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John BA, Sloan DJ, Jensen TC, Ramaiahgari SC, End P, Resh GE, McClelland RE. A Unidirectional 96-Well Fluidic Culture Platform for Upstream Cell Dosing with Subsequent Downstream Nonlinear and Ascending Exposure Gradients for Real-Time and Cell-Based Toxicity Screening Environments. Appl In Vitro Toxicol 2021; 7:175-191. [PMID: 35028338 PMCID: PMC8743950 DOI: 10.1089/aivt.2021.0006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Introduction: Because of the importance to create in vitro screening tools that better mimic in vivo models, for exposure responses to drugs or toxicants, reproducible and adaptable culture platforms must evolve as approaches to replicate functions that are native to human organ systems. The Stairstep Waterfall (SsWaterfall) Fluidic Culture System is a unidirectional, multiwell, gravity-driven, cell culture system with micro-channels connecting 12 wells in each row (8-row replicates). Materials and Methods: The construct allows for the one-way flow of medium, parent and metabolite compounds, and the cellular signaling between connected culture wells while simultaneously operating as a cascading flow and discretized nonlinear dosing device. Initial cell seeding in SsWaterfall mimics traditional static plate protocols but thereafter functions with controlled flow and ramping concentration versus time exposure environments. Results: To investigate the utility of a microfluidic system for predicting drug efficacy and toxicity, we first delineate device design, fabrication, and characterization of a disposable dosing and gradient-exposure platform. We start with detailed characterizations by demarcating various features of the device, including low nonspecific binding, wettability, biocompatibility with multiple cell types, intra-well and inter-well flow, and efficient auto-mixing properties of dose compounds added into the platform. Discussion: We demonstrate the device utility using an example in sequential testing-screening drug toxicity and efficacy across wide-ranging inducible exposures, 0 → IC100, featuring real-time assessments. Conclusion: The integrated auto-gradient technology, gravity flow with stairstep pathways, offers end-users an easy and quick alternative to evaluate broad-ranging toxicity of new compound entities (e.g., pharmaceutical, environmental, agricultural, cosmetic) as opposed to traditional/arduous manual drug dilutions and/or expensive robotic technology.
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Affiliation(s)
- Bincy A. John
- SciKon Innovation, Inc., Chapel Hill, North Carolina, USA
| | - David J. Sloan
- SciKon Innovation, Inc., Chapel Hill, North Carolina, USA
| | | | - Sreenivasa C. Ramaiahgari
- National Toxicology Program Division, National Institute of Environmental Health Sciences, Durham, North Carolina, USA
| | | | | | - Randall E. McClelland
- SciKon Innovation, Inc., Chapel Hill, North Carolina, USA
- Azture, Inc., La Jolla, California, USA
- Address correspondence to: Dr. Randall E. McClelland, Azture, Inc., PO Box 1759, La Jolla, CA 92038, USA
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Kaul M, End P, Cabanski M, Schuhler C, Jakab A, Kistowska M, Kinhikar A, Maiolica A, Sinn A, Fuhr R, Cenni B. Remibrutinib (LOU064): A selective potent oral BTK inhibitor with promising clinical safety and pharmacodynamics in a randomized phase I trial. Clin Transl Sci 2021; 14:1756-1768. [PMID: 33834628 PMCID: PMC8504815 DOI: 10.1111/cts.13005] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 01/14/2021] [Accepted: 01/19/2021] [Indexed: 02/06/2023] Open
Abstract
Safe and effective new oral therapies for autoimmune, allergic, and inflammatory conditions remain a significant therapeutic need. Here, we investigate the human pharmacokinetics, pharmacodynamics (PDs), and safety of the selective, covalent Bruton's tyrosine kinase (BTK) inhibitor, remibrutinib. Study objectives were explored in randomized single and multiple ascending dose (SAD and MAD, respectively) cohorts with daily doses up to 600 mg, and a crossover food effect (FE) cohort, in adult healthy subjects without (SAD [n =80]/FE [n =12]) or with asymptomatic atopic diathesis (MAD [n =64]). A single oral dose of remibrutinib (0.5-600 mg) was rapidly absorbed (time to maximum concentration = 0.5 h-1.25 h) with an apparent blood clearance of 280-560 L/h and apparent volume of distribution of 400-15,000 L. With multiple doses (q.d. and b.i.d.), no pronounced accumulation of remibrutinib was detected (mean residence time was <3 h). Food intake showed no clinically relevant effect on remibrutinib exposure suggesting no need for dose adaptation. With remibrutinib doses greater than or equal to 30 mg, blood BTK occupancy was greater than 95% for at least 24 h (SAD). With MAD, remibrutinib reached near complete blood BTK occupancy at day 12 predose with greater than or equal to 10 mg q.d. Near complete basophil or skin prick test (SPT) inhibition at day 12 predose was achieved at greater than or equal to 50 mg q.d. for CD63 and at greater than or equal to 100 mg q.d. for SPT. Remibrutinib was well-tolerated at all doses without any dose-limiting toxicity. Remibrutinib showed encouraging blood and skin PDs with a favorable safety profile, supporting further development for diseases driven by mast cells, basophils, and B-cells, such as chronic spontaneous urticaria, allergic asthma, or Sjögren's syndrome.
