Inhibition of Invasion by Polyphenols from Citrus Fruit and Berries in Human Malignant Glioma Cells In Vitro.

BACKGROUND/AIM The outlook for patients with high grade glioma (HGG) remains dismal. Hence, attention has focused on numerous innovative treatments. Our group has proposed a strategy on the use of a combination of polyphenols, as anti-invasive agents for the management of these neoplasms. MATERIALS AND METHODS The aim of this study was to evaluate the in vitro effects of citrus flavonoids (tangeretin, nobiletin, naringin and limonin) and berry extracts (chokeberry, elderberry and bilberry) on selected mediators of invasion in 2 HGG cell cultures. RESULTS The IC50 values could only be determined for tangeretin and chokeberry extract. The rest were non-functional in this context. Immunocytochemistry and flow cytometry results showed that chokeberry extract was most effective in down-regulating the expression of CD44. Similarly, RT-PCR data supported its ability to reduce gene expression of MMP-14 and EGFR. 2D invasion assays confirmed that inhibition is greater with chokeberry extract. CONCLUSION Both polyphenols have anti-invasive potential but chokeberry extract is a stronger agent for glioma management.