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1.
Int J Cancer ; 147(7): 1917-1927, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32222976

RESUMO

Deficiencies in methyl donor status may render DNA methylation changes and DNA damage, leading to carcinogenesis. Epidemiological studies reported that higher dietary intake of choline is associated with lower risk of pancreatic cancer, but no study has examined the association of serum choline and its metabolites with risk of pancreatic cancer. Two parallel case-control studies, one nested within the Shanghai Cohort Study (129 cases and 258 controls) and the other within the Singapore Chinese Health Study (58 cases and 104 controls), were conducted to evaluate the associations of baseline serum concentrations of choline, betaine, methionine, total methyl donors (i.e., sum of choline, betaine and methionine), dimethylglycine and trimethylamine N-oxide (TMAO) with pancreatic cancer risk. In the Shanghai cohort, odds ratios and 95% confidence intervals of pancreatic cancer for the highest quartile of choline, betaine, methionine, total methyl donors and TMAO were 0.27 (0.11-0.69), 0.57 (0.31-1.05), 0.50 (0.26-0.96), 0.37 (0.19-0.73) and 2.81 (1.37-5.76), respectively, compared to the lowest quartile. The corresponding figures in the Singapore cohort were 0.85 (0.23-3.17), 0.50 (0.17-1.45), 0.17 (0.04-0.68), 0.33 (0.10-1.16) and 1.42 (0.50-4.04). The inverse associations of methionine and total methyl donors including choline, betaine and methionine with pancreatic cancer risk in both cohorts support that DNA repair and methylation play an important role against the development of pancreatic cancer. In the Shanghai cohort, TMAO, a gut microbiota-derived metabolite of dietary phosphatidylcholine, may contribute to higher risk of pancreatic cancer, suggesting a modifying role of gut microbiota in the dietary choline-pancreatic cancer risk association.


Assuntos
Metionina/sangue , Neoplasias Pancreáticas/epidemiologia , Betaína/sangue , Betaína/química , Estudos de Casos e Controles , Colina/sangue , Colina/química , Feminino , Humanos , Masculino , Metilaminas/sangue , Metilaminas/química , Pessoa de Meia-Idade , Razão de Chances , Neoplasias Pancreáticas/sangue , Estudos Prospectivos , Fatores de Risco
2.
Cancer Causes Control ; 30(8): 847-857, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31154549

RESUMO

PURPOSE: Soy isoflavones and tea catechins have immunomodulating and chemopreventive properties relevant for cervical carcinogenesis; however, there are limited epidemiologic data on the relationship of soy and tea consumption with cervical cancer risk. The aim of our study was to examine effects of soy and tea intake on cervical cancer risk among Singapore Chinese women. METHODS: The association between intake of soy and tea drinking and cervical cancer risk was investigated in a prospective, population-based cohort of 30,744 Chinese women in Singapore with an average 16.7 years of follow-up and 312 incident cervical cancer cases. Multivariable proportional hazard models were used to estimate hazard ratio (HR) and 95% confidence interval (CI) of cervical cancer associated with intake levels of soy and tea. RESULTS: High intake of soy alone was associated with a statistically borderline significant 20% reduced risk of cervical cancer (HR 0.80, 95% CI 0.61, 1.05) while green tea alone was not (HR 0.97, 95% CI: 0.76, 1.22). In stratified analysis, high intake of soy was associated with a statistically significant decrease in cervical cancer risk among green tea drinkers (HR 0.43; 95% CI 0.28, 0.69) but not among non-drinkers of green tea. The difference in the soy-cervical cancer risk association between green tea drinkers and non-drinkers was statistically significant (p for interaction = 0.004). This inverse association between soy intake and cervical cancer risk remained after further adjustment for human papillomavirus serostatus. Black tea consumption was not associated with cervical cancer risk. CONCLUSIONS: These findings suggest that a protective effect of soy against cervical cancer development may depend on green tea constituents.


Assuntos
Alimentos de Soja , Chá , Neoplasias do Colo do Útero/epidemiologia , Idoso , Povo Asiático , Feminino , Humanos , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Risco , Singapura/epidemiologia
3.
Carcinogenesis ; 39(3): 336-346, 2018 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-29059373

