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- Jenab, Mazda, et al.
(författare)
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Association between pre-diagnostic circulating vitamin D concentration and risk of colorectal cancer in European populations : a nested case-control study
- 2010
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Ingår i: BMJ. British Medical Journal. - : BMJ Publishing Group. - 0959-8146 .- 0959-535X. ; 340, s. b5500-
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To examine the association between pre-diagnostic circulating vitamin D concentration, dietary intake of vitamin D and calcium, and the risk of colorectal cancer in European populations. DESIGN: Nested case-control study. Setting The study was conducted within the EPIC study, a cohort of more than 520 000 participants from 10 western European countries. PARTICIPANTS: 1248 cases of incident colorectal cancer, which developed after enrolment into the cohort, were matched to 1248 controls MAIN OUTCOME MEASURES: Circulating vitamin D concentration (25-hydroxy-vitamin-D, 25-(OH)D) was measured by enzyme immunoassay. Dietary and lifestyle data were obtained from questionnaires. Incidence rate ratios and 95% confidence intervals for the risk of colorectal cancer by 25-(OH)D concentration and levels of dietary calcium and vitamin D intake were estimated from multivariate conditional logistic regression models, with adjustment for potential dietary and other confounders. RESULTS: 25-(OH)D concentration showed a strong inverse linear dose-response association with risk of colorectal cancer (P for trend <0.001). Compared with a pre-defined mid-level concentration of 25-(OH)D (50.0-75.0 nmol/l), lower levels were associated with higher colorectal cancer risk (<25.0 nmol/l: incidence rate ratio 1.32 (95% confidence interval 0.87 to 2.01); 25.0-49.9 nmol/l: 1.28 (1.05 to 1.56), and higher concentrations associated with lower risk (75.0-99.9 nmol/l: 0.88 (0.68 to 1.13); >or=100.0 nmol/l: 0.77 (0.56 to 1.06)). In analyses by quintile of 25-(OH)D concentration, patients in the highest quintile had a 40% lower risk of colorectal cancer than did those in the lowest quintile (P<0.001). Subgroup analyses showed a strong association for colon but not rectal cancer (P for heterogeneity=0.048). Greater dietary intake of calcium was associated with a lower colorectal cancer risk. Dietary vitamin D was not associated with disease risk. Findings did not vary by sex and were not altered by corrections for season or month of blood donation. CONCLUSIONS: The results of this large observational study indicate a strong inverse association between levels of pre-diagnostic 25-(OH)D concentration and risk of colorectal cancer in western European populations. Further randomised trials are needed to assess whether increases in circulating 25-(OH)D concentration can effectively decrease the risk of colorectal cancer.
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| 2. |
- Fedirko, Veronika, et al.
(författare)
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Prediagnostic 25-Hydroxyvitamin D, VDR and CASR polymorphisms, and survival in patients with colorectal cancer in Western European populations
- 2012
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - 1055-9965 .- 1538-7755. ; 21:4, s. 582-593
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Tidskriftsartikel (refereegranskat)abstract
- Background: Individuals with higher blood 25-hydroxyvitamin D [25(OH)D] levels have a lower risk of developing colorectal cancer (CRC), but the influence of 25(OH)D on mortality after CRC diagnosis is unknown.Methods: The association between prediagnostic 25(OH)D levels and CRC-specific (N ¼ 444) and overall mortality (N ¼ 541) was prospectively examined among 1,202 participants diagnosed with CRC between 1992 and 2003 in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.Multivariable Cox proportional hazards models were used to calculate HRs and corresponding 95% CIs according to 25(OH)D quintiles and genetic variation within the VDR and CASR genes. Potential dietary, lifestyle, and metabolic effect modifiers were also investigated.Results: There were 541 deaths, 444 (82%) due to CRC. Mean follow-up was 73 months. In multivariable analysis, higher 25(OH)D levels were associated with a statistically significant reduction in CRC-specific (Ptrend ¼ 0.04) and overall mortality (Ptrend ¼ 0.01). Participants with 25(OH)D levels in the highest quintile had an adjusted HR of 0.69 (95% CI: 0.50–0.93) for CRC-specific mortality and 0.67 (95% CI: 0.50–0.88) for overall mortality, compared with the lowest quintile. Except for a possible interaction by prediagnostic dietary calcium intake (Pinteraction ¼ 0.01), no other potential modifying factors related to CRC survival were noted. The VDR (FokI and BsmI) and CASR (rs1801725) genotypes were not associated with survival.Conclusions: High prediagnostic 25(OH)D levels are associated with improved survival of patients with CRC. Impact: Our findings may stimulate further research directed at investigating the effects of blood vitamin D levels before, at, and after CRC diagnosis on outcomes in CRC patients.
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| 3. |
- Jenab, Mazda, et al.
(författare)
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Vitamin D receptor and Calcium sensing receptor Polymorphisms and the risk of Colorectal Cancer in European populations
- 2009
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research. - 1055-9965 .- 1538-7755. ; 18, s. 2485-2491
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Tidskriftsartikel (refereegranskat)abstract
- Increased levels of vitamin D and calcium may play a protective role in colorectal cancer (CRC) risk. It has been suggested that these effects may be mediated by genetic variants of the vitamin D receptor (VDR) and the calcium sensing receptor (CASR). However, current epidemiologic evidence from European populations for a role of these genes in CRC risk is scarce. In addition, it is not clear whether these genes may modulate CRC risk independently or by interaction with blood vitamin D concentration and level of dietary calcium intake. A case-control study was conducted nested within the European Prospective Investigation into Cancer and Nutrition. CRC cases (1,248) were identified and matched to 1,248 control subjects. Genotyping for the VDR (BsmI: rs1544410; Fok1: rs2228570) and CASR (rs1801725) genes was done by Taqman, and serum vitamin D (25OHD) concentrations were measured. Conditional logistic regression was used to estimate the incidence rate ratio (RR). Compared with the wild-type bb, the BB genotype of the VDR BsmI polymorphism was associated with a reduced risk of CRC [RR, 0.76; 95% confidence interval (CI), 0.59-0.98). The association was observed for colon cancer (RR, 0.69; 95% CI, 0.45-0.95) but not rectal cancer (RR, 0.97; 95% CI, 0.62-1.49). The Fok1 and CASR genotypes were not associated with CRC risk in this study. No interactions were noted for any of the polymorphisms with serum 25OHD concentration or level of dietary calcium. These results confirm a role for the BsmI polymorphism of the VDR gene in CRC risk, independent of serum 25OHD concentration and dietary calcium intake. (Cancer Epidemiol Biomarkers Prev 2009;18(9):2485-91).
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