Figure 1.

Melittin inhibits MCF-7 cell invasion. MCF-7 cells were plated onto the upper chamber. The cells were incubated for 1 h for adherence and then treated with either Dulbecco's modified Eagle's medium (basal) or varying concentrations of melittin (0.5–2.5 µg/ml) in the upper chamber for 24 h. The invasion was measured by Transwell assay. Scale bar, 50 µm. (A) Images of cells were captured using an inverted microscope subsequent to staining by crystal violet: (a) 0, (b) 0.5, (c) 1.5 and (d) 2.5 µg/ml. (B) The absorbance was determined using a microplate reader at 570 nm, subsequent to destaining with 33% acetic acid (*P<0.01 vs. 0; n=5). OD, optical density.