Studies conducted in vivo with tumor xenografts of A549 parental and erlotinib-resistant cells (Figure 3C) demonstrated the sustained overexpression of p-p38 and total p38 kinase, as well as overexpression of the mesenchymal marker vimentin and the EMT-associated transcription factor brachyury (Figure 3D). This evidence concerns the gene TBX1 and neoplasm.