Growth factors in expressed prostatic fluid from men with prostate cancer,BPH, and clinically normal prostates

BACKGROUND. Although growth factors such as epidermal growth factor (EGF), transforming growth factor (TGF)-alpha, and TGF-beta are important regulato rs of prostate cell growth in vitro and in animal models, evidence to suppo rt their role in human prostate cancer development remains sparse. We previ ously showed that men without prostate cancer have concentrations of EGF an d TGF-alpha in expressed prostatic fluid (EPF) that are individually distin ct and stable over time. This study addressed whether growth factor levels in EPF are associated with the presence or progression of prostate cancer. METHODS. We measured levels of immunoreactive EGF, TGF-alpha, and TGF-beta 1 in stored EPF samples from three age-matched groups: 19 men with untreate d, histologically diagnosed prostate cancer (CaP), 38 with benign prostate hyperplasia (BPH), and 19 with normal prostate glands (NPD). RESULTS. Median TGF-alpha was lower in the BPH group(0.45 ng/ml) than in ei ther CaP (0.63 ng/ml) or NPD (0.58 ng/ml) groups (P = 0.03 and 0.12, respec tively). For EGF, the median was lowest in the CaP group and highest in the NPD group (92.5 ng/ml vs. 175.5 ng/ml, P = 0.006). For TGF-beta 1, the med ian level in CaP was 2.7 times higher than the median level among all contr ols (6.65 ng/ml vs. 2.46 ng/ml, P = 0.002). Growth factor levels were not a ssociated with tumor stage or Gleason score. However, the single ease with distant metastases had TGF-beta 1 levels 23-fold higher than the CaP median . CONCLUSIONS. The results suggest that at the time of CaP diagnosis, EGF lev els in EPF are significantly lower, and TGF-beta 1 levels significantly hig her, than normal. Marked overexpression of TGF-beta 1 in advanced CaP might be reflected in extremely high EPF levels. (C) 1999 Wiley-Liss, Inc.