Although matrilysin (MMP-7) is overexpressed in various malignancies, few studies have evaluated its role in epithelial ovarian cancer (EOC) invasion and metastasis. We report that the secretion of MMP-7 in EOC is stimulated significantly by vascular endothelial growth factor (VEGF) and interlukin-8 (IL-8). We also examined the in vivo expression of MMP-7 in EOC and its effects on the in vitro invasion and progelatinase activation. We report that MMP-7 is overexpressed in ovarian cancer cell lines and EOC surgical specimens. DOV13 cells incubated with active rhMMP-7 significantly increased cellular invasion and proMMP-2 activation. RhMMP-7 also showed the ability to activate proMMP-2 and proMMP-9 in immortalized ovarian epithelial cell (IOSE-29) conditioned medium. In addition, rhMMP-7 was able to activate progelatinase in a concentration-dependent manner in vitro. TIMP-2 or the generic MMP inhibitor-GM6001 inhibited both the activation of proMMP-2 and the increased invasion of DOV13 cells promoted by rhMMP-7. By incubation of MMP2-TIMP-2 complex with equal molar rhMMP-7, MMP-2 was dissociated from the complex and activated in a time-dependent manner, suggesting that TIMP-2 helps to keep the latency of MMP-2. TIMP-2 also showed inhibitory effects on the MMP-7 induced increase of gelatinolytic activity in DOV13 and IOSE-29 conditioned media. Epithelial ovarian cancer (EOC) has the highest mortality of all gynecological malignancies and is the 5th most common cancer in women in the United States. This year approximately 25,000 women will be newly diagnosed with ovarian cancer and 14,000 will die from this disease. 1,2 Unfortunately, at initial diagnosis 70 -75% of women with EOC present with widespread intraabdominal carcinomatosis, with the resultant 5-year survival approximating 15%. The diffuse spread of tumor cells throughout the peritoneal cavity and ultimate resistance to chemotherapy are responsible for the poor clinical outcome. 1,3 To provide urgently needed insights that may lead to early detection, prevention and effective intervention, it is important to understand the molecular events that support the survival and implantation of metastatic malignant ovarian epithelium. Protease activation and extracellular matrix (ECM) degradation are regarded as important steps that facilitate EOC invasion and metastasis. 4 Matrix metalloproteinases (MMPs) are a family of structurally related zinc-dependent endopeptidases that are frequently elevated in the tumor microenvironment and capable of degrading essentially all components of the ECM. 5,6 With the ability to degrade ECM proteins, MMPs expose cryptic sites within the matrix molecules that may facilitate tumor invasion and metastasis through the complicated interactions with other proteases, growth factors and cytokines. Matrix metalloproteinases are usually secreted in a latent (pro) form and are activated by the proteolytic removal of the NH 2 -terminal propeptide. Pro-MMP activation can be physically achieved by proteases belonging to the MMP family as well...

Vascular endothelial growth factor (VEGF) expression is elevated in primary ovarian tumors and metastases. We examined the effect of VEGF on epithelial ovarian cancer (EOC) in vitro invasion and migration and underlying mechanisms. Using the Matrigel invasion assay and colloidal gold phagokinetic track assay, we found that VEGF induced EOC DOV13 invasion and migration in a matrix metalloproteinase (MMP)-dependent manner. Using Western blotting, we show that VEGF, at 20-80 ng/ml, induced secretion of pro-MMP-7 and pro-MMP-9 and activation of pro-MMP-2 in DOV13 conditioned medium in a concentrationdependent manner. However, gelatinolytic activity and total MMP-7 protein in DOV13 conditioned medium reached the maximum upon VEGF treatment at 20-40 ng/ml and decreased at higher-concentration VEGF treatment (80 ng/ml), as shown by DQ-gelatin degradation assay and ELISA. In addition to the effect on MMP secretion/activation, VEGF stimulated secretion of TIMP-2; and blocking TIMP-2 activity by an anti-TIMP-2 MAb significantly increased VEGF (80 ng/ml)-induced DOV13 invasion (p < 0.05), suggesting that VEGF may regulate MMP-2 activity in DOV13 conditioned medium through TIMP-2. Using real-time PCR, we found that VEGF, at 20 ng/ml, significantly increased the expression of VEGFR-1 and VEGFR-2 by approximately 4-fold and 31-fold, respectively, compared to untreated control (p < 0.05). However, the inducing effect of VEGF on VEGFR-2 expression and the internal expression of VEGF121 in DOV13 cells decreased with increasing of VEGF concentration, suggesting the existence of a negative feedback regulatory mechanism. In summary, our results indicate that VEGF may regulate EOC invasion and migration through VEGFR-mediated secretion and activation of MMPs. ' 2005 Wiley-Liss, Inc.Key words: vascular endothelial growth factor; matrix metalloproteinase; gelatinase A/MMP-2; gelatinase B/MMP-9; matrilysin/MMP-7; membrane type 1 matrix metalloproteinase; tissue inhibitor of matrix metalloproteinase; epithelial ovarian cancer; tumor invasion; vascular endothelial growth factor receptor EOC is the leading cause of death among all gynecologic malignancies and the fifth most common cancer in women in the United States.1 At initial diagnosis, the majority of women are diagnosed with advanced-stage EOC, with a resultant poor prognosis because of widespread dissemination throughout the abdomen and pelvis.2,3 Therefore, understanding the mechanisms involved in EOC metastasis may significantly improve women's health care. EOC metastasis and the formation of malignant ascites require a coordinated series of events to support the survival and implantation of disseminated malignant ovarian epithelium. VEGF, also known as vascular permeability factor, has been found to be a potent mediator of those events.

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