NKX2-1 and lung adenocarcinoma: In summary, lung adenocarcinoma cells cultured in an embryonic lung medium lose their epithelial morphology, reduce the expression of the adenocarcinoma markers NKX2-1 and SFTPs, decrease proliferation, downregulate the expression of the OSKM transcription factors, upregulate the expression of DNMT3A/3B and develop mesodermal features that are characteristic of myofibroblasts.