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Affiliation(s)
- Martin Kaul
- Novartis Institutes for Biomedical ResearchBaselSwitzerland
| | - Peter End
- Novartis Institutes for Biomedical ResearchBaselSwitzerland
| | | | | | | | | | - Arvind Kinhikar
- Novartis Institutes for Biomedical ResearchCambridgeMassachusettsUSA
| | | | - Angela Sinn
- Early Phase Clinical UnitParexel InternationalBerlinGermany
| | - Rainard Fuhr
- Early Phase Clinical UnitParexel InternationalBerlinGermany
| | - Bruno Cenni
- Novartis Institutes for Biomedical ResearchBaselSwitzerland
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Huth F, Schiller H, Jin Y, Poller B, Schuhler C, Weis W, Woessner R, Drollmann A, End P. Novel Bruton's Tyrosine Kinase inhibitor remibrutinib: Drug-drug interaction potential as a victim of CYP3A4 inhibitors based on clinical data and PBPK modeling. Clin Transl Sci 2021; 15:118-129. [PMID: 34432364 PMCID: PMC8742645 DOI: 10.1111/cts.13126] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 06/30/2021] [Accepted: 07/14/2021] [Indexed: 12/13/2022] Open
Abstract
Remibrutinib, a novel oral Bruton’s Tyrosine Kinase inhibitor (BTKi) is highly selective for BTK, potentially mitigating the side effects of other BTKis. Enzyme phenotyping identified CYP3A4 to be the predominant elimination pathway of remibrutinib. The impact of concomitant treatment with CYP3A4 inhibitors, grapefruit juice and ritonavir (RTV), was investigated in this study in combination with an intravenous microtracer approach. Pharmacokinetic (PK) parameters, including the fraction absorbed, the fractions escaping intestinal and hepatic first‐pass metabolism, the absolute bioavailability, systemic clearance, volume of distribution at steady‐state, and the fraction metabolized via CYP3A4 were evaluated. Oral remibrutinib exposure increased in the presence of RTV 4.27‐fold, suggesting that remibrutinib is not a sensitive CYP3A4 substrate. The rich PK dataset supported the building of a robust physiologically‐based pharmacokinetic (PBPK) model, which well‐described the therapeutic dose range of 25–100 mg. Simulations of untested scenarios revealed an absence of drug‐drug interaction (DDI) risk between remibrutinib and the weak CYP3A4 inhibitor fluvoxamine (area under the concentration‐time curve ratio [AUCR] <1.25), and a moderate effect with the CYP3A4 inhibitor erythromycin (AUCR: 2.71). Predictions with the moderate and strong CYP3A4 inducers efavirenz and rifampicin, suggested a distinct remibrutinib exposure decrease of 64% and 89%. Oral bioavailability of remibrutinib was 34%. The inclusion of an intravenous microtracer allowed the determination of all relevant remibrutinib PK parameters, which facilitated construction of the PBPK model. This will provide guidance on the selection or restriction of comedications and prediction of DDI risks.
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Affiliation(s)
- Felix Huth
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Hilmar Schiller
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Yi Jin
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Birk Poller
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | | | | | - Ralph Woessner
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Anton Drollmann
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Peter End
- Novartis Institutes for BioMedical Research, Basel, Switzerland
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4
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Kaul M, Storim J, End P, Cabanski M, Jakab A, Schuhler C, Funhoff E, Shaefer F, Dimanova E, Kistowska M, Kinhikar A, Maiolica A, Sinn A, Fuhr R, Cenni B. LOU064 : un inhibiteur covalent oral de la BTK hautement sélectif et puissant avec des effets pharmacodynamiques prometteurs au niveau de la peau. Ann Dermatol Venereol 2020. [DOI: 10.1016/j.annder.2020.09.536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Drug-induced liver injury (DILI) remains one of the key challenges in drug development due to the mechanisms of action being multifactorial in nature. This is particularly the case for idiosyncratic DILI which occurs in a very low frequency in humans (e.g., 1:10,000). Despite perceptions that acyl glucuronide metabolites are defacto risks for DILI, scientific evidence suggests that acyl glucuronide formation alone does not pose an increased risk compared to other drug metabolites. This applies in particular to those acyl glucuronides which are not reactive and do not form covalent adducts with proteins. The goal of this paper is to provide guidance on preclinical and clinical strategies to evaluate the potential for acyl glucuronide formation to contribute to DILI. A key element of our proposed safety assessment is to investigate whether a particular acyl glucuronide is reactive or not and whether systemic exposure in humans can be demonstrated in animal toxicology studies following administration of the parent drug. While standard animal toxicology studies can identify overtly hepatotoxic compounds, these studies are not predictive for drugs that produce idiosyncratic forms of DILI. In addition, we do not recommend conducting toxicology studies of administered individual acyl glucuronides due to differences in pharmacokinetic and dispositional properties from the endogenously produced metabolites. Once a drug candidate has entered clinical trials, the focus should be on clinical safety data and emerging risk-benefit analysis.
