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Babl N, Decking SM, Voll F, Althammer M, Sala-Hojman A, Ferretti R, Korf C, Schmidl C, Schmidleithner L, Nerb B, Matos C, Koehl GE, Siska P, Bruss C, Kellermeier F, Dettmer K, Oefner PJ, Wichland M, Ugele I, Bohr C, Herr W, Ramaswamy S, Heinrich T, Herhaus C, Kreutz M, Renner K. MCT4 blockade increases the efficacy of immune checkpoint blockade. J Immunother Cancer 2023; 11:e007349. [PMID: 37880183 PMCID: PMC10603342 DOI: 10.1136/jitc-2023-007349] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/18/2023] [Indexed: 10/27/2023] Open
Abstract
BACKGROUND & AIMS Intratumoral lactate accumulation and acidosis impair T-cell function and antitumor immunity. Interestingly, expression of the lactate transporter monocarboxylate transporter (MCT) 4, but not MCT1, turned out to be prognostic for the survival of patients with rectal cancer, indicating that single MCT4 blockade might be a promising strategy to overcome glycolysis-related therapy resistance. METHODS To determine whether blockade of MCT4 alone is sufficient to improve the efficacy of immune checkpoint blockade (ICB) therapy, we examined the effects of the selective MCT1 inhibitor AZD3965 and a novel MCT4 inhibitor in a colorectal carcinoma (CRC) tumor spheroid model co-cultured with blood leukocytes in vitro and the MC38 murine CRC model in vivo in combination with an antibody against programmed cell death ligand-1(PD-L1). RESULTS Inhibition of MCT4 was sufficient to reduce lactate efflux in three-dimensional (3D) CRC spheroids but not in two-dimensional cell-cultures. Co-administration of the MCT4 inhibitor and ICB augmented immune cell infiltration, T-cell function and decreased CRC spheroid viability in a 3D co-culture model of human CRC spheroids with blood leukocytes. Accordingly, combination of MCT4 and ICB increased intratumoral pH, improved leukocyte infiltration and T-cell activation, delayed tumor growth, and prolonged survival in vivo. MCT1 inhibition exerted no further beneficial impact. CONCLUSIONS These findings demonstrate that single MCT4 inhibition represents a novel therapeutic approach to reverse lactic-acid driven immunosuppression and might be suitable to improve ICB efficacy.
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Affiliation(s)
- Nathalie Babl
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
| | - Sonja-Maria Decking
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
- Department of Otorhinolaryngology, University Hospital Regensburg, Regensburg, Germany
- Leibniz Institute for Immunotherapy, Regensburg, Germany
| | - Florian Voll
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
- Leibniz Institute for Immunotherapy, Regensburg, Germany
| | - Michael Althammer
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
| | | | - Roberta Ferretti
- EMD Serono Research and Development Institute, Inc, Billerica, Massachusetts, USA, an affiliate of Merck KGaA
| | - Clarissa Korf
- Department of Otorhinolaryngology, University Hospital Regensburg, Regensburg, Germany
| | | | | | - Benedikt Nerb
- Leibniz Institute for Immunotherapy, Regensburg, Germany
| | - Carina Matos
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
| | - Gudrun E Koehl
- Department of Surgery, University Hospital Regensburg, Regensburg, Germany
| | - Peter Siska
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
| | - Christina Bruss
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
- Department of Gynecology and Obstetrics, University Hospital Regensburg, Regensburg, Germany
| | - Fabian Kellermeier
- Institute of Functional Genomics, University of Regensburg, Regensburg, Germany
| | - Katja Dettmer
- Institute of Functional Genomics, University of Regensburg, Regensburg, Germany
| | - Peter J Oefner
- Institute of Functional Genomics, University of Regensburg, Regensburg, Germany
| | - Marvin Wichland
- Department of Otorhinolaryngology, University Hospital Regensburg, Regensburg, Germany
| | - Ines Ugele
- Department of Otorhinolaryngology, University Hospital Regensburg, Regensburg, Germany
| | - Christopher Bohr
- Department of Otorhinolaryngology, University Hospital Regensburg, Regensburg, Germany
| | - Wolfgang Herr
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
| | - Shivapriya Ramaswamy
- EMD Serono Research and Development Institute, Inc, Billerica, Massachusetts, USA, an affiliate of Merck KGaA
| | | | | | - Marina Kreutz
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
- Leibniz Institute for Immunotherapy, Regensburg, Germany
| | - Kathrin Renner
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
