Expression of the alpha 6 beta 4 integrin provides prognostic information in bladder cancer

Integrins are cell surface receptors for extracellular matrix components th at may participate in metastatic processes. Normal urothelial tissues show a polarized expression of alpha 6 beta 4 integrin on basal cells at their j unction with the lamina propria. Wie have previously shown that bladder can cers frequently overexpress one member of the integrin family, the alpha 6 beta 4 integrin. In this study, we evaluated the level of alpha 6 beta 4 in tegrin expression in bladder cancer specimens from 57 patients and correlat ed the expression level with patient survival. Expression was evaluated by immunoperoxidase staining. Three patterns of alpha 6 beta 4 expression were observed: negative (13 patients); strong overexpression throughout the tum or cells (21 patients); and weak expression that most closely resembled exp ression in normal urothelium (23 patients). Individuals with weak staining tumors had a statistically significantly better survival (p=0.041) than pat ients whose tumors exhibited either no expression or strong overexpression. These data indicate that evaluation of the expression of alpha 6 beta 4 in tegrin may provide valuable prognostic information on clinical outcome in p atients with bladder cancer.