Biochem/physiol Actions

Autophinib is an ATP-competitive, potent and selective PI3K type 3 lipid kinase vacuolar protein sorting 34 inhibitor (VPS34 IC50/[ATP] = 19 nM/10 µM & 51 nM/100 µM) that shows significant inhibition against only 45 kinases among a panel of >460 with little or no potency toward mTOR, TBK1 and 12 other phosphatidylinositol kinases (=22% inhibition at 1 µM). Autophinib effectively prevents autophagy induction in MCF7 cells upon amino acid starvation or rapamycin treatment (IC50 = 40 nM and 19 nM, respectively) with similar potency as SAR405 (IC50 = 53 nM and 20 nM, respectively) and VPS34-IN1 (IC50 = 13 nM and 15 nM, respectively). Autophinib enhances MCF7 cell death under starvation condition (EC50 = 264 nM and 234 nM by cytotoxiciy and apoptosis detection, respectively) by preventing autophagy-dependent cell survival.