51
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Dorard C, Estrada C, Barbotin C, Larcher M, Garancher A, Leloup J, Beermann F, Baccarini M, Pouponnot C, Larue L, Eychène A, Druillennec S. RAF proteins exert both specific and compensatory functions during tumour progression of NRAS-driven melanoma. Nat Commun 2017; 8:15262. [PMID: 28497782 PMCID: PMC5437303 DOI: 10.1038/ncomms15262] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 03/14/2017] [Indexed: 12/19/2022] Open
Abstract
NRAS and its effector BRAF are frequently mutated in melanoma. Paradoxically, CRAF but not BRAF was shown to be critical for various RAS-driven cancers, raising the question of the role of RAF proteins in NRAS-induced melanoma. Here, using conditional ablation of Raf genes in NRAS-induced mouse melanoma models, we investigate their contribution in tumour progression, from the onset of benign tumours to malignant tumour maintenance. We show that BRAF expression is required for ERK activation and nevi development, demonstrating a critical role in the early stages of NRAS-driven melanoma. After melanoma formation, single Braf or Craf ablation is not sufficient to block tumour growth, showing redundant functions for RAF kinases. Finally, proliferation of resistant cells emerging in the absence of BRAF and CRAF remains dependent on ARAF-mediated ERK activation. These results reveal specific and compensatory functions for BRAF and CRAF and highlight an addiction to RAF signalling in NRAS-driven melanoma. The melanoma-driver mutations in NRAS and BRAF are mutually exclusive but the contribution of RAF signalling downstream of NRAS remains to be clarified. Here, using mouse models, the authors show specific roles of each member of the RAF family at different stages of melanomagenesis.
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Affiliation(s)
- Coralie Dorard
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France.,Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay F-91405, France
| | - Charlène Estrada
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France.,Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay F-91405, France
| | - Céline Barbotin
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France.,Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay F-91405, France
| | - Magalie Larcher
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France.,Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay F-91405, France
| | - Alexandra Garancher
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France
| | - Jessy Leloup
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France.,Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay F-91405, France
| | - Friedrich Beermann
- Swiss Institute for Experimental Cancer Research (ISREC), Ecole Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland
| | - Manuela Baccarini
- Max F. Perutz Laboratories, Center for Molecular Biology, University of Vienna, Vienna 1030, Austria
| | - Celio Pouponnot
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France
| | - Lionel Larue
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France.,Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay F-91405, France
| | - Alain Eychène
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France.,Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay F-91405, France
| | - Sabine Druillennec
- Institut Curie, Orsay F-91405, France.,INSERM U1021, Centre Universitaire, Orsay F-91405, France.,CNRS UMR 3347, Centre Universitaire, Orsay F-91405, France.,Université Paris Sud-11, Orsay F-91405, France.,Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay F-91405, France
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52
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Jansen JM, Wartchow C, Jahnke W, Fong S, Tsang T, Pfister K, Zavorotinskaya T, Bussiere D, Cheng JM, Crawford K, Dai Y, Dove J, Fang E, Feng Y, Florent JM, Fuller J, Gossert AD, Hekmat-Nejad M, Henry C, Klopp J, Lenahan WP, Lingel A, Ma S, Meyer A, Mishina Y, Narberes J, Pardee G, Ramurthy S, Rieffel S, Stuart D, Subramanian S, Tandeske L, Widger S, Widmer A, Winterhalter A, Zaror I, Hardy S. Inhibition of prenylated KRAS in a lipid environment. PLoS One 2017; 12:e0174706. [PMID: 28384226 PMCID: PMC5383040 DOI: 10.1371/journal.pone.0174706] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 03/14/2017] [Indexed: 12/30/2022] Open
Abstract
RAS mutations lead to a constitutively active oncogenic protein that signals through multiple effector pathways. In this chemical biology study, we describe a novel coupled biochemical assay that measures activation of the effector BRAF by prenylated KRASG12V in a lipid-dependent manner. Using this assay, we discovered compounds that block biochemical and cellular functions of KRASG12V with low single-digit micromolar potency. We characterized the structural basis for inhibition using NMR methods and showed that the compounds stabilized the inactive conformation of KRASG12V. Determination of the biophysical affinity of binding using biolayer interferometry demonstrated that the potency of inhibition matches the affinity of binding only when KRAS is in its native state, namely post-translationally modified and in a lipid environment. The assays we describe here provide a first-time alignment across biochemical, biophysical, and cellular KRAS assays through incorporation of key physiological factors regulating RAS biology, namely a negatively charged lipid environment and prenylation, into the in vitro assays. These assays and the ligands we discovered are valuable tools for further study of KRAS inhibition and drug discovery.
