By examining different PDAC and ESCC cell lines, we confirmed that DKK1 is highly expressed in cell lines which highly expressed FOXM1 (S2-CP8, HPAF-II, TE-1, TE-5, and TE-8 cells) and that DKK1 expression was low in cell lines with low FOXM1 expression (Panc02.13, Capan-1, and TE-10 cells) at both the protein and mRNA levels (Fig. 1F, G). The gene discussed is FOXM1; the disease is esophageal squamous cell carcinoma.