Flavonoids as Anticancer Agents: Recent Progress and State of the Art?

The cancer preventing effect of flavonoids is largely documented in literature. In addition to their nutritional value as cancer preventing agents, they have been studied as drug candidates in cancer treatment. Many mechanisms of action have been identified, including carcinogen inactivation, antiproliferation, cell cycle arrest, induction of apoptosis and differentiation, inhibition of angiogenesis, antioxidative activity and reversal of multidrug resistance. The diversity in the biological targets of flavonoids has led during the last twenty years to an extensive research toward medicinal chemistry of flavonoids with the aim to obtain anticancer drugs. Some anticancer agents derived from flavonoids are emerging as major anticancer drugs or chemosensitizers. This review will shed light on recent molecules obtained from efforts made on medicinal chemistry of flavonoids. A special focus will be made on flavonoid derivatives being studied in clinical trials. Keywords: Anticancer potential, Clinical trials, Drug candidates, Flavonoids, Structural analog, radical-scavenging, ion-chelating abilities, reactive oxygen species (ROS), cytochrome P450, apoptosis, antiproliferation, angiogenic processes, structure-activity relationship (SAR), adenine moeity, isoflavones