Prostate Cancer Cell Viability and Migration in Serum and Prostate Conditioned Media from Moderate‐Intensity Exercise Trained Rats

Abstract

Physical activity is associated with diminished risk of several cancers and preclinical studies suggest exercise training may alter tumor cell growth in certain tissues (e.g., adipose). We hypothesized that serum and prostate conditioned media (PCM) from moderate‐intensity exercise trained rats will decrease prostate cancer cell growth, while prostate 5α‐reductase 2 expression will decrease. We evaluated the effects of serum and PCM from moderate‐intensity exercise trained rats on prostate cancer cell viability and migration. In addition, we determined whether moderate‐intensity exercise training would modulate 5α‐reductase 2 protein expression, an essential component of androgen metabolism in prostate cancer. Male Copenhagen rats (~2–3 mo old) were randomly assigned to an exercise‐trained group (n = 10) and a sedentary control group (n = 10). The exercise‐trained rats ran on a motorized treadmill for 5 days/week at 15 m/min, 15° incline for 60 min/day for a 10‐ to 11‐week training period. Serum was collected from both rat groups, and used to supplement media at 5% concentration with and without 5% fetal bovine serum (FBS). Rat prostates were harvested, cut into two approximately equal sections with one section incubated with media for 24 hours to prepare PCM, and immunohistochemistry performed on the other section to quantify 5α‐reductase 2 expression. Dunning R‐3327 AT‐1 prostate cancer cells were grown in PCM, or media supplemented with either 5% serum from the exercise‐trained or sedentary groups with and without 5% FBS for 24–96 hours. Tumor cell viability and migration were determined using MTT and transwell migration assays, respectively. Serum or PCM from exercise‐trained rats did not significantly decrease cell viability compared to serum (e.g. 0.41 ± 0.04 vs. 0.50 ± 0.05 viable cell number, p = 0.14) or PCM (e.g. 0.40 ± 0.07 vs. 0.50 ± 0.08 viable cell number, p = 0.50; all at 48 hour incubation) from sedentary rats, respectively. However, the addition of FBS to serum from exercise‐trained rats significantly decreased cell viability compared to FBS and serum from sedentary rats (e.g. 0.49 ± 0.05 vs. 0.69 ± 0.06 viable cell number, p = 0.02; 48 hour incubation). Serum alone, serum and FBS, or PCM from exercise‐trained rats did not significantly impact cell migration compared to sedentary control (54.7 ± 3.3 vs. 64.2 ± 9.2 cells/field, p = 0.27; 29.3 ± 2.6 vs. 29.3 ± 2.5 cells/field, p > 0.99; 55.9 ± 10.5 vs. 52.8 ± 8.1 cells/field, p = 0.82), respectively. 5α‐reductase 2 in the prostate was not significantly changed with exercise compared to sedentary group (0.87 ± 0.21 vs. 0.78 ± 0.18 positive cells/tissue area (μm2), p = 0.76). In conclusion, prior exercise status did not modify several key characteristics of prostate tumor cell growth and viability from conditioned media from host‐tissue (prostate) or serum in vitro. Whether exercise training alters similar prostate tumor cell growth characteristics in vivo is unknown.Support or Funding InformationAmerican Cancer Society RSG 14‐150‐1‐CCE (BJB)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.