DKK1 and esophageal squamous cell carcinoma: The correlation between the ratios of tumor lesions stained with DKK1 and FOXM1 was confirmed (Fig. 7B), namely an ESCC tumor lesion which highly expressed DKK1 was also positive for FOXM1, and a tumor lesion which did not express DKK1 was negative for FOXM1 (Fig. 7C).