The human gastric adenocarcinoma cell line AGS responded to IL-21 by increasing the production of MMP-2 and MMP-9 in a NF-kB-dependent fashion and treatment of H. pylori-infected gastric explants with an antibody against IL-21 decreased the production of epithelial cell-derived MMP-2 and MMP-9 [18]. This evidence concerns the gene MMP9 and gastric adenocarcinoma.