RESUMO

Non-small cell lung cancer is the most common type of lung cancer. Both environmental and genetic risk factors contribute to lung carcinogenesis. We conducted a genome-wide interaction analysis between single nucleotide polymorphisms (SNPs) and smoking status (never- versus ever-smokers) in a European-descent population. We adopted a two-step analysis strategy in the discovery stage: we first conducted a case-only interaction analysis to assess the relationship between SNPs and smoking behavior using 13336 non-small cell lung cancer cases. Candidate SNPs with P-value <0.001 were further analyzed using a standard case-control interaction analysis including 13970 controls. The significant SNPs with P-value <3.5 × 10-5 (correcting for multiple tests) from the case-control analysis in the discovery stage were further validated using an independent replication dataset comprising 5377 controls and 3054 non-small cell lung cancer cases. We further stratified the analysis by histological subtypes. Two novel SNPs, rs6441286 and rs17723637, were identified for overall lung cancer risk. The interaction odds ratio and meta-analysis P-value for these two SNPs were 1.24 with 6.96 × 10-7 and 1.37 with 3.49 × 10-7, respectively. In addition, interaction of smoking with rs4751674 was identified in squamous cell lung carcinoma with an odds ratio of 0.58 and P-value of 8.12 × 10-7. This study is by far the largest genome-wide SNP-smoking interaction analysis reported for lung cancer. The three identified novel SNPs provide potential candidate biomarkers for lung cancer risk screening and intervention. The results from our study reinforce that gene-smoking interactions play important roles in the etiology of lung cancer and account for part of the missing heritability of this disease.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/etiologia , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/genética , Fumar/efeitos adversos , Estudos de Casos e Controles , Interação Gene-Ambiente , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , População Branca
4.
Int J Cancer ; 142(12): 2425-2434, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29238985

RESUMO

Circulating vitamin B6 levels have been found to be inversely associated with lung cancer. Most studies have focused on the B6 form pyridoxal 5'-phosphate (PLP), a direct biomarker influenced by inflammation and other factors. Using a functional B6 marker allows further investigation of the potential role of vitamin B6 status in the pathogenesis of lung cancer. We prospectively evaluated the association of the functional marker of vitamin B6 status, the 3-hydroxykynurenine:xanthurenic acid (HK:XA) ratio, with risk of lung cancer in a nested case-control study consisting of 5,364 matched case-control pairs from the Lung Cancer Cohort Consortium (LC3). We used conditional logistic regression to evaluate the association between HK:XA and lung cancer, and random effect models to combine results from different cohorts and regions. High levels of HK:XA, indicating impaired functional B6 status, were associated with an increased risk of lung cancer, the odds ratio comparing the fourth and the first quartiles (OR4thvs.1st ) was 1.25 (95% confidence interval, 1.10-1.41). Stratified analyses indicated that this association was primarily driven by cases diagnosed with squamous cell carcinoma. Notably, the risk associated with HK:XA was approximately 50% higher in groups with a high relative frequency of squamous cell carcinoma, i.e., men, former and current smokers. This risk of squamous cell carcinoma was present in both men and women regardless of smoking status.


Assuntos
Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/patologia , Vitamina B 6/sangue , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco
5.
Cancer Causes Control ; 29(1): 51-62, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29124543

RESUMO

PURPOSE: Mechanistic and observational data together support a role for prolactin in breast cancer development. Determinants of prolactin in Asian populations have not been meaningfully explored, despite the lower risk of breast cancer in Asian populations. METHODS: Determinants of plasma prolactin were evaluated in 442 postmenopausal women enrolled in the Singapore Chinese Health Study, a population-based prospective cohort study. At baseline all cohort members completed an in-person interview that elicited information on diet, menstrual and reproductive history, and lifestyle factors. One year after cohort initiation we began collecting blood samples. Quantified were plasma concentrations of prolactin, estrone, estradiol, testosterone, androstenedione, and sex hormone-binding globulin (SHBG). Analysis of covariance method was used for statistical analyses with age at blood draw, time since last meal, and time at blood draw as covariates. RESULTS: Mean prolactin levels were 25.1% lower with older age at menarche (p value = 0.001), and 27.6% higher with greater years between menarche and menopause (p value = 0.009). Prolactin levels were also positively associated with increased sleep duration (p value = 0.005). The independent determinants of prolactin were years from menarche to menopause, hours of sleep, and the plasma hormones estrone and SHBG (all p values < 0.01). CONCLUSION: The role of prolactin in breast cancer development may involve reproductive and lifestyle factors, such as a longer duration of menstrual cycling and sleep patterns.


Assuntos
Neoplasias da Mama/sangue , Menopausa/sangue , Prolactina/sangue , Idoso , Feminino , Hormônios Esteroides Gonadais/sangue , Humanos , Estilo de Vida , Menarca , Ciclo Menstrual , Pessoa de Meia-Idade , Estudos Prospectivos , História Reprodutiva , Fatores de Risco , Globulina de Ligação a Hormônio Sexual/análise , Singapura , Sono
6.
BMC Cancer ; 18(1): 220, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29471809

