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1.
Bioorg Med Chem Lett ; 69: 128782, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35537608

ABSTRACT

11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) has been identified as the primary enzyme responsible for the activation of hepatic cortisone to cortisol in specific peripheral tissues resulting in the concomitant antagonism of insulin action within these tissues. Dysregulation of 11ß-HSD1, particularly in adipose tissues, has been associated with metabolic syndrome and type 2 diabetes mellitus. Therefore, inhibition of 11ß-HSD1 with a small nonsteroidal molecule is therapeutically desirable. Implementation of a scaffold-hopping approach revealed a three-point pharmacophore for 11ß-HSD1 that was utilized to design a steroid mimetic scaffold. Reiterative optimization provided valuable insight into the bioactive conformation of our novel scaffold and led to the discovery of INCB13739. Clinical evaluation of INCB13739 confirmed for the first time that tissue-specific inhibition of 11ß-HSD1 in patients with type 2 diabetes mellitus was efficacious in controlling glucose levels and reducing cardiovascular risk factors.


Subject(s)
Diabetes Mellitus, Type 2 , Metabolic Syndrome , 11-beta-Hydroxysteroid Dehydrogenase Type 1/metabolism , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Enzyme Inhibitors/pharmacology , Humans , Hydrocortisone/metabolism , Metabolic Syndrome/metabolism
2.
J Pharmacol Exp Ther ; 374(1): 211-222, 2020 07.
Article in English | MEDLINE | ID: mdl-32345620

ABSTRACT

The clinical use of first-generation phosphoinositide 3-kinase (PI3K)δ inhibitors in B-cell malignancies is hampered by hepatotoxicity, requiring dose reduction, treatment interruption, and/or discontinuation of therapy. In addition, potential molecular mechanisms by which resistance to this class of drugs occurs have not been investigated. Parsaclisib (INCB050465) is a potent and selective next-generation PI3Kδ inhibitor that differs in structure from first-generation PI3Kδ inhibitors and has shown encouraging anti-B-cell tumor activity and reduced hepatotoxicity in phase 1/2 clinical studies. Here, we present preclinical data demonstrating parsaclisib as a potent inhibitor of PI3Kδ with over 1000-fold selectivity against other class 1 PI3K isozymes. Parsaclisib directly blocks PI3K signaling-mediated cell proliferation in B-cell lines in vitro and in vivo and indirectly controls tumor growth by lessening immunosuppression through regulatory T-cell inhibition in a syngeneic lymphoma model. Diffuse large B-cell lymphoma cell lines overexpressing MYC were insensitive to proliferation blockade via PI3Kδ signaling inhibition by parsaclisib, but their proliferative activities were reduced by suppression of MYC gene transcription. Molecular structure analysis of the first- and next-generation PI3Kδ inhibitors combined with clinical observation suggests that hepatotoxicity seen with the first-generation inhibitors could result from a structure-related off-target effect. Parsaclisib is currently being evaluated in multiple phase 2 clinical trials as a therapy against various hematologic malignancies of B-cell origin (NCT03126019, NCT02998476, NCT03235544, NCT03144674, and NCT02018861). SIGNIFICANCE STATEMENT: The preclinical properties described here provide the mechanism of action and support clinical investigations of parsaclisib as a therapy for B-cell malignancies. MYC overexpression was identified as a resistance mechanism to parsaclisib in DLBCL cells, which may be useful in guiding further translational studies for the selection of patients with DLBCL who might benefit from PI3Kδ inhibitor treatment in future trials. Hepatotoxicity associated with first-generation PI3Kδ inhibitors may be an off-target effect of that class of compounds.


Subject(s)
Liver/drug effects , Lymphoma/pathology , Phosphatidylinositol 3-Kinases/metabolism , Phosphoinositide-3 Kinase Inhibitors/adverse effects , Phosphoinositide-3 Kinase Inhibitors/pharmacology , Pyrazoles/adverse effects , Pyrazoles/pharmacology , Pyrimidines/adverse effects , Pyrimidines/pharmacology , Pyrrolidines/adverse effects , Pyrrolidines/pharmacology , Animals , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Disease Models, Animal , Female , Humans , Immunologic Factors/adverse effects , Immunologic Factors/pharmacology , Mice , Xenograft Model Antitumor Assays
3.
J Pharmacol Exp Ther ; 364(1): 120-130, 2018 01.
Article in English | MEDLINE | ID: mdl-29127109

ABSTRACT

Phosphatidylinositol 3-kinase delta (PI3Kδ) is a critical signaling molecule in B cells and is considered a target for development of therapies against various B cell malignancies. INCB040093 is a novel PI3Kδ small-molecule inhibitor and has demonstrated promising efficacy in patients with Hodgkin's lymphoma in clinical studies. In this study, we disclose the chemical structure and the preclinical activity of the compound. In biochemical assays, INCB040093 potently inhibits the PI3Kδ kinase, with 74- to >900-fold selectivity against other PI3K family members. In vitro and ex vivo studies using primary B cells, cell lines from B cell malignancies, and human whole blood show that INCB040093 inhibits PI3Kδ-mediated functions, including cell signaling and proliferation. INCB040093 has no significant effect on the growth of nonlymphoid cell lines and was less potent in assays that measure human T and natural killer cell proliferation and neutrophil and monocyte functions, suggesting that the impact of INCB040093 on the human immune system will likely be restricted to B cells. INCB040093 inhibits the production of macrophage-inflammatory protein-1ß (MIP-1beta) and tumor necrosis factor-ß (TNF-beta) from a B cell line, suggesting a potential effect on the tumor microenvironment. In vivo, INCB040093 demonstrates single-agent activity in inhibiting tumor growth and potentiates the antitumor growth effect of the clinically relevant chemotherapeutic agent, bendamustine, in the Pfeiffer cell xenograft model of non-Hodgkin's lymphoma. INCB040093 has a favorable exposure profile in rats and an acceptable safety margin in rats and dogs. Taken together, data presented in this report support the potential utility of orally administered INCB040093 in the treatment of B cell malignancies.


