Cadherins and Integrins in Renal Cell Carcinoma an Immunohistochemical Study

Abstract

Aims and Background

The aim of this study was to determine the expression of cadherins and integrins in renal cell carcinoma (RCC) and their relationship with tumor morphology and TNM status.

Methods

Cadherin and integrin expression was investigated using an indirect immunoperoxidase technique, applying antibodies to E-, N-, P- and VE-cadherin and to α₁, α₂, α₃, α₄, α₅, α₆ and α_v integrin subunits. Correlation of semiquantitatively scored adhesion molecule levels with histopathological parameters (cytology, growth pattern, nuclear grade) and TNM status was performed for 24 RCCs (17 clear 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 coex-pressed. T3 RCCs displayed higher E-cadherin and N-cadherin levels than T1/T2 tumors regardless of tumor grade, suggesting that impairment of their function might exist without actual loss from tumor cells. P-cadherin was found focally in two RCCs only, while VE-cadherin was present on stromal vessel endothelium in five tumors, showing no differences with regard to cell type, growth pattern, tumor grade or TNM status. All integrins were present in the studied RCCs (ranging from 12% for α₅ to 79% for α₃), including those that are normally absent from adult kidney tissue (α₄ and α₅). Tumors of higher grade showed increased α_v and decreased α₆ levels, while RCCs with metastases less often showed diffuse α₃ presence and never expressed α₅ integrin.

Conclusions

Our results suggest that the level of expression of N-cadherin and some integrins (most notably α₃, α₆, and α₅) is associated with the capacity of RCC for local and distant spread, regardless of tumor grade.