No effect of red clover-derived isoflavone intervention on the insulin-like growth factor system in women at increased risk of colorectal cancer.
Publication year
2008Source
Cancer Epidemiology, Biomarkers & Prevention, 17, 10, (2008), pp. 2585-93ISSN
Publication type
Article / Letter to editor
Display more detailsDisplay less details
Organization
Health Evidence
Former Organization
Epidemiology, Biostatistics & HTA
Journal title
Cancer Epidemiology, Biomarkers & Prevention
Volume
vol. 17
Issue
iss. 10
Page start
p. 2585
Page end
p. 93
Subject
NCEBP 1: Molecular epidemiology; ONCOL 1: Hereditary cancer and cancer-related syndromes; ONCOL 3: Translational research; ONCOL 5: Aetiology, screening and detection; UMCN 1.2: Molecular diagnosis, prognosis and monitoringAbstract
BACKGROUND: Increased insulin-like growth factor (IGF)-I and IGF-II concentrations are related to increased colorectal cancer risk. Isoflavones have been associated with reduced colorectal cancer risk, and may affect the IGF system because of their weak estrogenic activity. The aim of the study was to investigate the effect of isolated isoflavones on serum concentrations of IGF system components. MATERIALS AND METHODS: We conducted a randomized, placebo-controlled, double-blinded, crossover trial in four hospitals in the Netherlands to investigate the effect of an 8-week supplementation with red clover-derived isoflavones (84 mg/d) on serum IGF-I concentrations. In addition, serum concentrations of IGF-II and IGF binding proteins (IGFBP)-1, IGFBP-2, and IGFBP-3 were assessed. Normal colorectal tissue biopsies were obtained after the first intervention period and mRNA expression of IGF-I, IGF-II, IGFBP-3, and IGF-IR was evaluated. Our study population consisted of 34 postmenopausal women with a family history of colorectal cancer or a personal history of colorectal adenomas. RESULTS: Isoflavone supplementation did not significantly affect serum concentrations of total IGF-I (mean relative within-person difference; IGF-I, -2.0%; 95% confidence interval, -8.0% to 3.9%). IGF-II and IGFBPs were also not significantly altered after isoflavone supplementation. Colorectal tissue mRNA expression of IGF system components did not significantly differ between individuals on isoflavone supplementation and those who received placebo. CONCLUSIONS: The results of our trial, supported by a qualitative review of soy trials published to date, suggest that isoflavones do not significantly affect circulating levels of IGF system components. Increased levels of IGF-I, as observed in most of these trials, are likely due to simultaneous protein supplementation.
This item appears in the following Collection(s)
- Academic publications [238441]
- Faculty of Medical Sciences [90373]
Upload full text
Use your RU credentials (u/z-number and password) to log in with SURFconext to upload a file for processing by the repository team.