title: Increase in circulating levels of IGF-1 and IGF-1/IGFBP-3 molar ratio over a decade is associated with colorectal adenomatous polyps.
abstract: High levels of circulating insulin-like growth factor-1 (IGF-1) have been associated with increased risk of several cancers. Regarding colorectal cancer, these associations are generally weak. We hypothesized that an increase in IGF-1 over time would be a stronger risk factor for cancer-related outcomes than the actual levels. In this analysis we utilized existing data from the Insulin Resistance and Atherosclerosis Study (IRAS). Circulating IGF-1 levels and molar ratios of IGF-1 to IGF binding protein 3 (IGFBP-3) were measured at three time points, within a 10-year follow-up period. We examined the associations of increase of the two variables with the presence of colorectal adenoma at the end of follow-up among participants with normal glucose tolerance at baseline. This included 143 individuals, from which 24 were diagnosed with adenomatous polyps. Although the mean levels of IGF-1 and IGF-1/IGFBP-3 decline with age, ~ 30% of the participants showed an increase of at least fifteen percent ("ever increase") in one or both of these variables, compared to baseline. We found a positive association between "ever increase" in IGF-1 or IGF-1/IGFBP-3 and the presence of colorectal adenoma: ORs were 3.81 (95% CI: 1.30-10.8) and 2.83 (95% CI: 1.00-8.22), respectively. No association was found when analyzing the actual levels of both variables at any time point. Our data suggest that an increase in circulating IGF-1 or IGF-1/IGFBP-3 may represent a disturbed GH/IGF1 homeostasis, which could favor the development of precancerous lesions such as colorectal adenoma.
authors: Duke Cancer Institute, Duke University, Durham, NC 27710, USA.
authors: Adelheid
authors: A
authors: Soubry
authors: Dora
authors: D
authors: Il'yasova
authors: Rebecca
authors: R
authors: Sedjo
authors: Frances
authors: F
authors: Wang
authors: Tim
authors: T
authors: Byers
authors: Clifford
authors: C
authors: Rosen
authors: Anatoli
authors: A
authors: Yashin
authors: Svetlana
authors: S
authors: Ukraintseva
authors: Steven
authors: S
authors: Haffner
authors: Ralph
authors: R
authors: D'Agostino
mesh_terms: D018256:Adenomatous Polyps / Q000097:blood* / Q000473:pathology; D000328:Adult; D000368:Aged; D003111:Colonic Polyps / Q000097:blood* / Q000473:pathology; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000097:blood* / Q000473:pathology; D005260:Female; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000096:biosynthesis / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I