Objective: To study the expression of 11 cancer-testis (CT) genes and autologous humoral immune response to NY-ESO-1 in gastric carcinoma in China to provide some data for developing a vaccine against this cancer.
Methods: Pathology tests were conducted in 101 gastric carcinoma samples, including tumor tissue and paired adjacent normal non-tumor tissue. Reverse transcription-polymerase chain reaction (RT-PCR) was used to test for 11 CT antigen gene expression and ELISA for autologous humoral immune response to NY-ESO-1. The antigen of NY-ESO-1 was also detected in tumor tissues by mAb E978 in IHC.
Results: About 74.3% of the samples expressed at least one CT antigen, and the most frequently expressed one was MAGE-3 (41.6%). Twelve out of the 101 samples (11.9%) were found to be NY-ESO-1 mRNA positive. Simultaneously, autologous humoral immune response to NY-ESO-1 was detected in 6 of 12 NY-ESO-1 mRNA positive patients.
Conclusion: Multiple CT genes were expressed in gastric cancer samples. MAGE-3, SSX-1, SSX-4, NY-ESO-1/LAGE-1, and MAGE-1 can be chosen as candidate antigens for cancer vaccines due to their higher expression rate. The potential of a multivalent CT antigen vaccine, including NY-ESO-1 and MAGE-3 along with other CT antigens, should be evaluated in patients with gastric cancer.