Development-related expression of KGF and FGF-10 mRNA in the canine prostate gland.

Keratinocyte growth factor (KGF) and fibroblast growth factor 10 (FGF-10) are stromal-derived growth factors that interact with their epithelial FGFR2 receptors to mediate stromal--epithelial cell interaction within the prostate gland. This study was conducted to compare the development-related mRNA expression of KGF, FGF-10 and their receptor FGFR2 in immature and mature canine prostate glands. In addition, their expression levels were correlated with the differentiation of stromal cells using vimentin as a mesenchymal cell marker. Quantitative mRNA expression was assessed by real-time polymerase chain reaction (PCR) and the results were expressed as relative mRNA expression of the target gene, which was normalized to the GAPDH reference gene. mRNA analysis revealed a differential expression of KGF, FGF-10 and FGFR2 receptor by the prostate glands of immature and mature dogs. The results showed a 7.3- and 9-fold decrease in mRNA expression of KGF and FGF-10 by mature and immature prostate glands respectively. However, there was no significant change in FGFR2 receptor mRNA expression by mature or immature prostate glands. This downregulation of KGF and FGF-10 expression was associated with a 15-fold decrease in vimentin expression. These results indicate that KGF and FGF-10 expression varied according to the differentiation status of stromal cells and might reflect differential developmental requirements of immature and mature canine prostate glands.