RESUMO

BACKGROUND: Obesity has been proposed as a potential protective factor against lung cancer. We examined the association between BMI and lung cancer risk in a pooled analysis based on nested case-control studies from four cohort studies. METHODS: A case-control study was nested within four cohorts in USA, Europe, China and Singapore that included 4172 cases and 8471 control subjects. BMI at baseline was calculated as weight in kilograms divided by height in meters squared (kg/m2), and classified into 4 categories: underweight (BMI < 18.5), normal weight (18.5 ≤ BMI < 25), overweight (25 ≤ BMI < 30) and obese (≥30). Odds ratios (ORs) and 95% confidence intervals (CIs) for BMI-lung cancer associations were estimated using unconditional logistic regression, adjusting for potential confounders. RESULTS: Considering all participants, and using normal weight as the reference group, a decreased risk of lung cancer was observed for those who were overweight (OR 0.77, 95% CI: 0.68-0.86) and obese (OR 0.69, 95% CI: 0.59-0.82). In the stratified analysis by smoking status, the decreased risk for lung cancer was observed among current, former and never smokers (P for interaction 0.002). The adjusted ORs for overweight and obese groups were 0.79 (95% CI: 0.68-0.92) and 0.75 (95% CI: 0.60-0.93) for current smokers, 0.70 (95% CI: 0.53-0.93) and 0.55 (95% CI: 0.37-0.80) for former smokers, 0.77 (95% CI: 0.59-0.99), and 0.71 (95% CI: 0.44-1.14) for never smokers, respectively. While no statistically significant association was observed for underweight subjects who were current smokers (OR 1.24, 95% CI: 0.98-1.58), former smokers (OR 0.27, 95% CI: 0.12-0.61) and never smokers (OR 0.83, 95% CI: 0.5.-1.28). CONCLUSION: The results of this study provide additional evidence that obesity is associated with a decreased risk of lung cancer. Further biological studies are needed to address this association.


Assuntos
Neoplasias Pulmonares/etiologia , Sobrepeso/complicações , Adulto , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Fatores de Risco , Fumar/efeitos adversos
7.
Int J Cancer ; 141(12): 2450-2461, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-28842914

RESUMO

Accumulating evidence suggests that the aggregation of common metabolic conditions (high blood pressure, diabetes and dyslipidemia) is a risk factor for breast cancer. Breast cancer incidence has risen steadily in Asian American women, and whether these metabolic conditions contribute to breast cancer risk in certain Asian American subgroups is unknown. We investigated the role of physician-diagnosed hypertension, high cholesterol and diabetes separately, and in combination, in relation to the risk of breast cancer in a population-based case-control study of 2,167 Asian Americans diagnosed with breast cancer and 2,035 age and ethnicity matched control women in Los Angeles County. Compared to Asian American women who did not have any of the metabolic conditions, those with 1, 2 or 3 conditions showed a steady increase in risk (respective odds ratios were 1.12, 1.42 and 1.62; P trend = 0.001) with adjustment for covariates including body mass index. Similar significant trends were observed in Filipina Americans (P trend = 0.021), postmenopausal women (P trend =0.001), Asian women who were born in the United States (US) (P trend = 0.052) and migrants who have lived in the US for at least 20 years (P trend = 0.004), but not migrants who lived in the US for <20 years (P trend = 0.64). These results suggest that westernization in lifestyle (diet and physical inactivity) and corresponding increase in adiposity have contributed to the rising prevalence of these metabolic conditions, which in turn, are associated with an increase in breast cancer.


Assuntos
Asiático/classificação , Neoplasias da Mama/epidemiologia , Síndrome Metabólica/complicações , Adulto , Distribuição por Idade , Idoso , Neoplasias da Mama/etnologia , Neoplasias da Mama/etiologia , Estudos de Casos e Controles , China/etnologia , Feminino , Humanos , Incidência , Japão/etnologia , Estilo de Vida , Los Angeles/epidemiologia , Síndrome Metabólica/etnologia , Pessoa de Meia-Idade , Razão de Chances , Filipinas/etnologia
8.
Int J Cancer ; 138(12): 2837-45, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26829904

RESUMO

Gastric cancer incidence varies greatly worldwide, but is consistently twice as high in men than in women. The hormone-related factors hypothesized to be associated with lower risk of gastric cancer in women have not been fully explored in populations with a high background risk of gastric cancer. The Singapore Chinese Health Study (SCHS) is a prospective cohort study in which 34,022 of the participants enrolled between 1993 and 1998 were women between 45 and 74 years of age. Information on reproductive histories, hormone replacement therapy (HRT) and oral contraceptive (OC) use was collected through in-person interviews at baseline. As of December 31, 2013, 269 incident gastric cancer cases were identified. Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to evaluate gastric cancer risk associations. Older age at natural menopause (≥55 versus <45 years: HR = 0.50, 95% CI: 0.25-0.99), type of menopause (other versus natural: HR = 0.48, 95% CI: 0.27-0.87) and greater years of menstrual cycling (fourth versus first quartile: HR = 0.67, 95% CI: 0.46-0.96) were associated with a decreased risk of gastric cancer. Ever use of OCs and HRT was also associated with reduced risk of gastric cancer; the multivariable-adjusted HRs (95% CIs) were 0.40 (0.17-0.90) for use of HRT >3 years and 0.67 (0.47-0.94) for ever use of OCs, compared with never use. Reproductive factors associated with a longer window of fertility and the use of exogenous hormones were shown to reduce gastric cancer development in a cohort of Chinese women with a high background risk of gastric cancer.


