ABSTRACT
SLK (STE20-like kinase) and STK10 (serine/threonine kinase 10) are closely related kinases whose enzymatic activity is linked to the regulation of ezrin, radixin, and moesin function and to the regulation of lymphocyte migration and the cell cycle. We identified a series of 3-anilino-4-arylmaleimides as dual inhibitors of SLK and STK10 with good kinome-wide selectivity. Optimization of this series led to multiple SLK/STK10 inhibitors with nanomolar potency. Crystal structures of exemplar inhibitors bound to SLK and STK10 demonstrated the binding mode of the inhibitors and rationalized their selectivity. Cellular target engagement assays demonstrated the binding of the inhibitors to SLK and STK10 in cells. Further selectivity analyses, including analysis of activity of the reported inhibitors against off-targets in cells, identified compound 31 as the most potent and selective inhibitor of SLK and STK10 yet reported.
Subject(s)
Aniline Compounds/pharmacology , Maleimides/pharmacology , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Aniline Compounds/chemistry , Aniline Compounds/metabolism , Binding Sites , Cell Line, Tumor , Cell Movement/drug effects , HEK293 Cells , Humans , Maleimides/chemistry , Maleimides/metabolism , Microfilament Proteins/metabolism , Molecular Docking Simulation , Molecular Structure , Phosphorylation/drug effects , Protein Binding , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/metabolism , Protein Serine-Threonine Kinases/chemistry , Protein Serine-Threonine Kinases/metabolism , Structure-Activity RelationshipABSTRACT
The recent disclosure of type I 1/2 inhibitors for p38α MAPK demonstrated how the stabilization of the R-spine can be used as a strategy to greatly increase the target residence time (TRT) of inhibitors. Herein, for the first time, we describe N-acylhydrazone and selenophene residues as spine motifs, yielding metabolically stable inhibitors with high potency on enzymatic, NanoBRET, and whole blood assays, improved metabolic stability, and prolonged TRT.
Subject(s)
Dibenzocycloheptenes/chemistry , Mitogen-Activated Protein Kinase 14/antagonists & inhibitors , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Structure-Activity Relationship , Amides/chemistry , Drug Design , Drug Stability , Humans , Hydrazones/chemistry , Microsomes, Liver/drug effects , Mitogen-Activated Protein Kinase 14/chemistry , Mitogen-Activated Protein Kinase 14/metabolism , Organoselenium Compounds/chemistry , Protein Kinase Inhibitors/pharmacokinetics , Time FactorsABSTRACT
Gastric cancer (GC) remains the third leading cause of cancer-related death despite several improvements in targeted therapy. There is therefore an urgent need to investigate new treatment strategies, including the identification of novel biomarkers for patient stratification. In this study, we evaluated the effect of FDA-approved kinase inhibitors on GC. Through a combination of cell growth, migration and invasion assays, we identified dasatinib as an efficient inhibitor of GC proliferation. Mass-spectrometry-based selectivity profiling and subsequent knockdown experiments identified members of the SRC family of kinases including SRC, FRK, LYN and YES, as well as other kinases such as DDR1, ABL2, SIK2, RIPK2, EPHA2, and EPHB2 as dasatinib targets. The expression levels of the identified kinases were investigated on RNA and protein level in 200 classified tumor samples from patients, who had undergone gastrectomy, but had received no treatment. Levels of FRK, DDR1 and SRC expression on both mRNA and protein level were significantly higher in metastatic patient samples regardless of the tumor stage, while expression levels of SIK2 correlated with tumor size. Collectively, our data suggest dasatinib for treatment of GC based on its unique property, inhibiting a small number of key kinases (SRC, FRK, DDR1 and SIK2), highly expressed in GC patients.