Omega-3 free fatty acids inhibit tamoxifen-induced cell apoptosis

Fish oil, which contains omega-3 fatty acids mainly in the form of triglycerides, has benefits for reducing breast cancer risk, similar to tamoxifen action. However, it remains to be elucidated whether the combination of omega-3 free fatty acid (omega-3FFA) with tamoxifen leads to improved treatment in breast cancer. In this study, we observed that omega-3FFA induces MCF-7 cell apoptosis to suppress cell growth. The treatment of breast cancer cells with omega-3FFA attenuated tamoxifen-induced cell apoptosis. w-3FFA and tamoxifen significantly increased Erk1/2 and Ala phosphorylation levels in a dose and time dependent manner. Compared to omega-3FFA alone, the combination of tamoxifen with omega-3FFA significantly increased Erk1/2 and Akt phosphorylation levels. Because Erk1/2 and Akt activation has been linked to tamoxifen-related anti-estrogen resistance in breast cancer patients, these results indicate that omega-3FFA may interfere with the effects of tamoxifen in the prevention of breast cancer risk. (C) 2015 Elsevier Inc. All rights reserved.