Fenretinide differentially modulates the levels of long- and very long-chain ceramides by downregulating Cers5 enzyme: evidence from bench to bedside.

Long- and very long-chain ceramides (LCCs and VLCCs) are biochemically distinct. LCCs are upregulated whereas VLCCs are downregulated in cystic fibrosis. Fenretinide downregulates the levels of LCCs and upregulates the levels of VLCCs. Fenretinide changes the balance of LCCs and VLCCs by downregulating Cers5 enzyme. Fenretinide and zinc ions cooperate in the modulation of ceramide levels.