Expression of MMP-7 and MT1-MMP in oral squamous cell carcinoma as predictive indicator for tumor invasion and prognosis

Background: Squamous cell carcinoma of the oral cavity is a highly invasive neoplasm that spreads locally and metastasizes to regional lymph nodes. This process involves multiple proteolytic enzymes including matrilysin (MMP‐7) and membrane type I‐matrix metalloproteinase (MT1‐MMP). This study was designed to explore the association between MMP‐7 and MT1‐MMP in the invasiveness and prognosis of oral squamous cell carcinoma (OSCC). Methods: About 4‐μM, formalin‐fixed, paraffin‐embedded tissue sections from 69 patients with OSCC were immunohistochemically studied using specific antibodies against MMP‐7 and MT1‐MMP proteins. Immunostaining was semiquantitatively scored, and results were correlated with histologic and clinical variables including clinical behavior and survival. Results: MMP‐7 was observed only in cancer cells, and MT1‐MMP in both tumoral tissue and stroma. MMP‐7 expression was significantly correlated with lymph node metastasis (P = 0.03; RR = 3.2). MT1‐MMP showed a significant association with TIMP‐2 (in N+ cases) and p53 expression (P = 0.01). MMP‐7 and MT1‐MMP displayed a survival relevance, and in multivariate analysis they were independent prognostic indicators, particularly in neck node‐positive cases.