LEVELS OF PLASMA CYSTEINE-PROTEINASE ACTIVITY IN BLADDER-CANCER PATIENTS

Plasma activity of a Cathepsin B like (CB) cystine protease was evalua ted employing a chromogenic assay in citrated plasma samples of 21 pat ients with transitional bladder cancer (TBC), and 36 healthy blood don ors. The median value of total CB activity was significantly higher in the group of patients bearing bladder carcinoma (103.4 mU/ml) as comp ared to the control group (77.7 mU/ml). 57% of patients showed high va lues of total CB while only 25% of the controls showed values over the cut-off levels (97.0 mU/ml). When the proenzyme (pro-CB) was analyzed , the median value was also significantly higher in the TBC patients ( 42.2 mU/ml) as compared to the control group (20.6 mU/ml). While 62% o f TBC group showed values over pro-CB cut-off level (35.0 mU/ml) only 31% of controls did so. Total CB median value from other 29 patients s uccesfully treated from TBC without evidence of disease at the moment of blood colection was near the cut-off (97.6 mU/ml) while pro-CB medi an values were lower than the cut-off levels (33.2 mU/ml).