Cadherins and integrins in renal cell carcinoma an immunohistochemical study

Aims and background: The aim of this study was to determine the expression of cadherins and integrins in renal cell carcinoma (RCC) acid their relatio nship with tumor morphology and TNM status. Methods: Cadherin and integrin expression was investigated using an indirec t immunoperoxidase technique, applying antibodies to E-, N-, P- and VE-cadh erin and to alpha (1), alpha (2), alpha (3), alpha (4), alpha (5), alpha (6 ), and alpha (v) integrin subunits, Correlation of semiquantitatively score d adhesion molecule levels with histopathological parameters (cytology, gro wth pattern, nuclear grade) and TNM status was performed for 24 RCCs (17 cl ear cell, 3 granular, 3 spindle cell and 1 chromophobe cell type according to the WHO classification). Results: E-cadherin and N-cadherin were present in most cases (88% and 67%, respectively) and were usually coexpressed, T3 RCCs displayed higher E-cad herin and N-cadherin levels than T1/T2 tumors regardless of tumor grade, su ggesting that impairment of their function might exist without actual loss from tumor cells. P-cadherin was found focally in two RCCs only, while VE-c adherin was present on stromal vessel endothelium in five tumors, showing n o differences with regard to cell type, growth pattern, tumor grade or TNM status. All integrins were present in the studied RCCs (ranging from 12% fo r alpha (5) to 79% for alpha (3)), including those that are normally absent from adult kidney tissue (alpha (4) and alpha (5)), Tumors of higher grade showed increased alpha (v) and decreased ors levels, while RCCs with metas tases less often showed diffuse ors presence and never expressed alpha (5) integrin. Conclusions: Our results suggest that the level of expression of N-cadherin and some integrins (most notably alpha (3), alpha (6), and alpha (5)) is a ssociated with the capacity of RCC for local and distant spread, regardless of tumor grade.