CU2-ANTHRAQUINONE COMPLEXES - FORMATION, INTERACTION WITH DNA, AND BIOLOGICAL-ACTIVITY()

Growth inhibition potency of the anthraquinones, anthraquinone-1,5-dis ulfonic acid and carminic acid, for Sarcoma 180 and L1210 leukemia cel ls in vivo and in vitro, was induced by the divalent transition metal ion, Cu2+. On the other hand spectroscopic titration data show that th e anthraquinone drugs form Cu'' chelate complexes (carminic acid: Cu2=1:6; anthraquinone-1,5-disulfonic acid: Cu2+=1:3). Furthermore the Cu 2+-drug complexes associate with DNA to form the Cu2+-anthraquinone-DN A ternary complexes. The formation of the complexes was further suppor ted by the H2O2-dependent DNA degradation, which can be inhibited by e thidium bromide, caused by the Cu2+-drug complexes. It is likely that the Cu2+-mediated cytotoxicity of the anthraquinone drugs is related w ith the Cu2+-mediated binding of the anthraquinone drugs to DNA and DN A degradation.