Osimertinib(OSI),also known as AZD9291,is a third-generation epidermal growth factor receptor tyrosine kinase inhibitor that has been approved for the treatment of non-small cell lung cancer(NSCLC)patients harboring EGFR T790M mutation.Herein,we indicated for the first time that OSI increased the accumulations of cytoplasmic vacuoles,the expression of phosphatidylethanolamine-modified microtubule-associated protein light-chain 3(LC3-Ⅱ),and the formation of GFP-LC3 puncta in various cancer cells.