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Affiliation(s)
- Markus Walles
- PK Sciences, Novartis Institutes for Biomedical Research, Novartis Campus, 4052 Basel, Switzerland
| | - Alan P Brown
- Preclinical Safety, Novartis Institutes for Biomedical Research, 220 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Alfred Zimmerlin
- PK Sciences, Novartis Institutes for Biomedical Research, Novartis Campus, 4052 Basel, Switzerland
| | - Peter End
- PK Sciences, Novartis Institutes for Biomedical Research, Novartis Campus, 4052 Basel, Switzerland
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Webb N, Haraldsson B, Schubart A, Milojevic J, End P, Holbro T, Junge G. MO042LNP023: A NOVEL ORAL COMPLEMENT ALTERNATIVE PATHWAY FACTOR B INHIBITOR FOR THE TREATMENT OF GLOMERULAR DISEASE. Nephrol Dial Transplant 2020. [DOI: 10.1093/ndt/gfaa140.mo042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background and Aims
The alternative complement pathway (AP) provides the central amplification loop of complement activation and is critically involved in a number of diseases including C3 glomerulopathy (C3G), paroxysmal nocturnal haemoglobinuria (PNH) and atypical haemolytic uremic syndrome. There is also evidence for AP dysregulation in IgA and membranous nephropathies (IgAN, MN). Novartis has developed a highly selective oral low molecular weight inhibitor of complement Factor B, a key AP protease. LNP023 potently blocks AP activation in vitro and in vivo and is efficacious in passive Heymann nephritis in rats, suggesting an important role of the AP in classical-pathway mediated nephropathies.
Method
LNP023 was tested at increasing single or multiple ascending doses in a Phase I safety, tolerability, pharmacokinetic (PK) and pharmacodynamic study in healthy volunteers. Complement inhibition was measured by the ex vivo Wieslab assay and by quantifying fragment Bb level.
Results
LNP023 was well tolerated at all doses from 5 mg to 400 mg (single dose) and from 25 mg to 200 mg bid for 14 days (multiple dose). There were no deaths, SAEs or AEs leading to study drug discontinuation in LNP023-treated subjects. LNP023 dose-dependently inhibited the AP complement system. Based on the Wieslab assay, maximal inhibition of AP activity (80% or more) was observed 2 hours after a single dose of 10 mg or higher. The level of Bb decreased until 12 hours post-dose. Approximately 30% to 50% decrease in Bb, relative to baseline, was achieved for subjects receiving a single dose of LNP023 of 5mg or higher. For both assays, the duration of this inhibition was dependent upon the dose administered. Persistent inhibition was obtained in the multiple dose cohorts, the magnitude of inhibition being dose-dependent for the Wieslab assay but not for Bb. PK studies showed rapid drug absorption and no evidence of food effect. The plasma clearance was moderate and the terminal half-life was around 20h. There was an under-proportional dose-exposure relationship. Among other mechanisms, binding to highly expressed target (Factor B) is believed to affect clearance and thus exposure.
Following a successful proof of concept Phase 2 study in PNH (data not shown), LNP023 is currently being investigated in three ongoing Phase 2 studies in IgAN (NCT03373461), C3G (NCT03832114) and MN (NCT04154787). The IgAN study has an adaptive seamless design; the first part has recently completed, 46 patients having received 3 months of one of three LNP023 doses or placebo. The study remains blinded; however, similar to the FIH study safety appears excellent, with only one treatment-emergent SAE (inhalation of chlorine gas) and two SAEs in the post-treatment follow-up period. No patient discontinued randomised treatment for any reason. There were no episodes of proven infection with encapsulated bacteria. The independent data safety monitoring committee have endorsed the study proceeding to the second part with the addition of a fourth LNP023 dose and recruitment is ongoing, completion being anticipated in mid-2020.