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Affiliation(s)
- Johanna M. Jansen
- Department of Global Discovery Chemistry, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
- * E-mail:
| | - Charles Wartchow
- Department of Global Discovery Chemistry, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Wolfgang Jahnke
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Susan Fong
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Tiffany Tsang
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Keith Pfister
- Department of Global Discovery Chemistry, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Tatiana Zavorotinskaya
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Dirksen Bussiere
- Department of Global Discovery Chemistry, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Jan Marie Cheng
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Kenneth Crawford
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Yumin Dai
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Jeffrey Dove
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Eric Fang
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Yun Feng
- Department of Oncology, Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Jean-Michel Florent
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - John Fuller
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Alvar D. Gossert
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Mohammad Hekmat-Nejad
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Chrystèle Henry
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Julia Klopp
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - William P. Lenahan
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Andreas Lingel
- Department of Global Discovery Chemistry, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Sylvia Ma
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Arndt Meyer
- Department of Global Discovery Chemistry, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Yuji Mishina
- Department of Oncology, Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Jamie Narberes
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Gwynn Pardee
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Savithri Ramurthy
- Department of Global Discovery Chemistry, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Sebastien Rieffel
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Darrin Stuart
- Department of Oncology, Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, United States of America
| | - Sharadha Subramanian
- Department of Global Discovery Chemistry, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Laura Tandeske
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Stephania Widger
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Armin Widmer
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Aurelie Winterhalter
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Isabel Zaror
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
| | - Stephen Hardy
- Department of Oncology, Novartis Institutes for BioMedical Research, Emeryville, California, United States of America
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53
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Sullenberger C, Piqué D, Ogata Y, Mensa-Wilmot K. AEE788 Inhibits Basal Body Assembly and Blocks DNA Replication in the African Trypanosome. Mol Pharmacol 2017; 91:482-498. [PMID: 28246189 PMCID: PMC5399642 DOI: 10.1124/mol.116.106906] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Accepted: 02/17/2017] [Indexed: 12/15/2022] Open
Abstract
Trypanosoma brucei causes human African trypanosomiasis (HAT). The pyrrolopyrimidine AEE788 (a hit for anti-HAT drug discovery) associates with three trypanosome protein kinases. Herein we delineate the effects of AEE788 on T. brucei using chemical biology strategies. AEE788 treatment inhibits DNA replication in the kinetoplast (mitochondrial nucleoid) and nucleus. In addition, AEE788 blocks duplication of the basal body and the bilobe without affecting mitosis. Thus, AEE788 prevents entry into the S-phase of the cell division cycle. To study the kinetics of early events in trypanosome division, we employed an "AEE788 block and release" protocol to stage entry into the S-phase. A time-course of DNA synthesis (nuclear and kinetoplast DNA), duplication of organelles (basal body, bilobe, kinetoplast, nucleus), and cytokinesis was obtained. Unexpected findings include the following: 1) basal body and bilobe duplication are concurrent; 2) maturation of probasal bodies, marked by TbRP2 recruitment, is coupled with nascent basal body assembly, monitored by localization of TbSAS6 at newly forming basal bodies; and 3) kinetoplast division is observed in G2 after completion of nuclear DNA synthesis. Prolonged exposure of trypanosomes to AEE788 inhibited transferrin endocytosis, altered cell morphology, and decreased cell viability. To discover putative effectors for the pleiotropic effects of AEE788, proteome-wide changes in protein phosphorylation induced by the drug were determined. Putative effectors include an SR protein kinase, bilobe proteins, TbSAS4, TbRP2, and BILBO-1. Loss of function of one or more of these effectors can, from published literature, explain the polypharmacology of AEE788 on trypanosome biology.
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Affiliation(s)
- Catherine Sullenberger
- Department of Cellular Biology, and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia (C.S., D.P., K.M.-W.); and the Proteomics Facility, Fred Hutchinson Cancer Research Center, Seattle, Washington (Y.O.)
| | - Daniel Piqué
- Department of Cellular Biology, and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia (C.S., D.P., K.M.-W.); and the Proteomics Facility, Fred Hutchinson Cancer Research Center, Seattle, Washington (Y.O.)
| | - Yuko Ogata
- Department of Cellular Biology, and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia (C.S., D.P., K.M.-W.); and the Proteomics Facility, Fred Hutchinson Cancer Research Center, Seattle, Washington (Y.O.)
| | - Kojo Mensa-Wilmot
- Department of Cellular Biology, and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia (C.S., D.P., K.M.-W.); and the Proteomics Facility, Fred Hutchinson Cancer Research Center, Seattle, Washington (Y.O.)
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54
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Fukada T, Sakajiri H, Kuroda M, Kioka N, Sugimoto K. Fluid shear stress applied by orbital shaking induces MG-63 osteosarcoma cells to activate ERK in two phases through distinct signaling pathways. Biochem Biophys Rep 2017; 9:257-265. [PMID: 28956013 PMCID: PMC5614596 DOI: 10.1016/j.bbrep.2017.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 11/25/2016] [Accepted: 01/05/2017] [Indexed: 11/30/2022] Open
Abstract
Fluid shear stress (FSS) induces a series of biochemical responses in osteoblasts, and this “mechanoresponse” regulates their survival, proliferation and differentiation. However, the events in cells immediately after FSS application are unclear, and how biochemical signals from soluble factors modify the mechanoresponses is largely unknown. We used the orbital shaking method, instead of the frequently used parallel plate method, to examine activation of ERK and AKT by FSS for detailed tracking of its temporal transition. We found that ERK activation by orbital shaking was biphasic. The early phase was independent of Ca2+, PI3-kinase, and Rho kinase but required RAF activity. The late phase was dependent on Ca2+ but not RAF. These results suggest that the superior time-resolving capability of the orbital shaking method to separate the previously unrecognized Ca2+-independent early phase of ERK activation from the late phase. We also found that a certain combination of serum starvation and medium renewal affected ERK activation by FSS, suggesting that a soluble factor(s) may be secreted during serum starvation, which modified the phosphorylation level of ERK. These findings revealed novel aspects of the osteoblastic mechanoresponses and indicated that the orbital shaking method would be a useful, complementary alternative to the parallel plate method for certain types of study on cellular mechanoresponses. Fluid flow by orbital shaking induces biphasic activation of ERK in osteoblasts. Early-phase ERK activation is unique because of its independence of Ca2+ signaling. Serum starvation has complex effects on ERK activation by fluid flow. Orbital shaking is useful for certain types of study on cellular mechanoresponses.
