ABSTRACT
We recently described several highly potent, triazine (1) and triazolopyrimidine (2) scaffold-based, dual PI3K/mTOR-inhibitors (e.g., 1, PKI-587) that were efficacious in both in vitro and in vivo models. In order to further optimize these compounds we devised a novel series, the 2-oxatriazines, which also exhibited excellent potency and good metabolic stability. Some 2-oxatriazines showed promising in vivo biomarker suppression and induced apoptosis in the MDA-MB-361 breast cancer xenograft model.
Subject(s)
Phosphoinositide-3 Kinase Inhibitors , Protein Kinase Inhibitors/pharmacology , TOR Serine-Threonine Kinases/antagonists & inhibitors , Triazines/pharmacology , Animals , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Mice , Mice, Nude , Models, Molecular , Molecular Structure , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/metabolism , Rats , Stereoisomerism , Structure-Activity Relationship , Triazines/chemistry , Triazines/metabolismABSTRACT
PKI-402 is a selective, reversible, ATP-competitive, equipotent inhibitor of class I phosphatidylinositol 3-kinases (PI3K), including PI3K-alpha mutants, and mammalian target of rapamycin (mTOR; IC(50) versus PI3K-alpha = 2 nmol/L). PKI-402 inhibited growth of human tumor cell lines derived from breast, brain (glioma), pancreas, and non-small cell lung cancer tissue and suppressed phosphorylation of PI3K and mTOR effector proteins (e.g., Akt at T308) at concentrations that matched those that inhibited cell growth. In MDA-MB-361 [breast: Her2(+) and PIK3CA mutant (E545K)], 30 nmol/L PKI-402 induced cleaved poly(ADP-ribose) polymerase (PARP), a marker for apoptosis. In vivo, PKI-402 inhibited tumor growth in MDA-MB-361, glioma (U87MG), and lung (A549) xenograft models. In MDA-MB-361, PKI-402 at 100 mg/kg (daily for 5 days, one round) reduced initial tumor volume of 260 mm(3) to 129 mm(3) and prevented tumor regrowth for 70 days. In MDA-MB-361 tumors, PKI-402 (100 mg/kg, single dose) suppressed Akt phosphorylation (at T308) and induced cleaved PARP. Suppression of phosphorylated Akt (p-Akt) was complete at 8 hours and still evident at 24 hours. Cleaved PARP was evident at 8 and 24 hours. In normal tissue (heart and lung), PKI-402 (100 mg/kg) had minimal effect on p-Akt, with no detectable cleaved PARP. Preferential accumulation of PKI-402 in tumor tissue was observed. Complete, sustained suppression of Akt phosphorylation may cause tumor regression in MDA-MB-361 and other xenograft models. We are testing whether dual PI3K/mTOR inhibitors can durably suppress p-Akt, induce cleaved PARP, and cause tumor regression in a diverse set of human tumor xenograft models. Mol Cancer Ther; 9(4); 976-84. (c)2010 AACR.
Subject(s)
Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Phenylurea Compounds/pharmacology , Phosphoinositide-3 Kinase Inhibitors , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Pyrimidines/pharmacology , Xenograft Model Antitumor Assays , Animals , Biomarkers, Tumor/metabolism , Caspases/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Enzyme Activation/drug effects , Enzyme Assays , Forkhead Transcription Factors/metabolism , Green Fluorescent Proteins/metabolism , Humans , Inhibitory Concentration 50 , Mice , Phenylurea Compounds/blood , Phenylurea Compounds/chemistry , Poly(ADP-ribose) Polymerases/metabolism , Protein Kinase Inhibitors/blood , Protein Kinase Inhibitors/chemistry , Proto-Oncogene Proteins c-akt/metabolism , Pyrimidines/blood , Pyrimidines/chemistry , TOR Serine-Threonine KinasesABSTRACT
The synthesis and stereochemical determination of 1-(4-(4-((1R,5R,6R)-6-hydroxy-3-oxa-8-azabicyclo[3.2.1]octan-8-yl)-6-morpholino-1,3,5-triazin-2-yl)phenyl)-3-(pyridin-4-yl)urea (2), an active metabolite of the potent PI3 kinase inhibitor PKI-179 (1), is described. Stereospecific hydroboration of the double bond of 2,5-dihydro-1H-pyrrole 8 gave the 2,3-trans alcohol 9 exclusively. The configuration of the 3-hydroxyl group in 9 was inverted by an oxidation and stereoselective reduction sequence to give the corresponding 2,3-cis isomer 23. Both exo (21) and endo (27) isomers of the metabolite 2 were prepared via a practical synthetic route from 9 and 23, respectively, and the stereochemistry of 2 was determined to be endo. The endo isomer (27) was separated into two enantiomers 28 and 29 by chiral HPLC. Compound 2 was found to be enantiomerically pure and identical to the enantiomer 28. The absolute stereochemistry of the enantiomer 28 was determined by Mosher's method, thus establishing the stereochemistry of the active metabolite 2.