Assuntos
Terapia de Reposição Hormonal , Neoplasias Gástricas/epidemiologia , Adulto , China/etnologia , Anticoncepcionais Orais Hormonais/administração & dosagem , Estrogênios/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Proteção , Singapura , Neoplasias Gástricas/prevenção & controle
9.
Int J Cancer ; 138(9): 2161-71, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26662855

RESUMO

Cytochrome P450 2A6 (CYP2A6) catalyzes nicotine metabolism and contributes to the metabolism of the tobacco-specific lung carcinogen, NNK. Genetic variation in CYP2A6 may affect smoking behavior and contribute to lung cancer risk. A nested case-control study of 325 lung cancer cases and 356 controls was conducted within a prospective cohort of 18,244 Chinese men in Shanghai, China. Quantified were 4 allelic variants of CYP2A6 [*1(+51A), *4, *7, and *9] and urinary total nicotine, total cotinine, total trans-3'-hydroxycotinine (3HC) and total NNAL (an NNK metabolite). Calculated were total nicotine equivalents (TNE), the sum of total nicotine, total cotinine and total 3HC and the total 3HC:total cotinine ratio as a measure of CYP2A6 activity. The nicotine metabolizer status (normal, intermediate, slow and poor) was determined by CYP2A6 genotypes. The smoking-adjusted odds ratios (95% confidence intervals) of lung cancer for the highest vs lowest quartile of total nicotine, total cotinine, total 3HC, TNE and total NNAL were 3.03 (1.80-5.10), 4.70 (2.61-8.46), 4.26 (2.37-7.68), 4.71 (2.61-8.52), and 3.15 (1.86-5.33) (all Ptrend < 0.001), respectively. Among controls CYP2A6 poor metabolizers had a 78% lower total 3HC:total cotinine ratio and 72% higher total nicotine (Ptrend ≤ 0.002). Poor metabolizers had an odds ratio of 0.64 (95% confidence interval = 0.43-0.97) for lung cancer, which was statistically nonsignificant (odds ratio = 0.74, 95% confidence interval = 0.48-1.15) after adjustment for urinary TNE and smoking intensity and duration. The lower lung cancer risk observed in CYP2A6 poor metabolizers is partially explained by the strong influence of CYP2A6 genetic polymorphisms on nicotine uptake and metabolism.


Assuntos
Povo Asiático/genética , Citocromo P-450 CYP2A6/genética , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/genética , Nicotina/metabolismo , Fumar/efeitos adversos , Biomarcadores Tumorais/análise , Estudos de Casos e Controles , China , Estudos de Coortes , Cotinina/metabolismo , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/genética , Razão de Chances , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fumar/genética
10.
Cancer Causes Control ; 27(12): 1447-1456, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27830400

RESUMO

BACKGROUND: Vitamin B6 is an important enzymatic cofactor in pathways relevant for the development of pancreatic cancer. In order to evaluate vitamin B6 as a preventive factor for pancreatic cancer, a biomarker approach is needed to overcome the limitations inherent in self-reported dietary information. METHODS: To determine whether levels of serum B6 vitamers, including pyridoxal 5'-phosphate (PLP), pyridoxal (PL), 4-pyridoxic acid (PA), and the PA/(PLP + PL) ratio (PAr), were associated with risk of pancreatic cancer, two nested case-control studies of 187 incident pancreatic cancer cases and 258 individually matched controls were conducted within two prospective cohorts of 81,501 participants in Shanghai, China, and Singapore. PLP, PL, and PA were quantified in pre-diagnostic serum samples. Odds ratios and 95% confidence intervals (CIs) were calculated using conditional logistic regression with adjustment for potential confounders. RESULTS: The median (5th-95th percentiles) concentrations of serum PLP among control subjects of the Shanghai and Singapore cohorts were 25.7 (10.0-91.7) nmol/L and 58.1 (20.8-563.0) nmol/L, respectively. In pooled analyses, high serum PLP was associated with a reduced risk of pancreatic cancer (P for trend = 0.048); the adjusted odds ratio for the highest category of PLP (>52.4 nmol/L) was 0.46 (95% CI 0.23, 0.92) compared to vitamin B6 deficiency (<20 nmol/L). No associations were found for serum PL, PA, or PAr with pancreatic cancer risk. CONCLUSIONS: Higher concentrations of PLP may protect against the development of pancreatic cancer. The protective effect may be more apparent in populations with low concentrations of circulating vitamin B6.


