Betalains increase vitexin-2-O-xyloside cytotoxicity in CaCo-2 cancer cells

- Vitexin-2-O-xyloside was purified from Beta vulgaris cicla seeds.
- Betalains were purified from red beet root by anionic exchange chromatography.
- Betalains increase vitexin-2-O-xyloside cytotoxicity in CaCo-2 colon cancer cells.
- The cytotoxic effect is mediated by activation of an intrinsic apoptotic pathway.

Vitexin-2-O-xyloside (XVX) from Beta vulgaris var. cicla L. (BVc) seeds, betaxanthin (R1) and betacyanin (R2) fractions from Beta vulgaris var. rubra L. (BVr) roots were combined and tested for cytotoxicity in CaCo-2 colon cancer cells. XVX was the most cytotoxic molecule, but the combination of XVX with R1 and R2 significantly prolonged its cytotoxicity. Cytotoxicity was mediated by the intrinsic apoptotic pathway, as shown by an increase in Bcl2-like protein 4, cleaved Poly ADP-Ribosyl Polymerase 1 and cleaved Caspase 3 levels with a parallel decrease in anti-apoptotic protein B-cell leukemia/lymphoma 2 levels. R1 and R2, used alone or in combination, reduced oxidative stress triggered by H2O2 in CaCo-2 cells. Betalains dampened cyclooxygenase-2 and interleukin-8 mRNA expression after lipopolysaccharide induction in CaCo-2, showing an anti-inflammatory action. Our results support the use of a cocktail of R1, R2 and XVX as a chemopreventive tool against colon cancer.