Flavonoids as Potential Anticancer Agents in Clinics: Where Have We Reached So Far?

Abstract

The large number of plant-derived molecules have been explored in cancer cell lines and preclinical studies. As an outcome of these studies, decent number of isolated compounds expressed their candidature for being explored in clinical trials. The thrust behind development of plant-derived molecules is their low-cost and lesser side effects as compared to synthetic anticancer agents. Flavonoids are synthesized by plants as secondary metabolites and are a diverse chemical class possessing a wide spectrum of pharmacological activities such as anti-inflammatory, antiplatelet, antidiabetic, antimicrobial, cardioprotective, as well as anticancer activities. Various flavonoids especially genistein, myricetin, quercetin, luteolin, hesperidin, and epigallocatechin-3-gallate have been widely studied in cancer cell lines and animal models of tumorigenesis. In the recent past, the phase 1 and 2 clinical trials conducted with the aforementioned molecules have revealed promising results. Moreover, their supplementation reduced radiotherapy and chemotherapeutic agent-induced side effects in cancer patients. The present book chapter summarizes the subclasses of flavonoids with special reference to selected molecules from each class, which exhibited anticancer activity in cell lines and at present are being explored in various clinical trials.