Prognostic and clinicopathological value of melanoma-associated antigen D4 in patients with glioma

The aim of the present study was to evaluate the clinical importance of melanoma-associated antigen D4 (MAGE-D4) expression in glioma, and to identify it as a valuable prognostic biomarker and therapeutic target. To achieve this, the expression of MAGE-D4 protein in 124 tumor tissues from patients with glioma was measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC), and the associations between MAGE-D4expression and clinicopathological factors were evaluated. The survival analysis demonstrated the significant prognostic value of MAGE-D4 in glioma using follow-up data. RT-qPCR and IHC analysis confirmed that MAGE-D4 mRNA and protein expression levels were significantly increased in glioma tissues compared with those in normal brain tissues. The present study demonstrated that the percentage of glioma tissues with high expression of MAGE-D4 mRNA was 67.74%, and the percentage positive for MAGE-D4 protein expression was 78.23%. All patients with high MAGE-D4 expression in cancerous tissues experienced significantly reduced median overall survival (OS; 18.00 vs. 33.29 months; P<0.001) and recurrence-free survival (RFS; 12.7 vs. 28.3 months; P<0.001) times compared with those with low MAGE-D4 expression. In the patients with lower grade glioma [World Health Organization (WHO), I-II], similar results were obtained for the OS (26.11 vs. 57.85 months; P=0.013) and RFS (22.7 vs. 55.3 months; P=0.010) times; however, in patients with high-grade glioma (WHO, III-IV), there were no significant differences between high and low MAGE-D4 expression levels with regard to OS and RFS times (P>0.05). Multivariate analysis indicated that high MAGE-D4 protein expression was an important independent prognostic factor for patients with glioma (hazard ratio, 2.384; P=0.005), and was significantly associated with higher grade glioma (P<0.001). These results indicated that MAGE-D4 may be a potential biomarker for glioma and an important prognostic factor for patients with new or recurring glioma.