Conjugated linoleic acid (CLA)-enriched milk fat inhibits growth and modulates CLA-responsive biomarkers in MCF-7 and SW480 human cancer cell lines

Br J Nutr. 2003 Nov;90(5):877-85. doi: 10.1079/bjn2003978.

Abstract

Milk enriched in conjugated linoleic acid (CLA) was obtained from cows on pasture supplemented with full-fat rapeseeds (FFR; 2.26 g cis 9, trans 11 (c9,t11)-CLA/100 g fatty acid methyl esters) and full-fat soyabeans (1.83 g c9,t11-CLA100 g fatty acid methyl esters). A control milk fat (1.69 g c9,t11-CLA/100 g fatty acid methyl esters) was obtained from cows fed on pasture only. The present study assessed the potency of the CLA-enriched milk fats to modulate biomarkers that had previously been observed to respond to c9,t11-CLA in the MCF-7 and SW480 cell lines. Cell numbers decreased (P<0.05) by up to 61 and 58% following the incubation of MCF-7 and SW480 cells, respectively, for 4 d with milk fats (yielding CLA concentrations between 60.2 and 80.6 microM). The FFR milk fat, containing the highest CLA content, increased (P<0.05) [14C]arachidonic acid (AA) uptake into the monoacylglycerol fraction of MCF-7 and SW480 cells while it decreased (P<0.05) uptake into the phospholipid fraction of the latter. This milk fat also decreased (P<0.05) [14C]AA conversion to prostaglandin (PG) E2 while increasing conversion to PGF2alpha in both cell lines. All milk-fat samples increased (P<0.05) lipid peroxidation as measured by 8-epi-PGF2alpha in both cell lines. In SW480 cells the milk-fat samples decreased (P<0.05) bcl-2 and cytosolic glutathione levels while increasing (P<0.05) membrane-associated annexin V levels. All milk-fat samples decreased (P<0.05) the expression of ras in SW480 cells. These data suggest that milk-fat CLA was effective at modulating synthetic CLA-responsive biomarkers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Annexin A5 / analysis
  • Apoptosis / physiology
  • Arachidonic Acid / metabolism
  • Biomarkers
  • Cell Count
  • Cell Division / physiology
  • Cell Line, Tumor
  • Dietary Fats / metabolism*
  • Dinoprost / analogs & derivatives*
  • Dinoprost / biosynthesis
  • Eicosanoids / metabolism
  • Gene Expression / genetics
  • Genes, bcl-2 / genetics
  • Genes, ras / genetics
  • Glutathione / analysis
  • Humans
  • Linoleic Acids, Conjugated / metabolism*
  • Lipid Peroxidation / physiology
  • Milk / metabolism*

Substances

  • Annexin A5
  • Biomarkers
  • Dietary Fats
  • Eicosanoids
  • Linoleic Acids, Conjugated
  • 8-epi-prostaglandin F2alpha
  • Arachidonic Acid
  • Dinoprost
  • Glutathione