Matrix metalloproteinases and proangiogenic factors in testicular germ cell tumors

Testicular cancer is the most frequent solid tumor in young male adults and a disease with elusive pathogenesis. The purpose of this study was to determine the role of matrix metalloproteinases and angiogenic factors in the pathogenesis of testicular germ cell tumors (GCTs).

Between 2003 and 2006 we measured the serum levels of matrix metalloproteinase 2 (MMP-2), matrix metalloproteinase 9 (MMP-9), tissue inhibitor of matrix metalloproteinase 2 (TIMP-2), vascular endothelial growth factor A (VEGF-A), basic fibroblast growth factor (bFGF), platelet derived growth factor BB (PDGF-BB) and angiopoietin 2 (Ang-2) in 50 patients with testicular GCTs, at baseline, one month after the completion of the second cycle of chemotherapy and one year after the completion of chemotherapy, and in 16 male age-matched controls at baseline.

At baseline, mean TIMP-2 value was lower in patients than controls, mean MMP-2/TIMP-2 ratio was higher in patients than controls and MMP9/TIMP-2 ratio was also higher. Ang-2 value was higher in patients than controls and bFGF value was also higher. Comparisons of the same parameters were also made among the 3 consecutive serum samples of the patients. All parameters normalized after chemotherapy except Ang-2 which remained elevated.

The present study supports the hypothesis that tumor invasion and angiogenesis play a role in testicular GCTs pathogenesis. Also an interesting hypothesis was formed, concerning the role of elevated levels of Ang-2 found in testicular GCTs patients in the pathogenesis of the increased long term cardiovascular morbidity of these patients. Larger prospective studies are needed to confirm our results.