Insulin-like growth factor II and colorectal cancer risk in women.
Recently, a number of prospective studies showed evidence that the growth hormone/insulin-like growth factor I (IGF-I) axis may be important in the development of colorectal cancer. However, only a few studies have reported on the possible relationship of colorectal cancer risk with circulating levels of IGF-II, which are not growth hormone dependent and which do not vary with alterations in energy balance. In a case-control study of 102 cases and 200 matched controls nested within a cohort of 14,275 women in New York, we examined the relationship between colorectal cancer risk and prediagnostic serum levels of IGF-II. Conditional logistic regression analysis showed an odds ratio (OR) for colorectal cancer of 2.02 (95% confidence interval (CI): 0.83-4.93), comparing the upper to lower quintile of IGF-II. This association was slightly attenuated after excluding IGF-II measurements in serum samples taken within 1 year before case diagnosis (OR of 1.81; 95% CI: 0.71-4.64) and moderately attenuated after excluding IGF-II measurements in serum samples taken within 2 years before case diagnosis (OR of 1.47; 95% CI: 0.56-3.91). Adjustment for IGF-1, IGF binding protein (BP)-1, IGFBP-3, smoking, or body mass index did not substantially alter the association, whereas adjustment for IGFBP-2 moderately attenuated the relationship. Our results confirm those of three recent case-control studies, and collectively these results suggest a possible increase in colorectal cancer risk among subjects with comparatively elevated serum IGF-II. Mechanisms that might cause the increase in IGF-II levels are unknown but may include loss of parental imprinting of the IGF-II gene.
Hunt
Kelly J
KJ
International Agency for Research on Cancer, 69372 Lyon Cedex 08, France.
Toniolo
Paolo
P
Akhmedkhanov
Arslan
A
Lukanova
Annekatrin
A
Dechaud
Henri
H
Rinaldi
Sabina
S
Zeleniuch-Jacquotte
Anne
A
Shore
Roy E
RE
Riboli
Elio
E
Kaaks
Rudolf
R
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000097:blood / Q000209:etiology*; D015179:Colorectal Neoplasms / Q000097:blood / Q000209:etiology*; D005260:Female; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000032:analysis / Q000378:metabolism*; D008875:Middle Aged; D016017:Odds Ratio; D011446:Prospective Studies; D012307:Risk Factors
D007335:Insulin-Like Growth Factor II