title: Relationship between serum levels of insulin-like growth factors and subsequent risk of cancer mortality: findings from a nested case-control study within the Japan Collaborative Cohort Study.
abstract: BACKGROUND
  We investigated the association between serum levels of IGF-I, IGF-II, and IGFBP-3 and the subsequent risk of cancer mortality.
  
  
  METHODS
  Our case-control study examined samples from 914 cancer deaths and their 2739 matched controls within the Japan Collaborative Cohort Study. Blood samples were obtained at the baseline and stored at -80 degrees C until analysis for IGF-I, IGF-II, and IGFBP-3 levels. The conditional logistic model was used to estimate odds ratios (ORs) for cancer mortality associated with these serum levels.
  
  
  RESULTS
  The adjusted ORs for IGF-I quartiles ranged from 0.81 to 0.96 but were not significant. The adjusted ORs and 95% confidence interval (CI) for the second, third, and fourth IGF-II quartiles were 0.64 (95% CI: 0.52-0.79), 0.71 (95% CI: 0.58-0.88), and 0.73 (95% CI: 0.59-0.91), respectively, while those for the respective IGFBP-3 quartiles were 0.77 (95% CI: 0.63-0.96), 0.75 (95% CI: 0.60-0.94), and 0.71 (95% CI: 0.56-0.90). In the model of IGF-I, and IGF-II additionally adjusted for IGFBP-3, the associations of high IGFs levels were similar as observed in the above models, while the association of IGFBP-3 shifted into non-significance after adjusting for IGF-II.
  
  
  CONCLUSIONS
  An increased level of IGF-II was significantly associated with decreased risk of cancer mortality, whereas the association between IGF-I and all cancer mortality was not significant. The inverse association of IGFBP-3 level with all cancer mortality was affected when adjusting for IGF-II levels, shifting from significant to non-significant. Confirmation of these results from further cohort studies may aid in identifying the potential association between these molecules and the risk of cancer among the general Japanese population.
authors.affiliation: Department of Preventive Medicine and Community Health, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu-shi, Japan. ptrminh@med.uoeh-u.ac.jp
authors.forename: Truong-Minh
authors.initials: TM
authors.lastname: Pham
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Fujino
authors.forename: Kei
authors.initials: K
authors.lastname: Nakachi
authors.forename: Koji
authors.initials: K
authors.lastname: Suzuki
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ito
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Inaba
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tajima
authors.forename: Akiko
authors.initials: A
authors.lastname: Tamakoshi
authors.forename: Takesumi
authors.initials: T
authors.lastname: Yoshimura
mesh_terms: D016022:Case-Control Studies; D015331:Cohort Studies; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007335:Insulin-Like Growth Factor II / Q000378:metabolism*; D007564:Japan / Q000453:epidemiology; D009369:Neoplasms / Q000097:blood / Q000401:mortality*; D016017:Odds Ratio; D012307:Risk Factors
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II