In many cancers, EMT is controlled by a group of transcriptional repressors, including SNAIL, SLUG, TWIST, ZEB1, and ZEB2 (65), which downregulate the expression of E-cadherin and other epithelial cell–specific genes, and one or more of these repressors are HIF-regulated in many cancers (66–80). Here, SNAI2 is linked to cancer.