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Trautmann M, Wendel V, Prinz D, Primmel B, Willging G, Nagorsen E, Suckert A, Gehm S, Brandt M, Ballay P, Godde B. Not only age but also tactile perception influences the preference for cosmetic creams applied to the forearm. Int J Cosmet Sci 2016; 39:344-350. [PMID: 27864955 DOI: 10.1111/ics.12382] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 10/31/2016] [Indexed: 11/27/2022]
Abstract
OBJECTIVE We aimed to examine whether and how age as well as tactile sensitivity and perception had an impact on how women liked richer and lighter creams. Furthermore, the question arose if age and tactile perception had an influence on the ability to distinguish between the creams and how the ability to distinguish between creams influenced the liking of these creams. METHODS A total of 299 female participants were invited to rate how much they liked four different cosmetic creams applied to their forearms. The creams were based on the same base formula but differed with respect to the texture. In order to arouse the impression of more lightness (quasi-light) or more richness (quasi-rich), polyethylene particles of different sizes were added to the base formula. First of all, the participants were tested for their tactile sensitivity and perception. Tactile sensitivity was tested by Von Frey filaments, tactile spatial perception by the tactile Landolt ring test and the ability to discriminate surface structures by a sandpaper test. Furthermore, the participants rated the creams with respect to the acceptance, the subjective skin feeling after application and performed paired-comparison tests. Analyses of variance and regression analyses were applied to the data. RESULTS In general, participants liked quasi-rich creams less than quasi-light creams. However, older women compared to younger women and women with lower tactile performance in comparison with women with higher tactile performance revealed a weaker influence of cream type-specific acceptance ratings. Further results revealed that young participants perceived the quasi-light creams (with particles of ~50 μm diameter) as soft and quasi-rich creams (with particles of ~100 μm and ~165 μm diameter), as coarse. In contrast, this subjective skin feeling after application in participants at age 50 and older did not differ much. CONCLUSION Age and tactile perceptual abilities have additive effects on the acceptance of creams with different textures when applied to the forearm.
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Schmauder S, Brandt M, Werner A. Das CADASIL-Syndrom als Differentialdiagnose eines postpartalen HELLP-Syndroms. Geburtshilfe Frauenheilkd 2016. [DOI: 10.1055/s-0036-1583563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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53
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Pirkkalainen JM, Damskägg E, Brandt M, Massel F, Sillanpää MA. Squeezing of Quantum Noise of Motion in a Micromechanical Resonator. PHYSICAL REVIEW LETTERS 2015; 115:243601. [PMID: 26705631 DOI: 10.1103/physrevlett.115.243601] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Indexed: 06/05/2023]
Abstract
A pair of conjugate observables, such as the quadrature amplitudes of harmonic motion, have fundamental fluctuations that are bound by the Heisenberg uncertainty relation. However, in a squeezed quantum state, fluctuations of a quantity can be reduced below the standard quantum limit, at the cost of increased fluctuations of the conjugate variable. Here we prepare a nearly macroscopic moving body, realized as a micromechanical resonator, in a squeezed quantum state. We obtain squeezing of one quadrature amplitude 1.1±0.4 dB below the standard quantum limit, thus achieving a long-standing goal of obtaining motional squeezing in a macroscopic object.
