CERS1 and neoplasm: The most highly expressed CerS in the central nervous system is CerS1, which generates mainly ceramides with a fatty acid chain containing 18 C-atoms (C18-ceramide); higher abundance of fatty acids with longer and shorter chains in ceramides of tumor cells is a result of higher activity of particular CerSs, such as CerS2, which predominantly catalyze the biosynthesis of ceramides containing very long-chain fatty acids with 22 and 24 C-atoms [44].