Human breast cancer cells stably expressed FADS2 synthesize sapienic acid (16:1n-10) from palmitic acid (16:0) (821.8)

Introduction. Sapienic acid, 16:1n-10, is synthesized in sebocytes and is the most abundant unsaturated fatty on human skin. Its biosynthesis from palmitic acid (16:0) has not been demonstrated apart from skin glands. MCF-7 human breast cancer cells have no detectable 6-desaturase activity despite detectable FADS2 expression. Our aim was to characterize the fatty acid profile of MCF-7 cells stably expressing FADS2 grown in MEM-α media containing 16:0, 18:2n-6, 18:3n-3, and long chain PUFA. Methods. Cells stably expressing FADS2, FADS1, and empty vector were created by using pcDNA3.1 expression vector system. At confluence cells were dosed with 100 μM of albumin-bound 16:0 fatty acid. Cells were harvested after 24 hours, FAME were analyzed by GC and structures confirmed by CACI-MS/MS. Results. FADS2 MCF-7 cells preferentially biosynthesize 16:1n-10 which is more abundant than 16:1n-9. The two fatty acids have nearly identical retention times under our standard GC conditions. No synthesis of 16:1n-10 was ob...