Background: Renal cancer is one of the ten most common malignant tumours in humans and its histological classification, best clinical management and treatment strategies are continuously debated. Roughly 10% of renal carcinomas are papillary renal cell carcinomas (RCCs), a histologically well characterized tumour subtype that is linked to alterations on chromosomes 7 and 17. Peptidases are proteolytic enzymes known to be involved in oncological processes, although their precise role in renal cancer is poorly understood.
Materials and methods: Eighteen papillary RCCs were selected for the study. Tumour and normal tissue samples were frozen for enzymatic analysis. The catalytic activity for a pool of peptidases (EC numbers: 3.4.11.14; 3.4.11.2; 3.4.11.6; 3.4.11.21; 3.4.11.7; 3.4.14.5; 3.4.24.11; 3.4.21.26; 3.4.19.3) was measured fluorometrically.
Results: Statistically significant decreases were observed in the following cell surface activities: EC.3.4.11.2 (six-fold decrease in tumour vs. non-tumour); 3.4.11.6 (five-fold decrease); 3.4.11.7 (eight-fold decrease); 3.4.24.11 (four-fold decrease). No significant alterations were observed in the soluble activities.
Conclusion: These data confirm the involvement of cell-surface peptidases in the mechanisms underlying RCC aetiogenesis and suggest that the peptidase activity profile in the RCC may be a diagnostic/prognostic marker.