Stromelysin-1 and stromelysin-2 (matrix metalloproteinase 3; MMP-3 and matrix metalloproteinase 10; MMP-10, respectively) are enzymes that activate other metalloproteinases. Apart from collagen, they also degrade elastin, fibronectin, gelatin and laminin. In carcinogenic processes, they are involved in angiogenesis and metastasis. Therefore, the aim of this study was to evaluate the DNA content, expression and activity of both stromelysines in cancers of human kidney. Renal carcinoma tissue samples were analyzed. Low- and high-grade cancer tissues were collected. Control material was collected from part of the kidney opposite to the tumor. DNA content, stromelysines content and stromelysin-1 and stromelysin-2 activity were measured using ELISA and Western blot methods. A higher content of deoxyribonucleic acid in low- and high-grade cancer tissues in comparison to the respective control tissue was observed. Both stromelysines were presented in control and cancer tissues in high-molecular-weight complexes. The content of MMP-10 was significantly higher in comparison to MMP-3 in all investigated tissues. Moreover, the content of stromelysin-2 was significantly higher in high-grade (G3) tissues compared to grade 2 (G2) kidney cancer. A significant decrease in the actual and specific activities of both stromelysines was observed with the increase in renal cancer grade. The presented results may indicate that the degradation of extracellular matrix increases with a higher grade of cancer. Moreover, the elevated content and decreased specific activity of stromelysin-2 in cancer tissue indicate that MMP-10 is mainly present in an inactive form in renal carcinoma. Detailed knowledge of the mechanism and participation of stromelysines in extracellular matrix degradation may be important in understanding the pathomechanism of renal cancer development. Therefore, the potential application of stromelysines in the monitoring or prognosis of kidney cancer should be discussed.
Keywords: MMP-10; MMP-3; matrix metalloproteinase; renal carcinoma; stromelysin.