| 1. |
- Baltar, Valéria Troncoso, et al.
(författare)
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A structural equation modelling approach to explore the role of B vitamins and immune markers in lung cancer risk
- 2013
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Ingår i: European Journal of Epidemiology. - : Springer Science and Business Media LLC. - 0393-2990 .- 1573-7284. ; 28:8, s. 677-688
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Tidskriftsartikel (refereegranskat)abstract
- The one-carbon metabolism (OCM) is considered key in maintaining DNA integrity and regulating gene expression, and may be involved in the process of carcinogenesis. Several B-vitamins and amino acids have been implicated in lung cancer risk, via the OCM directly as well as immune system activation. However it is unclear whether these factors act independently or through complex mechanisms. The current study applies structural equations modelling (SEM) to further disentangle the mechanisms involved in lung carcinogenesis. SEM allows simultaneous estimation of linear relations where a variable can be the outcome in one equation and the predictor in another, as well as allowing estimation using latent variables (factors estimated by correlation matrix). A large number of biomarkers have been analysed from 891 lung cancer cases and 1,747 controls nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Four putative mechanisms in the OCM and immunity were investigated in relation to lung cancer risk: methionine-homocysteine metabolism, folate cycle, transsulfuration, and mechanisms involved in inflammation and immune activation, all adjusted for tobacco exposure. The hypothesized SEM model confirmed a direct and protective effect for factors representing methionine-homocysteine metabolism (p = 0.020) and immune activation (p = 0.021), and an indirect protective effect of folate cycle (p = 0.019), after adjustment for tobacco smoking. In conclusion, our results show that in the investigation of the involvement of the OCM, the folate cycle and immune system in lung carcinogenesis, it is important to consider complex pathways (by applying SEM) rather than the effects of single vitamins or nutrients (e.g. using traditional multiple regression). In our study SEM were able to suggest a greater role of the methionine-homocysteine metabolism and immune activation over other potential mechanisms.
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| 2. |
- Baltar, Valéria Troncoso, et al.
(författare)
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Smoking, secondhand smoke, and cotinine levels in a subset of EPIC cohort
- 2011
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research. - 1055-9965 .- 1538-7755. ; 20:5, s. 869-875
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Tidskriftsartikel (refereegranskat)abstract
- Background: Several countries are discussing new legislation regarding the ban on smoking in public places, based on the growing evidence of the hazards of secondhand smoke (SHS) exposure. The objective of the present study is to quantitatively assess the relationship between smoking, SHS, and serum cotinine levels in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Methods: From a study on lung cancer in the EPIC cohort, questionnaire information on smoking was collected at enrolment, and cotinine was measured in serum. Three statistical models were applied by using samples available in a cross-section design: (i) cotinine levels by categories combining smoking and SHS (n = 859); (ii) the effect of hours of passive smoking exposure in nonsmokers only (n = 107); (iii) the effect of the number of cigarettes consumed per day in current smokers only (n = 832). All models were adjusted for country, sex, age, and body mass index. Results: Among nonsmokers, passive smokers presented significant differences in cotinine compared with nonexposed, with a marked (but not significant) difference among former-smokers. A one hour per day increment of SHS gave rise to a significant 2.58 nmol/L (0.45 ng/mL) increase in mean serum cotinine (P < 0.001). In current smokers, a one cigarette per day increment gave rise to a significant 22.44 nmol/L (3.95 ng/mL) increase in cotinine mean (P < 0.001). Conclusions: There is clear evidence that not only tobacco smoking but also involuntary exposure increases cotinine levels. Impact: This study strengthens the evidence for the benefits of a smoking ban in public places.
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| 3. |
- Chuang, Shu-Chun, et al.
