A new pathway leading to the n-10
fatty acid series has been recently evidenced, starting from
sapienic acid, a
monounsaturated fatty acid (MUFA) resulting from the transformation of
palmitic acid by delta-6 desaturase.
Sapienic acid has attracted attention as a novel marker of
cancer cell plasticity. Here, we analyzed
fatty acids, including the n-10
fatty acid contents, and for the first time, compared cell membranes and the corresponding extracellular vesicles (EV) of two human prostatic
adenocarcinoma cell lines of different aggressiveness (PC3 and LNCaP). The n-10 components were 9-13% of the total
fatty acids in both
cancer cell lines and EVs, with total MUFA levels significantly higher in EVs of the most aggressive cell type (PC3). High sapienic/palmitoleic ratios indicated the preference for delta-6 versus
delta-9 desaturase enzymatic activity in these cell lines. The expressions analysis of
enzymes involved in desaturation and elongation by qRT-PCR showed a higher desaturase activity in PC3 and a higher elongase activity toward
polyunsaturated fatty acids than toward
saturated fatty acids, compared to LNCaP cells. Our results improve the present knowledge in
cancer fatty acid metabolism and
lipid phenotypes, highlighting EV lipidomics to monitor positional
fatty acid isomer profiles and MUFA levels in
cancer.