Mechanisms and new strategies on drug resistance of EGFR-mutant non-small cell lung cancer

Epidermal growth factor receptor(EGFR)-mutant non-small cell lung cancer(NSCLC) has been defined as a distinct subset of lung cancer in the clinic.Although EGFR-mutant tumours most often display more sensitivity to tyrosine kinase inhibitor(TKI),clinical resistance to them remains a major problem.Based on the different molecular mechanisms of primary and acquired resistance,multiple clinical trials of the second or third-generation EGFR TKI and drug combinations with inhibitors targeting to EGFR downstream protein have been initiated and are being planned.This review summarizes recent progress in mechanisms and new overcoming strategies on better treatment of drug resistant cancer cells in EGFR-mutant NSCLC.