Figure 1.
BT-474 and SK-BR-3 cells are sensitive to lapatinib. A, BT-474 and SK-BR-3 cells were treated with 0 (vehicle), 0.1, or 1 μmol/L lapatinib for 24 h. Western blot analysis was done to detect phosphorylated EGFR (Y1173), HER2 (Y1248), Akt (S473), extracellular signal-regulated kinase1/2 (p-ERK; T202/Y204), and p27. β-actin was used as a loading control. B, BT-474 and SK-BR-3 cells were plated in 96-well plates and treated with 10-fold serial dilutions of lapatinib ranging from 0.001 to 1 μmol/L for 72 h. The percentage cell viability was evaluated by WST-1 assay. Each experiment was repeated thrice independently.