Figure 3

Analysis of drug combinations on growth of breast cancer cells grown in 3D cultures. A. Cells were seeded on Matrigel in eight-well chamber slides as described in Materials and Methods. 3D cultures formed after two days and were treated every two to three days with single agents, vehicle (control), 1 nM paclitaxel (tax), 500 nM LY2109761 (LY), 10 μM CCT007093 (CCT), 25 nM mithramycin (mith) (upper panels) or a combination of drugs (lower panels). After 10 to 14 days, mammospheres were visualized using phase-contrast microscopy. Bar scale, 50 μm. B. To count cell numbers, the Matrigel was dissolved, mammospheres were collected, trypsinized and single cells were counted by trypan blue exclusion assay using a hemocytometer. The percent cell number relative to control was plotted for each drug or combination for the two cell lines. Error bars represent standard deviation from replicates from three independent experiments.