Subject(s)
Bridged-Ring Compounds/chemical synthesis , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/chemical synthesis , Morpholines/chemical synthesis , Phosphoinositide-3 Kinase Inhibitors , Urea/analogs & derivatives , Binding Sites , Bridged-Ring Compounds/chemistry , Enzyme Inhibitors/pharmacology , Molecular Structure , Morpholines/chemistry , Morpholines/pharmacology , Oxidation-Reduction , Phosphatidylinositol 3-Kinases/chemistry , Stereoisomerism , Urea/chemical synthesis , Urea/chemistry , Urea/pharmacologyABSTRACT
The PI3K/Akt signaling pathway is a key pathway in cell proliferation, growth, survival, protein synthesis, and glucose metabolism. It has been recognized recently that inhibiting this pathway might provide a viable therapy for cancer. A series of bis(morpholino-1,3,5-triazine) derivatives were prepared and optimized to provide the highly efficacious PI3K/mTOR inhibitor 1-(4-{[4-(dimethylamino)piperidin-1-yl]carbonyl}phenyl)-3-[4-(4,6-dimorpholin-4-yl-1,3,5-triazin-2-yl)phenyl]urea 26 (PKI-587). Compound 26 has shown excellent activity in vitro and in vivo, with antitumor efficacy in both subcutaneous and orthotopic xenograft tumor models when administered intravenously. The structure-activity relationships and the in vitro and in vivo activity of analogues in this series are described.
Subject(s)
Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Phosphoinositide-3 Kinase Inhibitors , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Triazines/pharmacology , Adenosine Triphosphate/chemistry , Adenosine Triphosphate/pharmacology , Animals , Area Under Curve , Binding, Competitive , Cell Line, Tumor , Cell Survival/drug effects , Female , Humans , Inhibitory Concentration 50 , Intracellular Signaling Peptides and Proteins/metabolism , Mice , Mice, Nude , Models, Chemical , Models, Molecular , Molecular Structure , Morpholines/chemistry , Morpholines/pharmacokinetics , Morpholines/pharmacology , Mutation , Neoplasms/metabolism , Neoplasms/pathology , Neoplasms/prevention & control , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Protein Binding , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacokinetics , Protein Serine-Threonine Kinases/metabolism , Protein Structure, Tertiary , Structure-Activity Relationship , Survival Analysis , TOR Serine-Threonine Kinases , Triazines/chemistry , Triazines/pharmacokinetics , Xenograft Model Antitumor AssaysABSTRACT
Herein we describe the identification and lead optimization of triazolopyrimidines as a novel class of potent dual PI3K/mTOR inhibitors, resulting in the discovery of 3 (PKI-402). Compound 3 exhibits good physical properties and PK parameters, low nanomolar potency against PI3Kalpha and mTOR, and excellent inhibition of cell proliferation in several human cancer cell lines. Furthermore, in vitro and in vivo biomarker studies demonstrated the ability of 3 to shut down the PI3K/Akt pathway and induce apoptosis in cancer cells. In addition, 3 showed excellent in vivo efficacy in various human cancer xenografts, validating suppression of PI3K/mTOR signaling as a potential anticancer therapy.
