Anti-proliferative effects and phenotypic alterations induced by 8-hydroxyquinoline in melanoma cell lines

The effect of the transition metal chelator, 8-hydroxyquinoline (8-HQ), was examined on the growth and phenotype expression of B16 mouse melanoma cells. Micromolar concentrations of 8-HQ inhibited the growth of B16 cells as well as human melanoma cell lines. Removal of 8-HQ from the culture medium restored normal cell growth. Growth inhibition by 8-HQ was accompanied by phenotypic alterations that included changes in cell morphology, increased production of melanin and enhanced activities of the enzymes gamma-glutamyl transpeptidase and NADPH cytochrome c reductase. These changes might be associated with a better differentiated phenotype.