As shown in Figure 3A, expression of the hypermethylated genes (VSIG10L, ST6GALNAC1, SCNN1B, PRSS27, PPP1R3C, KRT4, KLK13, KLK11, IL1RN, GPX3, EHD3 and CRABP2) in tumor tissues was lower than that of the corresponding genes in normal esophageal epithelial tissues. This evidence concerns the gene KRT4 and neoplasm.