SOX2 and esophageal squamous cell carcinoma: ESCC related genes were mostly found with amplified gene copy number, i.e. TP53, SOX2, EGFR, MYC, CCND1, CDKN2A, NOTCH1, BRCA1, NFE2L2, etc. While only TP53 and NFE2L2 were found in SNAs (Fig. 5).