Assuntos
Neoplasias Pancreáticas/sangue , Fosfato de Piridoxal/sangue , Piridoxal/sangue , Ácido Piridóxico/sangue , Idoso , Povo Asiático , Biomarcadores Tumorais/sangue , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/epidemiologia , Estudos Prospectivos , Fatores de Risco , Singapura/epidemiologia , Vitamina B 6/sangue , Complexo Vitamínico B/sangue
11.
Int J Cancer ; 137(11): 2688-95, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26095604

RESUMO

Prospective studies conducted in Western populations have suggested that alterations in soluble CD27 (sCD27) and soluble CD30 (sCD30), two markers indicative of B-cell activation, are associated with risk of non-Hodgkin lymphoma (NHL). Given that the characteristics of NHL in East Asia differ from the West and mechanistic commonalities between these populations with respect to the role of intermediate endpoint biomarkers in lymphomagenesis have not been explored, we conducted a pooled nested case-control study from three prospective studies of Chinese men and women including 218 NHL cases and 218 individually matched controls. Compared with the lowest quartile, ORs (95% CIs) for the second, third and fourth quartiles of sCD27 were 1.60 (0.83-3.09), 1.94 (0.98-3.83) and 4.45 (2.25-8.81), respectively (p(trend) = 0.000005). The corresponding ORs for sCD30 were 1.74 (0.85-3.58), 1.86 (0.94-3.67) and 5.15 (2.62-10.12; p(trend) = 0.0000002). These associations remained statistically significant in individuals diagnosed with NHL 10 or more years after blood draw. Notably, the magnitude of the associations with NHL risk was very similar to those in Western populations in previous studies. These findings of the similar association between sCD27 or sCD30 and NHL risk across different populations support an important underlying mechanism of B-cell activation in lymphomagenesis.


Assuntos
Antígeno Ki-1/imunologia , Ativação Linfocitária/imunologia , Linfoma não Hodgkin/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Adulto , Idoso , Povo Asiático , Linfócitos B/imunologia , Biomarcadores Tumorais/imunologia , Estudos de Casos e Controles , Ásia Oriental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Risco , Fatores de Risco
12.
Am J Epidemiol ; 181(6): 397-405, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25713334

RESUMO

Dietary catechins are phytochemicals with both antioxidative and prooxidative stress properties. Green tea is a major source of catechins and may be associated with hepatocellular carcinoma (HCC) risk, but the catechin-HCC relationship has not been evaluated using a biomarker-based approach. A nested case-control study of HCC (211 cases and 1,067 matched controls) was conducted within the Shanghai Cohort Study, which enrolled 18,244 men between 1986 and 1989. Concentrations of specific catechins, including epicatechin, epigallocatechin (EGC), and 4'-O-methyl-epigallocatechin, were measured in urine specimens that had been collected prior to HCC diagnosis. None of the catechins measured were associated with HCC risk. In stratified analyses, there was a statistically significant trend for an association of higher urinary EGC with increased HCC risk among subjects with positive serology for hepatitis B surface antigen (P for trend = 0.02). This positive EGC-HCC association became stronger for hepatitis B surface antigen-positive persons who also had low serum retinol levels (for detectable levels vs. undetectable levels, odds ratio = 2.62, 95% confidence interval: 1.25, 5.51). There was no evidence supporting a protective role of catechins in the development of HCC. Instead, exposure to high levels of catechins may increase the risk of developing HCC for high-risk individuals.


Assuntos
Carcinoma Hepatocelular/urina , Catequina/análogos & derivados , Neoplasias Hepáticas/urina , Biomarcadores/urina , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/etiologia , Estudos de Casos e Controles , Catequina/urina , China , Estudos de Coortes , Antígenos de Superfície da Hepatite B/sangue , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Chá , Vitamina A/sangue
13.
Am J Epidemiol ; 182(5): 381-9, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26243736

RESUMO

Many potentially modifiable risk factors for prostate cancer are also associated with prostate cancer screening, which may induce a bias in epidemiologic studies. We investigated the associations of body mass index (weight (kg)/height (m)(2)), smoking, and alcohol consumption with risk of fatal prostate cancer in Asian countries where prostate cancer screening is not widely utilized. Analysis included 18 prospective cohort studies conducted during 1963-2006 across 6 countries in southern and eastern Asia that are part of the Asia Cohort Consortium. Body mass index, smoking, and alcohol intake were determined by questionnaire at baseline, and cause of death was ascertained through death certificates. Analysis included 522,736 men aged 54 years, on average, at baseline. During 4.8 million person-years of follow-up, there were 634 prostate cancer deaths (367 prostate cancer deaths across the 11 cohorts with alcohol data). In Cox proportional hazards analyses of all cohorts in the Asia Cohort Consortium, prostate cancer mortality was not significantly associated with obesity (body mass index >25: hazard ratio (HR) = 1.08, 95% confidence interval (CI): 0.85, 1.36), ever smoking (HR = 1.00, 95% CI: 0.84, 1.21), or heavy alcohol intake (HR = 1.00, 95% CI: 0.74, 1.35). Differences in prostate cancer screening and detection probably contribute to differences in the association of obesity, smoking, or alcohol intake with prostate cancer risk and mortality between Asian and Western populations and thus require further investigation.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Índice de Massa Corporal , Obesidade/epidemiologia , Neoplasias da Próstata/epidemiologia , Fumar/epidemiologia , Ásia , Peso Corporal , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Neoplasias da Próstata/mortalidade , Fatores de Risco
14.
Cancer Causes Control ; 26(3): 431-42, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25604866

