ISSN:
1573-7276
Keywords:
cysteine proteases
;
extracellular matrix
;
glioblastoma multiforme
;
invasion
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Degradation of the extracellular matrix is a prerequisite for acquisition of the invasive phenotype. Several proteinases released by invading tumor cells appear to participate in the focal degradation of extracellular matrix proteins. Using an enzyme-linked immunosorbent assay, enzymatic assays, Western and Nothern blotting techniques, we determined whether increased levels of the cysteine protease cathepsin B correlated with the progression and invasion of human gliomas. The amount of cathepsin B activity and protein content were highest in glioblastomas, lower in anaplastic astrocytomas and lowest in normal brain tissue and low-grade gliomas. There were significantly higher amounts of Mr 25 000 and 26 000 bands in glioblastoma and anaplastic astrocytoma than in normal brain and low-grade glioma tissue extracts as determined by Western blotting with anti-cathepsin antibodies. In addition, cathepsin B transcripts were overexpressed in anaplastic astrocytoma (about two- to three-fold), in glioblastoma (about eight- to 10-fold), compared with normal brain tissue and low-grade glioma. Immunobistochemical staining for cathepsin B showed intense immunoreactivity in tumor and endothelial cells of glioblastomas and anaplastic astrocytomas but only weak immunoreactivity in low-grade glioma and normal brain tissues. Therefore, we conclude that cathepsin B expression is greatest in highly malignant astrocytomas, especially in glioblastomas, and is correlated with the malignant progression of astrocytomas.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00144018
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