title: Circulating vitamin D metabolites, polymorphism in vitamin D receptor, and colorectal adenoma risk.
abstract: OBJECTIVE
  Vitamin D is a potential agent for the prevention of colorectal cancer possibly through mechanisms mediated by the vitamin D receptor (VDR). We investigated the association of circulating vitamin D metabolites and a genetic variant of the VDR gene with advanced colorectal adenoma, a precursor lesion of colorectal cancer.
  
  
  METHODS
  Cases with advanced adenoma of the distal large bowel and gender- and ethnicity-matched controls with a negative sigmoidoscopy were randomly selected from participants in the Prostate, Lung, Colorectal and Ovarian Cancer Screening trial. Genotype analysis of the VDR TaqI polymorphism was completed on 763 cases and 774 controls. Serum levels of 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)(2)D] were measured in a subset of 394 cases and 397 controls.
  
  
  RESULTS
  Serum levels of 25(OH)D were inversely associated with advanced adenoma risk in women but not in men. Comparing those in the highest quintile with those in the lowest quintile, the risk for advanced adenoma decreased by 73% in women [odds ratio (OR) = 0.27, 95% confidence interval (95% CI) = 0.11-0.69; P for trend = 0.0002], while the risk did not decrease in men (OR = 1.10, 95% CI = 0.60-2.05; P for trend = 0.85). In women, 25(OH)D levels were significantly higher in current users of hormone replacement therapy (HRT) than in former or never HRT users. Neither serum 1,25(OH)(2)D nor VDR TaqI genotype was associated with advanced adenoma risk.
  
  
  CONCLUSIONS
  Higher serum 25(OH)D levels were associated with decreased adenoma risk. Serum 1,25(OH)(2)D and VDR TaqI genotype were not associated with adenoma risk.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH/DHHS, 6120 Executive Boulevard, EPS 3024, Rockville, MD 20852, USA. petersu@mail.nih.gov
authors.forename: Ulrike
authors.initials: U
authors.lastname: Peters
authors.forename: Richard B
authors.initials: RB
authors.lastname: Hayes
authors.forename: Nilanjan
authors.initials: N
authors.lastname: Chatterjee
authors.forename: Wen
authors.initials: W
authors.lastname: Shao
authors.forename: Robert E
authors.initials: RE
authors.lastname: Schoen
authors.forename: Paul
authors.initials: P
authors.lastname: Pinsky
authors.forename: Bruce W
authors.initials: BW
authors.lastname: Hollis
authors.forename: Katherine A
authors.initials: KA
authors.lastname: McGlynn
mesh_terms: D000236:Adenoma / Q000097:blood / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics; D000368:Aged; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D011897:Random Allocation; D018167:Receptors, Calcitriol / Q000235:genetics*; D012307:Risk Factors; D012737:Sex Factors; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology; D014807:Vitamin D / Q000097:blood*
chemical_list: D018167:Receptors, Calcitriol; D014807:Vitamin D