TOPOISOMERASE II-DEPENDENT NOVEL ANTITUMOR COMPOUNDS MEROCIL AND MERODANTOIN INDUCE APOPTOSIS IN DAUDI CELLS

Three photoproducts of merocyanine 540 have been isolated, chemically characterized and synthesized. Two of these photoproducts, merocil and merodantoin, show significant antitumor activity in vitro and in vivo while demonstrating minimal toxicity to, normal cells and tissues. Tr eatment of lymphoma cells with these compounds resulted in a rapid dec line in macromolecular synthesis, DNA fragmentation inhibitable by act inomycin D and cycloheximide, and a marked rise in intracellular calci um. In vitro analysis revealed that activity of these compounds is dep endent on topoisomerase II. These results are discussed in terms of th e novel class of topoisomerase II-dependent compounds for potential us e in chemotherapy.