(författare)
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Circulating Biomarkers of Tryptophan and the Kynurenine Pathway and Lung Cancer Risk
- 2014
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - 1055-9965 .- 1538-7755. ; 23:3, s. 461-468
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Tidskriftsartikel (refereegranskat)abstract
- Background: Imbalances in tryptophan metabolism have been linked to cancer-related immune escape and implicated in several cancers, including lung cancer. Methods: We conducted a nested case-control study within the European Prospective Investigation into Cancer andNutrition (EPIC) that included 893 incident lung cancer cases and 1,748matched controls. Circulating levels of tryptophan and six of its metabolites were measured and evaluated in relation to lung cancer risk. Results: Tryptophan (P-trend = 2 Chi 10(-5)) and the kynurenine/ tryptophan ratio (KTR; P-trend 4 Chi 10(-5)) were associated with lung cancer risk overall after adjusting for established risk factors. The ORs comparing the fifth and first quintiles (OR5th (vs. 1st)) were 0.52 [ 95% confidence interval (CI), 0.37-0.74] for tryptophan and 1.74 (95% CI, 1.24-2.45) for KTR. After adjusting for plasma methionine (available fromprevious work, which was strongly correlated with tryptophan), the associations of tryptophan (adjusted P-trend 0.13) and KTR (P-trend = 0.009) were substantially attenuated. KTR was positively associated with squamous cell carcinoma, the OR5th vs. 1st being 2.83 (95% CI, 1.62-4.94, P-trend -3 Chi 10(-5)) that was only marginally affected by adjusting for methionine. Conclusions: This study indicates that biomarkers of tryptophan metabolism are associated with subsequent lung cancer risk. Although this result would seem consistent with the immune system having a role in lung cancer development, the overall associations were dependent on methionine, and further studies are warranted to further elucidate the importance of these metabolites in lung cancer etiology. Impact: This is the first prospective study investigating the tryptophan pathway in relation to lung cancer risk.
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| 4. |
- Fanidi, Anouar, et al.
(författare)
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Circulating vitamin D in relation to cancer incidence and survival of the head and neck and oesophagus in the EPIC cohort
- 2016
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- Experimental and epidemiological data suggest that vitamin D play a role in pathogenesis and progression of cancer, but prospective data on head and neck cancer (HNC) and oesophagus cancer are limited. The European Prospective Investigation into Cancer and Nutrition (EPIC) study recruited 385,747 participants with blood samples between 1992 and 2000. This analysis includes 497 case-control pairs of the head and neck and oesophagus, as well as 443 additional controls. Circulating 25(OH)D3 were measured in pre-diagnostic samples and evaluated in relation to HNC and oesophagus cancer risk and post-diagnosis all-cause mortality. After controlling for risk factors, a doubling of 25(OH)D3 was associated with 30% lower odds of HNC (OR 0.70, 95% confidence interval [95% CI] 0.56-0.88, Ptrend = 0.001). Subsequent analyses by anatomical sub-site indicated clear inverse associations with risk of larynx and hypopharynx cancer combined (OR 0.55, 95CI% 0.39-0.78) and oral cavity cancer (OR 0.60, 95CI% 0.42-0.87). Low 25(OH)D3 concentrations were also associated with higher risk of death from any cause among HNC cases. No clear association was seen with risk or survival for oesophageal cancer. Study participants with elevated circulating concentrations of 25(OH)D3 had decreased risk of HNC, as well as improved survival following diagnosis.
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| 5. |
- Johansson, Mattias, et al.
(författare)
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Serum B vitamin levels and risk of lung cancer
- 2010
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Ingår i: Journal of the American Medical Association (JAMA). - : American Medical Association. - 0098-7484 .- 1538-3598. ; 303:23, s. 2377-2385
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: B vitamins and factors related to 1-carbon metabolism help to maintain DNA integrity and regulate gene expression and may affect cancer risk. OBJECTIVE: To investigate if 1-carbon metabolism factors are associated with onset of lung cancer. DESIGN, SETTING, AND PARTICIPANTS: The European Prospective Investigation into Cancer and Nutrition (EPIC) recruited 519,978 participants from 10 countries between 1992 and 2000, of whom 385,747 donated blood. By 2006, 899 lung cancer cases were identified and 1770 control participants were individually matched by country, sex, date of birth, and date of blood collection. Serum levels were measured for 6 factors of 1-carbon metabolism and cotinine. MAIN OUTCOME MEASURE: Odds ratios (ORs) of lung cancer by serum levels of 4 B vitamins (B(2), B(6), folate [B(9)], and B(12)), methionine, and homocysteine. RESULTS: Within the entire EPIC cohort, the age-standardized incidence rates of lung cancer (standardized to the world population, aged 35-79 years) were 6.6, 44.9, and 156.1 per 100,000 person-years among never, former, and current smokers for men, respectively. The corresponding incidence rates for women were 7.1, 23.9, and 100.9 per 100,000 person-years, respectively. After accounting for smoking, a lower risk for lung cancer was seen for elevated serum levels of B(6) (fourth vs first quartile OR, 0.44; 95% confidence interval [CI], 0.33-0.60; P for trend <.000001), as well as for serum methionine (fourth vs first quartile OR, 0.52; 95% CI, 0.39-0.69; P for trend <.000001). Similar and consistent decreases in risk were observed in never, former, and current smokers, indicating that results were not due to confounding by smoking. The magnitude of risk was also constant with increasing length of follow-up, indicating that the associations were not explained by preclinical disease. A lower risk was also seen for serum folate (fourth vs first quartile OR, 0.68; 95% CI, 0.51-0.90; P for trend = .001), although this was apparent only for former and current smokers. When participants were classified by median levels of serum methionine and B(6), having above-median levels of both was associated with a lower lung cancer risk overall (OR, 0.41; 95% CI, 0.31-0.54), as well as separately among never (OR, 0.36; 95% CI, 0.18-0.72), former (OR, 0.51; 95% CI, 0.34-0.76), and current smokers (OR, 0.42; 95% CI, 0.27-0.65). CONCLUSION: Serum levels of vitamin B(6) and methionine were inversely associated with risk of lung cancer.