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Affiliation(s)
| | | | | | | | - Peter End
- Novartis Pharma AG, Basel, Switzerland
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Poller B, Woessner R, Barve A, Tillmann HC, Vemula J, Nica A, Elbast W, Schiller H, End P, Camenisch G, Weiss M. Fevipiprant has a low risk of influencing co-medication pharmacokinetics: Impact on simvastatin and rosuvastatin in different SLCO1B1 genotypes. Pulm Pharmacol Ther 2019; 57:101809. [PMID: 31195091 DOI: 10.1016/j.pupt.2019.101809] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 04/23/2019] [Accepted: 05/27/2019] [Indexed: 12/31/2022]
Abstract
Fevipiprant, a prostaglandin D2 receptor 2 antagonist, is in clinical development as a treatment for asthma. The goal of this study was to assess the potential of fevipiprant to cause drug-drug interactions (DDI) as a perpetrator, that is, by altering the pharmacokinetics (PK) of co-medications. In vitro drug interaction studies of clinically relevant drug metabolizing enzymes and transporters were conducted for fevipiprant and its acyl glucuronide (AG) metabolite. Comparison of Ki values with unbound systemic or portal vein steady-state plasma exposure of fevipiprant and its AG metabolite revealed the potential for inhibition of organic anion transporting polypeptide 1B1 (OATP1B1) transporters (R-value of 5.99), while other targets including cytochrome P450 enzymes were not, or only marginally, inhibited. Consequently, an open-label, two-part, two-period, single-sequence clinical study assessed the effect of fevipiprant 450 mg QD on the pharmacokinetics of simvastatin 20 mg and rosuvastatin 20 mg, two statins with different dependency in OATP1B1-mediated hepatic uptake, in healthy adult volunteers. The study also assessed the pharmacogenetics of the SLCO1B1 gene, which encodes OATP1B1. Clinically, fevipiprant 450 mg QD showed a low potential for interaction and increased the peak concentrations of simvastatin acid and rosuvastatin by 2.23- and 1.87-fold, respectively, with little or no impact on total exposure. Genotype analysis confirmed that SLCO1B1 genotype influences statin pharmacokinetics to a similar extent either with or without fevipiprant co-administration. In summary, fevipiprant at 450 mg QD has only minor liabilities as a perpetrator for DDI.
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Affiliation(s)
- Birk Poller
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Ralph Woessner
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Avantika Barve
- Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA
| | | | | | - Alexandra Nica
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Walid Elbast
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Hilmar Schiller
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Peter End
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Gian Camenisch
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Markus Weiss
- Novartis Institutes for Biomedical Research, Basel, Switzerland.
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8
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Kullak-Ublick GA, Andrade RJ, Merz M, End P, Benesic A, Gerbes AL, Aithal GP. Drug-induced liver injury: recent advances in diagnosis and risk assessment. Gut 2017; 66:1154-1164. [PMID: 28341748 PMCID: PMC5532458 DOI: 10.1136/gutjnl-2016-313369] [Citation(s) in RCA: 299] [Impact Index Per Article: 42.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 02/24/2017] [Accepted: 02/28/2017] [Indexed: 12/12/2022]
Abstract
Idiosyncratic drug-induced liver injury (IDILI) is a rare but potentially severe adverse drug reaction that should be considered in patients who develop laboratory criteria for liver injury secondary to the administration of a potentially hepatotoxic drug. Although currently used liver parameters are sensitive in detecting DILI, they are neither specific nor able to predict the patient's subsequent clinical course. Genetic risk assessment is useful mainly due to its high negative predictive value, with several human leucocyte antigen alleles being associated with DILI. New emerging biomarkers which could be useful in assessing DILI include total keratin18 (K18) and caspase-cleaved keratin18 (ccK18), macrophage colony-stimulating factor receptor 1, high mobility group box 1 and microRNA-122. From the numerous in vitro test systems that are available, monocyte-derived hepatocytes generated from patients with DILI show promise in identifying the DILI-causing agent from among a panel of coprescribed drugs. Several computer-based algorithms are available that rely on cumulative scores of known risk factors such as the administered dose or potential liabilities such as mitochondrial toxicity, inhibition of the bile salt export pump or the formation of reactive metabolites. A novel DILI cluster score is being developed which predicts DILI from multiple complimentary cluster and classification models using absorption-distribution-metabolism-elimination-related as well as physicochemical properties, diverse substructural descriptors and known structural liabilities. The provision of more advanced scientific and regulatory guidance for liver safety assessment will depend on validating the new diagnostic markers in the ongoing DILI registries, biobanks and public-private partnerships.
