Abstract: Objective: To study the different expression and clinical significance of PTEN and p38MAPK in benign and malignant prostatic lesions. Methods: SABC immunohistochemical analysis was used to determine the expression levels of PTEN and p38 in 20 cases of benign prostatic hyperplasia(BPH),20 cases of prostatic intraepithelial neoplasia(PIN) and 46 cases of prostatic carcinoma (PC). Results: Expression of PTEN was the highest in BPH and significantly higher in PIN compared to PC (P<0.01). Expression of p38 was the highest in PC and significantly higher in PIN compared to BPH(P<0.05).PTEN protein expression in prostatic carcinoma was negatively correlated with tumor stage, and histological grade(r=-0.352,-0.653,P<0.05)；while p38 expression was positively correlated with the above features(r=0.298,0.596,P<0.05).There was a negative correlation between PTEN and p38 expression(r=-0.602,P<0.01)．Conclusions: Low PTEN protein expression and elevated activation of p38 are involved in the malignant transformation of prostatic epithelium and may play a great role in the genesis and development of prostatic tumor.

Key words: PTEN, p38MAPK, prostatic carcinoma, benign prostatic hyperplasia, prostatic intraepithelial neoplasia