To identify whether the cancer cell methylation directly mediates KCNMA1 expression, we treated the two cell lines (i.e., MGC-803 and BGC-823) with the demethylation agent, 5-Aza-2′-deoxycytidine (5-Aza; Sigma-Aldrich), for 72 h. This evidence concerns the gene KCNMA1 and cancer.