The opposing role of ZEB1 over EMT in KRAS- and BRAF-mutant CRC was validated through the mRNA assessment of epithelial—E-cadherin (CDH1), tight junction protein ZO-3 (TJP3), occludin (OCLN), claudin-1 (CLDN1)—and mesenchymal—vimentin (VIM) and fibronectin III domain-containing protein 4 (FNDC4)—genes in LS174T and RKO cells stably interfered with an shRNA against ZEB1 or an shRNA control (Figure 6G; ref. 54). This evidence concerns the gene CLDN1 and colorectal carcinoma.