Abstract: Objective To study the expression of bcl-2,p53,P504S and 34βE12 proteins in patients with prostatic carcinoma and the relationship between these gene products and the pathogenesis of prostatic carcinoma.Methods Expression of bcl-2,p53,P504S and 34βE12 proteins in fifty-four cases of prostatic carcinoma and twenty cases of benign hyperplasia of prostate was determined with immunohistochemical SP assay.Results It was found that positive rates of bcl-2 and p53 in prostatic carcinoma were 44.4% and 33.3% respectively,both were not significantly higher than those in benign hyperplasia of prostate statistically,but a tendency of their increasing expression in prostatic carcinoma could be seen.The expression of bcl-2 in the group of poor differentiated was significantly higher than that in the well-differentiated group(P<0.05).When compared in terms of clinical stages,it was observed that bcl-2 expression at stage D was significantly higher than that at stage B or C(P<0.05).There existed a tendency of increase in p53 expression in prostatic carcinoma,but it was not significantly higher than that in benign hyperplasia of prostate.The tumor cells displayed positive reaction for P504S and negative for 34βE12.P504S can be used to differentiate the benign prostate gland from the prostatic carcinoma.Conclusion It is suggested that bcl-2 and P504S protein expressions increase in prostate carcinoma and is,to some extent,involved in the pathogenesis and development of the disease.It is important to use immunohistochemical staining for bcl-2,P504S and 34βE12 protein in the pathologic diagnosis of prostatic carcinoma.

Key words: prostatic carcinoma, immunohistochemistry, 34βE12, P504S