Review
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Oncol. Apr 10, 2016; 7(2): 189-199
Published online Apr 10, 2016. doi: 10.5306/wjco.v7.i2.189
Review of anticancer mechanisms of isoquercitin
Guilherme di Camillo Orfali, Ana Carolina Duarte, Vivien Bonadio, Natalia Peres Martinez, Maria Elisa Melo Branco de Araújo, Fernanda Bruschi Marinho Priviero, Patricia Oliveira Carvalho, Denise Gonçalves Priolli
Guilherme di Camillo Orfali, Ana Carolina Duarte, Vivien Bonadio, Scientific Initiation Program, Sao Francisco University Medical School, São Paulo 12916-900, Brazil
Natalia Peres Martinez, Maria Elisa Melo Branco de Araújo, Fernanda Bruschi Marinho Priviero, Patricia Oliveira Carvalho, Denise Gonçalves Priolli, Postgraduate Program in Health Science, Sao Francisco University Medical School, São Paulo 12916-900, Brazil
Author contributions: All authors performed research and final version of the manuscript.
Supported by São Paulo Research Foundation - FAPESP, No. 2012-04634-1.
Conflict-of-interest statement: Authors declare no conflict of interests for this article.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Denise Gonçalves Priolli, PhD, Postgraduate Program in Health Science, Sao Francisco University Medical School, Av São Francisco de Assis, 218 Jardim São José, Bragança Paulista, São Paulo 12916-900, Brazil. depriolli@terra.com.br
Telephone: +55-11-24548298 Fax: +55-11-24548000
Received: June 29, 2015
Peer-review started: July 14, 2015
First decision: September 17, 2015
Revised: October 19, 2015
Accepted: February 14, 2016
Article in press: February 16, 2016
Published online: April 10, 2016
Abstract

This review was based on a literature search of PubMed and Scielo databases using the keywords “quercetin, rutin, isoquercitrin, isoquercitin (IQ), quercetin-3-glucoside, bioavailability, flavonols and favonoids, and cancer” and combinations of all the words. We collected relevant scientific publications from 1990 to 2015 about the absorption, bioavailability, chemoprevention activity, and treatment effects as well as the underlying anticancer mechanisms of isoquercitin. Flavonoids are a group of polyphenolic compounds widely distributed throughout the plant kingdom. The subclass of flavonols receives special attention owing to their health benefits. The main components of this class are quercetin, rutin, and IQ, which is a flavonoid and although mostly found as a glycoside, is an aglycone (lacks a glycoside side chain). This compound presents similar therapeutic profiles to quercetin but with superior bioavailability, resulting in increased efficacy compared to the aglycone form. IQ has therapeutic applications owing to its wide range of pharmacological effects including antioxidant, antiproliferative, anti-inflammatory, anti-hypertensive, and anti-diabetic. The protective effects of IQ in cancer may be due to actions on lipid peroxidation. In addition, the antitumor effect of IQ and its underlying mechanism are related to interactions with Wnt signaling pathway, mixed-lineage protein kinase 3, mitogen-activated protein kinase, apoptotic pathways, as well proinflammatory protein signaling. This review contributed to clarifying the mechanisms of absorption, metabolism, and actions of IQ and isoquercitrin in cancer.

Keywords: Drug screening assays, Antitumor, Cancer, Flavonoids, Flavonols, Antioxidants, Neoplasms

Core tip: Flavonoids have gained a great deal of attention over the years, and their health benefits are the focus of the new research studies. This review contributed to clarifying the mechanisms of absorption and metabolism of isoquercitin, as well as emphasizing its chemopreventive and therapeutics effects in cancer. Overall, we presented a hypothesis of the underlying mechanisms of this biocompound in cancer.