ZSCAN18 and gastric cancer: Recently, hypermethylation in the promoter of ZSCAN18 has been identified in various types of cancers, such as esophageal cancer [4], renal cell carcinoma [5], cholangiocarcinoma [6, 7], colorectal cancer [8, 9], GC [9–11], hepatocellular carcinoma [11], and pancreatic cancer [9–11].