CATHEPSIN-B, CATHEPSIN-L, AND CATHEPSIN-D ACTIVITIES IN COLORECTAL CARCINOMAS - RELATIONSHIP WITH CLINICOPATHOLOGICAL PARAMETERS

Cathepsins, which are secreted by tumour and/or stromal cells, are tho ught to be involved in the degradative processes of tumour invasion an d metastasis. The purpose of our study was to compare the cytosolic co ntent of cathepsin B, L, and D in a series of matched malignant and ad jacent normal colorectal tissues. Further we attempted to correlate th ese different proteinase values to classical clinico-pathological prog nostic variables. Cathepsin B, L, and D activities were higher in tumo ur tissues than in normal mucosa (P < 10(-6), P < 0.004, P < 0.004, re spectively) with median tumour/normal ratios of 7.9, 5.9, and 1.4, res pectively. We found no difference in cathepsin B, L, and D activities either as a function of gender (except for cathepsin B values), age at time of surgery, tumour site, tumour differentiation, tumour stage (T NM or Astler-Coller staging system) or whether or not we found a mucin ous component. Based on our data, cathepsin B seems to be the most dis criminant parameter of the three proteinases that we studied, suggesti ng that cathepsin B expression may be of critical value in the progres sion of colorectal cancers.