk of colorectal cancer overall. Only in subgroup analyses did our study show moderate positive associations of IGF-I levels with risk, either among younger participants only (and only for colon cancer) or among participants whose milk intakes were in the lowest tertile of the population distribution (RR for an increase of 100 ng/ml = 1.43 [95% CI = 1.13-1.93]). Nevertheless, in the meta-analysis a modest positive association remained between serum IGF-I and colorectal cancer risk overall (RR = 1.07 [1.01-1.14] for 1 standard deviation increase in IGF-I). Overall, data from our present study and previous prospective studies combined indicate a relatively modest association of colorectal cancer risk with serum IGF-I.
Assuntos
Neoplasias Colorretais/sangue , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Colo/metabolismo , Neoplasias Colorretais/diagnóstico , Dieta , Ensaio de Imunoadsorção Enzimática , Europa (Continente) , Feminino , Seguimentos , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Reto/metabolismo , Fatores de Risco , Taxa de SobrevidaRESUMO
We examined the associations of measured anthropometric factors, including general and central adiposity and height, with ovarian cancer risk. We also investigated these associations by menopausal status and for specific histological subtypes. Among 226,798 women in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, there were 611 incident cases of primary, malignant, epithelial ovarian cancer diagnosed during a mean 8.9 years of follow-up. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), adjusted for potential confounders. Compared to women with body mass index (BMI) < 25 kg/m2, obesity (BMI > or = 30 kg/m2) was associated with excess ovarian cancer risk for all women combined (HR = 1.33, 95% CI = 1.05-1.68; p(trend) = 0.02) and postmenopausal women (HR = 1.59, 95% CI = 1.20-2.10; p(trend) = 0.001), but the association was weaker for premenopausal women (HR = 1.16, 95% CI = 0.65-2.06; p(trend) = 0.65). Neither height or weight gain, nor BMI-adjusted measures of fat distribution assessed by waist circumference, waist-hip ratio (WHR) or hip circumference were associated with overall risk. WHR was related to increased risk of mucinous tumors (BMI-adjusted HR per 0.05 unit increment = 1.17, 95% CI = 1.00-1.38). For all women combined, no other significant associations with risk were observed for specific histological subtypes. This large, prospective study provides evidence that obesity is an important modifiable risk factor for epithelial ovarian cancer, particularly among postmenopausal women.
Assuntos
Carcinoma/epidemiologia , Carcinoma/etiologia , Menopausa , Obesidade/complicações , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/etiologia , Adulto , Idoso , Antropometria , Índice de Massa Corporal , Europa (Continente)/epidemiologia , Feminino , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Análise Multivariada , Estado Nutricional , Obesidade Abdominal/complicações , Razão de Chances , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Circunferência da Cintura , Relação Cintura-QuadrilRESUMO
The imprinted insulin-like growth factor 2 (IGF2) gene is expressed predominantly from the paternal allele. Loss of imprinting (LOI) associated with hypomethylation at the promoter proximal sequence (DMR0) of the IGF2 gene was proposed as a predisposing constitutive risk biomarker for colorectal cancer. We used pyrosequencing to assess whether IGF2 DMR0 methylation is either present constitutively prior to cancer or whether it is acquired tissue-specifically after the onset of cancer. DNA samples from tumour tissues and matched non-tumour tissues from 22 breast and 42 colorectal cancer patients as well as peripheral blood samples obtained from colorectal cancer patients [SEARCH (n=case 192, controls 96)], breast cancer patients [ABC (n=case 364, controls 96)] and the European Prospective Investigation of Cancer [EPIC-Norfolk (n=breast 228, colorectal 225, controls 895)] were analysed. The EPIC samples were collected 2-5 years prior to diagnosis of breast or colorectal cancer. IGF2 DMR0 methylation levels in tumours were lower than matched non-tumour tissue. Hypomethylation of DMR0 was detected in breast (33%) and colorectal (80%) tumour tissues with a higher frequency than LOI indicating that methylation levels are a better indicator of cancer than LOI. In the EPIC population, the prevalence of IGF2 DMR0 hypomethylation was 9.5% and this correlated with increased age not cancer risk. Thus, IGF2 DMR0 hypomethylation occurs as an acquired tissue-specific somatic event rather than a constitutive innate epimutation. These results indicate that IGF2 DMR0 hypomethylation has diagnostic potential for colon cancer rather than value as a surrogate biomarker for constitutive LOI.
