Moreover, MMP-9 immunohistochemistry revealed: (1) a strong reactivity in neoplastic vessels of high-grade gliomas showing an inverse correlation with serum multimeric gelatinolytic activity; (2) a cytoplasmatic reactivity in meningiomas with a significantly increase in atypical meningioma compared with low-grade ones (p = 0.036); (3) a positive correlation between MMP-9 and Ki-67 (Sperman Rho coefficient r = 0.418 and p = 0.034).
67 cases of meningiomas, including 57 benign tumors (WHO grade I) and 10 non-benign tumors (WHO grade II and III), were collected, and expression of MIF and MMP9 in tissue microarray was evaluated immunohistochemically.
In conclusion, the differential expressions of extracellular matrix-related genes according to the histologic subtypes appear to be involved in biologic behavior and clinical outcome, and high matrix metalloproteinase 9 expression is associated with recurrences in rhabdoid meningiomas.
Furthermore, these observations demonstrate that the simultaneous RNAi-mediated targeting of cathepsin B and MMP-9 has potential application for the treatment of human meningiomas.