Objective: To investigate the relationship between six-transmembrane epithelial antigen of the prostate (STEAP) expression and the histologic grading of prostatic carcinoma (PCa).
Methods: Different prostatic tissues and non-prostatic tumors, 131 cases of PCa, 164 cases of benign prostate hyperplasia (BPH), and 56 cases of non-prostatic malignancies, were analyzed for the expression of STEAP by using STEAP monoclonal antibody and SP immunohistochemical staining. The positive area unit (PU) was introduced to describe the intensity of STEAP expression.
Results: The prostatic tissues of all but 3 cases of PCa and 5 cases of BPH were stained positively, while all of the non-prostatic tumors were stained negatively. There was a significant negative correlation between the STEAP expression and the histologic grading of PCa.
Conclusion: STEAP can be a prognostic marker of PCa and a potential therapeutic target in PCa.