RESUMO

PURPOSE: High mammographic density (MD) is a strong risk factor for breast cancer. Chronic inflammation may be related to breast cancer risk through a mechanism involving the percent of breast area that is dense (percent MD). Longitudinal assessments, however, are lacking and thus were constructed to evaluate the relationship between chronic inflammation and percent MD. METHODS: We evaluated whether elevated (>3 mg/L) high-sensitivity C-reactive protein (hsCRP), a biomarker of inflammation, was associated with change in percent MD among 653 women aged 42-52 years at baseline in the Study of Women's Health Across the Nation, a longitudinal study of midlife women. We used a mixed model to analyze data from an average of 4.7 mammograms per woman collected during an average follow-up of 4.9 years (SD = 1.47). RESULTS: Elevated hsCRP at baseline was associated with lower baseline percent MD and a significantly slower annual decline over time of percent MD in an adjusted model that did not include body mass index (BMI) (ß = 0.88, 95 % CI 0.44, 1.31). This association was attenuated and nonsignificant when BMI was included in the model (ß = 0.37, 95 % CI -0.09, 0.84). Elevated hsCRP levels over time (time-varying elevated hsCRP levels) were also associated with a significantly slower decline in percent MD (ß = 0.62, 95 % CI 0.30, 0.94). This association was attenuated, but still significant after adjusting for baseline BMI (ß = 0.40, 95 % CI 0.07, 0.73). CONCLUSION: These results suggest that inflammation may be related to slower reduction in percent MD.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mama/patologia , Proteína C-Reativa/biossíntese , Glândulas Mamárias Humanas/anormalidades , Mamografia/métodos , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Densidade da Mama , Estudos de Coortes , Feminino , Humanos , Inflamação , Estudos Longitudinais , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo
15.
Carcinogenesis ; 35(2): 339-45, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24148823

RESUMO

Exposures to polycyclic aromatic hydrocarbons (PAHs) from various environmental and occupational sources are considered a primary risk factor for lung cancer among lifelong never smokers, based largely on results from epidemiologic studies utilizing self-reported exposure information. Prospective, biomarker-based human studies on the role of PAH and other airborne carcinogens in the development of lung cancer among lifelong non-smokers have been lacking. We prospectively investigated levels of urinary metabolites of a PAH and volatile organic compounds in relation to lung cancer risk in a nested case-control study of 82 cases and 83 controls among lifelong never smokers of the Shanghai Cohort Study, a prospective cohort of 18 244 Chinese men aged 45-64 years at enrollment. We quantified three PAH metabolites: r-1,t-2,3,c-4-tetrahydroxy-1,2,3,4-tetrahydrophenanthrene (PheT), 3-hydroxyphenanthrene (3-OH-Phe) and total hydroxyphenanthrenes (total OH-Phe, the sum of 1-, 2-, 3- and 4-OH-Phe), as well as metabolites of the volatile organic compounds acrolein (3-hydroxypropyl mercapturic acid), benzene (S-phenyl mercapturic acid), crotonaldehyde (3-hydroxy-1-methylpropylmercapturic acid) and ethylene oxide (2-hydroxyethyl mercapturic acid). Urinary cotinine was also quantified to confirm non-smoking status. Compared with the lowest quartile, odds ratios (95% confidence intervals) for lung cancer risk for the highest quartile levels of PheT, 3-OH-Phe and total OH-Phe were 2.98 (1.13-7.87), 3.10 (1.12-7.75) and 2.59 (1.01-6.65) (all P trend < 0.05), respectively. None of the metabolites of the volatile organic compounds were associated with overall lung cancer risk. This study demonstrates a potentially important role of exposure to PAH in the development of lung cancer among lifelong never smokers.


Assuntos
Biomarcadores Tumorais/urina , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/urina , Hidrocarbonetos Policíclicos Aromáticos/urina , Fumar/efeitos adversos , Compostos Orgânicos Voláteis/urina , Estudos de Casos e Controles , China , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
16.
PLoS Med ; 11(4): e1001631, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24756146

