EGFR and non-small cell lung carcinoma: PI3K/AKT is a key downstream signalling pathway of EGFR and abnormal activation of the PI3K/AKT signalling pathway is one of the most relevant mechanisms of acquired targeted therapies resistance in EGFR‐mutated NSCLC patients.32, 33 Our results demonstrated that EGFR‐TKI–resistant cell H1975–derived exosomes can induce gefitinib resistance in sensitive cell PC9 through activating PI3K/AKT signalling pathway.