 Within gastric cancer cells, galanin has been found to have a tumor suppressive role, but hypermethylation has been shown to stop its tumor suppressive properties.Galanin is a peptide consisting of a chain of 29 amino acids (30 amino acids in humans) produced from the cleavage of a 123-amino acid protein known as prepro galanin, which is encoded by the "GAL" gene.The sequence of this gene is highly conserved among mammals, showing over 85% homology between rat, mouse, porcine, bovine, and human sequences.