Since the public database results show that the expression of DKK1 and FOXM1 are highly correlated in PDAC and ESCC, two PDAC lines (S2-CP8 and HPAF-II) and two ESCC cell lines (TE-5 and TE-8) were mainly used in this study. The gene discussed is FOXM1; the disease is esophageal squamous cell carcinoma.