Interleukin-6, Interleukin-10 and Heat Shock Protein-90 Expression in Renal Epithelial Neoplasias and Surrounding Normal-Appearing Renal Parenchyma

Abstract

Cytokines, notably the interleukins IL-6 and IL-10, have an important role in the development and progression of renal-cell carcinomas, acting in the host-tumor interaction and in tumor bulk. Heat shock proteins (HSP), in particular HSP-90, may have a regulatory role in cytokine biosynthesis and prognostic implication in some tumors. To define the roles of the cytokines IL-6 and IL-10 and HSP-90 in the progression of renal-cell carcinoma we analyzed immunohistochemical expression of these proteins in human renal-cell carcinomas from 95 total nephrectomies. IL-6, IL-10 and HSP-90 proteins were more strongly expressed in epithelium and stroma of the renal tumoral compartment than in adjacent normal peritumoral tissue. But the difference reached significance only for HSP-90 protein. The percentage of cells expressing IL-6, IL-10 and HSP-90 immunoreactivity was higher in benign epithelial tumors, than in normal peritumoral tissue, but lower than in renal-cell carcinomas. Whereas HSP-90 immunoreactivity seemed higher in more aggressive histological phenotypes (collecting-duct carcinoma) of renal-cell carcinomas, IL-10 protein levels were higher in more advanced TNM stage (pT3) tumors. Our observation suggests that IL-6 and IL-10 and HSP-90 may be useful markers associated with the development and progression of renal-cell carcinomas and have independent functional roles in this malignant condition.