title: Insulin-like growth factor (IGF)-I, IGF-binding protein-3 and colorectal adenomas in Japanese men.
abstract: Several epidemiological studies have found that high levels of plasma insulin-like growth factor (IGF)-I and low levels of IGF-binding protein (IGFBP)-3 are related to an increased risk of colorectal cancer or late-stage adenomas. We examined the relation of body mass index, fasting and 2-h postload plasma glucose levels and plasma concentrations of IGF-I and IGFBP-3 to colorectal adenomas in middle-aged Japanese men. The study subjects comprised 157 cases of histologically diagnosed colorectal adenomas and 311 controls with normal colonoscopy or non-polyp benign lesions in a consecutive series of 803 men receiving a preretirement health examination at two hospitals of the Self Defense Forces (SDF). After adjustment for rank in the SDF, hospital, smoking and IGFBP-3, a statistically nonsignificant modest increase in the prevalence odds of colorectal adenomas was observed for the highest versus the lowest quartile level of IGF-I. The increase was slightly greater with further adjustment for 2-h glucose concentrations (adjusted odds ratio 1.8, 95% confidence interval 1.0-4.5, trend P=0.06). Men with high levels of IGFBP-3 showed only a minimal decrease in risk after adjustment for IGF-I. The association with IGF-I was less evident for advanced adenomas (>5 mm in size or tubulovillous/villous). Fasting and 2-h glucose and body mass index were more strongly positively associated with colorectal adenomas than IGF-I, especially with advanced adenomas, independently of IGF-I and IGFBP-3. The findings suggest that plasma IGF-I and IGFBP-3 may be involved in colorectal tumorigenesis regardless of the stage in growth of adenoma, but not as a mediator for the effects of being overweight or of hyperglycemia.
authors.affiliation: Department of Preventive Medicine, Faculty of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Teramukai
authors.forename: Thomas
authors.initials: T
authors.lastname: Rohan
authors.forename: Kyong-Yeon
authors.initials: KY
authors.lastname: Lee
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Eguchi
authors.forename: Takashi
authors.initials: T
authors.lastname: Oda
authors.forename: Suminori
authors.initials: S
authors.lastname: Kono
mesh_terms: D000236:Adenoma / Q000097:blood* / Q000209:etiology; D015179:Colorectal Neoplasms / Q000097:blood* / Q000209:etiology; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D012306:Risk
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I