c-Src-induced caspase 8 phosphorylation was required for epithelial–mesenchymal transition (EMT) in lung adenocarcinoma cell lines. (A, B) Immunoblotting analysis of caspase 8 and c-Src in the mesenchymal-like (A) (A549, H1299, H2030, H23, H2405, H647, and H838) and epithelial-like (B) (H522, H1395, H1473, H1573, H920, and H1650) lung adenocarcinoma cell lines plated onto fibronectin for 5 days. (C) Phase contrast microscopy of A549 + control/c-Src/caspase 8 short hairpin RNA (shRNA) plated on dish coated with fibronectin over a 5-day period. Scale bars: 50 μm. (D) Immunoblotting analysis of p-Casp8, p-Src, caspase 8, c-Src, vimentin, E-cadherin, and β-actin in the A549 cells with control/c-Src/caspase 8 shRNA and H522 cells plated onto fibronectin at indicated times. *p < 0.05.