It was found that the expression of GKN2 was significantly higher in paracancerous tissue and distal gastric mucosa, but the expression was significantly lower in gastric cancer tissue than that in paracancerous tissue and distal gastric mucosa, indicating that GKN2 might play a role as a candidate tumor suppressor gene in gastric carcinogenesis and thus downregulate expression in gastric cancer. The gene discussed is GKN2; the disease is neoplasm.