ABSTRACT
Proteinases and their inhibitors may play a role in the development and progression of many cancers. Several studies suggested that lysosomal proteinases cathepsin B, L, and D may be involved in the malignant progression of some human neoplastic diseases. In this study, we determined the levels of cathepsin H in human glioma progression and the significance of cathepsin H in glioma cell invasion. Levels of cathepsin H antigen were found to be significantly higher in glioblastomas and anaplastic astrocytoma when compared with normal brain tissue and low-grade gliomas. Western blotting confirmed the presence of authentic cathepsin H with a doublet at 27 and 25 kDa in normal brain tissue and tumor samples. However, the intensity of the band increased significantly in glioblastoma samples. Cathepsin H antibody inhibited the invasion of glioblastoma cell lines through Matrigel invasion assay. These data suggest that the tumor-specific increase in antigen may be a useful independent marker of tumor progression in central nervous system neoplasms.