APOPTOSIS IN PROSTATIC ADENOCARCINOMAS - A STUDY OF RELATIONSHIP TO KI-67 AND BCL-2 PROTEIN EXPRESSION

Background: Tissue samples from patients with prostatic adenocarcinoma (PCA) were examined for relationship between apoptosis and expression of Ki-67 and bcl-2 protein. Materials and Methods: Prostatic tissue w as obtained from 29 prostatic cancer patients with no prior therapy. T he number of apoptotic cells (apoptotic index; AI) and the percentage of Ki-67 stained cells (Ki-67 labeling index; LI) were compared with t he expression of bcl-2 which was evaluated by the proportion and inten sity of tumor cell immunostaining. Results: Both AI and LI of moderate ly and poorly differentiated PCAs were significantly higher than those of well differentiated PCAs. There was a significant correlation betw een AI and LI. Bcl-2 protein was expressed less in moderately and poor ly differentiated PCAs than in well differentiated PCAs. Moreover, the re was no correlation between the bcl-2 protein expression and the AI. Conclusions: The results suggest that, in PCAs, the degree of apoptos is is correlated with the cellular proliferation, and that expression of bcl-2 protein is not a critical factor that determines the degree o f apoptosis.