MMP9 and cancer: The metastasis of cancer cells is typically accompanied by a decrease in expression levels of epithelial cell markers (e.g., E-cadherin) and an increase in expression of mesenchymal markers (e.g., N-cadherin, ZEB2, ZEB1, Vimentin, Slug and Twist, among others)22,23, angiogenesis-related factors (e.g., vascular endothelial growth factor (VEGF))24, and matrix metalloproteinases (e.g., MMP-9 and MMP-2)25.