Unlike what happens with other peptides (e.g., substance P, neurotensin), which exclusively exert a proliferative action on tumor cells [9,10], GAL exerts this proliferative action, but also suppresses the development of certain types of cancer (e.g., neuroblastoma, head and neck squamous cell carcinoma, gastric cancer) [11,12,13]. This evidence concerns the gene GAL and gastric cancer.