MAGE expressions mediated by demethylation of MAGE promoters induce progression of non-small cell lung cancer.

BACKGROUND

The MAGE gene encodes cancer/testis antigens that are recognized on melanoma cells by autologous cytolytic T lymphocytes. These genes are expressed in various tumor cells, but not in healthy tissues except for the testis and placenta. MAGE expression is known to be activated by promoter demethylation.

MATERIALS AND

METHODS

The expression of MAGE-A1 and -A3 and promoter methylation of MAGE-A1 and -A3 was investigated in 67 non-small cell lung cancer (NSCLC) specimens and their correlation with clinicopathological parameters was elucidated.

RESULTS

Expression of MAGE-A1 and -A3 was detected in 29.9% and 38.8% of the cases. Demethylation of MAGE-A1 and -A3 was detected in 41.8% and 46.3% of the cases. In 18 (of 20) cases, MAGE-A1 expression showed demethylation of MAGE-A1 and in 24 (of 26) cases MAGE-A3 expression showed demethylation of MAGE-A3. The patients with MAGE expression had a worse prognosis than those with no MAGE expression.

CONCLUSION

MAGE expression mediated by demethylation of MAGE promoters is associated with aggressive progression of NSCLC.