Assuntos
Neoplasias da Mama/genética , Neoplasias Colorretais/genética , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento Insulin-Like II/genética , Estudos de Casos e Controles , Feminino , Impressão Genômica , Humanos , Fator de Crescimento Insulin-Like II/metabolismoRESUMO
Women commonly attribute the experience of stress as a contributory cause of breast cancer. The purpose of this study is to investigate the associations between a history of social stress and breast cancer risk. A total of 11,467 women with no prior history of breast cancer, participants in the European Prospective Investigation into Cancer (EPIC)-Norfolk population-based prospective cohort study, completed a comprehensive assessment of lifetime social adversity exposure. Summary measures of social adversity were defined according to difficult circumstances in childhood, stressful life events and longer-term difficulties in adulthood, derived measures representing the subjective 'impact' of life events and associated 'stress adaptive capacity', and perceived stress over a 10-year period. Incident breast cancers were identified through linkage with cancer registry data. During 102,514 (median 9) person-years of follow-up, 313 incident breast cancers were identified. No associations were observed between any of the summary social adversity measures and subsequent breast cancer risk, with or without adjustment for age, menopausal status, parity, use of menopausal hormones, age at menarche, age at first birth, family history of breast cancer, physical activity, social class, body mass index, height, and alcohol intake. This study found no evidence that social stress exposure or individual differences in its experience are associated with the development of breast cancer. These findings may aid strategies designed to meet the psychosocial and emotional needs of breast cancer survivors and may be interpreted in a positive way in the context of commonly voiced beliefs that the experience of stress is a contributory cause of their disease.
Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Neoplasias da Mama/psicologia , Acontecimentos que Mudam a Vida , Estresse Psicológico/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
OBJECTIVE: Cigarette smoking has been reported as "probable" risk factor for Amyotrophic Lateral Sclerosis (ALS), a poorly understood disease in terms of aetiology. The extensive longitudinal data of the European Prospective Investigation into Cancer and Nutrition (EPIC) were used to evaluate age-specific mortality rates from ALS and the role of cigarette smoking on the risk of dying from ALS. METHODS: A total of 517,890 healthy subjects were included, resulting in 4,591,325 person-years. ALS cases were ascertained through death certificates. Cox hazard models were built to investigate the role of smoking on the risk of ALS, using packs/years and smoking duration to study dose-response. RESULTS: A total of 118 subjects died from ALS, resulting in a crude mortality rate of 2.69 per 100,000/year. Current smokers at recruitment had an almost two-fold increased risk of dying from ALS compared to never smokers (HR = 1.89, 95% C.I. 1.14-3.14), while former smokers at the time of enrollment had a 50% increased risk (HR = 1.48, 95% C.I. 0.94-2.32). The number of years spent smoking increased the risk of ALS (p for trend = 0.002). Those who smoked more than 33 years had more than a two-fold increased risk of ALS compared with never smokers (HR = 2.16, 95% C.I. 1.33-3.53). Conversely, the number of years since quitting smoking was associated with a decreased risk of ALS compared with continuing smoking. INTERPRETATION: These results strongly support the hypothesis of a role of cigarette smoking in aetiology of ALS. We hypothesize that this could occur through lipid peroxidation via formaldehyde exposure.
Assuntos
Esclerose Lateral Amiotrófica/etiologia , Esclerose Lateral Amiotrófica/mortalidade , Fumar/efeitos adversos , Adulto , Fatores Etários , Idoso , Esclerose Lateral Amiotrófica/epidemiologia , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Humanos , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Risco , Fatores Sexuais , Inquéritos e QuestionáriosRESUMO
Until recently, the study of nutrient patterns was hampered at an international level by a lack of standardization of both dietary methods and nutrient databases. We aimed to describe the diversity of nutrient patterns in the European Prospective Investigation into Cancer and Nutrition (EPIC) study at population level as a starting point for future nutrient pattern analyses and their associations with chronic diseases in multi-center studies. In this cross-sectional study, 36,034 persons aged 35-74 y were administered a single, standardized 24-h dietary recall. Intake of 25 nutrients (excluding intake from dietary supplements) was estimated using a standardized nutrient database. We used a graphic presentation of mean nutrient intakes by region and sex relative to the overall EPIC means to contrast patterns within and between 10 European countries. In Mediterranean regions, including Greece, Italy, and the southern centers of Spain, the nutrient pattern was dominated by relatively high intakes of vitamin E and monounsaturated fatty acids (MUFA), whereas intakes of retinol and vitamin D were relatively low. In contrast, in Nordic countries, including Norway, Sweden, and Denmark, reported intake of these same nutrients resulted in almost the opposite pattern. Population groups in Germany, The Netherlands, and the UK shared a fatty acid pattern of relatively high intakes of PUFA and SFA and relatively low intakes of MUFA, in combination with a relatively high intake of sugar. We confirmed large variability in nutrient intakes across the EPIC study populations and identified 3 main region-specific patterns with a geographical gradient within and between European countries.
