Premium
Comparison of linoleic acid and eicosapentaenoic acid incorporation into human breast cancer cells
Author(s) -
Hatala Mary Ann,
Rayburn Jodie,
Rose David P.
Publication year - 1994
Publication title -
lipids
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.601
H-Index - 120
eISSN - 1558-9307
pISSN - 0024-4201
DOI - 10.1007/bf02536250
Subject(s) - lipidology , eicosapentaenoic acid , clinical chemistry , linoleic acid , docosahexaenoic acid , breast cancer , chemistry , biochemistry , cancer , food science , fatty acid , medicine , polyunsaturated fatty acid
To gain some insight into the mechanisms involved in the opposing effects of linoleic acid (LA) and eicosapentaenoic acid (EPA) on the growth and invasiveness of MDA‐MB‐435 human breast cancer cells, the dynamics of the uptake by cells and the incorporation of [ 14 C]LA and [ 14 C]EPA into major lipid and phospholipid pools, as well as the effects of unlabeled EPA or LA on the uptake and distribution of [ 14 C]LA or [ 14 C]EPA, respectively, were examined. Cells were exposed to [ 14 C]LA (1.28 μg/mL) or [ 14 C]EPA (1.0 μg/mL) and unlabeled EPA or LA, respectively, at 0, 1, 4 and 16 μg/mL for 24 h in serum‐free media. The uptake of each fatty acid (FA) was linear over time and was not affected by the presence of the opposing FA. For both FA, 80–90% was incorporated into the phospholipid fraction with the remaining 10–20% in neutral lipids. The relative distribution profile of [ 14 C]LA among the phospholipid classes indicated a preferential incorporation into phosphatidylcholine (65%), whereas [ 14 C]EPA was mostly found in phosphatidylethanolamine (58%). In the presence of unlabeled EPA or LA at various concentrations, corresponding dose‐dependent shifts of [ 14 C]LA or [ 14 C]EPA from the phospholipid to the neutral lipid pool were noted, which did not alter the relative distribution of the FA among the phospholipid classes. Exogenous exposure to EPA or LA increased its content in membrane phospholipids while concurrently decreasing LA or EPA content, respectively, in a dose‐dependent manner. Arachidonic acid content of membrane phospholipids remained constant. The divergent distribution profiles of LA and EPA within the phospholipid compartment provides some insight into the mechanisms of their opposing effects on MDA‐MB‐435 cell growth and invasiveness. Also, the effects of LA and EPA on the uptake and distribution of their opposing FA shed some light on the mechanisms mediating their competitive effects.