This finding was intriguing in that the lower ZNF331 promoter methylation level in GC cases is inconsistent with previous reports that ZNF331 serves as a tumour suppressor gene that is hypermethylated and downregulated in several types of cancer tissues, including GC [14], colorectal cancer [15–17], and oesophageal squamous cell carcinoma [33]. This evidence concerns the gene ZNF331 and cancer.