Conjugated linoleic acid alters caveolae phospholipid fatty acid composition and decreases caveolin-1 expression in MCF-7 breast cancer cells

• Published in: Nutrition research (New York, N.Y.) Vol. 30; no. 3; pp. 179 - 185
• Main Authors: Huot, Pedro S.P, Sarkar, Baisakhi, Ma, David W.L
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01-03-2010; Tarrytown, N.Y.: Elsevier Science Inc; Elsevier
• Subjects: Biological and medical sciences; Breast; breast neoplasms; Breast Neoplasms - chemistry; Breast Neoplasms - ultrastructure; Cancer; Caveolae; Caveolae - chemistry; Caveolae - drug effects; Caveolae - metabolism; Caveolin 1 - analysis; Caveolin-1; Cell Line, Tumor; Conjugated linoleic acid; fatty acid composition; Fatty acids; Fatty Acids - analysis; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Gastroenterology and Hepatology; human cell lines; human diseases; human nutrition; Humans; Linoleic acid; Linoleic Acids, Conjugated - metabolism; Linoleic Acids, Conjugated - pharmacology; Lipids; MCF-7 cancer cells; membrane proteins; Membranes; Nutrition; Phospholipids; Phospholipids - analysis; Phospholipids - metabolism; plasma membrane; protein synthesis; Proteins; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Caveolin-1; 9,11-CLA; MUFA; polyunsaturated fatty acids; t,t-CLA; Phospholipids; PtdSer; choline glycerophospholipid; c,c-CLA; Caveolae; plasma membrane; PUFA; Δ9 cis,11 trans-18:2; CL; human epidermal growth factor receptor 2; monounsaturated fatty acids; 10,12-CLA; Linoleic acid; cell lysate; EtnGpl; phosphatidylserine; conjugated linoleic acid; LA; ChoGpl; linoleic acid (Δ9 cis,12 cis-18:2); trans, trans isomers of CLA; CLA; ethanolamine glycerophospholipid; Δ10 trans,12 cis-18:2; MCF-7 cancer cells; Her-2; cis, cis isomers of CLA; PM; Conjugated linoleic acid; Breast disease; Phospholipid; Lipids; Breast cancer; Malignant tumor; Gene expression; Fatty acids; Mammary gland diseases; Vertebrata; Caveolin 1; Mammalia; Decrease; Cancer
• ISSN: 0271-5317; 1879-0739
• DOI: 10.1016/j.nutres.2010.02.003

Abstract Conjugated linoleic acid (CLA) refers to a group of biologically active fatty acids that exhibit anticarcinogenic properties; however, the mechanism of action remains poorly understood. Caveolae are specialized plasma membrane structures that affect many facets of cancer cell function, including growth, cell signaling, and apoptosis. Therefore, one potential mechanism could be alteration of caveolae lipid composition and function. We hypothesized that CLA can alter the lipid microenvironment of caveolae and alter expression of the major caveolae-resident protein, caveolin-1. MCF-7 human breast cancer cells were treated with a vehicle control, linoleic acid (LA), or CLA for 3 days after which total cell lysate, plasma membrane, and caveolae membrane fractions were isolated. Our findings indicate that CLA readily incorporates into caveolae (Δ9 cis ,11 trans -18:2 being the major isomer) and maybe preferentially enriched in specific phospholipid species. Furthermore, caveolin-1 localization to caveolae after treatment with CLA was decreased relative to either control- or LA-treated cells, without changes in total cellular levels of protein relative to vehicle-control treated cells. Taken together, our results suggest that further investigation of a potential therapeutic role for CLA in modulating caveolae function in breast cancer is merited.