WTAP and esophageal squamous cell carcinoma: The expression levels of m6A “writers” (METTL3 and WTAP) and “readers” (i.e., IGF2BP3, YTHDF1, HNRNPA2B1 and HNRNPC) in ESCC were significantly higher than those in normal tissues, and elevated expression levels of 2 genes (METTL3 and IGF2BP3) have been reported to be an independent prognostic factor for ESCC patients (26, 27); other genes have not been studied.