KDM4C and esophageal squamous cell carcinoma: In previous studies, GASC1 was shown to be a regulator of stemness in CSCs of ESCC via pluripotency-associated genes (PAGs) promoter demethylation, such as NOTCH1 and SOX2 [14, 15], and the high level of GASC1 was closely associated with poor survival of ESCC patients [14–16].