Membrane fatty acids of breast carcinoma: Contribution of host fatty acids and tumor properties

To assess the part that host fatty‐acid supply and tumor‐specific fatty‐acid utilization contribute to the membrane lipid composition of tumor tissue, intra‐individual comparisons of membrane fatty acids were carried out between breast‐carcinoma tissue and non‐tumorous breast tissue adjacent to the tumor and taken as reference. Phospholipids were purified by thin‐layer chromatography from tumor biopsies obtained from 59 patients with a localized presentation of breast cancer, and fatty acids analyzed by capillary gas chromatography. Elevated levels of palmitic, palmitoleic and arachidonic acids, along with a low level of linoleic acid, were observed in membrane phospholipids of tumors with poor histoprognostic grade. The level of mono‐unsaturated fatty acids was higher, and the level of essential fatty acids was lower in the tumor than in the reference breast tissue. Fatty‐acid‐desaturating activity was not detectable in tumors. A positive relationship was observed among patients for most of the fatty acids between carcinoma and non‐tumorous breast tissue, except for mono‐unsaturated and essential fatty‐acid levels, which were not correlated between both tissues. These data suggest that mechanisms specifically related to malignant transformation and tumor progression influence the membrane fatty‐acid profile of breast carcinoma. Fatty acid supply to the tumor, possibly modified by metabolic conditions related to the host, also seems to play a decisive role in this composition.