Epithelial cell expression of SV40-Tag in TRAMP prostates following castration (Cx). Dorsal prostate Day 1 postcastration (A) and Day 4 postcastration (B); Lateral prostate Day 1 postcastration (C) and Day 4 postcastration (D); Ventral prostate Day 1 postcastration (E) and Day 4 postcastration (F) immunostained for SV40-Tag. (G) The percent of epithelial cells expressing SV40-Tag in each lobe of the prostate ▪ dorsal, □ lateral, and ventral. ***P < .001: Days 4, 7, and 14 postcastration compared to sham-castrated animals in all lobes and Day 2 postcastration in the dorsal lobe only. *P < .05: Day 2 postcastration compared to sham castration in the lateral lobe. Black arrows, SV40-Tag - expressing cells Day 4 postcastration. Scale bar, 20 µm.