Assuntos
Dieta , Preferências Alimentares , Geografia , Adulto , Idoso , Estudos Transversais , Europa (Continente) , Humanos , Pessoa de Meia-IdadeRESUMO
Immunoslot blot assays have been used for the analysis of many DNA adducts, but problems are frequently encountered in achieving reproducible results. Each step of the assay was examined systematically, and it was found that the major problems are in the DNA fragmentation step and the use of the manifold apparatus. Optimization was performed on both the malondialdehyde-deoxyguanosine (M(1)dG) adduct and the O(6)-carboxymethyl-deoxyguanosine (O(6)CMdG) adduct to demonstrate the applicability to other DNA adducts. Blood samples from the European Prospective Investigation on Cancer (EPIC) study (n = 162) were analyzed for M(1)dG adducts, and the data showed no correlation with adduct levels in other tissues, indicating that the EPIC blood samples were not useful for studying M(1)dG adducts. Blood samples from a processed meat versus vegetarian diet intervention (n = 6) were analyzed for O(6)CMdG, and many were below the limit of detection. The reduction of background adduct levels in standard DNA was investigated using chemical and whole genome amplification approaches. The latter gave a sensitivity improvement of 2.6 adducts per 10(7) nucleotides for the analysis of O(6)CMdG. Subsequent reanalysis for O(6)CMdG showed a weakly significant increase in O(6)CMdG on the processed meat diet compared with the vegetarian diet, demonstrating that further studies are warranted.
Assuntos
Adutos de DNA/sangue , Adutos de DNA/química , Immunoblotting/métodos , Adutos de DNA/imunologia , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Desoxiguanosina/química , Desoxiguanosina/imunologia , Dieta , Europa (Continente) , Humanos , Limite de Detecção , Neoplasias/química , Estudos ProspectivosRESUMO
The association between physical activity, potential intermediate biomarkers and lung cancer risk was investigated in a study of 230 cases and 648 controls nested within the European Prospective Investigation of Cancer and Nutrition. Data on white blood cell aromatic-DNA adducts by (32)P-post-labelling and glutathione (GSH) in red blood cells were available from a subset of cases and controls. Compared with the first quartile, the fourth quartile of recreational physical activity was associated with a lower lung cancer risk (odds ratio (OR) 0.56, 95% confidence interval (CI) 0.35-0.90), higher GSH levels (+1.87 micromol GSH g(-1) haemoglobin, p = 0.04) but not with the presence of high levels of adducts (OR 1.05, 95% CI 0.38-2.86). Despite being associated with recreational physical activity, in these small-scale pilot analyses GSH levels were not associated with lung cancer risk (OR 0.95, 95% CI 0.84-1.07 per unit increase in GSH levels). Household and occupational activity was not associated with lung cancer risk or biomarker levels.
Assuntos
Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Atividade Motora , Fumar , Idoso , Biomarcadores , Estudos de Casos e Controles , Adutos de DNA/análise , Eritrócitos/química , Europa (Continente)/epidemiologia , Feminino , Glutationa/análise , Humanos , Leucócitos/química , Neoplasias Pulmonares/sangue , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular/métodos , Projetos Piloto , Fatores de RiscoRESUMO
The objective of the present study was to investigate the influence of the single nucleotide polymorphism (rs17238540) at the 3-hydroxy-3-methylglutaryl-coenzyme A reductase gene (HMGCR) on the relationship between serum lipids and dietary fat and fibre (NSP). FFQ and pyrosequencing were used to assess cross-sectional dietary intake and HMGCR genotype in a population study with data for serum lipids available. Genotype frequencies and allele distributions for 23 011 participants were: TT 95.65 %, TG 4.29 % and GG 0.06 %; T 97.8 % and G 2.2 %. In regression analyses, the TG+GG group showed a significant positive relationship between TAG and SFA intake (+0.11 (95 % CI 0.02, 0.20) mmol TAG/l; P = 0.017; per 3 % SFA energy increase) while the TT individuals showed no change in the TAG levels related to SFA intake ( - 0.0007 (95 % CI - 0.02, 0.02) mmol TAG/l; P = 0.99). TG+GG individuals showed an inverse relationship between TAG and fibre intake higher ( - 0.14 (95 % CI - 0.22, - 0.05) mmol TAG/l than the TT group ( - 0.04 (95 % CI - 0.06, - 0.02) mmol TAG/l). In both cases the respective coefficient regressions of TAG were different between the genotype groups (Z = 2.27, P = 0.023 for SFA intake; Z = 2.19, P = 0.029 for fibre intake). Individuals carrying the G allele may show a greater response in lower TAG levels with reduced SFA intake and increased fibre intake compared with those homozygous for the T allele. The effectiveness of different dietary interventions to control serum lipids may vary according to HMGCR genotype.