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Affiliation(s)
- Takashi Fukada
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
| | - Hiroki Sakajiri
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
| | - Mito Kuroda
- Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyou-ku, Kyoto 606-8502, Japan
| | - Noriyuki Kioka
- Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyou-ku, Kyoto 606-8502, Japan
| | - Kenji Sugimoto
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
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55
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Spender LC, Ferguson GJ, Liu S, Cui C, Girotti MR, Sibbet G, Higgs EB, Shuttleworth MK, Hamilton T, Lorigan P, Weller M, Vincent DF, Sansom OJ, Frame M, Dijke PT, Marais R, Inman GJ. Mutational activation of BRAF confers sensitivity to transforming growth factor beta inhibitors in human cancer cells. Oncotarget 2016; 7:81995-82012. [PMID: 27835901 PMCID: PMC5347669 DOI: 10.18632/oncotarget.13226] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 07/18/2016] [Indexed: 12/25/2022] Open
Abstract
Recent data implicate elevated transforming growth factor-β (TGFβ) signalling in BRAF inhibitor drug-resistance mechanisms, but the potential for targeting TGFβ signalling in cases of advanced melanoma has not been investigated. We show that mutant BRAFV600E confers an intrinsic dependence on TGFβ/TGFβ receptor 1 (TGFBR1) signalling for clonogenicity of murine melanocytes. Pharmacological inhibition of the TGFBR1 blocked the clonogenicity of human mutant BRAF melanoma cells through SMAD4-independent inhibition of mitosis, and also inhibited metastasis in xenografted zebrafish. When investigating the therapeutic potential of combining inhibitors of mutant BRAF and TGFBR1, we noted that unexpectedly, low-dose PLX-4720 (a vemurafenib analogue) promoted proliferation of drug-naïve melanoma cells. Pharmacological or pharmacogenetic inhibition of TGFBR1 blocked growth promotion and phosphorylation of SRC, which is frequently associated with vemurafenib-resistance mechanisms. Importantly, vemurafenib-resistant patient derived cells retained sensitivity to TGFBR1 inhibition, suggesting that TGFBR1 could be targeted therapeutically to combat the development of vemurafenib drug-resistance.
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MESH Headings
- Animals
- Animals, Genetically Modified
- Antineoplastic Agents/pharmacology
- Benzamides/pharmacology
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Dioxoles/pharmacology
- Dose-Response Relationship, Drug
- Drug Resistance, Neoplasm/drug effects
- Drug Resistance, Neoplasm/genetics
- Humans
- Indoles/pharmacology
- Melanocytes/drug effects
- Melanocytes/enzymology
- Melanocytes/pathology
- Melanoma/drug therapy
- Melanoma/enzymology
- Melanoma/genetics
- Melanoma/pathology
- Mice, Nude
- Mitosis/drug effects
- Mutation
- Protein Kinase Inhibitors/pharmacology
- Protein Serine-Threonine Kinases/antagonists & inhibitors
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Proto-Oncogene Proteins B-raf/antagonists & inhibitors
- Proto-Oncogene Proteins B-raf/genetics
- Proto-Oncogene Proteins B-raf/metabolism
- RNA Interference
- Receptor, Transforming Growth Factor-beta Type I
- Receptors, Transforming Growth Factor beta/antagonists & inhibitors
- Receptors, Transforming Growth Factor beta/genetics
- Receptors, Transforming Growth Factor beta/metabolism
- Signal Transduction/drug effects
- Skin Neoplasms/drug therapy
- Skin Neoplasms/enzymology
- Skin Neoplasms/genetics
- Skin Neoplasms/pathology
- Smad4 Protein/genetics
- Smad4 Protein/metabolism
- Sulfonamides/pharmacology
- Time Factors
- Transfection
- Transforming Growth Factor beta1/pharmacology
- Vemurafenib
- Xenograft Model Antitumor Assays
- Zebrafish
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Affiliation(s)
- Lindsay C. Spender
- Growth Factor Signalling Laboratory, The Beatson Institute for Cancer Research, Bearsden, Glasgow, United Kingdom
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee, United Kingdom
| | - G. John Ferguson
- Growth Factor Signalling Laboratory, The Beatson Institute for Cancer Research, Bearsden, Glasgow, United Kingdom
- Department of Respiratory, Inflammation and Autoimmunity Research, MedImmune Limited, Cambridge, United Kingdom
| | - Sijia Liu
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands, Leiden University Medical Center, Einthovenweg, Leiden, Netherlands
| | - Chao Cui
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands, Leiden University Medical Center, Einthovenweg, Leiden, Netherlands
| | - Maria Romina Girotti
- Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Withington, Manchester, United Kingdom
| | - Gary Sibbet
- Growth Factor Signalling Laboratory, The Beatson Institute for Cancer Research, Bearsden, Glasgow, United Kingdom
| | - Ellen B. Higgs
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee, United Kingdom
| | - Morven K. Shuttleworth
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee, United Kingdom
| | - Tom Hamilton
- Biological Services, The Beatson Institute for Cancer Research, Bearsden, Glasgow, United Kingdom
| | - Paul Lorigan
- The University of Manchester, The Christie NHS Foundation Trust, Manchester, United Kingdom
| | - Michael Weller
- Department of Neurology, University Hospital Zurich, Frauenklinikstrasse, Zurich, Switzerland
| | - David F. Vincent
- Colorectal Cancer and Wnt Signalling, The Beatson Institute for Cancer Research, Bearsden, Glasgow, United Kingdom
| | - Owen J. Sansom
- Colorectal Cancer and Wnt Signalling, The Beatson Institute for Cancer Research, Bearsden, Glasgow, United Kingdom
| | - Margaret Frame
- The Institute of Genetics and Molecular Medicine, Edinburgh Cancer Research Centre, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Peter ten Dijke
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands, Leiden University Medical Center, Einthovenweg, Leiden, Netherlands
| | - Richard Marais
- Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Withington, Manchester, United Kingdom
| | - Gareth J. Inman
- Growth Factor Signalling Laboratory, The Beatson Institute for Cancer Research, Bearsden, Glasgow, United Kingdom
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee, United Kingdom
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56
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Karoulia Z, Wu Y, Ahmed TA, Xin Q, Bollard J, Krepler C, Wu X, Zhang C, Bollag G, Herlyn M, Fagin JA, Lujambio A, Gavathiotis E, Poulikakos PI. An Integrated Model of RAF Inhibitor Action Predicts Inhibitor Activity against Oncogenic BRAF Signaling. Cancer Cell 2016; 30:485-498. [PMID: 27523909 PMCID: PMC5021590 DOI: 10.1016/j.ccell.2016.06.024] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 05/10/2016] [Accepted: 06/29/2016] [Indexed: 12/19/2022]
Abstract
The complex biochemical effects of RAF inhibitors account for both the effectiveness and mechanisms of resistance to these drugs, but a unified mechanistic model has been lacking. Here we show that RAF inhibitors exert their effects via two distinct allosteric mechanisms. Drug resistance due to dimerization is determined by the position of the αC helix stabilized by inhibitor, whereas inhibitor-induced RAF priming and dimerization are the result of inhibitor-induced formation of the RAF/RAS-GTP complex. The biochemical effect of RAF inhibitor in cells is the combined outcome of the two mechanisms. Therapeutic strategies including αC-helix-IN inhibitors are more effective in multiple mutant BRAF-driven tumor models, including colorectal and thyroid BRAF(V600E) cancers, in which first-generation RAF inhibitors have been ineffective.
