Abstract: Objective To examine the expression and the biological specificity of cancer-testis antigens(CTA) SSX, NY-ESO-1 and MAGE-A1 in normal pancreatic tissues, chronic pancreatitis and pancreatic carcinoma. Methods The paraffin-embedded tissue specimens were selected，including 8 cases of normal pancreatic tissues, 15 cases of chronic pancreatitis and 52 cases of pancreatic carcinoma. The expression of SSX, NY-ESO-1 and MAGE-A1 in the above-mentioned tissue specimens were analyzed by SP immunohistochemical staining. Furthermore, the expression of the three CTA in the 52 specimens of pancreatic cancer were detected by Western blotting.Results Immunohistochemical staining results showed that SSX，NY-ESO-1 and MAGE-A1 were not expressed in normal pancreatic tissues and chronic pancreatitis. The positive expression rate of SSX, NY-ESO-1 and MAGE-A1 in 52 cases of pancreatic cancer were 48.08%, 7.69%, 5.77%, respectively. There were no significant correlationship between the positive expression of SSX, NY-ESO-1, MAGE-A1 and the age, gender of the patient, cancerization location among the 52 cases of pancreatic cancer (EM>P/EM> >0.05). The expression of SSX negatively correlated with the infiltration and metastasis of the tumor (EM>r /EM>=-0.306，EM>P /EM>=0.028 ). There were more than one types of CTA expression in 55.77% (29/52) of pancreatic cancer.Conclusion The expression rate of different types of CTA in pancreatic cancer was significantly different. The positive expression rate of SSX was the highest. There was a negative correlationship between the high expression of SSX and metastasis of the tumor in pancreatic cancer. The expression of CTA

Key words: Pancreatic cancer, CTA, SSX, NY-ESO-1, MAGE-A1, Immunohistochemistry, Human