- Department of Otorhinolaryngology, University Hospital Regensburg, Regensburg, Germany
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Heinrich T, Sala-Hojman A, Ferretti R, Petersson C, Minguzzi S, Gondela A, Ramaswamy S, Bartosik A, Czauderna F, Crowley L, Wahra P, Schilke H, Böpple P, Dudek Ł, Leś M, Niedziejko P, Olech K, Pawlik H, Włoszczak Ł, Zuchowicz K, Suarez Alvarez JR, Martyka J, Sitek E, Mikulski M, Szczęśniak J, Jäckel S, Krier M, Król M, Wegener A, Gałęzowski M, Nowak M, Becker F, Herhaus C. Discovery of 5-{2-[5-Chloro-2-(5-ethoxyquinoline-8-sulfonamido)phenyl]ethynyl}-4-methoxypyridine-2-carboxylic Acid, a Highly Selective in Vivo Useable Chemical Probe to Dissect MCT4 Biology. J Med Chem 2021; 64:11904-11933. [PMID: 34382802 DOI: 10.1021/acs.jmedchem.1c00448] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 11/29/2022]
Abstract
Due to increased lactate production during glucose metabolism, tumor cells heavily rely on efficient lactate transport to avoid intracellular lactate accumulation and acidification. Monocarboxylate transporter 4 (MCT4/SLC16A3) is a lactate transporter that plays a central role in tumor pH modulation. The discovery and optimization of a novel class of MCT4 inhibitors (hit 9a), identified by a cellular screening in MDA-MB-231, is described. Direct target interaction of the optimized compound 18n with the cytosolic domain of MCT4 was shown after solubilization of the GFP-tagged transporter by fluorescence cross-correlation spectroscopy and microscopic studies. In vitro treatment with 18n resulted in lactate efflux inhibition and reduction of cellular viability in MCT4 high expressing cells. Moreover, pharmacokinetic properties of 18n allowed assessment of lactate modulation and antitumor activity in a mouse tumor model. Thus, 18n represents a valuable tool for investigating selective MCT4 inhibition and its effect on tumor biology.
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Affiliation(s)
- Timo Heinrich
- Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Ada Sala-Hojman
- Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Roberta Ferretti
- EMD Serono Research & Development Institute, Inc., 45A Middlesex Turnpike, Billerica, Massachusetts 01821, United States
| | - Carl Petersson
- Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Stefano Minguzzi
- Intana, Bioscience GmbH, Lochhamer Str. 29a, 82152 Planegg, Martinsried, Germany
| | | | - Shivapriya Ramaswamy
- EMD Serono Research & Development Institute, Inc., 45A Middlesex Turnpike, Billerica, Massachusetts 01821, United States
| | - Anna Bartosik
- Ryvu Therapeutics, Sternbacha 2, 30-394 Kraków, Poland
| | - Frank Czauderna
- EMD Serono Research & Development Institute, Inc., 45A Middlesex Turnpike, Billerica, Massachusetts 01821, United States
| | - Lindsey Crowley
- EMD Serono Research & Development Institute, Inc., 45A Middlesex Turnpike, Billerica, Massachusetts 01821, United States
| | - Pamela Wahra
- EMD Serono Research & Development Institute, Inc., 45A Middlesex Turnpike, Billerica, Massachusetts 01821, United States
| | - Heike Schilke
- Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Pia Böpple
- Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Łukasz Dudek
- Ryvu Therapeutics, Sternbacha 2, 30-394 Kraków, Poland
| | - Marcin Leś
- Ryvu Therapeutics, Sternbacha 2, 30-394 Kraków, Poland
| | | | - Kamila Olech
- Ryvu Therapeutics, Sternbacha 2, 30-394 Kraków, Poland
| | - Henryk Pawlik
- Ryvu Therapeutics, Sternbacha 2, 30-394 Kraków, Poland
| | | | | | | | | | - Ewa Sitek
- Ryvu Therapeutics, Sternbacha 2, 30-394 Kraków, Poland
| | | | | | - Sven Jäckel
- Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Mireille Krier
- Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Marcin Król
- Ryvu Therapeutics, Sternbacha 2, 30-394 Kraków, Poland
| | - Ansgar Wegener
- Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | | | - Mateusz Nowak
- Ryvu Therapeutics, Sternbacha 2, 30-394 Kraków, Poland
| | - Frank Becker
- Intana, Bioscience GmbH, Lochhamer Str. 29a, 82152 Planegg, Martinsried, Germany
| | - Christian Herhaus
- Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
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Digles D, Zdrazil B, Neefs JM, Van Vlijmen H, Herhaus C, Caracoti A, Brea J, Roibás B, Loza MI, Queralt-Rosinach N, Furlong LI, Gaulton A, Bartek L, Senger S, Chichester C, Engkvist O, Evelo CT, Franklin NI, Marren D, Ecker GF, Jacoby E. Open PHACTS computational protocols for in silico target validation of cellular phenotypic screens: knowing the knowns. Medchemcomm 2016; 7:1237-1244. [PMID: 27774140 PMCID: PMC5063042 DOI: 10.1039/c6md00065g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/10/2016] [Indexed: 01/09/2023]
