MMP7 and colorectal cancer: MMP-7 is secreted specifically by epithelial cells [3] and its over-expression has been observed in many tumor types such as colorectal cancer [4–7], epidermolysisbullosa associated skin cancer [8, 9], bladder cancer [10], gastric cancers [3, 11], pancreatic cancer [12] and esophageal cancer [13, 14].