In this study, seven genes (SLCO2A1, SHISA2, SERPINE1, SMPD3, GPC3, CRABP2, C1QTNF5) were used for the construction of OE_score, among which SLCO2A1, SERPINE1, CRABP2, and GPC3 were reported to be associated with gastric cancer (41–44), and play an important role in the occurrence and development of gastric cancer. This evidence concerns the gene CRABP2 and gastric cancer.