Abstract
Phenotypic screening is in a renaissance phase and is expected by many academic and industry leaders to accelerate the discovery of new drugs for new biology. Given that phenotypic screening is per definition target agnostic, the emphasis of in silico and in vitro follow-up work is on the exploration of possible molecular mechanisms and efficacy targets underlying the biological processes interrogated by the phenotypic screening experiments. Herein, we present six exemplar computational protocols for the interpretation of cellular phenotypic screens based on the integration of compound, target, pathway, and disease data established by the IMI Open PHACTS project. The protocols annotate phenotypic hit lists and allow follow-up experiments and mechanistic conclusions. The annotations included are from ChEMBL, ChEBI, GO, WikiPathways and DisGeNET. Also provided are protocols which select from the IUPHAR/BPS Guide to PHARMACOLOGY interaction file selective compounds to probe potential targets and a correlation robot which systematically aims to identify an overlap of active compounds in both the phenotypic as well as any kinase assay. The protocols are applied to a phenotypic pre-lamin A/C splicing assay selected from the ChEMBL database to illustrate the process. The computational protocols make use of the Open PHACTS API and data and are built within the Pipeline Pilot and KNIME workflow tools.
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Affiliation(s)
- D Digles
- Department of Pharmaceutical Chemistry , University of Vienna , Pharmacoinformatics Research Group , Althanstraße 14 , 1090 Wien , Austria .
| | - B Zdrazil
- Department of Pharmaceutical Chemistry , University of Vienna , Pharmacoinformatics Research Group , Althanstraße 14 , 1090 Wien , Austria .
| | - J-M Neefs
- Janssen Research & Development , Turnhoutseweg 30 , B-2340 Beerse , Belgium .
| | - H Van Vlijmen
- Janssen Research & Development , Turnhoutseweg 30 , B-2340 Beerse , Belgium .
| | - C Herhaus
- Merck KGaA, Merck Serono R&D , Computational Chemistry , Frankfurter Straße 250 , 64293 Darmstadt , Germany
| | - A Caracoti
- BIOVIA , a Dassault Systèmes brand , 334 Cambridge Science Park , Cambridge CB4 0WN , UK
| | - J Brea
- Grupo BioFarma-USEF , Departamento de Farmacología , Facultad de Farmacia , Campus Universitario Sur s/n , 15782 Santiago de Compostela , Spain
| | - B Roibás
- Grupo BioFarma-USEF , Departamento de Farmacología , Facultad de Farmacia , Campus Universitario Sur s/n , 15782 Santiago de Compostela , Spain
| | - M I Loza
- Grupo BioFarma-USEF , Departamento de Farmacología , Facultad de Farmacia , Campus Universitario Sur s/n , 15782 Santiago de Compostela , Spain
| | - N Queralt-Rosinach
- Research Programme on Biomedical Informatics (GRIB) , Hospital del Mar Medical Research Institute (IMIM) , Department of Experimental and Health Sciences , Universitat Pompeu Fabra , C/Dr Aiguader 88 , E-08003 Barcelona , Spain
| | - L I Furlong
- Research Programme on Biomedical Informatics (GRIB) , Hospital del Mar Medical Research Institute (IMIM) , Department of Experimental and Health Sciences , Universitat Pompeu Fabra , C/Dr Aiguader 88 , E-08003 Barcelona , Spain
| | - A Gaulton
- European Molecular Biology Laboratory , European Bioinformatics Institute (EMBL-EBI) , Wellcome Genome Campus , Hinxton , Cambridge CB10 1SD , UK
| | - L Bartek
- GlaxoSmithKline , Medicines Research Centre , Stevenage SG1 2NY , UK
| | - S Senger
- GlaxoSmithKline , Medicines Research Centre , Stevenage SG1 2NY , UK
| | - C Chichester
- Swiss Institute of Bioinformatics , CALIPHO Group , CMU Rue Michel-Servet 1 , 1211 Geneva 4 , Switzerland ; Nestlé Institute of Health Sciences SA , EPFL Innovation Park, Bâtiment H , 1015 Lausanne , Switzerland
| | - O Engkvist
- Chemistry Innovation Centre , Discovery Sciences , AstraZeneca R&D Gothenburg , SE-431 83 Mölndal , Sweden
| | - C T Evelo
- Department of Bioinformatics - BiGCaT , P.O. Box 616 , UNS50 Box19 , NL-6200MD Maastricht , The Netherlands
| | - N I Franklin
- Open Innovation Drug Discovery , Discovery Chemistry Eli Lilly and Company , Lilly Corporate Center , DC 1920 , Indianapolis , IN 46285 , USA
| | - D Marren
- Eli Lilly and Company Ltd. , Lilly Research Centre , Erl Wood Manor, Sunninghill Road , Windlesham , Surrey GU20 6PH , England , UK
| | - G F Ecker
- Department of Pharmaceutical Chemistry , University of Vienna , Pharmacoinformatics Research Group , Althanstraße 14 , 1090 Wien , Austria .