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DiNardo CD, Jabbour E, Ravandi F, Takahashi K, Daver N, Routbort M, Patel KP, Brandt M, Pierce S, Kantarjian H, Garcia-Manero G. IDH1 and IDH2 mutations in myelodysplastic syndromes and role in disease progression. Leukemia 2015; 30:980-4. [PMID: 26228814 PMCID: PMC4733599 DOI: 10.1038/leu.2015.211] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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He S, Chousterman BG, Fenn A, Anzai A, Nairz M, Brandt M, Hilgendorf I, Sun Y, Ye YX, Iwamoto Y, Tricot B, Weissleder R, Macphee C, Libby P, Nahrendorf M, Swirski FK. Lp-PLA2 Antagonizes Left Ventricular Healing After Myocardial Infarction by Impairing the Appearance of Reparative Macrophages. Circ Heart Fail 2015; 8:980-7. [PMID: 26232205 PMCID: PMC4568849 DOI: 10.1161/circheartfailure.115.002334] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 07/27/2015] [Indexed: 12/03/2022]
Abstract
Supplemental Digital Content is available in the text. Healing after myocardial infarction (MI) involves the biphasic accumulation of inflammatory Ly-6Chigh and reparative Ly-6Clow monocytes/macrophages. Excessive inflammation disrupts the balance between the 2 phases, impairs infarct healing, and contributes to left ventricle remodeling and heart failure. Lipoprotein-associated phospholipase A2 (Lp-PLA2), a member of the phospholipase A2 family of enzymes, produced predominantly by leukocytes, participates in host defenses and disease. Elevated Lp-PLA2 levels associate with increased risk of cardiovascular events across diverse patient populations, but the mechanisms by which the enzyme elicits its effects remain unclear. This study tested the role of Lp-PLA2 in healing after MI.
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Crawford GL, Boldison J, Copland DA, Adamson P, Gale D, Brandt M, Nicholson LB, Dick AD. The role of lipoprotein-associated phospholipase A2 in a murine model of experimental autoimmune uveoretinitis. PLoS One 2015; 10:e0122093. [PMID: 25874928 PMCID: PMC4398387 DOI: 10.1371/journal.pone.0122093] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Accepted: 02/21/2015] [Indexed: 12/22/2022] Open
Abstract
Macrophage activation is, in part, regulated via hydrolysis of oxidised low density lipoproteins by Lipoprotein-Associated phospholipase A2 (Lp-PLA2), resulting in increased macrophage migration, pro-inflammatory cytokine release and chemokine expression. In uveitis, tissue damage is mediated as a result of macrophage activation; hence inhibition of Lp-PLA2 may limit macrophage activation and protect the tissue. Utilising Lp-PLA2 gene-deficient (KO) mice and a pharmacological inhibitor of Lp-PLA2 (SB-435495) we aimed to determine the effect of Lp-PLA2 suppression in mediating retinal protection in a model of autoimmune retinal inflammation, experimental autoimmune uveoretinitis (EAU). Following immunisation with RBP-3 (IRBP) 1–20 or 161–180 peptides, clinical disease was monitored and severity assessed, infiltrating leukocytes were enumerated by flow cytometry and tissue destruction quantified by histology. Despite ablation of Lp-PLA2 enzyme activity in Lp-PLA2 KO mice or wild-type mice treated with SB-435495, the number of infiltrating CD45+ cells in the retina was equivalent to control EAU animals, and there was no reduction in disease severity. Thus, despite the reported beneficial effects of therapeutic Lp-PLA2 depletion in a variety of vascular inflammatory conditions, we were unable to attenuate disease, show delayed disease onset or prevent progression of EAU in Lp-PLA2 KO mice. Although EAU exhibits inflammatory vasculopathy there is no overt defect in lipid metabolism and given the lack of effect following Lp-PLA2 suppression, these data support the hypothesis that sub-acute autoimmune inflammatory disease progresses independently of Lp-PLA2 activity.
