Decreased RECK and Increased EMMPRIN expression in urothelial carcinoma of the bladder are associated with tumor aggressiveness

Abstract

Objective: Urothelial bladder carcinomas show a divergent biological behavior, which significantly complicates risk stratification and clinical management. The MMP repressor RECK and the MMP activator EMMPRIN regulate the invasive potential by metalloproteinase-induced stromal degradation. Data on RECK in urothelial bladder cancer are lacking and information on EMMPRIN is sparse. This study aims to investigate the expression of RECK and EMMPRIN in urothelial carcinoma of the bladder and to correlate these findings with clinicopathological parameters.

Methods: Our study included 127 specimens of urothelial carcinomas derived from 103 patients who underwent either TUR-B or cystectomy. Immunohistochemical expression analysis was performed for RECK, EMMPRIN, MMP-2, MMP-9 and MMP-14. Expression levels were graded for staining intensity and correlated with pT stage and WHO tumor grade.

Results: Invasive (≥pT1) as well as WHO high-grade urothelial carcinomas showed a statistically significant and stepwise downregulation of RECK (p < 0.001) and concomitant upregulation of EMMPRIN (p < 0.001) compared to non-invasive and WHO low-grade tumors. No correlation was observed for the MMPs investigated.

Conclusion: Decreased RECK and increased EMMPRIN expression are associated with increasing stage and grade. Both proteins may serve as molecular marker for the distinction between potentially invasive (≥pT1) and non-invasive tumors (≤pTa).