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Affiliation(s)
- Gerd A Kullak-Ublick
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich and University of Zurich, Zurich, Switzerland,Drug Safety and Epidemiology, Novartis Pharma, Basel, Switzerland
| | - Raul J Andrade
- Unidad de Gestión Clínica de Aparato Digestivo, Instituto de Investigación Biomédica de Málaga-IBIMA, Hospital Universitario Virgen de la Victoria, Universidad de Málaga, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Málaga, Spain
| | - Michael Merz
- Novartis Institutes for BioMedical Research, Novartis Campus, Basel, Switzerland
| | - Peter End
- Novartis Institutes for BioMedical Research, Novartis Campus, Basel, Switzerland
| | - Andreas Benesic
- Department of Medicine II, Klinikum Grosshadern of the University of Munich (KUM), University of Munich, Munich, Germany,MetaHeps GmbH, Planegg/Martinsried, Germany
| | - Alexander L Gerbes
- Department of Medicine II, Klinikum Grosshadern of the University of Munich (KUM), University of Munich, Munich, Germany
| | - Guruprasad P Aithal
- National Institute for Health Research (NIHR), Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham, UK
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Pearson D, Weiss HM, Jin Y, Jaap van Lier J, Erpenbeck VJ, Glaenzel U, End P, Woessner R, Eggimann F, Camenisch G. Absorption, Distribution, Metabolism, and Excretion of the Oral Prostaglandin D2 Receptor 2 Antagonist Fevipiprant (QAW039) in Healthy Volunteers and In Vitro. Drug Metab Dispos 2017; 45:817-825. [PMID: 28442499 DOI: 10.1124/dmd.117.075358] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 04/20/2017] [Indexed: 11/22/2022] Open
Abstract
Fevipiprant is a novel oral prostaglandin D2 receptor 2 (DP2; also known as CRTh2) antagonist, which is currently in development for the treatment of severe asthma and atopic dermatitis. We investigated the absorption, distribution, metabolism, and excretion properties of fevipiprant in healthy subjects after a single 200-mg oral dose of [14C]-radiolabeled fevipiprant. Fevipiprant and metabolites were analyzed by liquid chromatography coupled to tandem mass spectrometry and radioactivity measurements, and mechanistic in vitro studies were performed to investigate clearance pathways and covalent plasma protein binding. Biotransformation of fevipiprant involved predominantly an inactive acyl glucuronide (AG) metabolite, which was detected in plasma and excreta, representing 28% of excreted drug-related material. The AG metabolite was found to covalently bind to human plasma proteins, likely albumin; however, in vitro covalent binding to liver protein was negligible. Excretion was predominantly as unchanged fevipiprant in urine and feces, indicating clearance by renal and possibly biliary excretion. Fevipiprant was found to be a substrate of transporters organic anion transporter 3 (OAT3; renal uptake), multidrug resistance gene 1 (MDR1; possible biliary excretion), and organic anion-transporting polypeptide 1B3 (OATP1B3; hepatic uptake). Elimination of fevipiprant occurs via glucuronidation by several uridine 5'-diphospho glucuronosyltransferase (UGT) enzymes as well as direct excretion. These parallel elimination pathways result in a low risk of major drug-drug interactions or pharmacogenetic/ethnic variability for this compound.
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Affiliation(s)
- David Pearson
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
| | - H Markus Weiss
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
| | - Yi Jin
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
| | - Jan Jaap van Lier
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
| | - Veit J Erpenbeck
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
| | - Ulrike Glaenzel
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
| | - Peter End
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
| | - Ralph Woessner
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
| | - Fabian Eggimann
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
| | - Gian Camenisch
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, Switzerland (D.P., H.M.W., Y.J., V.J.E., U.G., P.E., R.W., F.E., G.C.); PRA International, Early Development Services, Zuidlaren, the Netherlands (J.J.v.L.)
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10
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Reilly J, Williams SL, Forster CJ, Kansara V, End P, Serrano-Wu MH. High-Throughput Melanin-Binding Affinity and In Silico Methods to Aid in the Prediction of Drug Exposure in Ocular Tissue. J Pharm Sci 2015; 104:3997-4001. [PMID: 26524700 DOI: 10.1002/jps.24680] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 09/02/2015] [Accepted: 09/17/2015] [Indexed: 11/11/2022]
Abstract
Drugs possessing the ability to bind to melanin-rich tissue, such as the eye, are linked with higher ocular exposure, and therefore have the potential to affect the efficacy and safety profiles of therapeutics. A high-throughput melanin chromatographic affinity assay has been developed and validated, which has allowed the rapid melanin affinity assessment for a large number of compounds. Melanin affinity of compounds can be quickly assigned as low, medium, or high melanin binders. A high-throughput chromatographic method has been developed and fully validated to assess melanin affinity of pharmaceuticals and has been useful in predicting ocular tissue distribution in vivo studies. The high-throughput experimental approach has also allowed for a specific training set of 263 molecules for a quantitative structure-affinity relationships (QSAR) method to be developed, which has also been shown to be a predictor of ocular tissue exposure. Previous studies have reported the development of in silico QSAR models based on training sets of relatively small and mostly similar compounds; this model covers a broader range of melanin-binding affinities than what has been previously published and identified several physiochemical descriptors to be considered in the design of compounds where melanin-binding modulation is desired.
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Affiliation(s)
- John Reilly
- Novartis Institutes for BioMedical Research, Global Discovery Chemistry, Cambridge, Massachusetts 02139.