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Brandt M, Mbow C, Diouf AA, Verger A, Samimi C, Fensholt R. Ground- and satellite-based evidence of the biophysical mechanisms behind the greening Sahel. GLOBAL CHANGE BIOLOGY 2015; 21:1610-1620. [PMID: 25400243 DOI: 10.1111/gcb.12807] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 11/05/2014] [Accepted: 11/08/2014] [Indexed: 06/04/2023]
Abstract
After a dry period with prolonged droughts in the 1970s and 1980s, recent scientific outcome suggests that the decades of abnormally dry conditions in the Sahel have been reversed by positive anomalies in rainfall. Various remote sensing studies observed a positive trend in vegetation greenness over the last decades which is known as the re-greening of the Sahel. However, little investment has been made in including long-term ground-based data collections to evaluate and better understand the biophysical mechanisms behind these findings. Thus, deductions on a possible increment in biomass remain speculative. Our aim is to bridge these gaps and give specifics on the biophysical background factors of the re-greening Sahel. Therefore, a trend analysis was applied on long time series (1987-2013) of satellite-based vegetation and rainfall data, as well as on ground-observations of leaf biomass of woody species, herb biomass, and woody species abundance in different ecosystems located in the Sahel zone of Senegal. We found that the positive trend observed in satellite vegetation time series (+36%) is caused by an increment of in situ measured biomass (+34%), which is highly controlled by precipitation (+40%). Whereas herb biomass shows large inter-annual fluctuations rather than a clear trend, leaf biomass of woody species has doubled within 27 years (+103%). This increase in woody biomass did not reflect on biodiversity with 11 of 16 woody species declining in abundance over the period. We conclude that the observed greening in the Senegalese Sahel is primarily related to an increasing tree cover that caused satellite-driven vegetation indices to increase with rainfall reversal.
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Kurosch M, Mager R, Gust K, Brandt M, Borgmann H, Haferkamp A. [Therapy of overactive bladder (OAB)]. Urologe A 2015; 54:567-74; quiz 575-6. [PMID: 25758236 DOI: 10.1007/s00120-015-3770-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Overactive bladder (OAB) is a symptom complex which is present in approximately 17% of the European population. It is observed in the presence or absence of incontinence (wet or dry) and is associated with a high degree of psychological stress as well as high costs for the healthcare system. Myogenic, urothelial and neurogenic factors lead to frequently unknown changes of muscular, neural and connective tissue. For the definition, etiology and diagnostics of the disease the previous continuing medical education (CME) article "Diagnosis of overactive bladder (OAB)" should be consulted. In recent years some improvements have been made in OAB-related research, in terms of pathophysiological models and new pharmacological approaches with the development of new therapeutic agents. Besides classical substances, recently approved agents are increasingly being used for the therapy of OAB. Furthermore, non-pharmaceutical approaches and surgical techniques still play an important role in the therapy of OAB.
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Kurosch M, Mager R, Gust K, Brandt M, Borgmann H, Haferkamp A. Diagnostik der überaktiven Blase (OAB). Urologe A 2015; 54:421-7; quiz 428-9. [DOI: 10.1007/s00120-014-3718-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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60
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McCabe MT, Graves AP, Ganji G, Ott H, Diaz E, Halsey WS, Jiang Y, Smitheman KN, Pappalardi MB, Allen KE, Chen S, Della-Pietra A, Dul E, Hughes AM, Thrall SH, Tummino PJ, Kruger RG, Brandt M, Schwartz B, Verma SK, Creasy CL. Abstract 1057: Mutation of EZH2 A677 in human B-cell lymphoma promotes hyper-trimethylation of H3K27. Mol Cell Biol 2014. [DOI: 10.1158/1538-7445.am2012-1057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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61
