| 1. |
- Bakker, Marije F., et al.
(författare)
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Plasma carotenoids, vitamin C, tocopherols, and retinol and the risk of breast cancer in the European Prospective Investigation into Cancer and Nutrition cohort
- 2016
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Ingår i: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 103:2, s. 454-464
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Tidskriftsartikel (refereegranskat)abstract
- Background: Carotenoids and vitamin C are thought to be associated with reduced cancer risk because of their antioxidative capacity.Objective: This study evaluated the associations of plasma carotenoid, retinol, tocopherol, and vitamin C concentrations and risk of breast cancer.Design: In a nested case-control study within the European Prospective Investigation into Cancer and Nutrition cohort, 1502 female incident breast cancer cases were included, with an oversampling of premenopausal (n = 582) and estrogen receptor-negative (ER-) cases (n = 462). Controls (n = 1502) were individually matched to cases by using incidence density sampling. Prediagnostic samples were analyzed for alpha-carotene, beta-carotene, lycopene, lutein, zeaxanthin, beta-cryptoxanthin, retinol, alpha-tocopherol, gamma-tocopherol, and 454 vitamin C. Breast cancer risk was computed according to hormone receptor status and age at diagnosis (proxy for menopausal status) by using conditional logistic regression and was further stratified by smoking status, alcohol consumption, and body mass index (BMI). All statistical tests were 2-sided.Results: In quintile 5 compared with quintile 1, alpha-carotene (OR: 0.61; 95% CI: 0.39, 0.98) and beta-carotene (OR: 0.41; 95% CI: 0.26, 0.65) were inversely associated with risk of ER- breast tumors. The other analytes were not statistically associated with ER- breast cancer. For estrogen receptor-positive (ER+) tumors, no statistically significant associations were found. The test for heterogeneity between ER- and ER+ tumors was statistically significant only for beta-carotene (P-heterogeneity = 0.03). A higher risk of breast cancer was found for retinol in relation to ER-/progesterone receptor-negative tumors (OR: 2.37; 95% CI: 1.20, 4.67; P-heterogeneity with ER+/progesterone receptor positive = 0.06). We observed no statistically significant interaction between smoking, alcohol, or BMI and all investigated plasma analytes (based on tertile distribution).Conclusion: Our results indicate that higher concentrations of plasma beta-carotene and alpha-carotene are associated with lower breast cancer risk of ER tumors.
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| 2. |
- Ros, Martine M., et al.
(författare)
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Plasma carotenoids and vitamin C concentrations and risk of urothelial cell carcinoma in the European Prospective Investigation into Cancer and Nutrition
- 2012
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Ingår i: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 96:4, s. 902-910
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Tidskriftsartikel (refereegranskat)abstract
- Background: Published associations between dietary carotenoids and vitamin C and bladder cancer risk are inconsistent. Biomarkers may provide more accurate measures of nutrient status. Objective: We investigated the association between plasma carotenoids and vitamin C and risk of urothelial cell carcinoma (UCC) in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition. Design: A total of 856 patients with newly diagnosed UCC were matched with 856 cohort members by sex, age at baseline, study center, date and time of blood collection, and fasting status. Plasma carotenoids (alpha- and beta-carotene, beta-cryptoxanthin, lycopene, lutein, and zeaxanthin) were measured by using reverse-phase HPLC, and plasma vitamin C was measured by using a colorimetric assay. Incidence rate ratios (IRRs) were estimated by using conditional logistic regression with adjustment for smoking status, duration, and intensity. Results: UCC risk decreased with higher concentrations of the sum of plasma carotenoids (IRR for the highest compared with the lowest quartile: 0.64; 95% CI: 0.44, 0.93; P-trend = 0.04). Plasma beta-carotene was inversely associated with aggressive UCC (IRR: 0.51; 95% CI: 0.30, 0.88; P-trend = 0.02). Plasma lutein was inversely associated with risk of nonaggressive UCC (IRR: 0.56; 95% CI: 0.32, 0.98; P-trend = 0.05). No association was observed between plasma vitamin C and risk of UCC. Conclusions: Although residual confounding by smoking or other factors cannot be excluded, higher concentrations of plasma carotenoids may reduce risk of UCC, in particular aggressive UCC. Plasma lutein may reduce risk of nonaggressive UCC.
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| 3. |
- Aleksandrova, Krasimira, et al.
(författare)
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Adiposity, mediating biomarkers and risk of colon cancer in the European prospective investigation into cancer and nutrition study
- 2014
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Ingår i: International Journal of Cancer. - : Wiley-Blackwell. - 0020-7136 .- 1097-0215. ; 134:3, s. 612-621
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Tidskriftsartikel (refereegranskat)abstract
- Adiposity is a risk factor for colon cancer, but underlying mechanisms are not well understood. We evaluated the extent to which 11 biomarkers with inflammatory and metabolic actions mediate the association of adiposity measures, waist circumference (WC) and body mass index (BMI), with colon cancer in men and women. We analyzed data from a prospective nested case-control study among 662 incident colon cancer cases matched within risk sets to 662 controls. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression. The percent effect change and corresponding CIs were estimated after adjusting for biomarkers shown to be associated with colon cancer risk. After multivariable adjustment, WC was associated with colon cancer risk in men (top vs. bottom tertile RR 1.68, 95% CI 1.06-2.65; ptrend = 0.02) and in women (RR 1.67, 95% CI 1.09-2.56; ptrend = 0.03). BMI was associated with risk only in men. The association of WC with colon cancer was accounted mostly for by three biomarkers, high-density lipoprotein cholesterol, non-high-molecular-weight adiponectin and soluble leptin receptor, which in combination explained 46% (95% CI 37-57%) of the association in men and 50% (95% CI 40-65%) of the association in women. Similar results were observed for the associations with BMI in men. These data suggest that alterations in levels of these metabolic biomarkers may represent a primary mechanism of action in the relation of adiposity with colon cancer. Further studies are warranted to determine whether altering their concentrations may reduce colon cancer risk.
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