Fig. 1. Representative AFM images of MCF-7/S and MCF-7/ADR cells. The first column (A1 and B1) and third column (A3 and B3) show height and three dimensional images of the entire MCF-7/S and MCF-7/ADR cells, respectively. The second column (A2, a2, B2 and b2) are peak force error images to highlight the fine features in the images. The first column (a1 and b1) and third column (a3 and b3) are the high-resolution zoomed height and three dimensional images (10 × 10 μm²) of the cells, respectively. The colors in the images indicate different heights with light and dark colors corresponding to higher and lower topography, respectively.