SOX2 and esophageal squamous cell carcinoma: Somatic copy-number alterations (SCNA) analysis also demonstrates similarities and differences between ESCC and EAC, with VEGFA, ERBB2, GATA6 and CCNE1 amplified in EAC but not in ESCC, and SOX2, TERT, FGFR1, MDM2, and NKX2-1 amplified in ESCC but not in EAC [44].