MMP9 and colorectal cancer: In the phase of adenoma development, increased expression of MMP-1, MMP-3, MMP-7, and MMP-9 was observed, and subsequently, at the stage of colorectal cancer invasion, other MMPs, including MMP-2, MMP-8, MMP-10, MMP-12, MMP-13, MMP14, and MMP-21 are activated and overexpressed [11].