Gender difference in the association of insulin and the insulin-like growth factor axis with colorectal neoplasia

Int J Obes (Lond). 2012 Mar;36(3):440-7. doi: 10.1038/ijo.2011.114. Epub 2011 Jun 14.

Abstract

Objective: Accumulating evidence has implicated insulin and the insulin-like growth factor (IGF) axis in colorectal carcinogenesis. Of interest, adiposity is likely to impose a greater risk on men than on women, which indicates that the association of insulin and the IGF axis with colorectal neoplasia may differ by gender. However, epidemiological evidence for this possible gender difference is limited to date.

Methods: We measured plasma concentrations of C-peptide, IGF-I and IGF-binding proteins (IGFBPs) 1 and 3 in 1520 healthy volunteer examinees who underwent total colonoscopy between February 2004 and February 2005, and cross-sectionally investigated the association of these biomarkers with colorectal adenoma by gender. An unconditional logistic regression model was used to estimate odds ratios (ORs) and their 95% confidence intervals (CIs) for colorectal adenoma after adjustment for potential confounders.

Results: We observed a positive association of C-peptide and IGF-I (P (trend)<0.001 and 0.02, respectively) and an inverse association of IGFBP-1 (P (trend)=0.002) with colorectal adenoma in men. Adjusted ORs of colorectal adenoma for the highest compared with the lowest quartile were also statistically significant for C-peptide (OR: 2.62, 95% CI: 1.71-4.01), IGF-I (OR: 1.63, 95% CI: 1.08-2.46) and IGFBP-1 (OR: 0.49, 95% CI: 0.32-0.75). In contrast, no measurable association was seen in women. Corresponding ORs for C-peptide, IGF-I and IGFBP-1 were 0.98 (95% CI: 0.56-1.71), 0.79 (95% CI: 0.44-1.43) and 1.05 (95% CI: 0.60-1.86), respectively. The gender difference was statistically significant for C-peptide (P (interaction)=0.03) and marginally significant for IGF-I and IGFBP-1 (P (interaction)=0.14 and 0.12, respectively).

Conclusion: Our observations suggest that insulin and the IGF axis act differently by gender in colorectal carcinogenesis, at least in its early stage. The findings of this study further our understanding of the complexities of the gender difference in the association between adiposity and colorectal neoplasia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoma / blood*
  • Adenoma / epidemiology
  • Adenoma / etiology
  • Adult
  • Aged
  • Asian Continental Ancestry Group
  • C-Peptide / blood*
  • Case-Control Studies
  • Cell Transformation, Neoplastic
  • Colonoscopy / statistics & numerical data
  • Colorectal Neoplasms / blood*
  • Colorectal Neoplasms / epidemiology
  • Colorectal Neoplasms / etiology
  • Female
  • Humans
  • Insulin / metabolism*
  • Insulin-Like Growth Factor Binding Protein 1 / blood*
  • Insulin-Like Growth Factor I / metabolism*
  • Life Style
  • Logistic Models
  • Male
  • Middle Aged
  • Obesity / blood*
  • Obesity / complications
  • Obesity / epidemiology
  • Odds Ratio
  • Risk Factors
  • Sex Distribution
  • Sex Factors
  • Surveys and Questionnaires

Substances

  • C-Peptide
  • Insulin
  • Insulin-Like Growth Factor Binding Protein 1
  • Insulin-Like Growth Factor I