BACKGROUND: The relationships between diet, exercise, and prostate cancer (PCa) remain unclear.
We have previously reported that a "Western" diet promotes PCa tumor growth in vivo. Presently, we report the effects of sustained aerobic exercise on PCa progression in animals fed a high-fat diet versus a standard diet.
METHODS: Athymic mice (n = 43) were inoculated subcutaneously with human PCa (LNCaP) cells, fed ad libitum with either a high-fat or a standard diet, and randomized into forced exercising and non-exercising groups. Body weight, tumor volume, and food consumption were recorded tri-weekly. Terminal serum samples and tumor biopsies were obtained for analysis.
RESULTS: Body weight differences were not observed between the groups over time. The high-fat diet with exercise (HF-Ex) group showed significantly increased tumor growth rate compared to all other groups (P < 0.0007). Tumor growth rate of the standard diet with exercise (Std-Ex) group was reduced significantly compared to the high-fat diet without exercise (HF-No Ex) group (P = 0.0008). Significant differences (P ≤ 0.012) were observed in energy consumption (kcal) between the groups over time. Exercising mice consumed significantly more kcal than non-exercising mice, and the HF-Ex group consumed significantly more than each of the other three groups (P < 0.0007). The expression levels of p27 and p21 were increased in exercising animals, while AR expression was elevated in the HF-Ex group versus the Std-Ex and HF-No Ex groups.
CONCLUSIONS: Sustained aerobic exercise did not counteract the tumor-promotional effect of increased consumption of a high-fat diet, suggesting that diet is more influential in PCa progression than exercise. Combining exercise with a healthy diet reduced the rate of PCa progression in this model. This study may have implications for PCa risk reduction in humans.
Written by:
Vandersluis AD, Venier NA, Colquhoun AJ, Sugar L, Pollak M, Kiss A, Fleshner NE, Klotz LH, Venkateswaran V. Are you the author?
Division of Urology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.
Reference: Prostate. 2013 Apr 30. Epub ahead of print.
doi: 10.1002/pros.22673
PubMed Abstract
PMID: 23630020
UroToday.com Investigative Urology Section
