EGFR TKI-resistant NSCLC cell lines were generated as previously described by dose escalation exposure of TKI-sensitive NCI-H1975 (EGFRL858R/T790M) NSCLC cells to ASK120067 or osimertinib (denoted by 67R and AZDR, respectively).3 We further validated the decreased sensitivity of resistant cells to the respective EGFR TKI compared to parental cells using colony formation and cell proliferation assays (Supplementary Fig. 1a, b). The gene discussed is EGFR; the disease is non-small cell lung carcinoma.