The effect of resveratrol compounds (1-4) on proliferation of melanoma cells and melanocytes. Metastatic F10 cells, non-metastatic F1 cells (each plated at 3×103 cells per well), or melanocytes (9×103 cells per well) were treated for 40 h with 10 μM of the indicated analogue or an equivalent volume of ethanol (0.1%, v/v). The fluorescent signal was read after a 3-h treatment with Alamar Blue (5%, v/v). For each condition, six replicate measurements were averaged and reported as the percentage ± s.d. of the value for control-treated cells (*, P < 0.0001). The results are representative of two or more independent experiments.