The upregulated expression of COX-2 has been observed in numerous premalignant and malignant diseases, including colorectal adenoma, Barrett’s esophagus, colorectal cancer, gastric cancer, esophageal cancer, breast cancer, lung cancer, glioblastoma and so on (Wang and Dubois, 2006; Jiang et al., 2017; Wang D. et al., 2021). This evidence concerns the gene PTGS2 and gastric cancer.