Background/aims: There is still little information on the function of GAGE gene in stomach cancer except for cancer-specific gene expression recognized by autologous T lymphocytes. This study attempted to detect GAGE expression in stomach cancer to evaluate its clinical implication as a tumor marker or prognosticator as well as to find the candidate for immunotherapy.
Methodology: Tumor samples from 60 patients and gastric juices from 18 patients with gastric cancer were studied by using RT-PCR with common primer. In-situ RT-PCR and southern blotting were performed to confirm the RT-PCR products.
Results: No expression of GAGE was observed in non-neoplastic juices and tissues. Fifteen out of 60 tumor tissues expressed GAGE (25.0%) mRNA, of which 13 cases (86.7%) were intestinal type and only 2 cases (13.3%) were diffuse type. In gastric juice, 22.2% (4/18) showed mRNA expression, all of which were intestinal type. GAGE expressions in both cancer tissues and gastric juices had a significant tendency to be higher by stage and lymph node metastasis (p<0.05). However, they did not show a significant relationship with tumor cell differentiation and vascular and perineural invasions.
Conclusions: These results suggest that GAGE gene might have an important role in the development and progression of intestinal type of stomach cancer and the detection of GAGE mRNA may be eligible to the panel of molecular markers for aggressive behavior as well as being useful to a molecule for cancer-specific immunotherapy.