TGFB1 and non-small cell lung carcinoma: The clinical relevance of EMT and drug insensitivity comes from recent studies showing an association between epithelial markers and sensitivity to erlotinib in NSCLC cell lines [17]–[19], suggesting that EMT-type cells are resistant to erlotinib, however the role of signaling molecules in mediating the induction of EMT by TGF-β1 is lacking.