The results of western blotting, immunofluorescence staining, and the APO-BrdU TUNEL assay demonstrated that SIRT1 K/D in combination with erlotinib increased PARP and caspase-3 cleavage (Fig. 6F–H; Supplementary Fig. 19c–e), indicating that the combination of SIRT1 K/D with chemotherapy drugs or erlotinib could sensitize KrasMut lung cancer cells to overcome chemoresistance. The gene discussed is CASP3; the disease is lung cancer.