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Brandt M, Nieuwkamp M, Kerkdijk E, Verschuur E. L28 Huntington Speech Music Therapy. A Therapy Based On The Principles Of The Speech Music Therapy For Aphasia, Adjusted For Patients With Huntington. J Neurol Psychiatry 2014. [DOI: 10.1136/jnnp-2014-309032.265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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62
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Van Aller GS, Pappalardi MB, Ott HM, Diaz E, Brandt M, Schwartz BJ, Miller WH, Dhanak D, McCabe MT, Verma SK, Creasy CL, Tummino PJ, Kruger RG. Long residence time inhibition of EZH2 in activated polycomb repressive complex 2. ACS Chem Biol 2014; 9:622-9. [PMID: 24304166 DOI: 10.1021/cb4008748] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
EZH2/PRC2 catalyzes transcriptionally repressive methylation at lysine 27 of histone H3 and has been associated with numerous cancer types. Point mutations in EZH2 at Tyr641 and Ala677 identified in non-Hodgkin lymphomas alter substrate specificity and result in increased trimethylation at histone H3K27. Interestingly, EZH2/PRC2 is activated by binding H3K27me3 marks on histones, and this activation is proposed as a mechanism for self-propagation of gene silencing. Recent work has identified GSK126 as a potent, selective, SAM-competitive inhibitor of EZH2 capable of globally decreasing H3K27 trimethylation in cells. Here we show that activation of PRC2 by an H3 peptide trimethylated at K27 is primarily an effect on the rate-limiting step (kcat) with no effect on substrate binding (Km). Additionally, GSK126 is shown to have a significantly longer residence time of inhibition on the activated form of EZH2/PRC2 as compared to unactivated EZH2/PRC2. Overall inhibition constant (Ki*) values for GSK126 were determined to be as low as 93 pM and appear to be driven by slow dissociation of inhibitor from the activated enzyme. The data suggest that activation of EZH2 allows the enzyme to adopt a conformation that possesses greater affinity for GSK126. The long residence time of GSK126 may be beneficial in vivo and may result in durable target inhibition after drug systemic clearance.
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Ravandi F, Arana Yi C, Cortes JE, Levis M, Faderl S, Garcia-Manero G, Jabbour E, Konopleva M, O'Brien S, Estrov Z, Borthakur G, Thomas D, Pierce S, Brandt M, Pratz K, Luthra R, Andreeff M, Kantarjian H. Final report of phase II study of sorafenib, cytarabine and idarubicin for initial therapy in younger patients with acute myeloid leukemia. Leukemia 2014; 28:1543-5. [PMID: 24487412 DOI: 10.1038/leu.2014.54] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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64
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Gilmartin AG, Faitg TH, Richter M, Groy A, Seefeld MA, Darcy MG, Peng X, Federowicz K, Yang J, Zhang SY, Minthorn E, Jaworski JP, Schaber M, Martens S, McNulty DE, Sinnamon RH, Zhang H, Kirkpatrick RB, Nevins N, Cui G, Pietrak B, Diaz E, Jones A, Brandt M, Schwartz B, Heerding DA, Kumar R. Allosteric Wip1 phosphatase inhibition through flap-subdomain interaction. Nat Chem Biol 2014; 10:181-7. [PMID: 24390428 DOI: 10.1038/nchembio.1427] [Citation(s) in RCA: 166] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 10/21/2013] [Indexed: 12/22/2022]
Abstract
Although therapeutic interventions of signal-transduction cascades with targeted kinase inhibitors are a well-established strategy, drug-discovery efforts to identify targeted phosphatase inhibitors have proven challenging. Herein we report a series of allosteric, small-molecule inhibitors of wild-type p53-induced phosphatase (Wip1), an oncogenic phosphatase common to multiple cancers. Compound binding to Wip1 is dependent on a 'flap' subdomain located near the Wip1 catalytic site that renders Wip1 structurally divergent from other members of the protein phosphatase 2C (PP2C) family and that thereby confers selectivity for Wip1 over other phosphatases. Treatment of tumor cells with the inhibitor GSK2830371 increases phosphorylation of Wip1 substrates and causes growth inhibition in both hematopoietic tumor cell lines and Wip1-amplified breast tumor cells harboring wild-type TP53. Oral administration of Wip1 inhibitors in mice results in expected pharmacodynamic effects and causes inhibition of lymphoma xenograft growth. To our knowledge, GSK2830371 is the first orally active, allosteric inhibitor of Wip1 phosphatase.
