Expression of 92-kDa type IV collagenase correlates with angiogenic markers and poor survival in head and neck squamous cell carcinoma

MMP-9, which degrades extracellular matrix, is believed to play a crucial r ole in tumor invasion and metastasis. Angiogenesis is also perceived as an important step in tumor growth and metastasis. The aim of this study was to investigate the expression of MMP-9 in tumor samples of HNSCC patients and to study a possible correlation to angiogenic markers. Cryostat sections o f 52 HNSCC tumors were immunostained for MMP-9, bFGF and VEGF using a stand ard streptavidin-biotin complex procedure for light microscopic investigati on. Microvessel density (MVD) was determined by staining of endothelial cel ls immunohistochemically using anti-vWF; monoclonal antibody. MMP-9 positiv e staining was detected in 27/52 (52%) of the tumors. MMP-9 immunoreactivit y did not con elate with the main clinicopathological characteristics of th e patients (localisation, T-stage, N-stage, histological grading), but corr elated with worse survival of the patients. MMP-9 negative tumors showed a significant lower mean MVD pet microscopic field than MMP-9 positive tumors (p<0.001). There was a significant association of MMP-9 and VEGF; expressi on (p<0.05). The presence of MMP-9 in HNSCC cancer and the positive correla tion with MVD and VEGF; expression supports the theory that MMP-9 functions as a regulator of tumor angiogenesis supporting endothelial cell invasion. MMP-9 and VEGF might act co-operatively in the process of neovascularizati on in human head and neck cancer.