Distinction between 2′- and 3′-Phosphate Isomers of a Fluorescent NADPH Analogue Led to Strong Inhibition of Cancer Cells Migration

Nom de la revue
Antioxidants
Raoul Manuel, Michelle de Souza Lima, Sébastien Dilly, Sylvain Daunay, Patricia Abbe, Elodie Pramil, Stéphanie Solier, Fabienne Guillaumond, Sarah-Simha Tubiana, Alexandre Escargueil, João Antonio Pêgas Henriques, Nathalie Ferrand, Irène Erdelmeier, Jean-Luc Boucher, Gildas Bertho, Israel Agranat, Stéphane Rocchi, Michèle Sabbah, Anny Slama Schwok
Abstract

Specific inhibition of NADPH oxidases (NOX) and NO-synthases (NOS), two enzymes associated with redox stress in tumor cells, has aroused great pharmacological interest. Here, we show how these enzymes distinguish between isomeric 2′- and 3′-phosphate derivatives, a difference used to improve the specificity of inhibition by isolated 2′- and 3′-phosphate isomers of our NADPH analogue NS1. Both isomers become fluorescent upon binding to their target proteins as observed by in vitro assay and in vivo imaging. The 2′-phosphate isomer of NS1 exerted more pronounced effects on NOS and NOX-dependent physiological responses than the 3′-phosphate isomer did. Docking and molecular dynamics simulations explain this specificity at the level of the NADPH site of NOX and NOS, where conserved arginine residues distinguished between the 2′-phosphate over the 3′-phosphate group, in favor of the 2′-phosphate.