Subject(s)
Antineoplastic Agents/pharmacology , Lymphoma, Non-Hodgkin/drug therapy , Neoplasms/drug therapy , Phosphoinositide-3 Kinase Inhibitors , Protein Kinase Inhibitors/pharmacology , Animals , B-Lymphocytes/drug effects , B-Lymphocytes/metabolism , Cell Line , Cell Proliferation/drug effects , Chemokine CCL4/metabolism , Dogs , Female , Humans , Killer Cells, Natural/drug effects , Killer Cells, Natural/metabolism , Lymphoma, Non-Hodgkin/metabolism , Male , Mice , Mice, SCID , Monocytes/drug effects , Monocytes/metabolism , Neoplasms/metabolism , Neutrophils/drug effects , Neutrophils/metabolism , Rats , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism
4.
Blood ; 126(13): 1551-4, 2015 Sep 24.
Article in English | MEDLINE | ID: mdl-26228487

ABSTRACT

The JAK2 c.1849G>T (p.V617F) mutation leads to constitutive activation of Janus kinase (JAK)2 and contributes to dysregulated JAK signaling in myelofibrosis (MF), polycythemia vera (PV), and essential thrombocythemia (ET). In the phase 3 Controlled Myelofibrosis Study with Oral JAK Inhibitor Treatment-I trial, patients with MF, post-PV MF, or post-ET MF achieved significant reductions in splenomegaly and improvements in symptoms with ruxolitinib vs placebo at week 24. This long-term follow-up analysis was performed to determine whether ruxolitinib therapy altered the JAK2p.V617F allele burden in JAK2p.V617F-positive patients. Assessments at baseline and weeks 24, 48, 120, 144, 168, and 216 demonstrated reductions in allele burden from baseline with ruxolitinib treatment that correlated with spleen volume reductions. Of 236 JAK2p.V617F-positive patients analyzed, 20 achieved partial and 6 achieved complete molecular responses, with median times to response of 22.2 and 27.5 months, respectively. Allele burden reductions were greater in patients with shorter disease duration, which suggests a potential benefit of earlier treatment. This trial was registered at www.clinicaltrials.gov as #NCT00952289.


Subject(s)
Janus Kinase 2/antagonists & inhibitors , Janus Kinase 2/genetics , Point Mutation , Primary Myelofibrosis/drug therapy , Primary Myelofibrosis/genetics , Pyrazoles/therapeutic use , Alleles , Female , Humans , Male , Nitriles , Primary Myelofibrosis/complications , Primary Myelofibrosis/pathology , Pyrimidines , Spleen/drug effects , Spleen/metabolism , Spleen/pathology , Splenomegaly/complications , Splenomegaly/drug therapy , Splenomegaly/genetics , Splenomegaly/pathology
5.
Cancer Discov ; 12(6): 1482-1499, 2022 06 02.
Article in English | MEDLINE | ID: mdl-35254416

ABSTRACT

Blocking the activity of the programmed cell death protein 1 (PD-1) inhibitory receptor with therapeutic antibodies against either the ligand (PD-L1) or PD-1 itself has proven to be an effective treatment modality for multiple cancers. Contrasting with antibodies, small molecules could demonstrate increased tissue penetration, distinct pharmacology, and potentially enhanced antitumor activity. Here, we describe the identification and characterization of INCB086550, a novel, oral, small-molecule PD-L1 inhibitor. In vitro, INCB086550 selectively and potently blocked the PD-L1/PD-1 interaction, induced PD-L1 dimerization and internalization, and induced stimulation-dependent cytokine production in primary human immune cells. In vivo, INCB086550 reduced tumor growth in CD34+ humanized mice and induced T-cell activation gene signatures, consistent with PD-L1/PD-1 pathway blockade. Preliminary data from an ongoing phase I study confirmed PD-L1/PD-1 blockade in peripheral blood cells, with increased immune activation and tumor growth control. These data support continued clinical evaluation of INCB086550 as an alternative to antibody-based therapies. SIGNIFICANCE: We have identified a potent small-molecule inhibitor of PD-L1, INCB086550, which has biological properties similar to PD-L1/PD-1 monoclonal antibodies and may represent an alternative to antibody therapy. Preliminary clinical data in patients demonstrated increased immune activation and tumor growth control, which support continued clinical evaluation of this approach. See related commentary by Capparelli and Aplin, p. 1413. This article is highlighted in the In This Issue feature, p. 1397.


