A low-fat diet and/or strenuous exercise alters the IGF axis in vivo and reduces prostate tumor cell growth in vitro.
BACKGROUND
Prostate cancer is the most common solid-tumor cancer in US males but is rare in Asian males. When Asian men adopt the US lifestyle, clinical prostate cancer increases greatly. Epidemiological data from men in the US indicate that regular activity may reduce the risk for prostate cancer.


METHODS
Serum was obtained from three groups of similar-aged men, Control, Diet and Exercise, and Exercise alone were used to stimulate LNCaP cells in culture. Growth and apoptosis of tumor cells were measured. Serum samples were also used to measure insulin, IGF-1, IGFBP-1.


RESULTS
The Diet and Exercise and the Exercise alone groups had lower serum insulin and IGF-1 but higher IGFBP-1 compared to Controls. LNCaP cell growth was reduced in both groups compared to Control and there was a major increase in apoptosis of tumor cells.


CONCLUSIONS
A low-fat diet and/or intensive exercise results in change in serum hormones and growth factors in vivo that can reduce growth and induce apoptosis of LNCaP prostate tumor cells in vitro.
Barnard
R James
RJ
Department of Physiological Science, University of California-Los Angeles, 621 Charles E. Young Drive S., Los Angeles, CA 90095-1606, USA. jbarnard@physci.ucla.edu
Ngo
Tung H
TH
Leung
Pak-Shan
PS
Aronson
William J
WJ
Golding
Lawrence A
LA
D017209:Apoptosis; D002455:Cell Division; D018752:Diet, Fat-Restricted; D015444:Exercise; D006801:Humans; D007004:Hypoglycemic Agents / Q000097:blood*; D007328:Insulin / Q000097:blood*; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008019:Life Style; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000178:diet therapy* / Q000503:physiopathology*; D012307:Risk Factors; D014407:Tumor Cells, Cultured
D007004:Hypoglycemic Agents; D007328:Insulin; D018970:Insulin-Like Growth Factor Binding Protein 1; D007334:Insulin-Like Growth Factor I