Plasma Insulin-Like Growth Factor-I, Insulin-Like Growth Factor-Binding Proteins, and Prostate Cancer Risk: a Prospective Study

• Published in: JNCI : Journal of the National Cancer Institute Vol. 92; no. 23; pp. 1910 - 1917
• Main Authors: Stattin, Pär, Bylund, Annika, Rinaldi, Sabina, Biessy, Carine, Déchaud, Henri, Stenman, Ulf-Håkan, Egevad, Lars, Riboli, Elio, Hallmans, Göran, Kaaks, Rudolf
• Format: Journal Article
• Language: English
• Published: Cary, NC Oxford University Press 06.12.2000
• Subjects: Age Factors; Aged; Biological and medical sciences; Case-Control Studies; Cross-Sectional Studies; Humans; Insulin - blood; Insulin-Like Growth Factor Binding Protein 1 - blood; Insulin-Like Growth Factor Binding Protein 2 - blood; Insulin-Like Growth Factor Binding Protein 3 - blood; Insulin-Like Growth Factor Binding Proteins - blood; Insulin-Like Growth Factor I - metabolism; Logistic Models; Male; Medical sciences; Middle Aged; Nephrology. Urinary tract diseases; Prospective Studies; prostate carcinoma; Prostate-Specific Antigen - blood; Prostatic Neoplasms - blood; Prostatic Neoplasms - immunology; Risk; Risk Factors; Time Factors; Tumors of the urinary system; Urinary tract. Prostate gland; Sweden; Europe; Human; Pancreatic hormone; Urinary system disease; Prostate disease; Malignant tumor; Insulin like growth factor 1; Epidemiology; Insulin; Insulin like growth factor binding protein; Protein hormone; Polypeptide; Cohort study; Risk factor; Male genital diseases; Prostate; Growth factor
• ISSN: 0027-8874; 1460-2105; 1460-2105
• DOI: 10.1093/jnci/92.23.1910

Background: Recent studies have suggested that men with elevated plasma levels of insulin-like growth factor-I (IGF-I) may have an increased risk of prostate cancer. Furthermore, IGF-binding proteins (IGFBPs) and insulin can modulate the activity of IGF-I. In this study, we sought to determine the role of IGF-I as well as IGFBPs-1, -2, and -3 and insulin as possible etiologic factors for prostate cancer. Methods: We conducted a nested case–control study within the Northern Sweden Health and Disease Cohort Study. We measured levels of IGF-I, IGFBP-1, IGFBP-2, IGFBP-3, and insulin in plasma samples from 149 men who had a diagnosis of prostate cancer between 1 month and 10 years after blood collection and among 298 control men. All statistical tests are two-sided. Results: Case subjects had statistically significantly higher mean levels of IGF-I than control subjects (229 ng/mL; 95% confidence interval [CI] = 218–240 ng/mL] versus 214 ng/mL [95% CI = 208–221 ng/mL]; P = .02) and IGFBP-3 (2611 ng/mL [95% CI = 2518–2704 ng/mL] versus 2498 ng/mL [95% CI = 2437–2560 ng/mL]; P = .04). Conditional logistic regression analyses showed increases in prostate cancer risk with rising levels of IGF-I (Pfor trend = .02) and IGFBP-3 (Pfor trend = .03). In case subjects younger than 59 years at the time of blood collection, the risk associated with increased IGF-I was higher (Pfor trend = .01), whereas the risk associated with increased IGFBP-3 was lower (Pfor trend = .44) than the corresponding risks in the full cohort. Prostate cancer risk was not associated with levels of IGFBP-1, IGFBP-2, or insulin. Conclusions: Prostate cancer risk is increased in men with elevated plasma IGF-I. This association was particularly strong in younger men in this study, suggesting that circulating IGF-I may be specifically involved in the early pathogenesis of prostate cancer.