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| 6. |
- Morales-Berstein, Fernanda, et al.
(författare)
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Ultra-processed foods, adiposity and risk of head and neck cancer and oesophageal adenocarcinoma in the European Prospective Investigation into Cancer and Nutrition study : a mediation analysis
- 2024
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Ingår i: European Journal of Nutrition. - 1436-6215. ; 63:2, s. 377-396
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To investigate the role of adiposity in the associations between ultra-processed food (UPF) consumption and head and neck cancer (HNC) and oesophageal adenocarcinoma (OAC) in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.METHODS: Our study included 450,111 EPIC participants. We used Cox regressions to investigate the associations between the consumption of UPFs and HNC and OAC risk. A mediation analysis was performed to assess the role of body mass index (BMI) and waist-to-hip ratio (WHR) in these associations. In sensitivity analyses, we investigated accidental death as a negative control outcome.RESULTS: During a mean follow-up of 14.13 ± 3.98 years, 910 and 215 participants developed HNC and OAC, respectively. A 10% g/d higher consumption of UPFs was associated with an increased risk of HNC (hazard ratio [HR] = 1.23, 95% confidence interval [CI] 1.14-1.34) and OAC (HR = 1.24, 95% CI 1.05-1.47). WHR mediated 5% (95% CI 3-10%) of the association between the consumption of UPFs and HNC risk, while BMI and WHR, respectively, mediated 13% (95% CI 6-53%) and 15% (95% CI 8-72%) of the association between the consumption of UPFs and OAC risk. UPF consumption was positively associated with accidental death in the negative control analysis.CONCLUSIONS: We reaffirmed that higher UPF consumption is associated with greater risk of HNC and OAC in EPIC. The proportion mediated via adiposity was small. Further research is required to investigate other mechanisms that may be at play (if there is indeed any causal effect of UPF consumption on these cancers).
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| 7. |
- Timofeeva, Maria N, et al.
(författare)
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Genetic polymorphisms in 15q25 and 19q13 loci, cotinine levels, and risk of lung cancer in EPIC
- 2011
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - 1055-9965 .- 1538-7755. ; 20:10, s. 2250-2261
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Tidskriftsartikel (refereegranskat)abstract
- Backgrounds: Multiple polymorphisms affecting smoking behavior have been identified through genome-wide association studies. Circulating levels of the nicotine metabolite cotinine is a marker of recent smoking exposure. Hence, genetic variants influencing smoking behavior are expected to be associated with cotinine levels.METHODS: We conducted an analysis in a lung cancer case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. We investigated the effects of single-nucleotide polymorphisms (SNP) previously associated with smoking behavior on (i) circulating cotinine and (ii) lung cancer risk. A total of 894 cases and 1,805 controls were analyzed for cotinine and genotyped for 10 polymorphisms on 7p14, 8p11, 10q23, 15q25, and 19q13.RESULTS: Two variants in the nicotinic acetylcholine receptor subunit genes CHRNA5 and CHRNA3 on 15q25, rs16969968 and rs578776, were associated with cotinine (P = 0.001 and 0.03, respectively) in current smokers and with lung cancer risk (P < 0.001 and P = 0.001, respectively). Two 19q13 variants, rs7937 and rs4105144, were associated with increased cotinine (P = 0.003 and P < 0.001, respectively) but decreased lung cancer risk (P = 0.01 for both, after adjusting for cotinine). Variants in 7p14, 8p11, and 10q23 were not associated with cotinine or lung cancer risk.CONCLUSIONS: 15q25 and 19q13 SNPs were associated with circulating cotinine. The directions of association for 15q25 variants with cotinine were in accordance with that expected of lung cancer risk, whereas SNPs on 19q13 displayed contrasting associations of cotinine and lung cancer that require further investigation.Impact: This study is the largest to date investigating the effects of polymorphisms affecting smoking behavior on lung cancer risk using circulating cotinine measures as proxies for recent smoking behavior. Cancer Epidemiol Biomarkers Prev; ©2011 AACR.
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