Matrix metalloproteinase-9 expression correlates with prognosis and involved in ovarian cancer cell invasion.

PURPOSE: One of the most important characteristics of ovarian cancer is invasion and metastasis. Matrix metalloproteinases (MMPs) are known to play an important role in cancer cell invasion by mediating the degradation of extracellular matrix (ECM). The activities of MMPs are regulated by tissue inhibitors of metalloproteinases (TIMPs). In this study, we investigated the clinical significance of MMP-2, -7 and -9 and TIMP-1, -2 and -3 expression and MMP-9 functional role in cell invasion and adhesion in ovarian cancer. METHODS: RT-PCR was used to determine mRNA expression of MMP-2, -7 and -9 and TIMP-1, -2 and -3 in ovarian tissues; ELISA was used to detect the serum level of MMP-9; RNA interference (RNAi) was performed to determine the function of MMP-9 in cell invasion and adhesion in ovarian cancer cells. RESULTS: mRNA expression of MMP-2, MMP-7, MMP-9, TIMP-2 and TIMP-3 and serum level of MMP-9 were significantly high in patients with ovarian cancer. MMP-9 expression was significantly high in patients with advanced ovarian cancer and correlated with poor prognosis. The ability of cells for invasion and adhesion was significantly reduced by treatment of cells with MMP-9 siRNA. CONCLUSIONS: Our results suggest that MMP-9 is a potential prognostic factor for ovarian cancer and could be a novel treatment target in ovarian cancer patients.