xanthohumol and myricetin

Colorectal cancer (CRC) is the second most fatal and the third most diagnosed type of cancer worldwide. Despite having multifactorial causes, most CRC cases are mainly determined by dietary factors. In recent years, a large number of studies have attributed a protective effect to polyphenols and foods containing these compounds (fruits and vegetables) against CRC. Indeed, polyphenols have been reported to interfere with cancer initiation, promotion, and progression, acting as chemopreventive agents. The aim of this review is to summarize the main chemopreventive properties of some polyphenols (quercetin, rutin, myricetin, chrysin, epigallocatechin-3-gallate, epicatechin, catechin, resveratrol, and xanthohumol) against CRC, observed in cell culture models. From the data reviewed in this article, it can be concluded that these compounds inhibit cell growth, by inducing cell cycle arrest and/or apoptosis; inhibit proliferation, angiogenesis, and/or metastasis; and exhibit anti-inflammatory and/or antioxidant effects. In turn, these effects involve multiple molecular and biochemical mechanisms of action, which are still not completely characterized. Thus, caution is mandatory when attempting to extrapolate the observations obtained in CRC cell line studies to humans.

Topics: Animals; Anti-Inflammatory Agents; Anticarcinogenic Agents; Antioxidants; Apoptosis; Catechin; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Diet; Flavonoids; Fruit; Humans; Phenols; Polyphenols; Propiophenones; Quercetin; Resveratrol; Rutin; Stilbenes; Vegetables

Our aim was to investigate the effect of several dietary polyphenols on uptake of (14)C-butyrate ((14)C-BT) by Caco-2 cells and try to correlate this effect with the modulation of the anticarcinogenic effect of BT in these cells. Acutely, uptake of (14)C-BT (10 μM) was decreased by resveratrol, quercetin, myricetin, and chrysin, and increased by xanthohumol, catechin, and epicatechin; and uptake of (14)C-BT (20 mM) was reduced by resveratrol, quercetin, myricetin, chrysin, EGCG, and epicatechin. Resveratrol acts as a competitive inhibitor of (14)C-BT uptake. Chronically, quercetin and EGCG increased uptake of (14)C-BT (10 μM), whereas myricetin, rutin, chrysin, and xanthohumol decreased it. Moreover, catechin (1 μM), quercetin, myricetin, rutin, EGCG, and chrysin increased uptake of (14)C-BT (20 mM), whereas catechin (0.1 μM) decreased it. EGCG, myricetin, and catechin decreased MCT1 mRNA expression, while chrysin increased it; quercetin, rutin, and xanthohumol had no effect. BT (5 mM; 48 h) markedly decreased cellular viability and proliferation and increased cell differentiation and apoptosis. In general, combination of polyphenolic compounds with BT did not significantly modify these changes. In conclusion, changes in uptake of BT induced by polyphenols do not correlate with changes on the effect of BT upon cell viability, cell proliferation, differentiation, and apoptosis.

Topics: Analysis of Variance; Anticarcinogenic Agents; Apoptosis; Butyrates; Caco-2 Cells; Catechin; Cell Differentiation; Cell Proliferation; Cell Survival; Flavonoids; Humans; Phenols; Polyphenols; Propiophenones; Quercetin; Regression Analysis; Resveratrol; Rutin; Stilbenes