Fig. 6

Inhibition of lipid rafts suppresses the formation of the ER-c-Src-HER2 complex and partially restores tamoxifen sensitivity. a BT474 cells were treated with vehicle (Con) or nystatin (N) (5 μg/ml) for 2 h and subjected to immunoprecipitation and immunoblotting analysis as indicated. b Cells were seeded in 6-well plates (2.5 × 10⁴ cells/well) for 24 h and then treated with vehicle or nystatin(5 μg/ml) for 2 h, followed by treatment with vehicle, E2(10 nmol/L), TAM(1 μmol/L), or the combination for 4 h. c Cells were seeded in 96-well plates (5000 cells/well). At 24 h after plating, cells were treated with vehicle or nystatin (5 μg/ml) for 2 h, and then treated with vehicle, E2(10 nmol/L), TAM(1 μmol/L), or the combination. After 48 h, MTT assays were performed. The bar graph shows the sensitivity of BT474 cells to tamoxifen before and after treatment with nystatin. Data represent the mean ± SD of at least three independent experiments. P values were determined by the Student’s t test. (*p < 0.05) d BT474 cells were treated with nystatin (5 μg/ml) for 2 h, and then treated with E2 (10 nmol/L) and/or TAM (1 μmol/L). Cells were plated in triplicate. On day 14, images were captured and the number of colonies was determined. Data represent the mean ± SD of at least three independent experiments. P values were determined by the Student’s t test. (*p < 0.05)