Toxicity of fatty acids on murine and human melanoma cell lines.

High concentrations of certain fatty acids can cause cell death via apoptosis or necrosis. The aim of this study was to investigate the toxicity of saturated and unsaturated fatty acids on melanoma cell lines, which was evaluated by either loss of membrane integrity and/or DNA fragmentation using flow cytometric analysis. Evidence is presented that saturated and unsaturated fatty acids exert toxic effects on melanoma cells through loss of membrane integrity and/or DNA fragmentation. Arachidonic and linoleic acids were the most effective in decreasing the number of viable S91 murine melanoma cells, causing loss of membrane integrity and DNA fragmentation at 100 microM concentration already after 24 h in culture. In B16F10 murine melanoma cells, palmitic acid was the most toxic, inducing cell death by both apoptosis and necrosis. The human melanoma cell lines were more resistant to the toxic effect of fatty acids. In SK-Mel 23 cells, indications of cytotoxicity were detected only after 48 h treatment with arachidonic, linoleic, palmitic and palmitoleic acids at 200 microM concentration. Linoleic acid was the most toxic for this cell line. In SK-Mel 28 human cells, only palmitic acid caused a significant decrease of the number of viable cells, inducing DNA fragmentation after 24 and 48 h treatments at 200 microM concentration.