Variation in Plasma Insulin-like Growth Factor-1 and Insulin-like Growth Factor Binding Protein-3: Personal and Lifestyle Factors (United States)

Abstract

Insulin-like growth factors (IGFs) play an important role in cell proliferation and apoptosis, and recent epidemiologic studies have suggested that circulating IGF-1 and IGF binding protein-3 (IGFBP-3) may be related to colorectal, breast, and prostate cancer risk. The purpose of this analysis was to investigate the role of various personal and lifestyle factors in the inter-individual variation of circulating IGF-1 and IGFPB-3. We measured plasma levels of IGF-1 and IGFBP-3 in a sequential sample of 333 population-based control subjects enrolled in the Seattle Colorectal Cancer Family Registry from August 1999 through December 2001, who had provided a blood sample. Total IGF-1 and IGFBP-3 were measured from plasma samples using ELISA assays. Interviewer-administered questionnaires collected data on various personal and lifestyle factors. Multivariate-adjusted linear regression was used to assess the associations between specific personal and lifestyle factors with IGF-1 and IGFBP-3 levels. Age, body mass index, and postmenopausal hormone use were statistically significantly inversely related to IGF-1 concentrations, and milk consumption was significantly positively related to IGF-1 levels. Only age was significantly related to circulating IGFBP-3. Although the sources of inter-individual variation of IGF-1 and IGFB-3 are not yet fully understood, this analysis provides some insights into factors that may contribute.

Do Factors Related to Endogenous and Exogenous Estrogens Modify the Relationship between Obesity and Risk of Colorectal Adenomas in Women?

“…In addition, estrogen may alter colorectal cancer risk directly via estrogen receptors in the colonic mucosa (55). Furthermore, changes in the metabolic profile, specifically in the insulin/IGF axis resulting from excess adipose tissue, may also play a role in increasing colorectal cancer risk (36); estrogen is believed to exert a protective effect through the insulin/IGF axis by reducing serum IGF levels (56). In addition, it should be noted that, among postmenopausal women, adipose tissue is the principal source of endogenous estrogen (37).…”

Ethnic Disparity in the Relationship between Obesity and Plasma Insulin-Like Growth Factors: The Multiethnic Cohort

“…Studies among healthy adults have reported a null association (2-4), a positive association (5), an inverse association (6)(7)(8)(9), and a nonlinear association (10,11) between BMI and IGF-I levels. The nonlinear associations were similar to what we observed in Japanese Americans.…”

“…Previous studies, however, have been inconsistent with respect to the relationships between adiposity and circulating levels of IGF proteins (2)(3)(4)(5)(6)(7)(8)(9)(10)(11). Studies among healthy adults have reported a null association (2-4), a positive association (5), an inverse association (6)(7)(8)(9), and a nonlinear association (10,11) between body mass index (BMI) and IGF-I levels. We are unaware of any study that has looked at possible ethnic differences in the relationship between obesity and circulating IGF-I, and this may be important in addressing the metabolic basis for ethnic differences in cancer risk.…”

Effects of oral and transdermal estrogen on IGF1, IGFBP3, IGFBP1, serum lipids, and glucose in patients with hypopituitarism during GH treatment: a randomized study

“…Small intervention studies (2,3,4,5,6,7,8,9,10) and large cross-sectional studies (11,12,13,14,15) have demonstrated that oral estrogens reduce serum concentrations of total IGF1. These findings have been observed both in menopausal women and in those with hypopituitarism.…”

“…Studies of oral estrogens have provided inconsistent results in relation to IGFBP3 concentrations, with reports of reduced serum levels (5,7,13,22,23) or an absence of effects (2,4,6,12,14,15).…”