AR immunostaining in TRAMP mice. Mice were euthanized at 5 months, and prostates were analyzed for AR immunostaining. Normal prostates from non-TRAMP mice were stained as control. A, PIN lesion. B, WDC lesion. C, PDC lesion. D, Plot of IHC scores. n = 49, from studies 1 and 5–7 (see Supplemental Table 2). There is a very significant reduction of AR expression in PDC tumors. Scale bar, 20 μm. Inset in A shows negative control without antibody. *, P < 0.05.