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Affiliation(s)
- Zoi Karoulia
- Department of Oncological Sciences, Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yang Wu
- Department of Biochemistry, Department of Medicine, Albert Einstein Cancer Center, Wilf Family Cardiovascular Research Institute, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Tamer A Ahmed
- Department of Oncological Sciences, Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Qisheng Xin
- Department of Biochemistry, Department of Medicine, Albert Einstein Cancer Center, Wilf Family Cardiovascular Research Institute, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Julien Bollard
- Department of Oncological Sciences, Liver Cancer program, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Clemens Krepler
- Molecular and Cellular Oncogenesis Program, Tumor Microenvironment and Metastasis Program, and Melanoma Research Center, The Wistar Institute, Philadelphia, PA 19014, USA
| | - Xuewei Wu
- Department of Oncological Sciences, Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | | | | | - Meenhard Herlyn
- Molecular and Cellular Oncogenesis Program, Tumor Microenvironment and Metastasis Program, and Melanoma Research Center, The Wistar Institute, Philadelphia, PA 19014, USA
| | - James A Fagin
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Amaia Lujambio
- Department of Oncological Sciences, Liver Cancer program, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Evripidis Gavathiotis
- Department of Biochemistry, Department of Medicine, Albert Einstein Cancer Center, Wilf Family Cardiovascular Research Institute, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Poulikos I Poulikakos
- Department of Oncological Sciences, Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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57
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Noeparast A, Teugels E, Giron P, Verschelden G, De Brakeleer S, Decoster L, De Grève J. Non-V600 BRAF mutations recurrently found in lung cancer predict sensitivity to the combination of Trametinib and Dabrafenib. Oncotarget 2016; 8:60094-60108. [PMID: 28947956 PMCID: PMC5601124 DOI: 10.18632/oncotarget.11635] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 06/09/2016] [Indexed: 12/12/2022] Open
Abstract
Approximately half of BRAF-mutated Non-small cell lung cancers (NSCLCs) harbor a non-V600 BRAF mutation, accounting for ∼40,000 annual deaths worldwide. Recent studies have revealed the benefits of combined targeted therapy with a RAF-inhibitor (Dabrafenib) and a MEK-inhibitor (Trametinib) in treating V600 BRAF mutant cancers, including NSCLC. In contrast, sensitivity of non-V600 BRAF mutations to these inhibitors is not documented. Non-V600 mutations can either increase or impair BRAF kinase activity. However, impaired BRAF kinases can still activate the ERK pathway in a CRAF-dependent manner. Herein, beyond describing a cohort of BRAF mutant NSCLC patients and functionally analyzing 13 tumor-derived BRAF mutations, we demonstrate that both types of non-V600 BRAF mutations can be sensitive to clinically relevant doses of Dabrafenib and Trametinib in HEK293T cells, in lung epithelial cellular model (BEAS-2B) and in human cancer cell lines harboring non-V600 BRAF mutations. ERK activity induced by both types of these mutations is further reduced by combinatorial drug treatment. Moreover, the combination leads to more prolonged ERK inhibition and has anti-proliferative and pro-apoptotic effects in cells harboring both types of non-V600 BRAF mutations. This study provides a basis for the clinical exploration of non-V600 BRAF mutant lung cancers upon treatment with Trametinib and Dabrafenib.
