title: Dietary and supplemental intake of one-carbon nutrients and the risk of type I and type II endometrial cancer: a prospective cohort study.
abstract: BACKGROUND
  Type I and II endometrial cancer are biologically and clinically distinct, with type II cancers having a high frequency of p53 mutations and an association with chromosomal instability. This raises the hypothesis that one-carbon nutrients (folate, methionine, and the enzymic cofactors vitamins B2, B6, and B12), which mediate chromosomal stability and DNA methylation, may be protective for type II but not type I endometrial cancer.
  
  
  METHODS
  Using a prospective cohort of 23 356 postmenopausal women followed 20 years, we estimated the relative risks (RRs) of type I (N = 471) and II (N = 71) endometrial cancers according to intake of one-carbon nutrients, adjusting for confounders.
  
  
  RESULTS
  No associations were observed between dietary or supplemental intake of any one-carbon nutrient and risk of type I cancer. For type II cancer, positive associations were due to supplemental, rather than dietary, intake of these nutrients: supplemental folate (RR = 1.80 for >228.6 versus 0 μg/day; P trend = 0.027) and vitamins B2 (RR = 1.94 for >1.70 versus 0 mg/day; P trend = 0.011), B6 (RR = 2.08 for >2.00 versus 0 mg/day; P trend = 0.012), and B12 (RR = 2.10 for >3.43 versus 0 μg/day; P trend = 0.0060).
  
  
  CONCLUSIONS
  Contrary to our hypothesis, use of supplements containing folate and vitamins B2, B6, and B12 was associated with an increased risk of type II endometrial cancer.
authors.affiliation: Department of Obstetrics and Gynecology, Division of Gynecologic Surgery.
authors.forename: S
authors.initials: S
authors.lastname: Uccella
authors.affiliation: Department of Obstetrics and Gynecology, Division of Gynecologic Surgery.
authors.forename: A
authors.initials: A
authors.lastname: Mariani
authors.affiliation: Department of Health Sciences Research, Division of Biomedical Statistics and Informatics, Mayo Clinic College of Medicine, Rochester.
authors.forename: A H
authors.initials: AH
authors.lastname: Wang
authors.affiliation: Department of Health Sciences Research, Division of Biomedical Statistics and Informatics, Mayo Clinic College of Medicine, Rochester.
authors.forename: R A
authors.initials: RA
authors.lastname: Vierkant
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis.
authors.forename: K
authors.initials: K
authors.lastname: Robien
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis.
authors.forename: K E
authors.initials: KE
authors.lastname: Anderson
authors.affiliation: Department of Health Sciences Research, Division of Epidemiology, Mayo Clinic College of Medicine, Rochester, USA. Electronic address: cerhan.james@mayo.edu.
authors.forename: J R
authors.initials: JR
authors.lastname: Cerhan
mesh_terms: D000368:Aged; D043171:Chromosomal Instability; D015331:Cohort Studies; D019175:DNA Methylation; D004032:Diet / Q000706:statistics & numerical data*; D019587:Dietary Supplements / Q000706:statistics & numerical data*; D016889:Endometrial Neoplasms / Q000453:epidemiology* / Q000235:genetics; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage; D006801:Humans; D008715:Methionine / Q000008:administration & dosage; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D011446:Prospective Studies; D014815:Vitamins / Q000008:administration & dosage
chemical_list: D014815:Vitamins; D005492:Folic Acid; D008715:Methionine