PHOSPHOLIPID AND TRIACYLGLYCEROL FATTY ACIDS IN BLOOD AND BREAST TISSUE OBTAINED FROM WOMEN AT INCREASED RISK OF BREAST CANCER

Abstract

The purpose of this study was to determine the fatty acids composition in breast tissue of women with increased risk of breast cancer, and if the fatty acid composition in both PL and TAG in blood, both plasma and RBC, correlated to the fatty acid composition in breast tissue in the same population. Fifty subjects from clinical patients in a study to develop an assessment of breast cancer risk based on epidemiologic and biologic risk variables enrolled in current study. Blood and tissue samples were taken and dietary history questionnaire, which including usual supplement intake were distributed when the subject were enrolled. The blood and breast tissue samples were analyzed by gas-liquid chromatography and calculated by the weighed percentage of total areas compared with Supelco 37 mixture as a standard. The means of total n-3 PUFA of PL in plasma and RBCs for the subjects were 4.00 ± 1.09% and 5.47 ± 1.50%, respectively, and in plasma TAG the mean was 2.21 ± 1.34%. The means of total n-3 PUFA of PL and TAG in breast tissue were 0.36 ± 0.27% and 1.28 ± 0.44%, respectively. The means of total n-6 PUFA of PL in plasma and RBCs for the subjects were 34.04 ± 3.22% and 28.10 ± 3.45%, respectively, and in plasma TAG was 28.35 ± 3.97%. The means of total n-6 PUFA of PL and TAG in breast tissue were 2.75 ± 0.99% and 17.53 ± 2.78%. A statistically significant correlation was found in the ratio of total and long chain n-3 (n-3 LCPUFA) to total n-6 PUFA in PL in blood and breast tissue, r=0.801 and 0.653 for total n-3 PUFA in RBC and plasma (p<0.01), and r=0.631 and 0.524 for n-3 LCPUFA in RBC and plasma (p<0.01), but no relationship between breast and blood fatty acids in TAG in individual or combined n-3 and n-6 PUFA was found between breast tissue and blood. The ratio of long chain n-3 PUFA to total n-6 PUFA in phospholipid in blood represents the same ratio in breast tissue and could be used as a marker of breast phospholipid n-3 to n-6 ratio though relative amount of n-3 and n-6 fatty acids are very different between red blood cells and breast phospholipids. The only link found previously between fatty acids in breast tissue and breast cancer is related to the n-3 to n-6 fatty acid ratio in TAG. We need to continue to study their relationships in women who take a supplement of n-3 LCPUFA.