Figure 2. Apigenin inhibits anchorage-dependent and anchorage-independent clonogenic survival of BT-474 cells.

(A) BT-474 cells were seeded into six-well culture plates at a density of 5×10² cells/well. After overnight incubation, cells were treated with different concentrations of apigenin (0–60 μM) and maintained for 10 days at 37°C. Finally, plates were stained with haematoxylin and the colony number was counted. (B) 1×10³ cells were suspended in 1 ml of 0.6% soft agar that was layered on top of 1 ml of 1% solidified agar in each well of 12-well plates. The plates were then incubated for 15–21 days in complete RPMI medium containing apigenin. Colonies were stained with crystal violet.