In conclusion, we demonstrate for the first time that IGF1R/NF-κB pathway is involved in the acquisition of both EMT phenotype and EGFR TKI resistance in gefitinib-resistant EGFR-mutant NSCLC, suggesting that IGF1R/NF-κB pathway could be a novel therapeutic target for advanced NSCLC patients. Here, NFKB1 is linked to non-small cell lung carcinoma.