Figure 2.

Melatonin attenuates MDA-MB-231 cell migration. MCF10A and MDA-MB-231 cells were treated for 48, 72, or 168 h with melatonin (10–1000 nM) or the vehicle (control) and were subjected to wound healing assay as described in Experimental procedures. A, representative images were acquired at 0, 24, and 48 h from the beginning of the assay. Bars represent 200 μm. The dotted lines define the areas lacking cells. B and C, quantification of the wound size, in micrometers, at the different conditions, expressed as the mean ± SD of four independent experiments. Analysis of statistical significance was performed using two-way ANOVA (for B: 0 h, F values were 0.21, 0.02, and 0.58 and p values were 0.88, 0.97, and 0.73 for concentration, time, and the interaction respectively; for B: 24 h, F values were 1.11, 0.60, and 1.14 and p values were 0.34, 0.54, and 0.33; for B: 48 h, F values were 1.72, 0.86, and 0.62 and p values were 0.16, 0.42, and 0.71; for C: 0 h, F values were 0.35, 0.31, and 0.17 and p values were 0.78, 0.72, and 0.98; for C: 24 h, F values were 1570, 616.6, and 447.6 and p values were <0.0001 in all cases; for C: 48 h, F values were 6019, 958.4, and 608.1 and p values were <0.0001 in all cases) with post-hoc Tukey test (∗p < 0.0001 compared with the scratch time = 0 h. ^$p < 0.01 compared with the corresponding time in vehicle-treated cells).