Updates on resistance mechanisms of epidermal growth factor receptor tyrosine kinase inhibitors in non-small-cell lung cancer

Abstract

Efficacy of epidermal growth factor receptor tyrosine kinase inhibitors(EGFR-TKI)such as gefitinib and erlotinib is outstanding in the second or third-line treatment of some non-small cell lung cancer patients.However,disease in nearly all patients will aquire resistance to the drugs.Therefore,a better understanding of the mechanisms of resistance to EGFR kinase inhibitor is critical to further improve the efficacy of this class of agents.Genetic mutations of EGFR,cellular phenotypic changes,internalization of EGFR,the constitutive activation of downstream signal molecules or bypass signal pathway activation may provide tumor cells the ability of being independent of EGFR signaling and acquiring resistance tO EGFRTKI. Key words: Epidermal growth factor receptor tyrosin kinase inhibitors; Non-small cell lung cancer; Drug resistance; Signaling pathways