Signosis EL-007 is an HCC827 stable cell line transfected with an empty vector, serving as a control for EGFR-expressing HCC827 lines. It supports studies on tumor susceptibility and screening of EGFR TKIs like gefitinib and erlotinib. The cell line was generated using an MSCV-IRES-EGFP retroviral construct with GFP-based selection by FACS and validated by PCR and Western blot.