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Affiliation(s)
- Amir Noeparast
- Laboratory of Molecular Oncology and Department of Medical Oncology, Oncologisch Centrum, UZ Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Erik Teugels
- Laboratory of Molecular Oncology and Department of Medical Oncology, Oncologisch Centrum, UZ Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Philippe Giron
- Laboratory of Molecular Oncology and Department of Medical Oncology, Oncologisch Centrum, UZ Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Gil Verschelden
- Laboratory of Molecular Oncology and Department of Medical Oncology, Oncologisch Centrum, UZ Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Sylvia De Brakeleer
- Laboratory of Molecular Oncology and Department of Medical Oncology, Oncologisch Centrum, UZ Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Lore Decoster
- Laboratory of Molecular Oncology and Department of Medical Oncology, Oncologisch Centrum, UZ Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Jacques De Grève
- Laboratory of Molecular Oncology and Department of Medical Oncology, Oncologisch Centrum, UZ Brussel, Vrije Universiteit Brussel, Brussels, Belgium
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58
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Cammareri P, Rose AM, Vincent DF, Wang J, Nagano A, Libertini S, Ridgway RA, Athineos D, Coates PJ, McHugh A, Pourreyron C, Dayal JHS, Larsson J, Weidlich S, Spender LC, Sapkota GP, Purdie KJ, Proby CM, Harwood CA, Leigh IM, Clevers H, Barker N, Karlsson S, Pritchard C, Marais R, Chelala C, South AP, Sansom OJ, Inman GJ. Inactivation of TGFβ receptors in stem cells drives cutaneous squamous cell carcinoma. Nat Commun 2016; 7:12493. [PMID: 27558455 PMCID: PMC5007296 DOI: 10.1038/ncomms12493] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 07/07/2016] [Indexed: 01/03/2023] Open
Abstract
Melanoma patients treated with oncogenic BRAF inhibitors can develop cutaneous squamous cell carcinoma (cSCC) within weeks of treatment, driven by paradoxical RAS/RAF/MAPK pathway activation. Here we identify frequent TGFBR1 and TGFBR2 mutations in human vemurafenib-induced skin lesions and in sporadic cSCC. Functional analysis reveals these mutations ablate canonical TGFβ Smad signalling, which is localized to bulge stem cells in both normal human and murine skin. MAPK pathway hyperactivation (through Braf(V600E) or Kras(G12D) knockin) and TGFβ signalling ablation (through Tgfbr1 deletion) in LGR5(+ve) stem cells enables rapid cSCC development in the mouse. Mutation of Tp53 (which is commonly mutated in sporadic cSCC) coupled with Tgfbr1 deletion in LGR5(+ve) cells also results in cSCC development. These findings indicate that LGR5(+ve) stem cells may act as cells of origin for cSCC, and that RAS/RAF/MAPK pathway hyperactivation or Tp53 mutation, coupled with loss of TGFβ signalling, are driving events of skin tumorigenesis.
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MESH Headings
- Animals
- Antineoplastic Agents/adverse effects
- Biopsy
- Carcinogenesis/genetics
- Carcinoma, Squamous Cell/chemically induced
- Carcinoma, Squamous Cell/genetics
- Carcinoma, Squamous Cell/pathology
- Cell Line, Tumor
- DNA Mutational Analysis/methods
- Female
- Humans
- Indoles/adverse effects
- Male
- Melanoma/drug therapy
- Mice
- Mice, Inbred Strains
- Mutation
- Neoplasms, Experimental/chemically induced
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/pathology
- Protein Serine-Threonine Kinases/genetics
- Proto-Oncogene Proteins B-raf/antagonists & inhibitors
- Proto-Oncogene Proteins B-raf/genetics
- Proto-Oncogene Proteins B-raf/metabolism
- Proto-Oncogene Proteins p21(ras)/genetics
- Proto-Oncogene Proteins p21(ras)/metabolism
- Receptor, Transforming Growth Factor-beta Type I
- Receptor, Transforming Growth Factor-beta Type II
- Receptors, Transforming Growth Factor beta/genetics
- Signal Transduction/drug effects
- Skin Neoplasms/chemically induced
- Skin Neoplasms/genetics
- Skin Neoplasms/pathology
- Stem Cells
- Sulfonamides/adverse effects
- Transforming Growth Factor beta/metabolism
- Tumor Suppressor Protein p53/genetics
- Vemurafenib
- Exome Sequencing
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Affiliation(s)
- Patrizia Cammareri
- Wnt Signaling and Colorectal Cancer Group, Cancer Research UK Beatson Institute, Institute of Cancer Sciences, Glasgow University, Garscube Estate, Switichback Road, Glasgow G61 1BD, UK
| | - Aidan M. Rose
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
| | - David F. Vincent
- Wnt Signaling and Colorectal Cancer Group, Cancer Research UK Beatson Institute, Institute of Cancer Sciences, Glasgow University, Garscube Estate, Switichback Road, Glasgow G61 1BD, UK
| | - Jun Wang
- Bioinformatics Unit, Barts Cancer Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - Ai Nagano
- Bioinformatics Unit, Barts Cancer Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - Silvana Libertini
- Wnt Signaling and Colorectal Cancer Group, Cancer Research UK Beatson Institute, Institute of Cancer Sciences, Glasgow University, Garscube Estate, Switichback Road, Glasgow G61 1BD, UK
| | - Rachel A. Ridgway
- Wnt Signaling and Colorectal Cancer Group, Cancer Research UK Beatson Institute, Institute of Cancer Sciences, Glasgow University, Garscube Estate, Switichback Road, Glasgow G61 1BD, UK
| | - Dimitris Athineos
- Wnt Signaling and Colorectal Cancer Group, Cancer Research UK Beatson Institute, Institute of Cancer Sciences, Glasgow University, Garscube Estate, Switichback Road, Glasgow G61 1BD, UK
| | - Philip J. Coates
- Tayside Tissue Bank, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
| | - Angela McHugh
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
| | - Celine Pourreyron
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
| | - Jasbani H. S. Dayal
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
| | - Jonas Larsson
- Molecular Medicine and Gene Therapy, Lund Strategic Center for Stem Cell Biology, Lund University, Lund 221 00, Sweden
| | - Simone Weidlich
- MRC Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Lindsay C. Spender
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
| | - Gopal P. Sapkota
- MRC Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Karin J. Purdie
- Centre for Cutaneous Research, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - Charlotte M. Proby
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
| | - Catherine A. Harwood
- Centre for Cutaneous Research, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - Irene M. Leigh
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
- Centre for Cutaneous Research, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - Hans Clevers
- Hubrecht Institute, Utrecht 3584 CT, The Netherlands
| | - Nick Barker
- Institute of Medical Biology, Immunos 138648, Singapore
| | - Stefan Karlsson
- Molecular Medicine and Gene Therapy, Lund Strategic Center for Stem Cell Biology, Lund University, Lund 221 00, Sweden
| | - Catrin Pritchard
- Department of Biochemistry, University of Leicester, Leicester LE1 9HN, UK
| | - Richard Marais
- The Paterson Institute for Cancer Research, Manchester M20 4BX, UK
| | - Claude Chelala
