Accumulation of FGF9 in Prostate Cancer Correlates with Epithelial-to-Mesenchymal Transition and Induction of VEGF-A Expression

Abstract The aim of the present study was to investigate the molecular mechanism of fibroblast growth factor (FGF)-9 in prostate cancer cells. Expression of vascular endothelial growth factor (VEGF)s and cadherins in LNCaP cells by incubation with FGF9 was assessed by western blot analysis. Tissues obtained during a radical prostatectomy in 88 patients were immunohistochemically-stained using anti-FGF9, anti-cadherin, and anti-VEGF antibodies. Expression of N-cadherin and VEGF-A were induced in LNCaP cells incubated in FGF9-containing medium. The biochemical relapse-free survival rate in cases with FGF9, N-cadherin and VEGF-A-positive cells was significantly lower than the rate in cases where positive cells were not detectable. The prevalence of both VEGF-A- and N-cadherin-positive cells in the sample with FGF9-positive cells were significantly higher in comparison to FGF9-negative cases. FGF9 can be associated with epithelial-to-mesenchymal transition and invasion by inducing VEGF-A expression in prostate cancer cells.