1. Circulating free insulin-like growth factor-I and prostate cancer: a case-control study nested in the European prospective investigation into cancer and nutrition.
- Author
-
Cheng TS, Noor U, Watts E, Pollak M, Wang Y, McKay J, Atkins J, Masala G, Sánchez MJ, Agudo A, Castilla J, Aune D, Colorado-Yohar SM, Manfredi L, Gunter MJ, Pala V, Josefsson A, Key TJ, Smith-Byrne K, and Travis RC
- Subjects
- Humans, Male, Middle Aged, Case-Control Studies, Prospective Studies, Europe epidemiology, Aged, Risk Factors, Biomarkers, Tumor blood, Insulin-Like Peptides, Prostatic Neoplasms blood, Prostatic Neoplasms epidemiology, Prostatic Neoplasms pathology, Insulin-Like Growth Factor I metabolism, Insulin-Like Growth Factor I analysis
- Abstract
Background: Circulating total insulin-like growth factor-I (IGF-I) is an established risk factor for prostate cancer. However, only a small proportion of circulating IGF-I is free or readily dissociable from IGF-binding proteins (its bioavailable form), and few studies have investigated the association of circulating free IGF-I with prostate cancer risk., Methods: We analyzed data from 767 prostate cancer cases and 767 matched controls nested within the European Prospective Investigation into Cancer and Nutrition cohort, with an average of 14-years (interquartile range = 2.9) follow-up. Matching variables were study center, length of follow-up, age, and time of day and fasting duration at blood collection. Circulating free IGF-I concentration was measured in serum samples collected at recruitment visit (mean age 55 years old; standard deviation = 7.1) using an enzyme-linked immunosorbent assay (ELISA). Conditional logistic regressions were performed to examine the associations of free IGF-I with risk of prostate cancer overall and subdivided by time to diagnosis (≤ 14 and > 14 years), and tumor characteristics., Results: Circulating free IGF-I concentrations (in fourths and as a continuous variable) were not associated with prostate cancer risk overall (odds ratio [OR] = 1.00 per 0.1 nmol/L increment, 95% CI: 0.99, 1.02) or by time to diagnosis, or with prostate cancer subtypes, including tumor stage and histological grade., Conclusions: Estimated circulating free IGF-I was not associated with prostate cancer risk. Further research may consider other assay methods that estimate bioavailable IGF-I to provide more insight into the well-substantiated association between circulating total IGF-I and subsequent prostate cancer risk., (© 2024. The Author(s).)
- Published
- 2024
- Full Text
- View/download PDF