Secretion of cathepsin B by human gliomas in vitro

摘要: There is evidence from investigations of non-CNS neoplasms that secreted proteolytic enzymes may facilitate tumour invasion by partially degrading extracellular matrix (ECM). Among the which be involved are members cysteine proteinase superfamily and especially cathepsin B (CB). In present investigation we have studied CB in human gliomas vitro, concentrating particularly on secretion, as enzyme prime importance this context. We found vitro a latent zymogen, requiring activation. This has been confirmed gel chromatography indicated 42 kDa proenzyme proteolytically processed to an enzymatically active 29 molecule. The inactive, high molecular weight, stable at pH contrast activated low weight form rapidly loses activity pH. also measured secretion inhibitors (CPI), their presence would direct influence effective CB, all significant amounts CPI assessed papain inhibition. Our experiments suggest number factors regulation glioma-derived activity. These include: rate pro-CB, activation, destabilization neutral inhibitors.