Nuclear overexpression levels of MAGE-A3 predict poor prognosis in patients with prostate cancer.

Melanoma antigen gene A3 (MAGE-A3) is one of the most immunogenic cancer testis antigens and is common in various types of cancers. In this study, for the first time, we performed immunohistochemical analysis to evaluate the expression of MAGE-A3 in 153 prostate tissue samples including prostate cancer (PCa), benign prostatic hyperplasia (BPH), and high-grade prostatic intraepithelial neoplasia (HPIN). Increased both nuclear and cytoplasmic expression of MAGE-A3 was significantly found in PCa tissues compared with both HPIN and BPH tissues (nuclear expression at p = 0.011, and cytoplasmic expression at p = 0.034; for both comparisons p < 0.0001, respectively). A significant correlation was observed between higher nuclear and cytoplasmic expressions of MAGE-A3 with Gleason score (p < 0.0001 and 0.006, respectively). Increased expression of MAGE-A3 was associated with shorter biochemical recurrence-free survival (BCR-FS) and disease-free survival (DFS) of patients (p = 0.042 and = 0.0001, respectively). In multivariate analysis, nuclear expression of MAGE-A3 and Gleason score (≤7 vs >7) was independent predictors of the DFS (both; p = 0.019). Nuclear expression of MAGE-A3 was also significantly related to BCR-FS (p = 0.015). MAGE-A3 can be considered as a predictor for poor prognosis and an option for vaccine immunotherapy in patients with PCa.