SNAI1 and non-small cell lung carcinoma: Consistent with the mRNA alteration, treatment with TGF-β increased the protein levels of the mesenchymal proteins N-cadherin, vimentin, snail, and slug, whereas the protein levels of the epithelial marker E-cadherin decreased in the TGF-β-treated NSCLC but not in the normal MRC5 fibroblast cells.