Upregulation of erythropoietin receptor in human prostate carcinoma and high-grade prostatic intraepithelial neoplasia.

The aim of the present study was to investigate the differential expression of erythropoietin receptor (EPOR) in prostate carcinoma (PCa), high-grade prostatic intraepithelial neoplasia (PIN), prostatic hyperplasia (BPH) lesions and normal prostatic tissues by immunohistochemistry; and to test the hypothesis that upregulation of EPOR is a specific event for prostate carcinogenesis. An immunohistochemical analysis of EPOR was performed on 30 PCa, 50 BPH with/without inflammation lesions and 30 normal prostatic tissue samples. EPOR staining was quantitated and classified into normal expression and overexpression. Totally 16 high-grade PIN lesions were found in this study. Overexpression of EPOR was shown only in PCa and high-grade PIN. Statistical analysis demonstrated that higher median EPOR staining score of PCa and high-grade PIN in comparison with BPH (P < 0.05) and higher median EPOR staining score of PCa compared with high-grade PIN (P < 0.05). Our data demonstrate that upregulation of EPOR is not uncommon for PCa and upregulated EPOR in high-grade PIN suggests upregulation of EPOR is an early event for prostate carcinogenesis. The role of upregulated EPOR and possibly enhanced EPOR signaling in prostate carcinogenesis warrants further studying.