IMMUNOHISTOCHEMICAL STUDIES OF PROLIFERATING CELL NUCLEAR ANTIGEN ANDCATHEPSIN-D IN TRANSITIONAL-CELL CARCINOMA OF THE URINARY-BLADDER

Immunohistochemical staining for proliferating cell nuclear antigen (P CNA) and cathepsin D was performed on 60 transitional cell carcinoma ( TCC) specimens from 60 patients with bladder cancer. The percentage of PCNA-positive cells (PCNA-labelling index) was determined by counting 500 or 1,000 cells, and cathepsin D expression was graded according t o the extent of immunoreactivity to anti-cathepsin D antibody. The PCN A-labelling index was significantly higher in high-grade and high-stag e tumors compared to that in low-grade and low-stage tumors. Cathepsin D was highly positive in grade-1 tumors. In contrast, 82% of grade-3 tumors and 76% of advanced tumors showed negative or low reactivity to anti-cathepsin D. Groups of high PCNA-labelling index and negative ca thepsin D had significantly poorer prognoses compared to those of the low PCNA group and cathepsin D highly positive group, respectively, in univariate analyses. However, neither of these two factors were indep endent prognostic factors in multivariate analyses. These results sugg est that the PCNA-labelling index and cathepsin D expression may indic ate the malignant potential of TCC and may be able to provide addition al information for predicting survival when stratifying for grade of b ladder cancer.