Deconvolution of Buparlisib's mechanism of action defines specific PI3K and tubulin inhibitors for therapeutic intervention.Bohnacker, T., Prota, A.E., Beaufils, F., Burke, J.E., Melone, A., Inglis, A.J., Rageot, D., Sele, A.M., Cmiljanovic, V., Cmiljanovic, N., Bargsten, K., Aher, A., Akhmanova, A., Diaz, J.F., Fabbro, D., Zvelebil, M., Williams, R.L., Steinmetz, M.O., Wymann, M.P.
(2017) Nat Commun 8: 14683-14683
- PubMed: 28276440
- DOI: 10.1038/ncomms14683
- Primary Citation of Related Structures:
- PubMed Abstract:
BKM120 (Buparlisib) is one of the most advanced phosphoinositide 3-kinase (PI3K) inhibitors for the treatment of cancer, but it interferes as an off-target effect with microtubule polymerization. Here, we developed two chemical derivatives that diffe ...
BKM120 (Buparlisib) is one of the most advanced phosphoinositide 3-kinase (PI3K) inhibitors for the treatment of cancer, but it interferes as an off-target effect with microtubule polymerization. Here, we developed two chemical derivatives that differ from BKM120 by only one atom. We show that these minute changes separate the dual activity of BKM120 into discrete PI3K and tubulin inhibitors. Analysis of the compounds cellular growth arrest phenotypes and microtubule dynamics suggest that the antiproliferative activity of BKM120 is mainly due to microtubule-dependent cytotoxicity rather than through inhibition of PI3K. Crystal structures of BKM120 and derivatives in complex with tubulin and PI3K provide insights into the selective mode of action of this class of drugs. Our results raise concerns over BKM120's generally accepted mode of action, and provide a unique mechanistic basis for next-generation PI3K inhibitors with improved safety profiles and flexibility for use in combination therapies.
PIQUR Therapeutics AG, 4057 Basel, Switzerland.,MRC Laboratory of Molecular Biology, Cambridge CB2 2QH, UK.,Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia BC V8W 2Y2, Canada.,Cell Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, The Netherlands.,Department of Biomedicine, University of Basel, 4058 Basel, Switzerland.,Laboratory of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland.,CIB Centro de Investigaciones Biológicas, 28040 Madrid, Spain.,The Institute of Cancer Research, London SW3 6JB, UK.