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Van Den Borne P, Haverslag RT, Brandt M, Cheng C, Duckers HJ, Quax PHA, Hoefer IE, Pasterkamp G, De Kleijn DPV. Chemokine (c-x-c motif) ligand 10 deficiency causes impairment of perfusion recovery after local arterial occlusion. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht310.4367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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66
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Brandt M, Sun S, Alam N, Bendeich P, Bishop A. Laser cladding repair of turbine blades in power plants: from research to commercialisation. ACTA ACUST UNITED AC 2013. [DOI: 10.1179/174951409x12542264513843] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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67
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Cottam R, Luzin V, Liu Q, Wong YC, Wang J, Brandt M. Investigation into Heat Treatment and Residual Stress in Laser Clad AA7075 Powder on AA7075 Substrate. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s13632-013-0080-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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68
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Brandt M, Szewczuk LM, Zhang H, Hong X, McCormick PM, Lewis TS, Graham TI, Hung ST, Harper-Jones AD, Kerrigan JJ, Wang DY, Dul E, Hou W, Ho TF, Meek TD, Cheung MH, Johanson KO, Jones CS, Schwartz B, Kumar S, Oliff AI, Kirkpatrick RB. Development of a High-Throughput Screen to Detect Inhibitors of TRPS1 Sumoylation. Assay Drug Dev Technol 2013; 11:308-25. [DOI: 10.1089/adt.2012.501] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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69
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Waizy H, Plaass C, Brandt M, Herold D, Stukenborg-Colsman C, Windhagen H, Claassen L. Extraartikuläre Arthrorise nach Grice/Green vs. Kalkaneusverlängerungsosteotomie nach Evans. DER ORTHOPADE 2013; 42:409-17. [DOI: 10.1007/s00132-013-2090-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Thalji RK, McAtee JJ, Belyanskaya S, Brandt M, Brown GD, Costell MH, Ding Y, Dodson JW, Eisennagel SH, Fries RE, Gross JW, Harpel MR, Holt DA, Israel DI, Jolivette LJ, Krosky D, Li H, Lu Q, Mandichak T, Roethke T, Schnackenberg CG, Schwartz B, Shewchuk LM, Xie W, Behm DJ, Douglas SA, Shaw AL, Marino JP. Discovery of 1-(1,3,5-triazin-2-yl)piperidine-4-carboxamides as inhibitors of soluble epoxide hydrolase. Bioorg Med Chem Lett 2013; 23:3584-8. [PMID: 23664879 DOI: 10.1016/j.bmcl.2013.04.019] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 04/05/2013] [Accepted: 04/08/2013] [Indexed: 10/27/2022]
Abstract
1-(1,3,5-Triazin-yl)piperidine-4-carboxamide inhibitors of soluble epoxide hydrolase were identified from high through-put screening using encoded library technology. The triazine heterocycle proved to be a critical functional group, essential for high potency and P450 selectivity. Phenyl group substitution was important for reducing clearance, and establishing good oral exposure. Based on this lead optimization work, 1-[4-methyl-6-(methylamino)-1,3,5-triazin-2-yl]-N-{[[4-bromo-2-(trifluoromethoxy)]-phenyl]methyl}-4-piperidinecarboxamide (27) was identified as a useful tool compound for in vivo investigation. Robust effects on a serum biomarker, 9, 10-epoxyoctadec-12(Z)-enoic acid (the epoxide derived from linoleic acid) were observed, which provided evidence of robust in vivo target engagement and the suitability of 27 as a tool compound for study in various disease models.
