Effect of castration on Hox gene expression in the separate adult prostate lobes. Prostatic Hox gene expression was measured 48 h after castration and in sham-intact rats as controls. Bars represent mean ± sem for six samples per treatment. A, Although expression of Hoxa9 and Hoxa13 was increased by androgen withdrawal in the adult VP, all other Hox genes were unaffected. B and C, Hox gene expression in the LP and DP, respectively, was largely unaffected by androgen withdrawal with the exception of Hoxb13, which was significantly reduced. *, P < 0.05; **, P < 0.01 castration vs. sham.