Ontology highlight
ABSTRACT: Background
Increased exposure of colonic and rectal epithelial cells to the promitotic and antiapoptotic effects of insulin and insulin-like growth factors (IGF) is hypothesized to increase colorectal cancer risk.Methods
In a case-control study nested within the Multiethnic Cohort, we attempted to replicate associations for five genetic variants associated with IGF system biomarkers, insulin, or glucose and to examine their association with the risk of colorectal cancer. In a subset of participants, the association between circulating biomarkers and colorectal cancer risk was examined. Unconditional logistic regression was used to calculate ORs and 95% confidence intervals (CI) for genetic variants (1,954 cases/2,587 controls) and serum biomarkers (258 cases/1,701 controls).Results
Associations with circulating biomarkers were replicated in the Multiethnic Cohort for IGF1 rs35767 and for IGFBP3 rs2854744, rs2854746, and rs3110697 (P < 0.05). Homozygous carriers of the glucokinase regulator (GCKR) rs780094 variant T-allele were at a decreased risk of colorectal cancer (OR, 0.77; 95% CI, 0.64-0.92). In risk factor-adjusted models, participants with the highest prediagnostic IGF-II levels were at an increased risk [OR (T1 vs. T3), 1.58; 95% CI, 1.09-2.28; P(trend) = 0.011] and participants with the highest prediagnostic IGF-binding protein (IGFBP)-3 levels were at a decreased risk of colorectal cancer (OR, 0.53; 95% CI, 0.34-0.83; P(trend) = 0.003).Conclusion
These data provide further support for a role of prediagnostic IGF and insulin levels in the etiology of colorectal cancer.Impact
Future studies attempting to replicate the association between the GCKR rs780094 variant and the risk of colorectal cancer are warranted.
SUBMITTER: Ollberding NJ
PROVIDER: S-EPMC4494075 | biostudies-literature | 2012 May
REPOSITORIES: biostudies-literature
Ollberding Nicholas J NJ Cheng Iona I Wilkens Lynne R LR Henderson Brian E BE Pollak Michael N MN Kolonel Laurence N LN Le Marchand Loïc L
Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology 20120221 5
<h4>Background</h4>Increased exposure of colonic and rectal epithelial cells to the promitotic and antiapoptotic effects of insulin and insulin-like growth factors (IGF) is hypothesized to increase colorectal cancer risk.<h4>Methods</h4>In a case-control study nested within the Multiethnic Cohort, we attempted to replicate associations for five genetic variants associated with IGF system biomarkers, insulin, or glucose and to examine their association with the risk of colorectal cancer. In a sub ...[more]