A Cla response of Human Breast cancer cells: mechanisms involved

Conjugated linoleic acid (CLA) has beneficial effects against breast carcinogenesis. In its antiproliferative action we hypothesized a cross-talk between PPARbeta and E-cadherin/ß-catenin systems, important in cellular adhesion and signal transduction. ß-catenin system is regulated by ERK and PI3K/Akt cascades, crucial in growth signal transmission. We tested CLA interference with these pathways in ERα+ (MCF-7) and ERα- (MDA-MB-231) breast cancer cells. We used immunoblotting, immunofluorescence, immunoprecipitation, zymography, Boyden chamber techniques. CLA is more effective in MCF-7 cells: it transactivates PPARbeta and induces E-cadherin/ß-catenin complex formation at plasmamembrane. In MDA-MB-231 cells upregulates PPARα and induces apoptosis. In both cell lines inhibits ERK and PI3K/Akt signalling and reduces cell invasiveness. CLA action involves signalling pathways recently considered as new targets for anti-cancer strategies.