Growth factor expression profile in prostates of WT and FSP-ARKO mice. The expressions of (A) growth factors IGF-1, FGF-7, FGF-10, HGF, and (B) epithelial specific genes in the prostates of WT and FSP-ARKO mice at 6, 12, and 24 weeks were detected by Q-PCR. All the gene expression levels of FSP-ARKO mice were normalized by WT littermates (**P < 0.01 vs. WT littermates, *P < 0.05 vs. WT littermates; n = 4).