Docosahexaenoic acid (DHA), the main member of the omega-3 essential fatty acid family, is highly present in microalgae such as Phaeodactylum tricornutum. The general goal of our studies is to demonstrate the benefice of microalgae as food supplement for human health, including diabetes, obesity, dyslipidemia and cancer. Breast cancer is the most common women cancer in industrialized countries and environmental factors, such as differences in diet are likely to have an important influence on cancer emergence. Although widely studied, the effect of DHA on breast cancer development is unclear and the cellular mechanisms involved remain largely unknown. Our first study show that DHA incorporation in MDA-MB-231 breast cancer cell line has an anti-proliferative effect, induces apoptosis via a transient increase in caspase-3 activity and the promotion of nuclear  condensation, and reduces the invasive potential of MDAMB-231 cells.