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McCabe MT, Ott HM, Ganji G, Korenchuk S, Thompson C, Van Aller GS, Liu Y, Graves AP, Della Pietra A, Diaz E, LaFrance LV, Mellinger M, Duquenne C, Tian X, Kruger RG, McHugh CF, Brandt M, Miller WH, Dhanak D, Verma SK, Tummino PJ, Creasy CL. EZH2 inhibition as a therapeutic strategy for lymphoma with EZH2-activating mutations. Nature 2012; 492:108-12. [PMID: 23051747 DOI: 10.1038/nature11606] [Citation(s) in RCA: 1375] [Impact Index Per Article: 114.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 09/24/2012] [Indexed: 12/24/2022]
Abstract
In eukaryotes, post-translational modification of histones is critical for regulation of chromatin structure and gene expression. EZH2 is the catalytic subunit of the polycomb repressive complex 2 (PRC2) and is involved in repressing gene expression through methylation of histone H3 on lysine 27 (H3K27). EZH2 overexpression is implicated in tumorigenesis and correlates with poor prognosis in several tumour types. Additionally, somatic heterozygous mutations of Y641 and A677 residues within the catalytic SET domain of EZH2 occur in diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma. The Y641 residue is the most frequently mutated residue, with up to 22% of germinal centre B-cell DLBCL and follicular lymphoma harbouring mutations at this site. These lymphomas have increased H3K27 tri-methylation (H3K27me3) owing to altered substrate preferences of the mutant enzymes. However, it is unknown whether specific, direct inhibition of EZH2 methyltransferase activity will be effective in treating EZH2 mutant lymphomas. Here we demonstrate that GSK126, a potent, highly selective, S-adenosyl-methionine-competitive, small-molecule inhibitor of EZH2 methyltransferase activity, decreases global H3K27me3 levels and reactivates silenced PRC2 target genes. GSK126 effectively inhibits the proliferation of EZH2 mutant DLBCL cell lines and markedly inhibits the growth of EZH2 mutant DLBCL xenografts in mice. Together, these data demonstrate that pharmacological inhibition of EZH2 activity may provide a promising treatment for EZH2 mutant lymphoma.
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MESH Headings
- Animals
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Enhancer of Zeste Homolog 2 Protein
- Gene Expression Regulation, Neoplastic/drug effects
- Gene Silencing/drug effects
- Histone Methyltransferases
- Histone-Lysine N-Methyltransferase/antagonists & inhibitors
- Histone-Lysine N-Methyltransferase/genetics
- Histone-Lysine N-Methyltransferase/metabolism
- Histones/chemistry
- Histones/metabolism
- Humans
- Indoles/pharmacology
- Indoles/therapeutic use
- Lymphoma, Follicular/drug therapy
- Lymphoma, Follicular/enzymology
- Lymphoma, Follicular/genetics
- Lymphoma, Follicular/pathology
- Lymphoma, Large B-Cell, Diffuse/drug therapy
- Lymphoma, Large B-Cell, Diffuse/enzymology
- Lymphoma, Large B-Cell, Diffuse/genetics
- Lymphoma, Large B-Cell, Diffuse/pathology
- Methylation/drug effects
- Mice
- Mutation/genetics
- Neoplasm Transplantation
- Polycomb Repressive Complex 2/antagonists & inhibitors
- Polycomb Repressive Complex 2/genetics
- Polycomb Repressive Complex 2/metabolism
- Pyridones/pharmacology
- Pyridones/therapeutic use
- Repressor Proteins/chemistry
- Repressor Proteins/metabolism
- Transcriptional Activation/drug effects
- Transplantation, Heterologous
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Muñoz Ramirez J, Galera Fernandez F, Silván Bueno A, Brandt M, Garcia Fernandez J, Garijo Lopez E. Importance of multinucleation at 2-cell stage: study in a time-lapse incubator. Fertil Steril 2012. [DOI: 10.1016/j.fertnstert.2012.07.623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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73
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Diaz E, Machutta CA, Chen S, Jiang Y, Nixon C, Hofmann G, Key D, Sweitzer S, Patel M, Wu Z, Creasy CL, Kruger RG, LaFrance L, Verma SK, Pappalardi MB, Le B, Van Aller GS, McCabe MT, Tummino PJ, Pope AJ, Thrall SH, Schwartz B, Brandt M. Development and validation of reagents and assays for EZH2 peptide and nucleosome high-throughput screens. ACTA ACUST UNITED AC 2012; 17:1279-92. [PMID: 22904200 DOI: 10.1177/1087057112453765] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Histone methyltransferases (HMT) catalyze the methylation of histone tail lysines, resulting in changes in gene transcription. Misregulation of these enzymes has been associated with various forms of cancer, making this target class a potential new area for the development of novel chemotherapeutics. EZH2 is the catalytic component of the polycomb group repressive complex (PRC2), which selectively methylates histone H3 lysine 27 (H3K27). EZH2 is overexpressed in prostate, breast, bladder, brain, and other tumor types and is recognized as a molecular marker for cancer progression and aggressiveness. Several new reagents and assays were developed to aid in the identification of EZH2 inhibitors, and these were used to execute two high-throughput screening campaigns. Activity assays using either an H3K27 peptide or nucleosomes as substrates for methylation are described. The strategy to screen EZH2 with either a surrogate peptide or a natural substrate led to the identification of the same tractable series. Compounds from this series are reversible, are [(3)H]-S-adenosyl-L-methionine competitive, and display biochemical inhibition of H3K27 methylation.
