Farnesyl-O-acetylhydroquinone and geranyl-O-acetylhydroquinone suppress the proliferation of murine B16 melanoma cells, human prostate and colon adenocarcinoma cells, human lung carcinoma cells, and human leukemia cells

Farnesyl-O-acetylhydroquinone (IC50=2.5 μmol/l) suppressed the proliferation of murine B16F10 melanoma cells with a potency much greater than those of farnesol (IC50=45 μmol/l) and farnesyl anthranilate (IC50=46 μmol/l), its alcohol, and ester counterparts with proven anti-tumor activities in vivo. Geranyl-O-acetylhydroquinone (IC50=5.1 μmol/l) also had a much-improved activity compared to geraniol (IC50=160 μmol/l) and geranyl anthranilate (IC50=30 μmol/l). The suppression by farnesyl-O-acetylhydroquinone was concentration- and time-dependent and was accompanied by arrest of cell cycle at G1 and G2/M phases as shown by flow cytometry. Farnesyl-O-acetylhydroquinone and lovastatin had additive impact on B16 cell proliferation. Farnesyl-O-acetylhydroquinone also suppressed the proliferations of human cancer cells HL-60, DU145, PC-3, LNCaP, Caco-2, and A549. Our results suggested that farnesyl derivatives, suppressors of tumor 3-hydroxy-3-methylglutaryl coenzyme A reductase activities, have potential as chemopreventive or chemotherapeutic agents.