Subject(s)
B7-H1 Antigen , Neoplasms , Animals , Humans , Immune Checkpoint Inhibitors , Lymphocyte Activation , Mice , Neoplasms/drug therapy , Programmed Cell Death 1 Receptor
6.
J Med Chem ; 64(15): 10666-10679, 2021 08 12.
Article in English | MEDLINE | ID: mdl-34269576

ABSTRACT

Aberrant activation of FGFR has been linked to the pathogenesis of many tumor types. Selective inhibition of FGFR has emerged as a promising approach for cancer treatment. Herein, we describe the discovery of compound 38 (INCB054828, pemigatinib), a highly potent and selective inhibitor of FGFR1, FGFR2, and FGFR3 with excellent physiochemical properties and pharmacokinetic profiles. Pemigatinib has received accelerated approval from the U.S. Food and Drug Administration for the treatment of adults with previously treated, unresectable locally advanced or metastatic cholangiocarcinoma with a FGFR2 fusion or other rearrangement. Additional clinical trials are ongoing to evaluate pemigatinib in patients with FGFR alterations.


Subject(s)
Drug Discovery , Morpholines/pharmacology , Protein Kinase Inhibitors/pharmacology , Pyrimidines/pharmacology , Pyrroles/pharmacology , Receptor, Fibroblast Growth Factor, Type 1/antagonists & inhibitors , Receptor, Fibroblast Growth Factor, Type 2/antagonists & inhibitors , Receptor, Fibroblast Growth Factor, Type 3/antagonists & inhibitors , Dose-Response Relationship, Drug , Humans , Molecular Structure , Morpholines/chemical synthesis , Morpholines/chemistry , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Pyrroles/chemical synthesis , Pyrroles/chemistry , Receptor, Fibroblast Growth Factor, Type 1/metabolism , Receptor, Fibroblast Growth Factor, Type 2/metabolism , Receptor, Fibroblast Growth Factor, Type 3/metabolism , Structure-Activity Relationship , United States , United States Food and Drug Administration
7.
Nat Commun ; 12(1): 4445, 2021 07 21.
Article in English | MEDLINE | ID: mdl-34290245

ABSTRACT

Immune checkpoint inhibitors demonstrate clinical activity in many tumor types, however, only a fraction of patients benefit. Combining CD137 agonists with these inhibitors increases anti-tumor activity preclinically, but attempts to translate these observations to the clinic have been hampered by systemic toxicity. Here we describe a human CD137xPD-L1 bispecific antibody, MCLA-145, identified through functional screening of agonist- and immune checkpoint inhibitor arm combinations. MCLA-145 potently activates T cells at sub-nanomolar concentrations, even under suppressive conditions, and enhances T cell priming, differentiation and memory recall responses. In vivo, MCLA-145 anti-tumor activity is superior to immune checkpoint inhibitor comparators and linked to recruitment and intra-tumor expansion of CD8 + T cells. No graft-versus-host-disease is observed in contrast to other antibodies inhibiting the PD-1 and PD-L1 pathway. Non-human primates treated with 100 mg/kg/week of MCLA-145 show no adverse effects. The conditional activation of CD137 signaling by MCLA-145, triggered by neighboring cells expressing >5000 copies of PD-L1, may provide both safety and potency advantages.


Subject(s)
4-1BB Ligand/agonists , Antibodies, Bispecific/pharmacology , B7-H1 Antigen/antagonists & inhibitors , CD8-Positive T-Lymphocytes/drug effects , Immune Checkpoint Inhibitors/pharmacology , 4-1BB Ligand/immunology , Animals , Antibodies, Bispecific/immunology , B7-H1 Antigen/immunology , CD8-Positive T-Lymphocytes/immunology , Epitopes , Humans , Immune Checkpoint Inhibitors/immunology , Immune Tolerance/drug effects , Immunologic Memory/drug effects , Immunotherapy , Lymphocyte Activation/drug effects
8.
PLoS One ; 15(4): e0231877, 2020.
Article in English | MEDLINE | ID: mdl-32315352

ABSTRACT

Alterations in fibroblast growth factor receptor (FGFR) genes have been identified as potential driver oncogenes. Pharmacological targeting of FGFRs may therefore provide therapeutic benefit to selected cancer patients, and proof-of-concept has been established in early clinical trials of FGFR inhibitors. Here, we present the molecular structure and preclinical characterization of INCB054828 (pemigatinib), a novel, selective inhibitor of FGFR 1, 2, and 3, currently in phase 2 clinical trials. INCB054828 pharmacokinetics and pharmacodynamics were investigated using cell lines and tumor models, and the antitumor effect of oral INCB054828 was investigated using xenograft tumor models with genetic alterations in FGFR1, 2, or 3. Enzymatic assays with recombinant human FGFR kinases showed potent inhibition of FGFR1, 2, and 3 by INCB054828 (half maximal inhibitory concentration [IC50] 0.4, 0.5, and 1.0 nM, respectively) with weaker activity against FGFR4 (IC50 30 nM). INCB054828 selectively inhibited growth of tumor cell lines with activation of FGFR signaling compared with cell lines lacking FGFR aberrations. The preclinical pharmacokinetic profile suggests target inhibition is achievable by INCB054828 in vivo with low oral doses. INCB054828 suppressed the growth of xenografted tumor models with FGFR1, 2, or 3 alterations as monotherapy, and the combination of INCB054828 with cisplatin provided significant benefit over either single agent, with an acceptable tolerability. The preclinical data presented for INCB054828, together with preliminary clinical observations, support continued investigation in patients with FGFR alterations, such as fusions and activating mutations.


