GAST and gastric cancer: Although gastrin was recognized as central in gastric NET development in humans (64) and rodents (65) from the mid-1980s, such tumors were not regarded as relevant to human gastric carcinomas because it was believed that human ECL cells could not transform into malignancies (116), Therefore, our group has mainly focused on neuroendocrine/ECL cell differentiation in human gastric cancers (55, 117, 118). However, a recent review by another group has focused on the central role of gastrin in gastric carcinogenesis (119).