- Bioinformatics Unit, Barts Cancer Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - Andrew P. South
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
- Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
| | - Owen J. Sansom
- Wnt Signaling and Colorectal Cancer Group, Cancer Research UK Beatson Institute, Institute of Cancer Sciences, Glasgow University, Garscube Estate, Switichback Road, Glasgow G61 1BD, UK
| | - Gareth J. Inman
- Division of Cancer Research, School of Medicine, University of Dundee, Dundee DD1 9SY, UK
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59
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Cutaneous wound healing through paradoxical MAPK activation by BRAF inhibitors. Nat Commun 2016; 7:12348. [PMID: 27476449 PMCID: PMC4974650 DOI: 10.1038/ncomms12348] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 06/23/2016] [Indexed: 01/07/2023] Open
Abstract
BRAF inhibitors are highly effective therapies for the treatment of BRAFV600-mutated melanoma, with the main toxicity being a variety of hyperproliferative skin conditions due to paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway in BRAF wild-type cells. Most of these hyperproliferative skin changes improve when a MEK inhibitor is co-administered, as it blocks paradoxical MAPK activation. Here we show how the BRAF inhibitor vemurafenib accelerates skin wound healing by inducing the proliferation and migration of human keratinocytes through extracellular signal-regulated kinase (ERK) phosphorylation and cell cycle progression. Topical treatment with vemurafenib in two wound-healing mice models accelerates cutaneous wound healing through paradoxical MAPK activation; addition of a mitogen-activated protein kinase kinase (MEK) inhibitor reverses the benefit of vemurafenib-accelerated wound healing. The same dosing regimen of topical BRAF inhibitor does not increase the incidence of cutaneous squamous cell carcinomas in mice. Therefore, topical BRAF inhibitors may have clinical applications in accelerating the healing of skin wounds. BRAF inhibitors often show skin-hyperproliferative side effects in melanoma patients. Here, the authors demonstrate that BRAF inhibitors can be used to enhance skin wound healing through the MAPK- ERK pathway activation that positively regulates the proliferation of keratinocytes.
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60
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Dernayka L, Rauch N, Jarboui MA, Zebisch A, Texier Y, Horn N, Romano D, Gloeckner CJ, Kriegsheim AV, Ueffing M, Kolch W, Boldt K. Autophosphorylation on S614 inhibits the activity and the transforming potential of BRAF. Cell Signal 2016; 28:1432-1439. [PMID: 27345148 DOI: 10.1016/j.cellsig.2016.06.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 06/09/2016] [Accepted: 06/18/2016] [Indexed: 12/25/2022]
Abstract
The BRAF proto-oncogene serine/threonine-protein kinase, known as BRAF, belongs to the RAF kinase family. It regulates the MAPK/ERK signalling pathway affecting several cellular processes such as growth, survival, differentiation, and cellular transformation. BRAF is mutated in ~8% of all human cancers with the V600E mutation constituting ~90% of mutations. Here, we have used quantitative mass spectrometry to map and compare phosphorylation site patterns between BRAF and BRAF V600E. We identified sites that are shared as well as several quantitative differences in phosphorylation abundance. The highest difference is phosphorylation of S614 in the activation loop which is ~5fold enhanced in BRAF V600E. Mutation of S614 increases the kinase activity of both BRAF and BRAF V600E and the transforming ability of BRAF V600E. The phosphorylation of S614 is mitogen inducible and the result of autophosphorylation. These data suggest that phosphorylation at this site is inhibitory, and part of the physiological shut-down mechanism of BRAF signalling.
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Affiliation(s)
- Layal Dernayka
- Medical Proteome Center, Division for Experimental Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany
| | - Nora Rauch
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland
| | - Mohamed-Ali Jarboui
- Medical Proteome Center, Division for Experimental Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany
| | - Armin Zebisch
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland
| | - Yves Texier
- Medical Proteome Center, Division for Experimental Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany
| | - Nicola Horn
- Medical Proteome Center, Division for Experimental Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany
| | - David Romano
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland
| | - Christian Johannes Gloeckner
- Medical Proteome Center, Division for Experimental Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany; Deutsches Zentrum für Neurodegenerative Erkrankungen e. V., Otfried-Müller Strasse 23, 72076 Tübingen, Germany
| | - Alex von Kriegsheim
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland
| | - Marius Ueffing
- Medical Proteome Center, Division for Experimental Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany
| | - Walter Kolch
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland; Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland; School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland.
| | - Karsten Boldt
- Medical Proteome Center, Division for Experimental Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany.
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61
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Somatic mutations in histiocytic sarcoma identified by next generation sequencing. Virchows Arch 2016; 469:233-41. [DOI: 10.1007/s00428-016-1965-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 04/24/2016] [Accepted: 05/17/2016] [Indexed: 01/04/2023]
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62
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Optogenetically controlled RAF to characterize BRAF and CRAF protein kinase inhibitors. Sci Rep 2016; 6:23713. [PMID: 27025703 PMCID: PMC4812324 DOI: 10.1038/srep23713] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 03/14/2016] [Indexed: 12/19/2022] Open
Abstract
Here, we applied optoRAF, an optogenetic tool for light-controlled clustering and activation of RAF proteins that mimics the natural occurring RAS-mediated dimerization. This versatile tool allows studying the effect on BRAF and CRAF homodimer- as well as heterodimer-induced RAF signaling. Vemurafenib and dabrafenib are two clinically approved inhibitors for BRAF that efficiently suppress the kinase activity of oncogenic BRAF (V600E). However in wild-type BRAF expressing cells, BRAF inhibitors can exert paradoxical activation of wild-type CRAF. Using optoRAF, vemurafenib was identified as paradoxical activator of BRAF and CRAF homo- and heterodimers. Dabrafenib enhanced activity of light-stimulated CRAF at low dose and inhibited CRAF signaling at high dose. Moreover, dabrafenib increased the protein level of CRAF proteins but not of BRAF proteins. Increased CRAF levels correlate with elevated RAF signaling in a dabrafenib-dependent manner, independent of light activation.
