[Increased expression of gelatinases A and B, matrilysin and TIMP-1 genes in human malignant gliomas ].

: Malignant glioma is a local invasive tumor in the central nervous system. The mRNA expression of five matrix metalloproteinases (MMPs) and two tissue inhibitors of metalloproteinases (TIMPs) was examined in surgical specimens of three brain tissues, two astrocytomas, four anaplastic astrocytomas and eleven glioblastomas, including recurrent one anaplastic astrocytoma and two glioblastomas. In the control brain tissues, mRNA expression was high for TIMP-2, low for gelatinase A and TIMP-1, and undetectable for gelatinase B, interstitial collagenase, stromelysin and matrilysin. Gelatinase B and TIMP-1 were concomitantly overexpressed in primary glioblastomas. In addition, the average expression level of gelatinase A increased 3.0 fold in astrocytomas and anaplastic astrocytomas and 6.0 fold in glioblastomas, compared to the brain tissues. Matrilysin was induced variably in more than half of the primary glioblastomas, and interstitial collagenase was slightly induced in some primary and recurrent glioblastomas. Stromelysin was characteristically not expressed in any gliomas, and the expression level of TIMP-2 did not significantly change in the gliomas. These results suggest that the concomitant increased expression of gelatinase A, gelatinase B and occasional matrilysin genes is associated with the malignancy of gliomas and accompanied by the increased expression of TIMP-1 gene.