Silencing of EPAS1 caused a significant reduction of clonogenic capacity of ESCC cells (KYSE70−EPAS1 and KYSE150−EPAS1) in comparison to the controls (KYSE70+Scr and KYSE150+Scr) and nontransfected wild-type (KYSE70wildtype and KYSE150wildtype) ESCC cells (Figures 6C,D). This evidence concerns the gene EPAS1 and esophageal squamous cell carcinoma.