RESUMO
Objective To observe the expression change of melanoma-associated antigen(MAGE)-A9 in colorectal cancer (CRC)tissue and to explore its significance.Methods The samples in 23 cases of initially diagnosed CRC in the Affiliated Hospital of Nantong University from January 2006 to December 2008 were collected.The quantitative real-time(qRT)-PCR was adopted to detect MAGE-A9 mRNA expression in cancer tissue and corresponding paracancerous tissue.Its correlation with the clinicopatho-logical features and prognosis was analyzed.Results The positive rate of MAGE-A9 in CRC tissue was significantly higher than that in paracancerous normal tissue(P<0.05).MAGE-A9 protein expression in CRC was related to the clinicopathological features such as tumor differentiation degree(P=0.011),TNM stage(P=0.003),tumor infiltration depth(P=0.001)and lymph node me-tastasis(P=0.003).The survival analysis showed that the expression of MAGE-A9 was closely related to the prognosis of CRC pa-tients.Conclusion MAGE-A9 expression is increased in CRC tissue,suggesting the poor prognosis.