A Review of Quercetin: Anti-Cancer Activity

Abstract

Quercetin is the principal flavonoid compound commonly extracted from cranberries, blueberries, apples and onions. It possesses a wide spectrum of bio-pharmacological properties and may offer promising new options for the development of more effective chemo-preventive and chemo-therapeutic strategies owing to its powerful antioxidant and free-radical scavenging properties. Several studies demonstrated that quercetin has a significant role in inhibition of tumor and cancer cells on breast, colon, prostate, ovary, endometrium, and lung. Quercetin treatment has been associated with selective anti-proliferative effects and induction of cell death, probably through an apoptotic mechanism, in breast or other cancer cell lines but not in normal cells. Quercetin is universally known for its low toxicity as a natural product despite the limited information on dosing regimens. The major problem associated with the use of quercetin, is the very low bioavailability. Beside cancer chemotherapy, it also exhibits various pharmacological actions including: antiviral, antioxidant, anticancer, antimicrobial, anti-inflammatory, neurological effects, cardiovascular, and hepatoprotective. Quercetin has been reported as a potent anticancer agent during in vitro studies on various cancer cell lines and in vivo studies on rodents especially mice. Quercetin has radical scavenging potential, therefore, it is capable of preventing cancer induced by oxidative stress. The chemo-protective action of quercetin through apoptosis and metastasis against tumor cell lines makes it a strong candidate as a potential anticancer agent.