Fusarochromanone is a toxic metabolite produced by Fusarium equiseti, a fungus present in decaying cereal plants in northern latitudes; it has been detected in various food grains.
Fusarochromanone has been shown to have both stimulatory and inhibitory effects on various mammalian cells, depending on the concentration used. Whether these cytotoxic effects can be used in the clinical treatment of
tumors remains to be established. Here, we evaluated the effects of
fusarochromanone on the growth of human
melanoma cells both in vitro and in vivo. In vitro, low concentrations (0.1-1 nmol/l) of
fusarochromanone were found to be cytotoxic to many
melanoma cell lines. In contrast, growth of normal melanocytes was inhibited only at much higher
fusarochromanone concentrations (100-200 nmol/l). In vivo, the growth of
melanoma cells implanted subcutaneously in immuno-compromised mice was significantly (P<0.05) reduced by daily administration of
fusarochromanone. Immunohistological analyses indicated a significant (P<0.05) increase in the expression of active
caspase-3 in
tumor masses of mice treated with
fusarochromanone, compared with controls. Together, these observations show that
fusarochromanone increased apoptosis of
tumor cells and reduced
tumor growth in vivo. Therefore, the effects of
fusarochromanone warrant further investigation as an adjuvant molecule to prevent growth and recurrence of
melanomas.