Considering the fact that GI tract is mainly constituted of epithelial cells and colon cancer has epithelial origin, we have generated transgenic mice ‘Tg-villin-MMP9 (TgM9)’ that constitutively expresses MMP9 under villin promoter (TgM9) [14, 15]. The gene discussed is MMP9; the disease is malignant colon neoplasm.