Matrix metalloproteinase 2 (MMP-2) immunoreactive protein is associated with poor grade and survival in brain neoplasms

Matrix metalloproteinases play an important role in the invasion of tumor c ells and the progression of cancer. The 72 kDa type IV collagenase, a matri x metalloproteinase 2 (MMP-2) has been shown to contribute to the invasion and metastasis in diverse malignant neoplasms. Object. To elaborate the potential role of MMP-2 in brain tumor invasion we studied the expression and localization of this enzyme protein in 101 brai n tumors representing different types of brain neoplasms. For the first tim e, we also correlated the expression of MMP-2 protein to patient survival. Methods. Using immunohistochemistry and a monoclonal antibody specific for MMP-2 we found that MMP-2 protein was primarily localized in tumor cells an d vasculature cells as well as inflammatory cells. The expression of MMP-2 was absent or negligible in benign tumors (pilocytic astrocytoma and mening ioma). Thirty-three percent (6/18) of astrocytomas, 38% (3/8) of anaplastic astrocytomas, 14% (1/7) of anaplastic oligodendrogliomas, 54% (19/35) of g lioblastomas and 100% (6/6) of metastatic brain tumors were positive for MM P-2. A correlation between MMP-2 expression and survival was found in malig nant brain tumors. The mean survival of patients with an MMP-2 negative tum or was 36 months, when it was only 7-14 months in patients with an MMP-2 po sitive tumor. Conclusions. Our data suggest that MMP-2 is associated with histological ma lignancy and poor survival in brain tumors.