In the present study, we aimed to determine the biological function of lncRNA BC087858 and whether it could induce acquired resistance to EGFR-TKIs by activating PI3K/AKT/ERK pathway and epithelial-mesenchymal transition (EMT) in EGFR-mutant NSCLC. The gene discussed is PIK3CA; the disease is non-small cell lung carcinoma.