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.