Resveratrol and Its Analogs as Antitumoral Agents for Breast Cancer Treatment

Resveratrol (3,5,4'-tri-hydroxystilbene) (RSV), a naturally occurring phytoalexin, readily available in the diet, has gained interest as a non-toxic agent capable of displaying cancer-preventing and anti-cancer properties. Several studies, using both in vitro and in vivo models, have illustrated RSV capacity to modulate a multitude of signaling pathways associated with cellular growth and division, apoptosis, angiogenesis, invasion and metastasis. However, its clinical application is limited because of a low oral bioavailability with high adsorption but rapid metabolism and low tissue concentrations. Several chemical modifications to the backbone structure have been made for the purpose of improving pharmacokinetic parameters. One promising strategy involves the introduction of methoxylic or hydroxylic groups on the phenylic rings of RSV. Moreover, by replacing the alkene linker between the two aromatic rings with a heterocyclic system rigid analogs such as 2,3-thiazolidin-4-ones and 3-chloro-azetidin-2-ones that displayed higher cytotoxic activity and hence higher ability to inhibit in vitro breast cancer cell growth have been synthesized. In vitro studies have demonstrated, for some of these compounds, a greater bioaccessibility than RSV and more selective inhibitory effects on breast cancer cell growth. Further investigations, particularly in vivo, are required as next step to implicate these analogs as pharmacologic agents for a possible clinical anticancer application.