Subject(s)
Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Phosphoinositide-3 Kinase Inhibitors , Protein Serine-Threonine Kinases/antagonists & inhibitors , Pyrimidines/chemical synthesis , Triazoles/chemical synthesis , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Class Ib Phosphatidylinositol 3-Kinase , Humans , Isoenzymes/antagonists & inhibitors , Pyrimidines/pharmacology , Rats , TOR Serine-Threonine Kinases , Triazoles/pharmacology , Xenograft Model Antitumor AssaysABSTRACT
We are introducing a novel series of 2,4-diaminoquinazolines as beta-catenin/Tcf4 inhibitors which were identified by ligand-based design. Here we elucidate the SAR of this series and explain how we were able to improve key molecular properties such as solubility and cLogP leading to compound 9. Analogue 9 exhibited better biological activity and improved physical and pharmacological properties relative to the HTS hit 49. Furthermore, 9 demonstrated good cell growth inhibition against several human colorectal cancer lines such as LoVo and HT29. In addition, treatment with compound 9 led to gene expression changes that overlapped significantly with the transcriptional profile resulting from the pathway inhibition by siRNA knockdown of beta-catenin or Tcf4. Subsequently, 9 was tested for efficacy in a beta-catenin/RKE-mouse xenograft, where it led to more then 50% decrease in tumor volume.
Subject(s)
Colorectal Neoplasms/drug therapy , Quinazolines/chemical synthesis , TCF Transcription Factors/drug effects , beta Catenin/drug effects , Animals , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/drug effects , Cell Line, Tumor , Colorectal Neoplasms/pathology , Drug Design , Humans , Mice , Quinazolines/pharmacology , Quinazolines/therapeutic use , Structure-Activity Relationship , Transcription Factor 4 , Transcription Factors/drug effects , Treatment Outcome , Xenograft Model Antitumor AssaysABSTRACT
The synthesis and SAR of a series of 2,4-diamino-quinazoline derivatives as beta-catenin/Tcf-4 inhibitors are described. This series was developed by modifying the initial lead 1, which was identified by screening of our compound library and found to inhibit the beta-catenin/Tcf-4 pathway. Replacement of the biphenyl moiety in compound 1 with the N-phenylpiperidine-4-carboxamide chain as in 2, resulted in a number of new analogues, which are potent inhibitors of the beta-catenin/Tcf-4 pathway. Compound such as 16k exhibited good cellular potency, solubility, metabolic stability and oral bioavailability.
Subject(s)
Anilides/chemistry , Antineoplastic Agents/chemistry , Colorectal Neoplasms/drug therapy , Quinazolines/chemistry , TCF Transcription Factors/antagonists & inhibitors , beta Catenin/antagonists & inhibitors , Anilides/chemical synthesis , Anilides/pharmacokinetics , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacokinetics , Cell Line, Tumor , Female , Humans , Mice , Mice, Nude , Quinazolines/chemical synthesis , Quinazolines/pharmacokinetics , Structure-Activity Relationship , TCF Transcription Factors/metabolism , Wnt Proteins/antagonists & inhibitors , Wnt Proteins/metabolism , Xenograft Model Antitumor Assays , beta Catenin/metabolismABSTRACT
A series of benzodiazepine MMP/TACE inhibitors bearing polar moieties has been synthesized in an effort to optimize inhibitory activity against LPS-stimulated TNF production in human monocytes and oral activity in a murine LPS model.
Subject(s)
Benzodiazepines/pharmacology , Enzyme Inhibitors/pharmacology , Matrix Metalloproteinase Inhibitors , Metalloendopeptidases/antagonists & inhibitors , ADAM Proteins , ADAM17 Protein , Animals , Cell Line , Enzyme Inhibitors/pharmacokinetics , Humans , Lipopolysaccharides/pharmacology , Mice , Mice, Inbred BALB C , Monocytes/drug effects , Monocytes/metabolism , Mouth/drug effects , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tumor Necrosis Factor-alpha/biosynthesisABSTRACT
A series of benzodiazepine inhibitors of the MMPs and TACE has been developed. These compounds display an interesting selectivity profile and should be useful tools for exploring the biological relevance of such selectivity.