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Boywitt CD, Brandt M. The primacy effect in memory for repetitions: Evidence for the role of lag between repetitions in source monitoring. JOURNAL OF COGNITIVE PSYCHOLOGY 2012. [DOI: 10.1080/20445911.2011.617303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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75
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Diaz E, McCabe MT, Jiang Y, Chen S, Pappalardi M, Smitheman K, Della Pietra A, Graves A, Kruger R, Brandt M, Sweitzer S, Schwartz B, Tummino PJ, Creasy CL. Abstract LB-186: Somatic Y641 mutations in EZH2 alter the balance of di- and tri-methylation of H3K27 in diffuse large B-cell lymphomas. Cancer Res 2011. [DOI: 10.1158/1538-7445.am2011-lb-186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
EZH2 is the catalytic subunit of the Polycomb Repressive Complex 2 (PRC2) responsible for methylating histone H3 on lysine 27 (H3K27) and repressing transcription of target genes. PRC2 activity is essential for maintaining the self-renewal capacity of embryonic and adult stem cells and the dynamic regulation of this activity is critical for proper development and differentiation. Dysregulation of H3K27 methylation is implicated in tumorigenesis and occurs through multiple mechanisms. Elevated levels of EZH2 are known to correlate with poor prognosis in a number of solid tumors including prostate and breast. Inactivating mutations in UTX, an H3K27 demethylase which acts in opposition to EZH2, have been described in several tumor types including multiple myeloma, esophageal squamous cell carcinoma, and renal cell carcinoma. More recently, somatic mutations in EZH2 were identified in myelodysplastic syndrome (MDS), follicular lymphoma (FL), and GCB diffuse large B cell lymphoma (DLBCL). While the mutations in MDS are often homozygous and encompass missense, nonsense, and frame shift mutations at multiple regions of the protein, the mutations in DLBCL and FL are heterozygous and occur at a single residue (Y641) suggesting that the effect of these mutations on PRC2 activity could be quite different between MDS and lymphoma. Utilizing a biochemical approach with recombinant PRC2 containing either wild-type or mutant EZH2, we demonstrate that Y641 mutants exhibit an altered substrate preference. In contrast to wild-type EZH2 which prefers an unmodified or mono-methylated K27 residue, Y641 mutants act primarily on a di-methylated H3K27 with little activity for unmodified or mono-methylated K27. Consistent with these biochemical data, we find that when compared to wild-type lymphoma cell lines those harboring Y641 mutations have elevated levels of H3K27me3 and reduced H3K27me2. To further characterize the substrate specificity of PRC2 complexes containing either WT or mutant EZH2, we utilized an epigenetic peptide library which contained unmodified and modified peptides from histone H2A, H2B, H3 and H4. In addition, we have conducted cell-based studies to understand the effect of these mutations on H3 methylation and the regulation of EZH2 target genes. These data and the implications of these findings for the treatment of FL and DLBCL will be discussed.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-186. doi:10.1158/1538-7445.AM2011-LB-186
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