Expression of melanoma antigen-encoding gene-1 predicts lymph node involvement in early gastric carcinomas.

Our previous study suggested that melanoma antigen-encoding gene-1 may be activated in gastric carcinomas when the tumors develop or invade. In the present work we studied the gene as a preoperative indicator of lymph node involvement in early gastric carcinoma. We used a reverse transcription-polymerase chain reaction to analyze expression of the gene in 47 endoscopic biopsy specimens from early gastric carcinomas. Relationships between gene expression and histopathologic findings were analyzed statistically. Eight of 47 tumor samples (17.0%) expressed the gene. The gene was not expressed in adjacent nontumor samples from carcinoma patients or in tissues from patients with benign gastric diseases. Gene expression correlated with infiltrative tumor growth in contrast to tumors with expansive growth patterns (P = 0.018). Gene expression also correlated with expression of platelet-derived growth factor-A (P < 0.001). MAGE-1 gene expression in biopsy specimens was a preoperative indicator of nodal involvement (P = 0.013). In conclusion, melanoma antigen-encoding gene-1 expression in biopsy specimens from early gastric carcinoma may serve preoperatively as an indicator of lymph node involvement.