RESUMO

BACKGROUND: Tobacco smoking is a major risk factor for many diseases. We sought to quantify the burden of tobacco-smoking-related deaths in Asia, in parts of which men's smoking prevalence is among the world's highest. METHODS AND FINDINGS: We performed pooled analyses of data from 1,049,929 participants in 21 cohorts in Asia to quantify the risks of total and cause-specific mortality associated with tobacco smoking using adjusted hazard ratios and their 95% confidence intervals. We then estimated smoking-related deaths among adults aged ≥45 y in 2004 in Bangladesh, India, mainland China, Japan, Republic of Korea, Singapore, and Taiwan-accounting for ∼71% of Asia's total population. An approximately 1.44-fold (95% CI = 1.37-1.51) and 1.48-fold (1.38-1.58) elevated risk of death from any cause was found in male and female ever-smokers, respectively. In 2004, active tobacco smoking accounted for approximately 15.8% (95% CI = 14.3%-17.2%) and 3.3% (2.6%-4.0%) of deaths, respectively, in men and women aged ≥45 y in the seven countries/regions combined, with a total number of estimated deaths of ∼1,575,500 (95% CI = 1,398,000-1,744,700). Among men, approximately 11.4%, 30.5%, and 19.8% of deaths due to cardiovascular diseases, cancer, and respiratory diseases, respectively, were attributable to tobacco smoking. Corresponding proportions for East Asian women were 3.7%, 4.6%, and 1.7%, respectively. The strongest association with tobacco smoking was found for lung cancer: a 3- to 4-fold elevated risk, accounting for 60.5% and 16.7% of lung cancer deaths, respectively, in Asian men and East Asian women aged ≥45 y. CONCLUSIONS: Tobacco smoking is associated with a substantially elevated risk of mortality, accounting for approximately 2 million deaths in adults aged ≥45 y throughout Asia in 2004. It is likely that smoking-related deaths in Asia will continue to rise over the next few decades if no effective smoking control programs are implemented. Please see later in the article for the Editors' Summary.


Assuntos
Doenças Cardiovasculares/mortalidade , Neoplasias/mortalidade , Doenças Respiratórias/mortalidade , Fumar/mortalidade , Adulto , Ásia/epidemiologia , Doenças Cardiovasculares/economia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Efeitos Psicossociais da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/economia , Neoplasias/epidemiologia , Neoplasias/etiologia , Prevalência , Doenças Respiratórias/economia , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/etiologia , Risco , Fatores de Risco , Fumar/economia , Fumar/epidemiologia
17.
J Nutr ; 144(4): 511-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24572035

RESUMO

Data on overall dietary pattern and osteoporotic fracture risk from population-based cohorts are limited, especially from Asian populations. This study examined the relation between overall diet and hip fracture risk by using principal components analysis (PCA) to identify dietary pattern specific to the study population and by using the Alternative Healthy Eating Index (AHEI) 2010 to assess dietary quality. The Singapore Chinese Health Study is a prospective population-based cohort that enrolled 63,257 Chinese men and women (including both pre- and postmenopausal women) aged 45-74 y between 1993 and 1998 in Singapore. Habitual diet was assessed by using a validated food-frequency questionnaire. Two dietary patterns, the vegetable-fruit-soy (VFS) pattern and the meat-dim-sum (MDS) pattern, were derived by PCA. Overall dietary quality was assessed according to the AHEI 2010, which was defined a priori for chronic disease prevention. A Cox regression model was applied with adjustment for potential confounders. In both genders, higher scores for the VFS pattern and the AHEI 2010 were associated with lower risk of hip fracture in a dose-dependent manner (all P-trend ≤ 0.008). Compared with the lowest quintile, participants in the highest quintile had a 34% reduction in risk (HR: 0.66; 95% CI: 0.55, 0.78) for the VFS pattern and a 32% reduction in risk (HR: 0.68; 95% CI: 0.58, 0.79) for the AHEI 2010. The MDS pattern score was not associated with hip fracture risk. An Asian diet rich in plant-based foods, namely vegetables, fruit, and legumes such as soy, may reduce the risk of hip fracture.


Assuntos
Comportamento Alimentar , Frutas , Fraturas do Quadril/prevenção & controle , Política Nutricional , Cooperação do Paciente , Alimentos de Soja , Verduras , Idoso , Estudos de Coortes , Comportamento Alimentar/etnologia , Feminino , Promoção da Saúde , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/etnologia , Humanos , Incidência , Perda de Seguimento , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etnologia , Fraturas por Osteoporose/prevenção & controle , Cooperação do Paciente/etnologia , Análise de Componente Principal , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Singapura
18.
Mutat Res ; 762: 24-31, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24607854

RESUMO

PURPOSE: Much of the DNA damage from colon cancer-related carcinogens, including heterocyclic amines (HCA) and polycyclic aromatic hydrocarbons (PAH) from red meat cooked at high temperature, are repaired by the nucleotide excision repair (NER) pathway. Thus, we examined whether NER non-synonymous single nucleotide polymorphisms (nsSNPs) modified the association between red meat intake and colon cancer risk. METHODS: The study consists of 244 African-American and 311 white colon cancer cases and population-based controls (331 African Americans and 544 whites) recruited from 33 counties in North Carolina from 1996 to 2000. Information collected by food frequency questionnaire on meat intake and preparation methods were used to estimate HCA and benzo(a)pyrene (BaP, a PAH) intake. We tested 7 nsSNPs in 5 NER genes: XPC A499V and K939Q, XPD D312N and K751Q, XPF R415Q, XPG D1104H, and RAD23B A249V. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression. RESULTS: Among African Americans, we observed a statistically significant positive association between colon cancer risk and XPC 499 AV+VV genotype (OR=1.7, 95% CI: 1.1, 2.7, AA as referent), and an inverse association with XPC 939 QQ (OR=0.3, 95%CI: 0.2, 0.8, KK as referent). These associations were not observed among whites. For both races combined, there was interaction between the XPC 939 genotype, well-done red meat intake and colon cancer risk (OR=1.5, 95% CI=1.0, 2.2 for high well-done red meat and KK genotype as compared to low well-done red meat and KK genotype, pinteraction=0.05). CONCLUSIONS: Our data suggest that NER nsSNPs are associated with colon cancer risk and may modify the association between well-done red meat intake and colon cancer risk.


