MMP9 and malignant colon neoplasm: On the other hand, knockdown of LEF1 in colon cancer cells results in various effects on cellular processes such as (a) increased apoptosis compared to control cells in vitro, and reduced tumor growth compared to normal colon cancer cells in vivo, (b) reduced invasiveness via decreased MMP-2 and MMP-9 expression, and (c) changed expression of genes involved in regulation of expression of matrix metalloproteinases such as metallopeptidase 7 (MMP7, a Zn2+—dependent proteolytic enzyme) [43].