To validate the activation of IGF1R/NF-κB p65 signaling in gefitinib-resistant mouse lung adenocarcinoma, we used genetically engineered mice harboring a doxycycline-inducible human EGFR exon 19 deletion transgene (hEGFR Del19) [51]. This evidence concerns the gene NFKB1 and lung adenocarcinoma.