Wong et al. found methylated sequences of ENG in both an ESCC cell line panel and clinical patient samples 24, while Jin et al. further supported that ENG promoter hypermethylation is a tissue-specific, frequent event in ESCC and shows a field defect as a potential marker for early monitoring and treatment by 5-aza-2'-deoxycytidine, which reverses methylation of ENG and reactivates its expression 25. This evidence concerns the gene ENG and esophageal squamous cell carcinoma.