Subject(s)
Morpholines/therapeutic use , Neoplasms/drug therapy , Protein Kinase Inhibitors/therapeutic use , Pyrimidines/therapeutic use , Pyrroles/therapeutic use , Receptor, Fibroblast Growth Factor, Type 1/antagonists & inhibitors , Receptor, Fibroblast Growth Factor, Type 2/antagonists & inhibitors , Receptor, Fibroblast Growth Factor, Type 3/antagonists & inhibitors , Administration, Oral , Animals , Cell Line, Tumor , Female , Half-Life , Humans , Mice , Mice, Inbred C57BL , Mice, Nude , Mice, SCID , Morpholines/chemistry , Morpholines/pharmacokinetics , Neoplasms/pathology , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacokinetics , Pyrimidines/chemistry , Pyrimidines/pharmacokinetics , Pyrroles/chemistry , Pyrroles/pharmacokinetics , Rats , Rats, Nude , Receptor, Fibroblast Growth Factor, Type 1/metabolism , Receptor, Fibroblast Growth Factor, Type 2/metabolism , Receptor, Fibroblast Growth Factor, Type 3/metabolism , Xenograft Model Antitumor Assays
9.
J Clin Invest ; 116(1): 115-24, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16341265

ABSTRACT

The C-C motif chemokine receptor-2 (CCR2) regulates monocyte and macrophage recruitment and is necessary for macrophage-dependent inflammatory responses and the development of atherosclerosis. Although adipose tissue expression and circulating concentrations of CCL2 (also known as MCP1), a high-affinity ligand for CCR2, are elevated in obesity, the role of CCR2 in metabolic disorders, including insulin resistance, hepatic steatosis, and inflammation associated with obesity, has not been studied. To determine what role CCR2 plays in the development of metabolic phenotypes, we studied the effects of Ccr2 genotype on the development of obesity and its associated phenotypes. Genetic deficiency in Ccr2 reduced food intake and attenuated the development of obesity in mice fed a high-fat diet. In obese mice matched for adiposity, Ccr2 deficiency reduced macrophage content and the inflammatory profile of adipose tissue, increased adiponectin expression, ameliorated hepatic steatosis, and improved systemic glucose homeostasis and insulin sensitivity. In mice with established obesity, short-term treatment with a pharmacological antagonist of CCR2 lowered macrophage content of adipose tissue and improved insulin sensitivity without significantly altering body mass or improving hepatic steatosis. These data suggest that CCR2 influences the development of obesity and associated adipose tissue inflammation and systemic insulin resistance and plays a role in the maintenance of adipose tissue macrophages and insulin resistance once obesity and its metabolic consequences are established.


Subject(s)
Dietary Fats , Insulin Resistance , Obesity/physiopathology , Receptors, Chemokine/physiology , Adipose Tissue/physiopathology , Animals , Chemokine CCL2/physiology , Crosses, Genetic , Female , Inflammation/physiopathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Receptors, CCR2 , Receptors, Chemokine/deficiency , Receptors, Chemokine/genetics
10.
Clin Cancer Res ; 25(1): 300-311, 2019 01 01.
Article in English | MEDLINE | ID: mdl-30206163

ABSTRACT

PURPOSE: Bromodomain and extraterminal domain (BET) proteins regulate the expression of many cancer-associated genes and pathways; BET inhibitors have demonstrated activity in diverse models of hematologic and solid tumors. We report the preclinical characterization of INCB054329, a structurally distinct BET inhibitor that has been investigated in phase I clinical trials. EXPERIMENTAL DESIGN: We used multiple myeloma models to investigate vulnerabilities created by INCB054329 treatment that could inform rational combinations. RESULTS: In addition to c-MYC, INCB054329 decreased expression of oncogenes FGFR3 and NSD2/MMSET/WHSC1, which are deregulated in t(4;14)-rearranged cell lines. The profound suppression of FGFR3 sensitized the t(4;14)-positive cell line OPM-2 to combined treatment with a fibroblast growth factor receptor inhibitor in vivo. In addition, we show that BET inhibition across multiple myeloma cell lines resulted in suppressed interleukin (IL)-6 Janus kinase-signal transducers and activators of transcription (JAK-STAT) signaling. INCB054329 displaced binding of BRD4 to the promoter of IL6 receptor (IL6R) leading to reduced levels of IL6R and diminished signaling through STAT3. Combination with JAK inhibitors (ruxolitinib or itacitinib) further reduced JAK-STAT signaling and synergized to inhibit myeloma cell growth in vitro and in vivo. This combination potentiated tumor growth inhibition in vivo, even in the MM1.S model of myeloma that is not intrinsically sensitive to JAK inhibition alone. CONCLUSIONS: Preclinical data reveal insights into vulnerabilities created in myeloma cells by BET protein inhibition and potential strategies that can be leveraged in clinical studies to enhance the activity of INCB054329.


