Objective: To evaluate the significance of melanoma antigen (MAGE) gene expression in bladder transitional cell carcinoma (TCC).
Methods: MAGE-A1, A2, A3, A4 mRNA expression was detected by reverse transcription polymerase chain reaction (RT-PCR) in 3 clusters bladder TCC cells and 20 samples of bladder TCC patients (T(1) 7 samples, T(2) 5 samples, T(3) 6 samples, T(4) 2 samples, G(1) 1 samples, G(2) 11 samples, G(3) 8 samples). MAGE-A4 protein was detected by immunohistochemistry in 105 samples of bladder TCC patients (T(1) 35 samples, T(2) 12 samples, T(3) 26 samples, T(4) 13 samples, G(1) 13 samples, G(2) 44 samples, G(3) 48 samples).
Results: Three clusters bladder TCC cells had MAGE gene mRNA expression. In detection of MAGE mRNA of 20 samples of bladder TCC patients, 12 samples (60%) expressed MAGE-A1, 16 samples (80%) expressed MAGE-A2, 11 samples (55%) expressed MAGE-A3, 18 samples (90%) expressed MAGE-A4, 8 samples (40%) expressed all of MAGE-A1--A4. In 105 bladder TCC samples, 53 samples (50%) expressed MAGE-A4 protein. Strong expression (++ or +++) was significant higher in higher grade (13 samples/48 samples) or stage (14 samples/51 samples) than in lower grade (2 samples/57 samples) or stage (0 samples/35 samples).
Conclusion: MAGE gene highly expresses in bladder TCC. Bladder TCC of high grade or high stage has higher MAGE-A4 protein strong expression.