| | - E Jacoby
- Janssen Research & Development , Turnhoutseweg 30 , B-2340 Beerse , Belgium .
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Köster H, Craan T, Brass S, Herhaus C, Zentgraf M, Neumann L, Heine A, Klebe G. A small nonrule of 3 compatible fragment library provides high hit rate of endothiapepsin crystal structures with various fragment chemotypes. J Med Chem 2011; 54:7784-96. [PMID: 21972967 DOI: 10.1021/jm200642w] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Druglike molecules are defined by Lipinski's rule of 5, to characterize fragment thresholds, they have been reduced from 5 to 3 (Astex's rule of 3). They are applied to assemble fragment libraries, and providers use them to select fragments for commercial offer. We question whether these rules are too stringent to compose fragment libraries with candidates exhibiting sufficient room for chemical subsequent growing and merging modifications as appropriate functional groups for chemical transformations are required. Usually these groups exhibit properties as hydrogen bond donors/acceptors and provide entry points for optimization chemistry. We therefore designed a fragment library (364 entries) without strictly applying the rule of 3. For initial screening for endothiapepsin binding, we performed a biochemical cleavage assay of a fluorogenic substrate at 1 mM. "Hits" were defined to inhibit the enzyme by at least 40%. Fifty-five hits were suggested and subsequently soaked into endothiapepsin crystals. Eleven crystal structures could be determined covering fragments with diverse binding modes: (i) direct binding to the catalytic dyad aspartates, (ii) water-mediated binding to the aspartates, (iii) no direct interaction with the dyad. They occupy different specificity pockets. Only 4 of the 11 fragments are consistent with the rule of 3. Restriction to this rule would have limited the fragment hits to a strongly reduced variety of chemotypes.
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Affiliation(s)
- Helene Köster
- Department of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, 35032 Marburg, Germany
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Bertl E, Becker H, Eicher T, Herhaus C, Kapadia G, Bartsch H, Gerhäuser C. Inhibition of endothelial cell functions by novel potential cancer chemopreventive agents. Biochem Biophys Res Commun 2005; 325:287-95. [PMID: 15522231 DOI: 10.1016/j.bbrc.2004.10.032] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Indexed: 12/18/2022]
Abstract
Endothelial cells (EC) play a major role in tumor-induced neovascularization and bridge the gap between a microtumor and growth factors such as nutrients and oxygen supply required for expansion. Immortalized human microvascular endothelial cells (HMEC-1) were utilized to assess anti-endothelial effects of 10 novel potential cancer chemopreventive compounds from various sources that we have investigated previously in a human in vitro anti-angiogenic assay. These include the monoacylphloroglucinol isoaspidinol B, 1,2,5,7-tetrahydroxy-anthraquinone, peracetylated carnosic acid (PCA), isoxanthohumol, 2,2',4'-trimethoxychalcone, 3'-bromo-2,4-dimethoxychalcone as well as four synthetic derivatives of lunularic acid, a bibenzyl found in mosses [Int. J. Cancer Prev. 1 (2004) 47]. EC proliferation was inhibited with half-maximal inhibitory concentrations from 0.3 to 49.6muM, whereas EC migration was affected by most compounds at sub-micromolar concentrations. PCA and the bibenzyl derivative EC 1004 potently prevented differentiation of HMEC-1 into tubule-like structures. Overall, our data indicate that inhibition of endothelial cell function contributes to various extents to the chemopreventive or anti-angiogenic potential of these lead compounds.