Subject(s)
Cell Cycle Proteins/genetics , Multiple Myeloma/drug therapy , Organic Chemicals/pharmacology , Receptors, Interleukin-6/genetics , STAT3 Transcription Factor/genetics , Transcription Factors/genetics , Animals , Cell Cycle Proteins/antagonists & inhibitors , Cell Line, Tumor , Cell Proliferation/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Heterografts , Histone-Lysine N-Methyltransferase/genetics , Humans , Janus Kinases/genetics , Mice , Multiple Myeloma/genetics , Multiple Myeloma/pathology , Protein Binding/drug effects , Proteins/antagonists & inhibitors , Proteins/genetics , Proto-Oncogene Proteins c-myc/genetics , Receptor, Fibroblast Growth Factor, Type 3/genetics , Repressor Proteins/genetics , Signal Transduction/drug effects , Transcription Factors/antagonists & inhibitors
11.
PLoS One ; 13(6): e0199108, 2018.
Article in English | MEDLINE | ID: mdl-29927999

ABSTRACT

The Proviral Integration site of Moloney murine leukemia virus (PIM) serine/threonine protein kinases are overexpressed in many hematologic and solid tumor malignancies and play central roles in intracellular signaling networks important in tumorigenesis, including the Janus kinase-signal transducer and activator of transcription (JAK/STAT) and phosphatidylinositol 3-kinase (PI3K)/AKT pathways. The three PIM kinase isozymes (PIM1, PIM2, and PIM3) share similar downstream substrates with other key oncogenic kinases and have differing but mutually compensatory functions across tumors. This supports the therapeutic potential of pan-PIM kinase inhibitors, especially in combination with other anticancer agents chosen based on their role in overlapping signaling networks. Reported here is a preclinical characterization of INCB053914, a novel, potent, and selective adenosine triphosphate-competitive pan-PIM kinase inhibitor. In vitro, INCB053914 inhibited proliferation and the phosphorylation of downstream substrates in cell lines from multiple hematologic malignancies. Effects were confirmed in primary bone marrow blasts from patients with acute myeloid leukemia treated ex vivo and in blood samples from patients receiving INCB053914 in an ongoing phase 1 dose-escalation study. In vivo, single-agent INCB053914 inhibited Bcl-2-associated death promoter protein phosphorylation and dose-dependently inhibited tumor growth in acute myeloid leukemia and multiple myeloma xenografts. Additive or synergistic inhibition of tumor growth was observed when INCB053914 was combined with selective PI3Kδ inhibition, selective JAK1 or JAK1/2 inhibition, or cytarabine. Based on these data, pan-PIM kinase inhibitors, including INCB053914, may have therapeutic utility in hematologic malignancies when combined with other inhibitors of oncogenic kinases or standard chemotherapeutics.


Subject(s)
Cell Proliferation/drug effects , Hematologic Neoplasms/drug therapy , Protein Kinase Inhibitors/therapeutic use , Proto-Oncogene Proteins c-pim-1/antagonists & inhibitors , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Apoptosis/drug effects , Cell Line, Tumor , Cytarabine/pharmacology , Cytarabine/therapeutic use , Dose-Response Relationship, Drug , Hematologic Neoplasms/metabolism , Hematologic Neoplasms/pathology , Humans , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/metabolism , Leukemia, Myeloid, Acute/pathology , Mice , Phosphorylation/drug effects , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-bcl-2/metabolism , Signal Transduction/drug effects
12.
Cancer Biol Ther ; 5(6): 657-64, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16627989

ABSTRACT

Overexpression and activating mutations of ErbB family members have been implicated in the development and progression of a variety of tumor types. Cleavage of the HER2 receptor by an as yet unidentified ectodomain sheddase has been shown to liberate the HER2 extracellular domain (ECD) leaving a fragment with constitutive kinase activity that can provide ligand-independent growth and survival signals to the cell. This process is clinically relevant since HER2 ECD serum levels in metastatic breast cancer patients are associated with a poorer prognosis. Thus, inhibition of the HER2 sheddase may provide a novel therapeutic approach for breast cancer. We describe the use of transcriptional profiling, pharmacological and in vitro approaches to identify the major source of HER2 sheddase activity. Real-time PCR was used to identify those ADAM family members which were expressed in HER2 shedding cell lines. siRNAs that selectively inhibited ADAM10 expression reduced HER2 shedding. In addition, we profiled over 1000 small molecules for in vitro inhibition of a panel of ADAM and MMP proteins; a positive correlation was observed only between ADAM10 inhibition and reduction of HER2 ECD shedding in a cell based assay. Finally, in vitro studies demonstrate that in combination with low doses of Herceptin, selective ADAM10 inhibitors decrease proliferation in HER2 overexpressing cell lines while inhibitors, that do not inhibit ADAM10, have no impact. These results are consistent with ADAM10 being a major determinant of HER2 shedding, the inhibition of which, may provide a novel therapeutic approach for treating a variety of cancers with active HER2 signaling.


