EGF and esophageal squamous cell carcinoma: Our previous experiments on EMT in the human ESCC cell line Eca-109 have also shown the significant upregulation of cripto-1 (CR-1, CRGF, teratocarcinoma-derived growth factor 1, TDGF1), an epidermal growth factor-CR-1/FRL-1/cryptic (EGF/CFC) gene family member that appears to be associated with reprogramming differentiated tumor cells into cancer stem cells through inducing EMT [7, 8].