Risk of ovarian cancer in relation to prediagnostic levels of C-peptide, insulin-like growth factor binding proteins-1 and -2 (USA, Sweden, Italy).
OBJECTIVE
To investigate the association of prediagnostic circulating levels of C-peptide, as a marker of pancreatic insulin secretion, and IGF binding proteins -1 and -2, as indicators of the biologically active IGF-I concentration, with risk of developing ovarian cancer.


METHODS
The study was nested within three prospective cohorts in New York (USA), Umeå (Sweden) and Milan (Italy). Case subjects were 132 women with primary invasive epithelial ovarian cancer diagnosed at least one year after blood donation. For each case, two control subjects were selected, matching the case subject on cohort, menopausal status, age and date of recruitment (n = 263). Only women who did not use exogenous hormones at blood donation were included in the study.


RESULTS
Odds ratios and their 95% confidence intervals for risk of developing ovarian cancer over quartiles of peptides concentrations after adjustment for BMI and fasting were: 1.00, 0.66 (0.35-1.23), 0.96 (0.51-1.82) and 0.89 (0.44-1.81) for C-peptide; 1.00, 1.10 (0.58-2.09), 1.07 (0.55-2.04) and 0.79 (0.38-1.62) for IGFBP-1; and 1.00, 1.01 (0.54-1.89), 0.98 (0.51-1.88) and 0.87 (0.45-1.68) for IGFBP-2. In women who had ovarian cancer diagnosis before age 55 the ORs for the top tertiles of IGFBP-1 and IGFBP-2 were 0.51 (0.18-1.49) and 0.53 (0.18-1.54), respectively.


CONCLUSIONS
This study does not support an independent direct etiological role of C-peptide in ovarian cancer pathogenesis, but suggests a possible protective effect of circulating IGFBP-1 and -2 in women who develop ovarian cancer before age 55.
Lukanova
Annekatrin
A
International Agency for Research on Cancer, Lyon, France.
Lundin
Eva
E
Micheli
Andrea
A
Akhmedkhanov
Arslan
A
Rinaldi
Sabina
S
Muti
Paola
P
Lenner
Per
P
Biessy
Carine
C
Krogh
Vittorio
V
Riboli
Elio
E
Hallmans
Göran
G
Berrino
Franco
F
Zeleniuch-Jacquotte
Anne
A
Toniolo
Paolo
P
Kaaks
Rudolf
R
D000328:Adult; D000368:Aged; D002096:C-Peptide / Q000097:blood*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000097:blood*; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000097:blood*; D007558:Italy; D008875:Middle Aged; D016017:Odds Ratio; D010051:Ovarian Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D014481:United States / Q000453:epidemiology
D002096:C-Peptide; D018970:Insulin-Like Growth Factor Binding Protein 1; D018971:Insulin-Like Growth Factor Binding Protein 2