Subject(s)
ADAM Proteins/metabolism , Amyloid Precursor Protein Secretases/metabolism , Breast Neoplasms/genetics , Membrane Proteins/metabolism , Receptor, ErbB-2/metabolism , ADAM10 Protein , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal, Humanized , Antineoplastic Agents/pharmacology , Base Sequence , Breast Neoplasms/enzymology , Breast Neoplasms/pathology , Cell Line, Tumor , Female , Gene Expression Regulation, Neoplastic , Humans , Polymerase Chain Reaction , RNA, Small Interfering/genetics , Trastuzumab
13.
J Med Chem ; 48(21): 6544-8, 2005 Oct 20.
Article in English | MEDLINE | ID: mdl-16220970

ABSTRACT

Structure-based design led to the discovery of novel (S)-isothiazolidinone ((S)-IZD) heterocyclic phosphotyrosine (pTyr) mimetics that when incorporated into dipeptides are exceptionally potent, competitive, and reversible inhibitors of protein tyrosine phosphatase 1B (PTP1B). The crystal structure of PTP1B in complex with our most potent inhibitor 12 revealed that the (S)-IZD heterocycle interacts extensively with the phosphate binding loop precisely as designed in silico. Our data provide strong evidence that the (S)-IZD is the most potent pTyr mimetic reported to date.


Subject(s)
Dipeptides/chemical synthesis , Phosphotyrosine/chemistry , Protein Tyrosine Phosphatases/antagonists & inhibitors , Protein Tyrosine Phosphatases/chemistry , Thiazoles/chemical synthesis , Crystallography, X-Ray , Dipeptides/chemistry , Drug Design , Models, Molecular , Molecular Mimicry , Protein Tyrosine Phosphatase, Non-Receptor Type 1 , Quantitative Structure-Activity Relationship , Stereoisomerism , Thiazoles/chemistry
14.
Endocrinology ; 143(10): 3866-74, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12239098

ABSTRACT

Using microarray technology, we analyzed 12,000 genes for regulation by TNF-alpha and the synthetic glucocorticoid, dexamethasone, in the human lung epithelial cell line, A549. Only one gene was induced by both agents, the cellular inhibitor of apoptosis 2 (c-IAP2), which was induced 17-fold and 5-fold by TNF-alpha at 2 h and 24 h, respectively, and increased 14-fold and 9-fold by dexamethasone at 2 h and 24 h, respectively. The combination of the two agents together led to an additive increase (34-fold) at 2 h and a more than additive effect (36-fold) at 24 h. The human c-IAP2 promoter contains two nuclear factor (NF)-kappaB sites that have been shown to be required for transcriptional activation by TNF-alpha. To test whether glucocorticoids regulate the c-IAP2 gene at the level of the promoter, a reporter vector containing 947 bases upstream of the start site of transcription of the human c-IAP2 promoter was linked to luciferase [IAP(-947-+54)-LUC] and transfected into A549 cells. Dexamethasone and TNF-alpha each induced reporter activity, whereas the combination of the two agents led to greater induction of luciferase than either one alone. Truncation of the promoter region containing a putative glucocorticoid response element (GRE) at -515 [IAP(-395-+54)-LUC] or mutation of the GRE in the context of the natural promoter [IAP(-947-+54mutGRE)-LUC] resulted in a loss of dexamethasone-mediated induction of reporter activity. Although the functional NF-kappaB sites were retained in the truncated and mutant c-IAP2 promoter constructs, dexamethasone did not inhibit the TNF-alpha induction of luciferase activity, indicating that GR repression through the NF-kappaB sites did not occur. Regulation of the c-IAP2 gene is therefore unique, as GR and NF-kappaB signaling pathways are usually mutually antagonistic, not cooperative. Treatment of A549 cells with TNF-alpha and/or dexamethasone had no effect on cell death, but the two agents were able to inhibit interferon-gamma/anti-FAS antibody-mediated apoptosis. In human glioblastoma A172 cells, TNF-alpha and dexamethasone together elicited a greater than additive increase in c-IAP2 mRNA levels and also inhibited anti-FAS antibody-mediated A172 cell apoptosis. In contrast, in human CEM-C7 leukemic T cells, whereas TNF-alpha and dexamethasone treatment also led to an increase in c-IAP2 mRNA, the two agents were able to induce apoptosis on their own. However, TNF-alpha and dexamethasone were also able to blunt anti-FAS-induced apoptosis in the T cells. These data indicate that the induction of the antiapoptotic protein, c-IAP2, by glucocorticoids and TNF-alpha correlates with the ability of these agents to inhibit apoptosis in a variety of cell types.


Subject(s)
Apoptosis/drug effects , Dexamethasone/pharmacology , Gene Expression Regulation/drug effects , Glucocorticoids/pharmacology , Proteins/genetics , Tumor Necrosis Factor-alpha/pharmacology , Cells, Cultured , Drug Synergism , Glioblastoma/metabolism , Glioblastoma/pathology , Glucocorticoids/physiology , Humans , Lung/cytology , Lung/drug effects , Promoter Regions, Genetic/genetics , RNA, Messenger/metabolism , Response Elements/physiology , T-Lymphocytes/physiology
15.
Gene ; 290(1-2): 35-43, 2002 May 15.
Article in English | MEDLINE | ID: mdl-12062799

ABSTRACT

Bile acid biosynthesis is regulated by both feed-forward and feedback mechanisms involving a cascade of nuclear hormone receptors. Feed-forward regulation of the rate limiting enzyme in bile acid biosynthesis is provided by oxysterols through liver-X-receptor alpha (NR1H3), while feedback regulation is provided by bile acids through farnesoid-X-receptor (FXR) (NR1H4). The Syrian golden hamster provides a useful model for studying lipid metabolism. The hamster metabolizes and transports dietary cholesterol in a similar manner to humans, with the resulting lipid profile being more similar to the human profile than that of other rodent models. Cloning of Fxr from Syrian golden hamster revealed four hamster Fxr splice variants that altered the N-terminal activation domain or the hinge region between the DNA and ligand binding domains. Human genomic sequence and data from hamster Fxr were used to identify and clone a novel human FXR isoform resulting from the use of an alternative promoter. RNA expression analysis indicates that the two human FXR isoforms are differentially expressed in developmental and tissue-specific patterns and are likely to provide a mechanism for cell-specific FXR-dependent transcriptional activity.


