To establish lorlatinib resistant cells in vitro, ALK-TKI-sensitive patient-derived JFCR-028-3 parental cells obtained from the pleural effusion of a patient with EML4-ALK-positive NSCLC before alectinib treatment were exposed to high concentrations of lorlatinib (1 or 3 μM) for 1 week. The gene discussed is EML4; the disease is non-small cell lung carcinoma.