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Updated: May 4, 2026

Kinase Inhibitor Screening In Self-assembled Human Protein Microarrays
Published on: October 23, 2019
Back pocket flexibility provides group II p21-activated kinase (PAK) selectivity for type I 1/2 kinase inhibitors
Steven T Staben1, Jianwen A Feng, Karen Lyle
1Department of Discovery Chemistry, ‡Department of Translational Oncology, △Department of Pathology, §Department of Drug Metabolism and Pharmacokinetics, ∥Department of Biochemical and Cellular Pharmacology, and ⊥Department of Structural Biology, Genentech, Inc. , 1 DNA Way, South San Francisco, California 94080, United States.
Abstract:
Structure-based methods were used to design a potent and highly selective group II p21-activated kinase (PAK) inhibitor with a novel binding mode, compound 17. Hydrophobic interactions within a lipophilic pocket past the methionine gatekeeper of group II PAKs approached by these type I 1/2 binders were found to be important for improving potency. A structure-based hypothesis and strategy for achieving selectivity over group I PAKs, and the broad kinome, based on unique flexibility of this lipophilic pocket, is presented. A concentration-dependent decrease in tumor cell migration and invasion in two triple-negative breast cancer cell lines was observed with compound 17.
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