H2AX and esophageal squamous cell carcinoma: Serine 139 on H2AX is phosphorylated and modified to form phosphorylated H2AX, namely, γH2AX, which is a marker of DNA double-strand breaks and can reflect the degree of DNA damage and repair.​ Our results demonstrated that the upregulation of miR-4443 decreased γH2AX expression in ESCC cells at 24 h after irradiation, whereas the downregulation of miR-4443 increased γH2AX expression.