EGFR and colorectal cancer: To determine the effects of gefitinib (GEF) and salinomycin (SAL) in combination on human colorectal cancer cell viability, SW1116, LOVO, HCT-116, SW480 and HT-29 cells with different EGFR status were exposed to increasing concentrations of GEF and SAL as single agent for 48 h respectively, and effects on cell viability were assessed by CCK8 assay.