ABSTRACT
Hepatocellular carcinoma (HCC) accounts for a majority of primary liver cancer and is one of the most common forms of cancer worldwide. Aberrant signaling of the FGF19-FGFR4 pathway leads to HCC in mice and is hypothesized to be a driver in FGF19 amplified HCC in humans. Multiple small molecule inhibitors have been pursued as targeted therapies for HCC in recent years, including several selective FGFR4 inhibitors that are currently being evaluated in clinical trials. Herein, we report a novel series of highly selective, covalent 2-amino-6,8-dimethyl-pyrido[2,3-d]pyrimidin-7(8H)-ones that potently and selectively inhibit FGFR4 signaling through covalent modification of Cys552, which was confirmed by X-ray crystallography. Correlative target occupancy and pFGFR4 inhibition were observed in vivo, as well as tumor regression in preclinical models of orthotopic and sorafenib-resistant HCC.
ABSTRACT
N-substituted azaindoles were discovered as promising pan-PIM inhibitors. Lead optimization is described en route toward the identification of a clinical candidate. Modulation of physico-chemical properties allowed to solve inherent hERG and permeability liabilities. Compound 17 showed tumor growth inhibition in a KG1 tumor-bearing mouse model.
Subject(s)
Antineoplastic Agents/pharmacology , Drug Discovery , Indoles/pharmacology , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-pim-1/antagonists & inhibitors , Animals , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Indoles/administration & dosage , Indoles/chemistry , Mice , Molecular Structure , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/chemistry , Proto-Oncogene Proteins c-pim-1/metabolism , Rats , Structure-Activity RelationshipABSTRACT
Activating KRAS mutations are major oncogenic drivers in multiple tumor types. Synthetic lethal screens have previously been used to identify targets critical for the survival of KRAS mutant cells, but their application to drug discovery has proven challenging, possibly due in part to a failure of monolayer cultures to model tumor biology. Here, we report the results of a high-throughput synthetic lethal screen for small molecules that selectively inhibit the growth of KRAS mutant cell lines in soft agar. Chemoproteomic profiling identifies the target of the most KRAS-selective chemical series as dihydroorotate dehydrogenase (DHODH). DHODH inhibition is shown to perturb multiple metabolic pathways. In vivo preclinical studies demonstrate strong antitumor activity upon DHODH inhibition in a pancreatic tumor xenograft model.
Subject(s)
Oxidoreductases Acting on CH-CH Group Donors/metabolism , Pancreatic Neoplasms/drug therapy , Proto-Oncogene Proteins p21(ras)/metabolism , Pyrimidines/metabolism , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Proliferation/drug effects , Dihydroorotate Dehydrogenase , Drug Screening Assays, Antitumor , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Female , Humans , Mice , Mice, SCID , Mutation , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Oxidoreductases Acting on CH-CH Group Donors/antagonists & inhibitors , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/pathology , Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors , Proto-Oncogene Proteins p21(ras)/genetics , Pyrimidines/chemistry , Small Molecule Libraries/chemistry , Small Molecule Libraries/pharmacology , Tumor Cells, CulturedABSTRACT
N-Substituted azaindoles have been discovered as pan-PIM kinase inhibitors. Initial SAR, early ADME and PK/PD data of a series of compounds is described and led to the identification of promising pan-PIM inhibitors which validated our interest in the 7-azaindole scaffold and led us to pursue the identification of a clinical candidate.
Subject(s)
Indoles/chemistry , Indoles/pharmacology , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-pim-1/metabolism , Animals , Crystallography, X-Ray , Drug Evaluation, Preclinical , Enzyme Activation/drug effects , Half-Life , Humans , Indoles/metabolism , Inhibitory Concentration 50 , Mice , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Protein Kinase Inhibitors/metabolism , Protein Kinase Inhibitors/pharmacokinetics , Proto-Oncogene Proteins c-pim-1/chemistry , Rats , Structure-Activity RelationshipABSTRACT
Beginning with a screening hit, unique thienopyrazole-indole inhibitors of Itk (interleukin-2-inducible tyrosine kinase) were designed, synthesized, and crystallized in the target kinase. Although initial compounds were highly active in Itk, they were not selective. Increasing the steric bulk around a tertiary alcohol at the 5-indole position dramatically improved selectivity toward Lyk and Syk, but not Txk. Substitutions at the 3- and 4-indole positions gave less active compounds that remained poorly selective. A difluoromethyl substitution at the 5-position of the thienopyrazole led to a highly potent and selective compound. Phenyl at this position reduced activity and selectivity while pushing the side-chains of Lys-391 and Asp-500 away from the binding pocket. Novel and selective thienopyrazole inhibitors of Itk were designed as a result of combining structure-based design and medicinal chemistry.
Subject(s)
Drug Design , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Protein-Tyrosine Kinases/antagonists & inhibitors , Pyrazoles/chemistry , Pyrazoles/pharmacology , Crystallography, X-Ray , Humans , Structure-Activity RelationshipABSTRACT
A study designed to assess the diastereoselectivity of the intramolecular aldol reaction of two differently sized monocyclic 1,3-diketones bearing a chiral, oxygenated side chain has been undertaken. The cyclizations were brought about under catalysis by pyrrolidine, a series of D- and L-amino acids including proline, and several proline derivatives. The levels of selectivity were found to be consistently higher with the six-membered ring system than its cycloheptane counterpart.
