Pharmacophore development and application toward the identification of novel, small-molecule autotaxin inhibitors

Autotaxin (ATX) is a secreted glycoprotein with lysophospholipase D (LPLD) activity that generates the bioactive lipid lysophosphatidic acid (LPA) from lysophosphatidylcholine (LPC). Both ATX and LPA have been linked to the promotion and progression of cancer as well as cardiovascular disease and obesity. Despite the fact that ATX inhibitors have the potential to be useful chemotherapeutics for multiple indications, few examples of potent ATX inhibitors are described in the current literature. Here we describe the development of pharmacophore models for the inhibition of ATX by nonlipids and apply these tools to the discovery of additional ATX inhibitors using the NCI open chemical repository database. From this database of > 250,000 compounds, 168 candidate inhibitors were identified. Of these candidates, 106 were available for testing and 33 were identified as active (those that inhibited ATX activity by > or =50% at a single 10 microM concentration), a 31% hit rate. Five of these compounds had IC(50) < 1.5 microM and the most potent compound possessed a K(i) of 271 nM.