Then, we identified the up-regulation of MUC1 mRNA and the MUC1-C protein in Eca9706 and KYSE410 after treatment with CCL21, and subsequent transwell assay confirmed that silencing MUC1 remarkably inhibited the migration and invasion of ESCC cell lines induced by CCL21 in vitro. This evidence concerns the gene CCL21 and esophageal squamous cell carcinoma.