CELL-PROLIFERATION IN PROSTATIC-CARCINOMA - COMPARATIVE-ANALYSIS OF KI-67, MIB-1 AND PCNA

Antibodies to assess the proliferative index of tumours are being incr easingly employed together with established markers for prognostic eva luation. This study set out to compare three cell proliferation marker s, Ki-67, MIB-1 and PCNA, utilizing a semiquantitative method of asses sment, in 20 human prostatic carcinomas. The streptavidin-biotin immun ostaining system was used for the monoclonal antibodies MIB-1 and PCNA and an indirect immunoperoxidase assay for the monoclonal antibody Ki -67. Significant correlations were found between the expression of Ki- 67 in frozen tissues and MIB-1 in formal saline-fixed wax-embedded tis sues (p = 0.0003); between Ki-67 and PCNA expression in Bouin's-fixed tissues (p less than or equal to 0.0001); and MIB-1 (formalin-saline-f ixed tissues) and PCNA (Bouin's-fixed tissues) (p less than or equal t o 0.0001). A more intense nuclear staining pattern with less heterogen eity was observed for MIB-1 compared with PCNA, suggesting the antibod y of choice, on formal saline-fixed tissues, is MIB-1, which closely c orrelated with Ki-67, a marker we have previously shown to be of progn ostic value in prostatic carcinoma.