Subject(s)
Alternative Splicing , DNA-Binding Proteins/genetics , Promoter Regions, Genetic/genetics , Transcription Factors/genetics , Amino Acid Sequence , Animals , Chenodeoxycholic Acid/pharmacology , Codon, Initiator/genetics , Cricetinae , DNA, Complementary/chemistry , DNA, Complementary/genetics , Exons/genetics , Gene Expression , Gene Expression Regulation/drug effects , Genes/genetics , Humans , Mesocricetus , Molecular Sequence Data , Protein Isoforms/genetics , RNA/genetics , RNA/metabolism , Receptors, Cytoplasmic and Nuclear , Sequence Alignment , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Transcription, Genetic , Tumor Cells, Cultured
16.
J Steroid Biochem Mol Biol ; 85(1): 71-9, 2003 May.
Article in English | MEDLINE | ID: mdl-12798359

ABSTRACT

The peroxisome proliferator activated receptor alpha (PPARalpha) plays a key role in regulating fatty acid metabolism by regulating expression of genes involved in fatty acid oxidation. To identify endogenous transcripts that could be used as surrogate markers for on-target activity of PPARalpha agonists, we employed a global profiling approach using DNA microarrays. The HK-2 cell line derived from proximal tubules of the human kidney, showed induction of several genes, including pyruvate dehydrogenase kinase 4 (PDK-4) and adipocyte differentiation related protein (ADRP) by PPARalpha ligands. HK-2 cells express detectable levels of PPARalpha and its dimerization partner the retinoid X receptor (RXRalpha) proteins. Induction of PDK-4 in these cells correlates with induction of PDK-4 in the liver of fat-fed hamsters. The magnitude of fibrate induction of PDK-4 in the liver also mirrors the decrease in serum triglyceride levels. Thus, induction of PDK-4 by PPARalpha agonists in the HK-2 cell model closely correlates with its induction in vivo and may represent an early marker for PPARalpha agonist action.


Subject(s)
Fatty Acids/metabolism , Isoenzymes/biosynthesis , Kidney Tubules, Proximal/physiology , Membrane Proteins/biosynthesis , Protein Kinases/biosynthesis , Receptors, Cytoplasmic and Nuclear/agonists , Transcription Factors/agonists , Animals , Butyrates/pharmacology , Cells, Cultured , Cricetinae , Enzyme Activation , Fenofibrate/pharmacology , Gene Expression Regulation/physiology , Humans , Hypolipidemic Agents/pharmacology , Isoenzymes/genetics , Isoenzymes/metabolism , Kidney Tubules, Proximal/enzymology , Kidney Tubules, Proximal/metabolism , Ligands , Liver/enzymology , Male , Membrane Proteins/genetics , Mesocricetus , Oligonucleotide Array Sequence Analysis , Perilipin-2 , Phenylurea Compounds/pharmacology , Protein Kinases/genetics , Protein Kinases/metabolism , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Receptors, Cytoplasmic and Nuclear/metabolism , Receptors, Cytoplasmic and Nuclear/physiology , Receptors, Retinoic Acid/genetics , Receptors, Retinoic Acid/metabolism , Retinoid X Receptors , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factors/genetics , Transcription Factors/metabolism , Transcription Factors/physiology , Triglycerides/blood
17.
Genet Test Mol Biomarkers ; 17(5): 429-37, 2013 May.
Article in English | MEDLINE | ID: mdl-23537216

ABSTRACT

The substitution of valine with phenylalanine at amino acid 617 of the Janus kinase 2 (JAK2) gene (JAK2 p.V617F) occurs in a high proportion of patients with myeloproliferative neoplasms (MPNs). The ability to accurately measure JAK2 p.V617F allele burden is of great interest given the diagnostic relevance of the mutation and the ongoing clinical evaluation of JAK inhibitors. A main hurdle in developing quantitative assays for allele burden measurement is the unavailability of accurate standards for both assay validation and use in a standard curve for quantification. We describe our approach to the validation of standards for quantitative assessment of JAK2 p.V617F allele burden in clinical MPN samples. These standards were used in two JAK2 p.V617F assays, which were used to support clinical studies of ruxolitinib (Jakafi(®)) in myelofibrosis, a real-time polymerase chain reaction assay for initial screening of all samples, and a novel single-nucleotide polymorphism typing (SNaPshot)-based assay for samples with less than 5% mutant allele burden. Comparisons of allele burden data from clinical samples generated with these assays show a high degree of concordance with each other and with a pyrosequencing-based assay used for clinical reporting from an independent laboratory, thus providing independent validation to the accuracy of these standards.