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Affiliation(s)
- Elisabeth Bertl
- Division of Toxicology and Cancer Risk Factors, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
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Stanjek V, Herhaus C, Ritgen U, Boland W, Städler E. Changes in the Leaf Surface Chemistry ofApium graveolens(Apiaceae) stimulated by jasmonic acid and perceived by a specialist insect. Helv Chim Acta 2004. [DOI: 10.1002/hlca.19970800507] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Heiser V, Engemann S, Bröcker W, Dunkel I, Boeddrich A, Waelter S, Nordhoff E, Lurz R, Schugardt N, Rautenberg S, Herhaus C, Barnickel G, Böttcher H, Lehrach H, Wanker EE. Identification of benzothiazoles as potential polyglutamine aggregation inhibitors of Huntington's disease by using an automated filter retardation assay. Proc Natl Acad Sci U S A 2002; 99 Suppl 4:16400-6. [PMID: 12200548 PMCID: PMC139900 DOI: 10.1073/pnas.182426599] [Citation(s) in RCA: 166] [Impact Index Per Article: 7.5] [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: 11/18/2022] Open
Abstract
Preventing the formation of insoluble polyglutamine containing protein aggregates in neurons may represent an attractive therapeutic strategy to ameliorate Huntington's disease (HD). Therefore, the ability to screen for small molecules that suppress the self-assembly of huntingtin would have potential clinical and significant research applications. We have developed an automated filter retardation assay for the rapid identification of chemical compounds that prevent HD exon 1 protein aggregation in vitro. Using this method, a total of 25 benzothiazole derivatives that inhibit huntingtin fibrillogenesis in a dose-dependent manner were discovered from a library of approximately 184,000 small molecules. The results obtained by the filter assay were confirmed by immunoblotting, electron microscopy, and mass spectrometry. Furthermore, cell culture studies revealed that 2-amino-4,7-dimethyl-benzothiazol-6-ol, a chemical compound similar to riluzole, significantly inhibits HD exon 1 aggregation in vivo. These findings may provide the basis for a new therapeutic approach to prevent the accumulation of insoluble protein aggregates in Huntington's disease and related glutamine repeat disorders.
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Affiliation(s)
- Volker Heiser
- Max-Planck-Institut für Molekulare Genetik, Ihnestrasse 73, D-14195 Berlin, Germany
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Heiss E, Herhaus C, Klimo K, Bartsch H, Gerhäuser C. Nuclear factor kappa B is a molecular target for sulforaphane-mediated anti-inflammatory mechanisms. J Biol Chem 2001; 276:32008-15. [PMID: 11410599 DOI: 10.1074/jbc.m104794200] [Citation(s) in RCA: 468] [Impact Index Per Article: 20.3] [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: 12/30/2022] Open
Abstract
Sulforaphane (SFN), an aliphatic isothiocyanate, is a known cancer chemopreventive agent. Aiming to investigate anti-inflammatory mechanisms of SFN, we here report a potent decrease in lipopolysaccharide (LPS)-induced secretion of pro-inflammatory and pro-carcinogenic signaling factors in cultured Raw 264.7 macrophages after SFN treatment, i.e. NO, prostaglandin E(2), and tumor necrosis factor alpha. SFN did not directly interact with NO, nor did it inhibit inducible nitric-oxide synthase enzymatic activity. Western blot analyses revealed time- and dose-dependent reduction of LPS-induced inducible nitric-oxide synthase as well as Cox-2 protein expression, which was suppressed at the transcriptional level. To reveal the target of SFN beyond its anti-inflammatory action, we performed electrophoretic mobility shift assay analyses of transcription factor-DNA binding. Consequently, nuclear factor kappa B (NF-kappa B), a pivotal transcription factor in LPS-stimulated pro-inflammatory response, was identified as the key mediator. SFN selectively reduced DNA binding of NF-kappa B without interfering with LPS-induced degradation of the inhibitor of NF-kappa B nor with nuclear translocation of NF-kappa B. Because SFN can interact with thiol groups by dithiocarbamate formation, it may impair the redox-sensitive DNA binding and transactivation of NF-kappa B. Sulforaphane could either directly inactivate NF-kappa B subunits by binding to essential Cys residues or interact with glutathione or other redox regulators like thioredoxin and Ref-1 relevant for NF-kappa B function. Our data provide novel evidence that anti-inflammatory mechanisms contribute to sulforaphane-mediated cancer chemoprevention.
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Affiliation(s)
- E Heiss
- Deutsches Krebsforschungszentrum Heidelberg, Division of Toxicology and Cancer Risk Factors, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
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