EGFR and non-small cell lung carcinoma: In NSCLC cell lines with different EGFR-TKI resistance mechanism, while gefitinib in combination with vorinostat resulted in significantly decreased cell viability and increased apoptosis, we noted that adding vorinostat could up-regulate the pro-apoptotic proteins BIM and BAX in PC-9GR and H1650-M3 cells but not in H1975 cells, the therapeutic strategy could down-regulate the anti-apoptotic protein Bcl-xL in H1975 cells but not in PC-9GR and H1650-M3 cells.