| | - Sarah L Williams
- Novartis Institutes for BioMedical Research, Global Discovery Chemistry, Cambridge, Massachusetts 02139
| | - Cornelia J Forster
- Novartis Institutes for BioMedical Research, Global Discovery Chemistry, Cambridge, Massachusetts 02139
| | - Viral Kansara
- Novartis Institutes for BioMedical Research, Ophthalmology, Cambridge, Massachusetts 02139
| | - Peter End
- Novartis Institutes for BioMedical Research, DMPK, Basel, Switzerland
| | - Michael H Serrano-Wu
- Novartis Institutes for BioMedical Research, Global Discovery Chemistry, Cambridge, Massachusetts 02139
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Pan S, Gray NS, Gao W, Mi Y, Fan Y, Wang X, Tuntland T, Che J, Lefebvre S, Chen Y, Chu A, Hinterding K, Gardin A, End P, Heining P, Bruns C, Cooke NG, Nuesslein-Hildesheim B. Discovery of BAF312 (Siponimod), a Potent and Selective S1P Receptor Modulator. ACS Med Chem Lett 2013; 4:333-7. [PMID: 24900670 DOI: 10.1021/ml300396r] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 01/04/2013] [Indexed: 12/17/2022] Open
Abstract
A novel series of alkoxyimino derivatives as S1P1 agonists were discovered through de novo design using FTY720 as the chemical starting point. Extensive structure-activity relationship studies led to the discovery of (E)-1-(4-(1-(((4-cyclohexyl-3-(trifluoromethyl)benzyl)oxy)imino)ethyl)-2-ethylbenzyl)azetidine-3-carboxylic acid (32, BAF312, Siponimod), which has recently completed phase 2 clinical trials in patients with relapsing-remitting multiple sclerosis.
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Affiliation(s)
- Shifeng Pan
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Nathanael S. Gray
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Wenqi Gao
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Yuan Mi
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Yi Fan
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Xing Wang
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Tove Tuntland
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Jianwei Che
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Sophie Lefebvre
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Yu Chen
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Alan Chu
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United
States
| | - Klaus Hinterding
- Novartis Institute for Biomedical Research, Novartis Campus,
CH-4056 Basel, Switzerland
| | - Anne Gardin
- Novartis Institute for Biomedical Research, Novartis Campus,
CH-4056 Basel, Switzerland
| | - Peter End
- Novartis Institute for Biomedical Research, Novartis Campus,
CH-4056 Basel, Switzerland
| | - Peter Heining
- Novartis Institute for Biomedical Research, Novartis Campus,
CH-4056 Basel, Switzerland
| | - Christian Bruns
- Novartis Institute for Biomedical Research, Novartis Campus,
CH-4056 Basel, Switzerland
| | - Nigel G. Cooke
- Novartis Institute for Biomedical Research, Novartis Campus,
CH-4056 Basel, Switzerland
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12
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Dieterle F, Perentes E, Cordier A, Roth DR, Verdes P, Grenet O, Pantano S, Moulin P, Wahl D, Mahl A, End P, Staedtler F, Legay F, Carl K, Laurie D, Chibout SD, Vonderscher J, Maurer G. Urinary clusterin, cystatin C, beta2-microglobulin and total protein as markers to detect drug-induced kidney injury. Nat Biotechnol 2010; 28:463-9. [PMID: 20458316 DOI: 10.1038/nbt.1622] [Citation(s) in RCA: 238] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Accepted: 03/22/2010] [Indexed: 01/28/2023]
Abstract
Earlier and more reliable detection of drug-induced kidney injury would improve clinical care and help to streamline drug-development. As the current standards to monitor renal function, such as blood urea nitrogen (BUN) or serum creatinine (SCr), are late indicators of kidney injury, we conducted ten nonclinical studies to rigorously assess the potential of four previously described nephrotoxicity markers to detect drug-induced kidney and liver injury. Whereas urinary clusterin outperformed BUN and SCr for detecting proximal tubular injury, urinary total protein, cystatin C and beta2-microglobulin showed a better diagnostic performance than BUN and SCr for detecting glomerular injury. Gene and protein expression analysis, in-situ hybridization and immunohistochemistry provide mechanistic evidence to support the use of these four markers for detecting kidney injury to guide regulatory decision making in drug development. The recognition of the qualification of these biomarkers by the EMEA and FDA will significantly enhance renal safety monitoring.
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Affiliation(s)
- Frank Dieterle
- Novartis Institutes for BioMedical Research, Novartis, Basel, Switzerland.
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13
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Waldmeier F, Glaenzel U, Wirz B, Oberer L, Schmid D, Seiberling M, Valencia J, Riviere GJ, End P, Vaidyanathan S. Absorption, Distribution, Metabolism, and Elimination of the Direct Renin Inhibitor Aliskiren in Healthy Volunteers. Drug Metab Dispos 2007; 35:1418-28. [PMID: 17510248 DOI: 10.1124/dmd.106.013797] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Aliskiren (2(S),4(S),5(S),7(S)-N-(2-carbamoyl-2-methylpropyl)-5-amino-4-hydroxy-2,7-diisopropyl-8-[4-methoxy-3-(3-methoxypropoxy)phenyl]-octanamid hemifumarate) is the first in a new class of orally active, nonpeptide direct renin inhibitors developed for the treatment of hypertension. The absorption, distribution, metabolism, and excretion of [(14)C]aliskiren were investigated in four healthy male subjects after administration of a single 300-mg oral dose in an aqueous solution. Plasma radioactivity and aliskiren concentration measurements and complete urine and feces collections were made for 168 h postdose. Peak plasma levels of aliskiren (C(max)) were achieved between 2 and 5 h postdose. Unchanged aliskiren represented the principal circulating species in plasma, accounting for 81% of total plasma radioactivity (AUC(0-infinity)), and indicating very low exposure to metabolites. Terminal half-lives for radioactivity and aliskiren in plasma were 49 h and 44 h, respectively. Dose recovery over 168 h was nearly complete (91.5% of dose); excretion occurred almost completely via the fecal route (90.9%), with only 0.6% recovered in the urine. Unabsorbed drug accounted for a large dose proportion recovered in feces in unchanged form. Based on results from this and from previous studies, the absorbed fraction of aliskiren can be estimated to approximately 5% of dose. The absorbed dose was partly eliminated unchanged via the hepatobiliary route. Oxidized metabolites in excreta accounted for at least 1.3% of the radioactive dose. The major metabolic pathways for aliskiren were O-demethylation at the phenyl-propoxy side chain or 3-methoxy-propoxy group, with further oxidation to the carboxylic acid derivative.