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63
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Zhang J, Lu B, Liu D, Shen R, Yan Y, Yang L, Zhang M, Zhang L, Cao G, Cao H, Fu B, Gong A, Sun Q, Wan H, Zhang L, Tao W, Cao J. EBI-907, a novel BRAF(V600E) inhibitor, has potent oral anti-tumor activity and a broad kinase selectivity profile. Cancer Biol Ther 2016; 17:199-207. [PMID: 26810733 DOI: 10.1080/15384047.2016.1139231] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The oncogenic mutation of BRAF(V600E) has been found in approximately 8% of all human cancers, including more than 60% of melanoma and 10% of colorectal cancers. The clinical proof of concept in treating BRAF(V600E)-driving melanoma patients with the BRAF inhibitors has been well established. We have sought to identify and develop novel BRAF(V600E) inhibitors with more favorable profiles. Our chemistry effort has led to the discovery of EBI-907 as a novel BRAF(V600E) inhibitor with potent anti-tumor activity in vitro and in vivo. In a LanthaScreen BRAF(V600E) kinase assay, EBI-907 showed an IC50 of 4.8 nM, which is >10 -fold more potent than Vemurafenib (IC50 = 58.5 nM). In addition, EBI-907 showed a broader kinase selectivity profile, with potent activity against a number of important oncogenic kinases including FGFR1-3, RET, c-Kit, and PDGFRb. Concomitant with such properties, EBI-907 exhibits potent and selective cytotoxicity against a broader range of BRAF(V600E)-dependent cell lines including certain colorectal cancer cell lines with innate resistance to Vemurafenib. In BRAF(V600E)-dependent human Colo-205 and A375 tumor xenograft mouse models, EBI-907 caused a marked tumor regression in a dose-dependent manner, with superior efficacy to Vemurafenib. Our results also showed that combination with EGFR or MEK inhibitor enhanced the potency of EBI-907 in cell lines with innate or acquired resistance to BRAF inhibition alone. Our findings present EBI-907 as a potent and promising BRAF inhibitor, which might be useful in broader indications.
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Affiliation(s)
- Jiayin Zhang
- a Eternity Bioscience Inc , 2005 EastPark Blvd, Cranbury , USA
| | - Biao Lu
- b Shanghai Hengrui Pharmaceutical Co. LTD , 279 Wenjing Rd, Minhang Hi-Tech Zone, Shanghai , China
| | - Dong Liu
- a Eternity Bioscience Inc , 2005 EastPark Blvd, Cranbury , USA
| | - Ru Shen
- a Eternity Bioscience Inc , 2005 EastPark Blvd, Cranbury , USA
| | - Yinfa Yan
- a Eternity Bioscience Inc , 2005 EastPark Blvd, Cranbury , USA
| | - Liuqing Yang
- a Eternity Bioscience Inc , 2005 EastPark Blvd, Cranbury , USA
| | - Minsheng Zhang
- a Eternity Bioscience Inc , 2005 EastPark Blvd, Cranbury , USA
| | - Lei Zhang
- b Shanghai Hengrui Pharmaceutical Co. LTD , 279 Wenjing Rd, Minhang Hi-Tech Zone, Shanghai , China
| | - Guoqing Cao
- b Shanghai Hengrui Pharmaceutical Co. LTD , 279 Wenjing Rd, Minhang Hi-Tech Zone, Shanghai , China
| | - Hu Cao
- b Shanghai Hengrui Pharmaceutical Co. LTD , 279 Wenjing Rd, Minhang Hi-Tech Zone, Shanghai , China
| | - Beibei Fu
- b Shanghai Hengrui Pharmaceutical Co. LTD , 279 Wenjing Rd, Minhang Hi-Tech Zone, Shanghai , China
| | - Aishen Gong
- b Shanghai Hengrui Pharmaceutical Co. LTD , 279 Wenjing Rd, Minhang Hi-Tech Zone, Shanghai , China
| | - Qiming Sun
- b Shanghai Hengrui Pharmaceutical Co. LTD , 279 Wenjing Rd, Minhang Hi-Tech Zone, Shanghai , China
| | - Hong Wan
- b Shanghai Hengrui Pharmaceutical Co. LTD , 279 Wenjing Rd, Minhang Hi-Tech Zone, Shanghai , China
| | - Lianshan Zhang
- c National Engineering and Research Center for Targeted Drugs, Jiangsu Hengrui Medicine Co., LTD , 7 Kunlun Shan Road, Lianyungang Economic and Technology Development Zone, Jiangsu , China
| | - Weikang Tao
- b Shanghai Hengrui Pharmaceutical Co. LTD , 279 Wenjing Rd, Minhang Hi-Tech Zone, Shanghai , China
| | - Jingsong Cao
- a Eternity Bioscience Inc , 2005 EastPark Blvd, Cranbury , USA
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64
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Maik-Rachline G, Seger R. The ERK cascade inhibitors: Towards overcoming resistance. Drug Resist Updat 2016; 25:1-12. [PMID: 27155372 DOI: 10.1016/j.drup.2015.12.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 12/22/2015] [Accepted: 12/25/2015] [Indexed: 12/24/2022]
Abstract
The RAS-ERK pathway plays a major regulatory role in various cellular processes. This pathway is hyperactivated and takes an active part in the malignant transformation of more than 85% of cancers. The hyperactivation is mainly due to oncogenic activating mutations in the pathway's components RAS, RAF and MEK, but also due to indirect mechanisms in cells transformed by other oncogenes. Various inhibitors targeting the different tiers of the cascade have been successfully developed and clinically approved, while some are still undergoing preclinical and clinical evaluation. Treatments with the clinically approved RAF and MEK inhibitors have substantially improved the clinical outcome of metastatic mutated-BRAF melanoma. However, the rapid emergence of drug resistance of initially responsive cancers and limited efficacy towards other cancers has led to only marginal patient benefit. Deciphering the molecular mechanisms underlying intrinsic or acquired resistance is a necessity in order to enhance the treatment efficacy of ERK-addicted cancers. Therefore, many studies in the past 5 years embarked on this campaign, revealing several resistance mechanisms. These include, expression of drug-resistant RAF isoforms, molecular or genetic alterations of active downstream components, overexpression of upstream components of the cascade that can reactivate ERK and other survival-related pathways. The understanding of these molecular resistance mechanisms led to further development of drugs that can overcome drug resistance, including our own effort aiming to prevent the nuclear translocation of ERK without affecting its activation. In this review we will focus on the mechanisms underlying drug resistance and efforts to develop activity-independent, more efficacious, antitumor drugs.
