bcl-2 protein expression in endometrial carcinoma: the lack of correlation with p53

bcl-2 expression was examined on paraffin-embedded specimens in proliferative, hyperplastic, and neoplastic human endometrium by immunohistochemistry. The results of bcl-2 immunostaining in endometrial carcinomas were compared with clinicopathological indicators as well as with p53 accumulation. The streptavidin-peroxidase detection system was used and the intensity and the distribution of immunostaining was evaluated semiquantitatively by counting H-score values. Expression of the bcl-2 protein was found in 2 out of 5 cases of proliferative endometrium (mean H-score 0.4, range 0.35-0.45), 4 out of 5 cases of simple hyperplasia (mean H-score 1.23; range 1.0-1.4), 4 out of 5 cases of complex hyperplasia (mean H-score 1.1; range 0.7-1.2) and in 7 out of 25 cases of endometrial carcinoma (mean H-score 0.48; range 0.35-0.65). All bcl-2 positive slides were obtained from patients who had endometrial cancer and who were in the early (stage I due to FIGO) clinical stage of the disease. bcl-2 expression was not related to age, surgical stage or histopathological features, and neither was there an inverse correlation between bcl-2 immunostaining and p53 expression reported in the study of neoplastic endometrium. Our data indicate that mechanisms other than p53 may play a role in the regulation of bcl-2 expression in endometrial carcinomas.