Quercetin in Cancer Treatment, Alone or in Combination with Conventional Therapeutics?

Abstract

Abstract:Cancer is a problem of global importance, since the incidence is increasing worldwide and therapeutic options are generally limited. Thus, it becomes imperative to find new therapeutic targets as well as new molecules with therapeutic potential for tumors. Flavonoids are polyphenolic compounds that may be potential therapeutic agents. Several studies have shown that these compounds have a higher anticancer potential. Among the flavonoids in the human diet, quercetin is one of the most important. In the last decades, several anticancer properties of quercetin have been described, such as cell signaling, pro-apoptotic, anti-proliferative and anti-oxidant effects, growth suppression. In fact, it is now well known that quercetin has diverse biological effects, inhibiting multiple enzymes involved in cell proliferation, as well as, in signal transduction pathways. On the other hand, there are also studies reporting potential synergistic effects when combined quercetin with chemotherapeutic agents or radiotherapy. In fact, several studies which aim to explore the anticancer potential of these combined treatments have already been published, the majority with promising results. Actually it is well known that quercetin can act on the chemosensitization and radiosensitization but also as chemoprotective and radioprotective, protecting normal cells of the side effects that results from chemotherapy and radiotherapy, which obviously provides notable advantages in their use in anticancer treatment. Thus, all these data indicate that quercetin may have a key role in anticancer treatment. In this context, this review is focused on the relationship between flavonoids and cancer, with special emphasis on the role of quercetin.

Enhancing the anti-ovarian cancer activity of quercetin using a self-assembling micelle and thermosensitive hydrogel drug delivery system

“…The latest research demonstrates that quercetin has a variety of pharmacological activities and its anti-cancer activity can induce tumor cell apoptosis, regulate tumor cell proliferation and tumor angiogenesis, and inhibit the signal pathways of many important targets. [15][16][17][18][19][20][21][22][23][24] All the advantages make quercetin nature's nominee for a cancer cure. However, quercetin's low water solubility is a fatal weakness that limits its effectiveness in clinical application signicantly.…”

Potential of the Flavonoid Quercetin to Prevent and Treat Cancer – Current Status of Research

“…Perorální a lokální aplikace quercetinu v klinické studii na 64 pa cientech dokázala zmírnit poškození kůže při radioterapii v lokalitě karcinomů hlavy a krku [61]. Vedle toho studie ukazují na schopnost potenciace účinku onkologické léčby při kombinaci quercetinu s chemoterapií a radioterapií a podporují další výzkum v této oblasti [62]. Synergizmus byl prokázán u mnoha druhů chemoterapeutik [63].…”

Resveratrol (3,5,4′-trihydroxystilbene) and its properties in oral diseases

“…RSV is comprised of a number of polypheinolic compounds, including curcumin (111), rottlerin (112), genistein (113) and quercetin (114,115). RSV has been purported to be of potential use in cancer treatment and evidence indicates that it may inhibit pathways contributing to cell proliferation (116).…”