Tomita et al. [103] demonstrated that immunostaining of MMP-2 and MMP-9, as well as TIMP-1 and TIMP-2 increased gradually from tubular to villous adenomas, while in situ carcinomas showed a definite positive expression, concluding that the behavior of MMP-2, MMP-9 and TIMPs coincides with a multistep process of colonic tumorigenesis. Here, MMP9 is linked to villous adenoma.