To determine the role of mRNA m5C modification in ESCC, we evaluated the expression levels of two major mRNA m5C methyltransferases NSUN2 and NSUN6 in an ESCC cohort (n = 215; Supplementary Table 1) from Sun Yat-sen University Cancer Center (SYSUCC) using qRT-PCR. This evidence concerns the gene NSUN6 and esophageal squamous cell carcinoma.