Expression and prognostic significance of ELL-associated factor 2 in human prostate cancer

ELL-associated factor 2 (EAF2) is an androgen-regulated tumor suppressor in the prostate. The purpose of this study was to investigate the expression of EAF2 protein in human prostate cancer specimens along with BPH specimens as a control, and to evaluate potential association of EAF2 expression with clinical characteristics and overall survival of the prostate cancer patients. The expression of EAF2 was evaluated in 44 prostate cancer and 23 BPH tissue specimens using immunohistochemistry. The relationships of EAF2 expression with clinical characteristics and overall survival rates were analyzed by Chi-square test and Kaplan-Meier method. The immunostaining intensity of EAF2 in BPH specimens was significantly higher than that in prostate cancer (p < 0.05). EAF2 expression decreased significantly in high-grade and advanced-stage human prostate tumors and inversely correlated with PSA level, Gleason scores, bone metastasis and tumor stage. Importantly, loss of EAF2 expression was associated with a significant decrease in patient survival. Expression of EAF2 is decreased in prostate carcinogenesis, and EAF2 loss is associated with high-risk patients and poor survival.