Increased expression of elongation factor-1α is significantly correlated with poor prognosis of human prostate cancer

Objective. Overexpression of elongation factor-1 alpha (EF-1 alpha) has been demonstrated to be related to increased cell proliferation, oncogenic transformation and delayed cell senescence. The purpose of this study was to determine whether EF-1 alpha expression affects the progression of prostate cancer (PCa), and whether it can be used as a prognostic marker for PCa. Material and methods. EF-1 alpha was evaluated by immunostaining in paraffin-embedded specimens of prostates obtained from 80 patients with PCa. Correlations of EF-1 alpha with patients' ages, Gleason scores, American Joint Committee on Cancer (AJCC) stages, International Union Against Cancer (UICC) stages, preoperative prostate-specific antigen (PSA) concentrations and PSA failure were evaluated. Survival in all patients was analysed to evaluate the influence of EF-1 alpha expression in cancer progression using Kaplan-Meier and multivariate Cox regression analysis. Results. The positive expression rate of EF-1 alpha in PCa tissues [64/80 (80.0%)] was significantly higher than that in normal prostate tissues [1/20 (5.0%)] (p < 0.001). Increased immunostaining of EF-1 alpha was a significant predictor of distant metastasis-free survival [hazard ratio (HR) 0.386, 95% confidence interval (CI) 0.032-2.519, p = 0.003] and overall survival (HR 0.305, 95% CI 0.091-0.872, p = 0.005). In multivariate analysis including competing biological variables, EF-1 alpha expression was still significantly linked to distant metastasis-free survival (HR 0.216, 95% CI 0.042-0.876, p = 0.015) and overall survival (HR 0.395, 95% CI 0.116-0.798, p = 0.008). Conclusion. These findings provide convincing evidence for the first time that EF-1 alpha correlates closely with the survival of patients with PCa and may be a novel prognostic marker.