Signosis EL-016 is a CHO stable cell line expressing EGFR with the L858R mutation, resulting from c.2573T>G in exon 21. Produced using an MSCV-IRES-EGFP retroviral construct with GFP-based selection by FACS, it is validated by PCR and Western blot. This line aids research on tumor susceptibility and screening of EGFR TKIs such as gefitinib and erlotinib.