A prospective study of C-peptide, insulin-like growth factor-I, insulin-like growth factor binding protein-1, and the risk of colorectal cancer in women.
Cancer Epidemiol Biomarkers Prev
; 14(4): 850-5, 2005 Apr.
Article
em En
| MEDLINE
| ID: mdl-15824155
ABSTRACT
Hyperinsulinemia, hyperglycemia, and elevated insulin-like growth factor (IGF)-1 levels have been implicated in the etiology of colorectal cancer. However, the joint effects of insulin and IGF-I have not been considered, and whether hyperinsulinemia or hyperglycemia is more etiologically relevant is unclear. IGF binding protein-1 (IGFBP-1) has been hypothesized to mediate the effects of insulin, but epidemiologic data on IGFBP-1 are sparse. We conducted a nested case-control study among the 32,826 women of the Nurses' Health Study who provided a blood sample in 1989 to 1990. After excluding diabetics, we confirmed 182 incident colorectal cancer cases over 10 years of follow-up and 350 controls. Cases were matched to two controls on year of birth, date of blood draw, and fasting status. C-peptide levels were weakly associated with risk of colon cancer [top quartile (Q4) versus bottom quartile (Q1) multivariable relative risk (MVRR), 1.76; 95% confidence interval (95% CI), 0.85-3.63]. Fasting IGFBP-1 was inversely associated with risk of colon cancer (MVRR, 0.28; 95% CI, 0.11-0.75). We observed no clear association between glycosylated hemoglobin and risk for colorectal cancer. The IGF-I to IGFBP-3 molar ratio was associated with colon cancer risk (MVRR, 2.82; 95% CI, 1.35-5.88), and women with low levels of both IGF-I/IGFBP-3 and C-peptide (or high IGFBP-1) were at low risk, and elevation of either was sufficient to increase risk. Although altering IGF-I levels may not be practical, the growing burden of obesity and consequently hyperinsulinemia, which seems increasingly important for colon cancer, may be a target for effective prevention.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeo C
/
Fator de Crescimento Insulin-Like I
/
Neoplasias Colorretais
/
Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina
/
Hiperglicemia
/
Hiperinsulinismo
Tipo de estudo:
Etiology_studies
/
Observational_studies
/
Risk_factors_studies
Limite:
Adult
/
Female
/
Humans
/
Middle aged
Idioma:
En
Revista:
Cancer Epidemiol Biomarkers Prev
Assunto da revista:
BIOQUIMICA
/
EPIDEMIOLOGIA
/
NEOPLASIAS
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Estados Unidos