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- de Vogel, Stefan, et al.
(författare)
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Biomarkers related to one-carbon metabolism as potential risk factors for distal colorectal adenomas
- 2011
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research. - 1055-9965 .- 1538-7755. ; 20:8, s. 1726-1735
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Efficient one-carbon metabolism, which requires adequate supply of methyl group donors and B-vitamins, may protect against colorectal carcinogenesis. However, plasma folate and vitamins B2 and B12 have inconsistently been associated with colorectal cancer risk, and there have been no previous studies relating plasma concentrations of methionine, choline, and betaine to this outcome.METHODS: This study comprised 10,601 individuals, 50 to 64 years of age, participating in the Norwegian Colorectal Cancer Prevention (NORCCAP) screening study. Using logistic regression analyses, we crosssectionally investigated associations between distal colorectal adenoma occurrence-potential precursor lesions of colorectal carcinomas-and plasma concentrations of methyl group donors and B-vitamins, and polymorphisms of genes related to one-carbon metabolism.RESULTS: Screening revealed 1,809 subjects (17.1%) with at least one adenoma. The occurrence of high-risk adenomas (observed in 421 subjects) was inversely associated with plasma concentrations of methionine (highest versus lowest quartile: odds ratio (OR) = 0.61; 95% confidence interval (CI) = 0.45-0.83), betaine: OR = 0.74; 95% CI = 0.54-1.02, the vitamin B2 form flavin-mononucleotide (FMN): OR = 0.65; 95% CI = 0.49-0.88, and the vitamin B6 form pyridoxal 5'-phosphate (PLP): OR = 0.69; 95% CI = 0.51-0.95, but not with folate, choline, vitamin B12 concentrations, or with the studied polymorphisms. High methionine concentration in combination with high vitamin B2 or B6 concentrations was associated with lower occurrence of high-risk adenomas compared with these factors individually.CONCLUSIONS: High plasma concentrations of methionine and betaine, and vitamins B2 and B6 may reduce risk of developing colorectal adenomas.IMPACT: In addition to B-vitamins, methyl group donors such as methionine and betaine may play a role in colorectal carcinogenesis.
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| 2. |
- Price, Alison J, et al.
(författare)
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Circulating Folate and Vitamin B12 and Risk of Prostate Cancer : A Collaborative Analysis of Individual Participant Data from Six Cohorts Including 6875 Cases and 8104 Controls.
- 2016
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Ingår i: European Urology. - : Elsevier BV. - 0302-2838 .- 1873-7560. ; 70:6, s. 941-951
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Folate and vitamin B12 are essential for maintaining DNA integrity and may influence prostate cancer (PCa) risk, but the association with clinically relevant, advanced stage, and high-grade disease is unclear.OBJECTIVE: To investigate the associations between circulating folate and vitamin B12 concentrations and risk of PCa overall and by disease stage and grade.DESIGN, SETTING, AND PARTICIPANTS: A study was performed with a nested case-control design based on individual participant data from six cohort studies including 6875 cases and 8104 controls; blood collection from 1981 to 2008, and an average follow-up of 8.9 yr (standard deviation 7.3). Odds ratios (ORs) of incident PCa by study-specific fifths of circulating folate and vitamin B12 were calculated using multivariable adjusted conditional logistic regression.OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Incident PCa and subtype by stage and grade.RESULTS AND LIMITATIONS: Higher folate and vitamin B12 concentrations were associated with a small increase in risk of PCa (ORs for the top vs bottom fifths were 1.13 [95% confidence interval (CI), 1.02-1.26], ptrend=0.018, for folate and 1.12 [95% CI, 1.01-1.25], ptrend=0.017, for vitamin B12), with no evidence of heterogeneity between studies. The association with folate varied by tumour grade (pheterogeneity<0.001); higher folate concentration was associated with an elevated risk of high-grade disease (OR for the top vs bottom fifth: 2.30 [95% CI, 1.28-4.12]; ptrend=0.001), with no association for low-grade disease. There was no evidence of heterogeneity in the association of folate with risk by stage or of vitamin B12 with risk by stage or grade of disease (pheterogeneity>0.05). Use of single blood-sample measurements of folate and B12 concentrations is a limitation.CONCLUSIONS: The association between higher folate concentration and risk of high-grade disease, not evident for low-grade disease, suggests a possible role for folate in the progression of clinically relevant PCa and warrants further investigation.PATIENT SUMMARY: Folate, a vitamin obtained from foods and supplements, is important for maintaining cell health. In this study, however, men with higher blood folate levels were at greater risk of high-grade (more aggressive) prostate cancer compared with men with lower folate levels. Further research is needed to investigate the possible role of folate in the progression of this disease.
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