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14
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Affiliation(s)
- G Panayotou
- Ludwig Institute for Cancer Research, 91 Riding House Street, London W1P 8BT, UK
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15
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Panayotou G, Gish G, End P, Truong O, Gout I, Dhand R, Fry MJ, Hiles I, Pawson T, Waterfield MD. Interactions between SH2 domains and tyrosine-phosphorylated platelet-derived growth factor beta-receptor sequences: analysis of kinetic parameters by a novel biosensor-based approach. Mol Cell Biol 1993; 13:3567-76. [PMID: 8388538 PMCID: PMC359826 DOI: 10.1128/mcb.13.6.3567-3576.1993] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The interaction between SH2 domains and phosphotyrosine-containing sequences was examined by real-time measurements of kinetic parameters. The SH2 domains of the p85 subunit of the phosphatidylinositol 3-kinase as well as of other signaling molecules were expressed in bacteria as glutathione S-transferase fusion proteins. Phosphotyrosine-containing peptides, corresponding to two autophosphorylation sites on the human platelet-derived growth factor beta-receptor that are responsible for phosphatidylinositol 3-kinase binding, were synthesized and used as capturing molecules, immobilized on a biosensor surface. The association and dissociation rate constants for binding to both sites were determined for intact p85 and the recombinant SH2 domains. High association rates were found to be coupled to very fast dissociation rates for all interactions studied. A binding specificity was observed for the two SH2 domains of p85, with the N-terminal SH2 binding with high affinity to the Tyr-751 site but not to the Tyr-740 site, and the C-terminal SH2 interacting strongly with both sites. This approach should be generally applicable to the study of the specificity inherent in the assembly of signaling complexes by activated protein-tyrosine kinase receptors.
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Affiliation(s)
- G Panayotou
- Ludwig Institute for Cancer Research, London, United Kingdom
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16
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End P, Gout I, Fry MJ, Panayotou G, Dhand R, Yonezawa K, Kasuga M, Waterfield MD. A biosensor approach to probe the structure and function of the p85 alpha subunit of the phosphatidylinositol 3-kinase complex. J Biol Chem 1993; 268:10066-75. [PMID: 7683666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Phosphatidylinositol 3-kinase, which generates putative novel second messenger phospholipids, is a heterodimer composed of regulatory adaptor 85-kDa and catalytic 110-kDa subunits. The p85 alpha subunit contains a NH2-terminal src homology (SH) 3 domain, a region with homology to the product of the breakpoint cluster region (bcr) gene, and a COOH-terminal portion of the molecule which contains two SH2 domains, separated by a spacer region. In this study a panel of monoclonal antibodies (mAb) was raised against recombinant bovine p85 alpha to probe its multidomain structure in relation to function. These mAbs were characterized using a BIAcore biosensor instrument. Epitopes for nine mAbs were mapped in relation to the domain structure of p85 alpha using recombinant protein fragments expressed in bacteria. These mAbs were then used to map the sites on p85 alpha which are involved in growth factor receptor binding. Two interesting classes of functional mAbs were identified. First, mAb U14, whose epitope lies within the NH2-terminal SH2 domain of p85 alpha, blocked the interaction of p85 alpha with activated protein-tyrosine kinase receptors. Second, real-time binding experiments using phospholipid-containing vesicles showed that p85 alpha by itself could specifically bind certain phospholipids. Two mAbs (U9 and U15) with epitopes located in the inter-SH2 spacer region blocked the binding of lipids to this site. The relevance of these observations to understanding the relationship of structure to function of p85 and the phosphatidylinositol 3-kinase are discussed.