Assuntos
Adenocarcinoma/genética , Neoplasias do Colo/genética , Reparo do DNA , Proteínas de Ligação a DNA/genética , Carne/efeitos adversos , Polimorfismo de Nucleotídeo Único , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/etnologia , Adulto , Negro ou Afro-Americano , Idoso , Idoso de 80 Anos ou mais , Animais , Benzopirenos/administração & dosagem , Carcinógenos/administração & dosagem , Bovinos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/etnologia , Culinária , Feminino , Genótipo , Compostos Heterocíclicos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , North Carolina , Razão de Chances , Risco , Inquéritos e Questionários , População Branca
19.
Carcinogenesis ; 34(8): 1794-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23568952

RESUMO

Probable human carcinogens are generated during Chinese-style high-temperature cooking of meat and have been detected in the ambient air and on the meat surface. Although the inhalation of these compounds is an established risk factor for lung cancer, exposure via fried meat consumption has not yet been prospectively evaluated as a risk factor. The relationship between fried meat intake and lung cancer risk was investigated using data from a prospective cohort study among Chinese in Singapore. Lung cancer cases (n = 1130) were identified from 61 321 men and women, 70% of whom were lifetime never smokers. Proportional hazards regression methods were used to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). Overall, there was no association between fried meat intake and risk of all lung cancers combined. For lung adenocarcinoma, fried meat intake had a statistically significant association with increased risk. The association between fried meat intake and risk of lung adenocarcinoma became stronger when analyses were restricted to lifetime never smokers. Compared with the lowest tertile of fried meat intake, the HRs (95% CIs) for the second and third tertiles were 1.43 (0.98, 2.08) and 1.51 (1.03, 2.22), respectively (P for trend = 0.04). The positive association was present among both men and women. There was no association between fried meat intake and risk of non-adenocarcinomas of the lung. Our prospective results for fried meat intake support consumption as an important route of exposure to compounds from Chinese-style high-temperature cooking for the development of lung adenocarcinoma.


Assuntos
Adenocarcinoma/epidemiologia , Comportamento Alimentar , Neoplasias Pulmonares/epidemiologia , Carne/estatística & dados numéricos , Adenocarcinoma/etiologia , Adenocarcinoma de Pulmão , Povo Asiático , Carcinógenos/administração & dosagem , Estudos de Coortes , Intervalos de Confiança , Culinária/métodos , Feminino , Temperatura Alta , Humanos , Neoplasias Pulmonares/etiologia , Masculino , Carne/efeitos adversos , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Singapura/epidemiologia , Fumar
20.
Int J Cancer ; 133(3): 680-6, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23319293

RESUMO

There is experimental evidence that calcium protects against breast cancer development. Prospective epidemiologic studies supporting a protective effect of calcium on breast cancer risk have mainly been limited to Western populations. We examined the association between calcium intake and breast cancer risk in the Singapore Chinese Health Study, a large population-based prospective cohort. Calcium intake and supplement use was assessed by in-person interviewer using a validated food frequency questionnaire. After a mean follow-up of 14.2±3.5 years, 823 cohort participants developed invasive breast cancer. Multivariate proportional hazards regression models were fitted to examine the associations between calcium intake and breast cancer risk. Vegetables were the primary food source of calcium in this study population, followed by dairy products, grains and soy foods. Calcium intake was not associated with breast cancer risk, comparing highest quartile (>345.6 mg/1,000 kcal/day) to lowest quartile (<204.5 mg/1,000 kcal/day) of intake. There was no evidence of effect modification by menopausal status, body mass index, dietary vitamin D or stage of disease at diagnosis. Our findings do not support a hypothesis for calcium in breast cancer chemoprevention, contrary to findings from previous studies among Western populations with higher calcium intake primarily from dairy products and supplements.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/prevenção & controle , Cálcio da Dieta/administração & dosagem , China/epidemiologia , Laticínios , Dieta , Suplementos Nutricionais , Ingestão de Alimentos , Grão Comestível , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Modelos de Riscos Proporcionais , Fatores de Risco , Singapura/epidemiologia , Alimentos de Soja , Inquéritos e Questionários , Verduras , Vitamina D
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