We treated radioresistant primary ESCC cells (PDC-4 and PDC-5) and radioresistant ESCC cell lines (KYSE150R and KYSE450R) with IR or STAT1 silence and found that silencing STAT1 expression significantly increased the radiosensitivity (Supplementary Fig. S6). This evidence concerns the gene PDC and esophageal squamous cell carcinoma.