Subject(s)
Alleles , Bone Marrow Neoplasms/genetics , Janus Kinase 2/genetics , Myeloproliferative Disorders/genetics , Polymerase Chain Reaction/standards , Polymorphism, Single Nucleotide/genetics , Real-Time Polymerase Chain Reaction/standards , Bone Marrow Neoplasms/diagnosis , Cell Line, Tumor , Humans , Mutation , Myeloproliferative Disorders/diagnosis , Polymerase Chain Reaction/methods , Reproducibility of Results
18.
Diabetes Care ; 33(7): 1516-22, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20413513

ABSTRACT

OBJECTIVE: 11-Beta-hydroxysteroid dehydrogenase type 1 (11betaHSD1) converts inactive cortisone into active cortisol, thereby amplifying intracellular glucocorticoid action. The efficacy and safety of the 11betaHSD1 inhibitor INCB13739 were assessed when added to ongoing metformin monotherapy in patients with type 2 diabetes exhibiting inadequate glycemic control (A1C 7-11%). RESEARCH DESIGN AND METHODS: This double-blind placebo-controlled paralleled study randomized 302 patients with type 2 diabetes (mean A1C 8.3%) on metformin monotherapy (mean 1.5 g/day) to receive one of five INCB13739 doses or placebo once daily for 12 weeks. The primary end point was the change in A1C at study end. Other end points included changes in fasting glucose, lipids, weight, adverse events, and safety. RESULTS: After 12 weeks, 200 mg of INCB13739 resulted in significant reductions in A1C (-0.6%), fasting plasma glucose (-24 mg/dl), and homeostasis model assessment-insulin resistance (HOMA-IR) (-24%) compared with placebo. Total cholesterol, LDL cholesterol, and triglycerides were all significantly decreased in hyperlipidemic patients. Body weight decreased relative to placebo after INCB13739 therapy. A reversible dose-dependent elevation in adrenocorticotrophic hormone, generally within the normal reference range, was observed. Basal cortisol homeostasis, testosterone in men, and free androgen index in women were unchanged by INCB13739. Adverse events were similar across all treatment groups. CONCLUSIONS: INCB13739 added to ongoing metformin therapy was efficacious and well tolerated in patients with type 2 diabetes who had inadequate glycemic control with metformin alone. 11BetaHSD1 inhibition offers a new potential approach to control glucose and cardiovascular risk factors in type 2 diabetes.


Subject(s)
11-beta-Hydroxysteroid Dehydrogenase Type 1/antagonists & inhibitors , Diabetes Mellitus, Type 2/drug therapy , Enzyme Inhibitors/administration & dosage , Hyperglycemia/drug therapy , Metformin/administration & dosage , Sulfonamides/administration & dosage , Administration, Oral , Adolescent , Adult , Aged , Dose-Response Relationship, Drug , Drug Therapy, Combination , Enzyme Inhibitors/adverse effects , Humans , Hypoglycemic Agents/administration & dosage , Middle Aged , Placebos , Sulfonamides/adverse effects , Treatment Outcome , Young Adult
20.
J Immunol ; 175(8): 5370-8, 2005 Oct 15.
Article in English | MEDLINE | ID: mdl-16210643

ABSTRACT

This report describes the characterization of INCB3344, a novel, potent and selective small molecule antagonist of the mouse CCR2 receptor. The lack of rodent cross-reactivity inherent in the small molecule CCR2 antagonists discovered to date has precluded pharmacological studies of antagonists of this receptor and its therapeutic relevance. In vitro, INCB3344 inhibits the binding of CCL2 to mouse monocytes with nanomolar potency (IC(50) = 10 nM) and displays dose-dependent inhibition of CCL2-mediated functional responses such as ERK phosphorylation and chemotaxis with similar potency. Against a panel of G protein-coupled receptors that includes other CC chemokine receptors, INCB3344 is at least 100-fold selective for CCR2. INCB3344 possesses good oral bioavailability and systemic exposure in rodents that allows in vivo pharmacological studies. INCB3344 treatment results in a dose-dependent inhibition of macrophage influx in a mouse model of delayed-type hypersensitivity. The histopathological analysis of tissues from the delayed-type hypersensitivity model demonstrates that inhibition of CCR2 leads to a substantial reduction in tissue inflammation, suggesting that macrophages play an orchestrating role in immune-based inflammatory reactions. These results led to the investigation of INCB3344 in inflammatory disease models. We demonstrate that therapeutic dosing of INCB3344 significantly reduces disease in mice subjected to experimental autoimmune encephalomyelitis, a model of multiple sclerosis, as well as a rat model of inflammatory arthritis. In summary, we present the first report on the pharmacological characterization of a selective, potent and rodent-active small molecule CCR2 antagonist. These data support targeting this receptor for the treatment of chronic inflammatory diseases.


Subject(s)
Pyrrolidines/pharmacology , Receptors, Chemokine/antagonists & inhibitors , Animals , Arthritis, Experimental/drug therapy , Cell Line , Chemotaxis, Leukocyte/drug effects , Chemotaxis, Leukocyte/immunology , Encephalomyelitis, Autoimmune, Experimental/drug therapy , Encephalomyelitis, Autoimmune, Experimental/prevention & control , Female , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Monocytes/drug effects , Protein Binding/drug effects , Protein Binding/immunology , Pyrrolidines/pharmacokinetics , Rats , Rats, Inbred Lew , Receptors, CCR2 , Receptors, Chemokine/deficiency , Receptors, Chemokine/genetics , Structure-Activity Relationship
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