Amplifications of CCND1, SOX2, and TP63 are recurrent in ESCC, whereas ERBB2, VEGFA, GATA4, and GATA6 are preferentially amplified in EAC (The Cancer Genome Atlas Research Network, 2017; Jiang et al., 2023). This evidence concerns the gene SOX2 and esophageal squamous cell carcinoma.