Genetic and dietary determinants of insulin-like growth factor (IGF)-1 and IGF binding protein (BP)-3 levels among Chinese women

PLoS One. 2014 Oct 6;9(10):e108934. doi: 10.1371/journal.pone.0108934. eCollection 2014.

Abstract

Background: Higher insulin-like growth factor (IGF)-1 and lower IGF binding protein (BP)-3 levels have been associated with higher commoncancer risk, including breast cancer. Dietary factors, genetic polymorphisms, and the combination of both may influence circulating IGF-1 and IGFBP-3 serum concentrations.

Methods: From September 2011 to July 2012, we collected demographic, reproductive and dietary data on 143 women (≥ 40 years). We genotyped IGF-1 rs1520220 and IGFBP-3 rs2854744 and measured circulating IGF-1 and IGFBP-3 levels in serum. Covariance analyses were used to estimate the associations of serum levels of IGF-1 and IGFBP-3, and the molar ratio of IGF-1 to IGFBP-3 with IGF-1 rs1520220 and IGFBP-3 rs2854744 genotypes. We subsequently assessed the combined influence of genetics and diet (daily intake of protein, fat and soy isoflavones) on IGF-1 and IGFBP-3 levels.

Results: Among women aged less than 50 years, circulating IGF-1 serum levels were significantly lower for those with CC genotype for IGF-1 rs1520220 than levels for those with the GC or GG genotypes (in recessive model: P = 0.007).In gene-diet analyses among these women, we found carrying CC genotype for IGF-1 rs1520220 and high soy isoflavone intake tend to be associated with lower circulating IGF-1 levels synthetically (P = 0.002). Women with GG or GC genotypes for IGF-1 rs1520220 and with low intake of soy isoflavones had the highest levels of circulating IGF-1 (geometric mean [95% CI]: 195 [37, 1021] µg/L). Comparatively, women with both the CC genotype and high soy intake had the lowest levels of circulating IGF-1 (geometric mean [95% CI]: 120 [38,378] µg/L).

Conclusions: IGF-1 serum levels are significantly lower among women with the CC genotype for IGF-1-rs1520220. High soy isoflavone intake may interact with carrying CC genotype for IGF-1-rs1520220 to lower women's serum IGF-1 levels more.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Asian People / genetics*
  • China
  • Demography
  • Diet*
  • Female
  • Humans
  • Insulin-Like Growth Factor Binding Protein 3 / blood
  • Insulin-Like Growth Factor Binding Protein 3 / genetics*
  • Insulin-Like Growth Factor I / genetics*
  • Isoflavones / pharmacology
  • Middle Aged
  • Polymorphism, Single Nucleotide
  • Reproduction

Substances

  • Insulin-Like Growth Factor Binding Protein 3
  • Isoflavones
  • Insulin-Like Growth Factor I

Grants and funding

This work was funded by the Ministry of Education Fundamental Research Foundation for Central Universities, P.R. China (grant no. 2010SCU21001). The URL of funder's website is http://st.scu.edu.cn/index.aspx. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.