Insulin-like growth factors and risk of kidney cancer in men.
BACKGROUND
Insulin-like growth factor-I (IGF-I) has been shown to increase kidney growth, glomerular filtration rate, and renal function.


METHODS
In the prospective Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) study of 29 133 Finnish male smokers aged 50-69 years, serum concentrations of IGF were measured in samples collected in 1985-1988. A total of 100 men with kidney cancer diagnosed > or =5 years after blood collection through 1997 were compared with a subcohort of 400 men; logistic regression models were used to estimate the risk of developing kidney cancer.


RESULTS
Men with IGF-I levels >113 ng ml(-1) were 59% less likely to develop kidney cancer than men with levels < or =113 ng ml(-1) (odds ratio=0.41; 95% confidence interval=0.23-0.75). The IGF binding protein-3 (IGFBP-3) levels did not alter the association. No association was observed between IGFBP-3, or molar ratio of IGF-I/IGFBP-3, and kidney cancer.


CONCLUSIONS
Low serum IGF-I levels in this cohort of older middle-aged male smokers are associated with increased kidney cancer risk, independent of IGFBP-3.
Major
J M
JM
Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, Maryland 20852, USA. jacqueline.major@nih.gov
Pollak
M N
MN
Snyder
K
K
Virtamo
J
J
Albanes
D
D
D000368:Aged; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D007680:Kidney Neoplasms / Q000097:blood / Q000209:etiology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects
D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I