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Affiliation(s)
- P End
- Ludwig Institute for Cancer Research, London, United Kingdom
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17
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End P, Gout I, Fry M, Panayotou G, Dhand R, Yonezawa K, Kasuga M, Waterfield M. A biosensor approach to probe the structure and function of the p85 alpha subunit of the phosphatidylinositol 3-kinase complex. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)82173-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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18
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Ruiz-Larrea F, Vicendo P, Yaish P, End P, Panayotou G, Fry MJ, Morgan SJ, Thompson A, Parker PJ, Waterfield MD. Characterization of the bovine brain cytosolic phosphatidylinositol 3-kinase complex. Biochem J 1993; 290 ( Pt 2):609-16. [PMID: 8383968 PMCID: PMC1132318 DOI: 10.1042/bj2900609] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Receptor-linked phosphatidylinositol (PtdIns) 3-kinase may generate a second-messenger signal. Here a large-scale purification of the bovine brain enzyme, based on methods developed by Morgan, Smith and Parker [(1990) Eur. J. Biochem. 191, 761-767] and Fry, Panayotou, Dhand, Ruiz-Larrea, Gout, Nguyen, Courtneidge and Waterfield [(1992) Biochem. J. 288, 383-393] is described. The purified enzyme is shown to be a heterodimer of 85 kDa and 110 kDa protein subunits (p85 and p110). Labelling with 5'-p-fluorosulphonylbenzoyladenosine shows that p110 contains an ATP-binding site and confers catalytic activity to the complex. The purified complex is known to be highly phosphorylated on both p85 alpha and p110 subunits, and dephosphorylation generates a deactivated complex, indicating that phosphorylation is an important covalent modification of the complex and may modulate PtdIns 3-kinase activity.
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Abstract
The large, multidomain extracellular matrix protein tenascin displays a markedly restricted tissue distribution during embryogenesis and remains present only in a few adult tissues. The protein is reexpressed, however, during wound healing and in the stroma of malignant tumours. While a variety of studies have dealt with the important role of tenascin in the development of neural and non-neural tissues, there is growing evidence that tenascin expression may be associated with proliferation of cells lining these tissues. The presence of repeating domains in tenascin similar to those in epidermal growth factor prompted us to investigate the ability of tenascin to modulate the growth of different cell types. Tenascin was actually found to be mitogenic for several cell types. This mitogenic activity, however, appears to be associated with a region in the fibronectin type III domains. The mitogenic mechanism is clearly distinct from pathways used by peptide growth factors such as epidermal growth factor and platelet-derived growth factor, which activate the intrinsic tyrosine kinase activity of their cell-surface receptors. However, we show that this large extracellular matrix molecule is efficiently internalised and may be processed by responding cells.
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Affiliation(s)
- P End
- Biozentrum, Universität Basel, Switzerland
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20
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McGlade CJ, Ellis C, Reedijk M, Anderson D, Mbamalu G, Reith AD, Panayotou G, End P, Bernstein A, Kazlauskas A. SH2 domains of the p85 alpha subunit of phosphatidylinositol 3-kinase regulate binding to growth factor receptors. Mol Cell Biol 1992; 12:991-7. [PMID: 1372092 PMCID: PMC369531 DOI: 10.1128/mcb.12.3.991-997.1992] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The binding of cytoplasmic signaling proteins such as phospholipase C-gamma 1 and Ras GTPase-activating protein to autophosphorylated growth factor receptors is directed by their noncatalytic Src homology region 2 (SH2) domains. The p85 alpha regulatory subunit of phosphatidylinositol (PI) 3-kinase, which associates with several receptor protein-tyrosine kinases, also contains two SH2 domains. Both p85 alpha SH2 domains, when expressed individually as fusion proteins in bacteria, bound stably to the activated beta receptor for platelet-derived growth factor (PDGF). Complex formation required PDGF stimulation and was dependent on receptor tyrosine kinase activity. The bacterial p85 alpha SH2 domains recognized activated beta PDGF receptor which had been immobilized on a filter, indicating that SH2 domains contact autophosphorylated receptors directly. Several receptor tyrosine kinases within the PDGF receptor subfamily, including the colony-stimulating factor 1 receptor and the Steel factor receptor (Kit), also associate with PI 3-kinase in vivo. Bacterially expressed SH2 domains derived from the p85 alpha subunit of PI 3-kinase bound in vitro to the activated colony-stimulating factor 1 receptor and to Kit. We infer that the SH2 domains of p85 alpha bind to high-affinity sites on these receptors, whose creation is dependent on receptor autophosphorylation. The SH2 domains of p85 are therefore primarily responsible for the binding of PI 3-kinase to activated growth factor receptors.
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Affiliation(s)
- C J McGlade
- Division of Molecular and Developmental Biology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
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21
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Abstract
Laminin and fragments (1, 1-4) containing the inner rod-like segments from its short arms, which consist of cysteine-rich, "EGF-like" repeats, stimulated thymidine incorporation in cultured cells possessing EGF receptors but had no effect on a cell line lacking this receptor. The response was comparable to that of EGF concerning effective concentrations, magnitude, time dependence, and synergistic enhancement by insulin. Other fragments (4 and 8) were inactive. Laminin and its active fragments could not compete with the binding of EGF to cells. There was no correlation between growth promotion and attachment of cells to a high affinity binding site present on laminin fragment 8. The data indicate that mitogenic effects induced by laminin and EGF proceed in some steps via related pathways and that different domains of laminin are involved in growth promotion and in adhesion and spreading of cells.
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Affiliation(s)
- G Panayotou
- National Institute for Medical Research, London, England
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