HU-331

HU-331 is a quinone anticarcinogenic drug synthesized from cannabidiol, a cannabinoid in the Cannabis sativa plant. It showed a great efficacy against oncogenic human cells. HU-331 does not cause arrest in cell cycle, cell apoptosis or caspase activation. HU-331 inhibits DNA topoisomerase II even at nanomolar concentrations, but has shown a negligible effect on the action of DNA topoisomerase I. The cannabinoid quinone HU-331 is a very specific inhibitor of topoisomerase II, compared with most known anticancer quinones. One of the main objectives of these studies is the development of a new quinone derived compound that produces anti-neoplastic activity while maintaining low toxicity at therapeutic doses.

== Mechanism of action == Inhibitors of topoisomerases can act at two different levels. First inhibiting topoisomerase, which stabilize the topoisomerase-DNA complex and thus introduce DNA breaks in the wires that lead to apoptosis, then inhibiting the catalytic activity of topoisomerase, which hinders the activity of these enzymes without introducing breaks into the DNA chains. HU-331 seems to be a catalytic inhibitor of topoisomerase II, probably by enzymatic ligation to the protein. This molecule does not cause damage to DNA, but protects cells from damage, natural, or induced by other inhibitors of topoisomerase II that act as inhibitors of topoisomerase. Even when 60% of the target cells are killed by treatment with HU-331, other cells' nucleic content remains unharmed, with less breakage of DNA chains that control important cellular functions.