Potential anti-tumor effects of Mugil cephalus processed roe extracts on colon cancer cells

The salted-semidried mullet ovary product, bottarga, is a Mediterranean food rich in n-3 PUFA EPA and DHA. We studied and compared the effects on cell viability, sensitivity to the anti-tumor drug 5-fluorouracil, and lipid composition, in colon cancer Caco-2 cells after 24 h incubation with oils and hydrophilic extracts obtained from two bottarga samples stored at different conditions. The cellular absorption of bottarga lipids was assessed in cancer cells by the evaluation of lipid accumulation in cytoplasmic lipid droplets by fluorescence microscopy. Bottarga oil showed a significant in vitro inhibitory effect on the growth of cancer Caco-2 cells and the ability to potentiate, at non-toxic concentration, the growth inhibitory effect of 5-fluorouracil. Moreover, bottarga oil induced in cancer Caco-2 cells marked changes in fatty acid composition, with a significant accumulation of the n-3 PUFA EPA and DHA, and cytoplasmic lipid droplet formation. Also bottarga hydrophilic extract, characterized by means of ¹H NMR spectroscopy, exhibited a reduction in cancer cell viability, without affecting cell lipid profile. Cell cholesterol levels were unmodified by all treatments. The results showed interesting anti-tumor properties of bottarga lipids, and qualify this fish product as a food with nutraceutical properties and potential benefits in colon cancer prevention.