The interrelationships between Src, Cav-1 and RhoGD12 in transitional cell carcinoma of the bladder

BACKGROUND: The aim of this current study was to assess the expression and activity of Src family kinases, focal adhesion kinase (FAK), caveolin (Cav-1) and RhoGD12 in bladder cancer. METHODS: Fifty-eight patients with a new diagnosis of bladder cancer undergoing transurethral resection were included. Immunohistochemical staining was utilised to assess expression of c-Src, dephosphorylated (SrcY(530)), phosphorylated Src (Y(419)), phosphorylated FAK (FAK Y(861)), Cav-1 and RhoGD12. Expression was assessed using the weighted histoscore method. RESULTS: High expression of dephosphorylated Y(527), phosphorylated Y(416) and phosphorylated FAK Y(861) in the membrane were associated with increased cancer-specific survival (P=0. 01, P=0.001, P=0.008, respectively) and expression of Y(416) in the membrane was an independent factor on multivariate analysis when combined with known clinical parameters (P=0.008, HR 0.288, 95% CI 0.11–0.72). CONCLUSION: These results demonstrate that in contrast to other solid tumours, activation of the Src family members and downstream signalling proteins are associated with a good prognosis in transitional cell carcinoma of the bladder, and activated Src has a positive relationship with RhoGD12.