['This study investigated the effects of finasteride, a 5alpha-reductase inhibitor, clinically used for the treatment of benign prostatic hyperplasia (BPH) on prostate tumor vascularity, apoptosis, and cell adhesion in situ and in vitro.', 'Prostate specimens from BPH patients treated with finasteride for 1-12 months (n = 13), or without finasteride treatment (n = 14), were evaluated for apoptosis (TUNEL assay), microvessel density (Factor VIII), and prostate specific antigen (PSA) immunoreactivity. In vitro, the effect of finasteride was investigated in benign prostate cells, BPH-1, and its tumorigenic derivatives, CAFTD-01 and CAFTD-03, using Hoechst staining and cell adhesion assays.', 'A significant increase in the apoptotic index, and reduced microvessel density and PSA expression were detected in prostates from finasteride-treated patients, compared to controls (P < 0.01). In vitro finasteride led to a significant decrease in prostate epithelial cell adhesion (P < 0.05).'] Does finasteride target prostate vascularity by inducing apoptosis and inhibiting cell adhesion of benign and malignant prostate cells?