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Affiliation(s)
- Galia Maik-Rachline
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot 7610001, Israel.
| | - Rony Seger
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot 7610001, Israel
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65
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Fishbein GA, Grimes BS, Xian RR, Lee JM, Barjaktarevic I, Xu H. Primary salivary duct carcinoma of the lung, mucin-rich variant. Hum Pathol 2016; 47:150-6. [DOI: 10.1016/j.humpath.2015.09.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Revised: 08/24/2015] [Accepted: 09/02/2015] [Indexed: 10/23/2022]
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66
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Köhler M, Röring M, Schorch B, Heilmann K, Stickel N, Fiala GJ, Schmitt LC, Braun S, Ehrenfeld S, Uhl FM, Kaltenbacher T, Weinberg F, Herzog S, Zeiser R, Schamel WW, Jumaa H, Brummer T. Activation loop phosphorylation regulates B-Raf in vivo and transformation by B-Raf mutants. EMBO J 2015; 35:143-61. [PMID: 26657898 DOI: 10.15252/embj.201592097] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 10/28/2015] [Indexed: 12/19/2022] Open
Abstract
Despite being mutated in cancer and RASopathies, the role of the activation segment (AS) has not been addressed for B-Raf signaling in vivo. Here, we generated a conditional knock-in mouse allowing the expression of the B-Raf(AVKA) mutant in which the AS phosphoacceptor sites T599 and S602 are replaced by alanine residues. Surprisingly, despite producing a kinase-impaired protein, the Braf(AVKA) allele does not phenocopy the lethality of Braf-knockout or paradoxically acting knock-in alleles. However, Braf(AVKA) mice display abnormalities in the hematopoietic system, a distinct facial morphology, reduced ERK pathway activity in the brain, and an abnormal gait. This phenotype suggests that maximum B-Raf activity is required for the proper development, function, and maintenance of certain cell populations. By establishing conditional murine embryonic fibroblast cultures, we further show that MEK/ERK phosphorylation and the immediate early gene response toward growth factors are impaired in the presence of B-Raf(AVKA). Importantly, alanine substitution of T599/S602 impairs the transformation potential of oncogenic non-V600E B-Raf mutants and a fusion protein, suggesting that blocking their phosphorylation could represent an alternative strategy to ATP-competitive inhibitors.
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Affiliation(s)
- Martin Köhler
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University (ALU), Freiburg, Germany Centre for Biological Systems Analysis ZBSA, ALU, Freiburg, Germany Spemann Graduate School for Biology and Medicine, ALU, Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany
| | - Michael Röring
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University (ALU), Freiburg, Germany Centre for Biological Systems Analysis ZBSA, ALU, Freiburg, Germany Spemann Graduate School for Biology and Medicine, ALU, Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany
| | - Björn Schorch
- Centre for Biological Systems Analysis ZBSA, ALU, Freiburg, Germany Spemann Graduate School for Biology and Medicine, ALU, Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany
| | - Katharina Heilmann
- Centre for Biological Systems Analysis ZBSA, ALU, Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany
| | - Natalie Stickel
- Spemann Graduate School for Biology and Medicine, ALU, Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany Department of Hematology and Oncology, University Medical Center ALU, Freiburg, Germany
| | - Gina J Fiala
- Spemann Graduate School for Biology and Medicine, ALU, Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany Centre for Biological Signalling Studies BIOSS, ALU, Freiburg, Germany Department of Molecular Immunology, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Lisa C Schmitt
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University (ALU), Freiburg, Germany Centre for Biological Systems Analysis ZBSA, ALU, Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany
| | - Sandra Braun
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University (ALU), Freiburg, Germany Centre for Biological Systems Analysis ZBSA, ALU, Freiburg, Germany Centre for Biological Signalling Studies BIOSS, ALU, Freiburg, Germany
| | - Sophia Ehrenfeld
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University (ALU), Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany
| | - Franziska M Uhl
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University (ALU), Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany
| | - Thorsten Kaltenbacher
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University (ALU), Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany
| | - Florian Weinberg
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University (ALU), Freiburg, Germany Centre for Biological Systems Analysis ZBSA, ALU, Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany
| | - Sebastian Herzog
- Centre for Biological Systems Analysis ZBSA, ALU, Freiburg, Germany Centre for Biological Signalling Studies BIOSS, ALU, Freiburg, Germany Department of Molecular Immunology, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Robert Zeiser
- Department of Hematology and Oncology, University Medical Center ALU, Freiburg, Germany Centre for Biological Signalling Studies BIOSS, ALU, Freiburg, Germany Comprehensive Cancer Centre, Freiburg, Germany German Consortium for Translational Cancer Research DKTK, Standort Freiburg, Germany
| | - Wolfgang W Schamel
- Centre for Biological Signalling Studies BIOSS, ALU, Freiburg, Germany Department of Molecular Immunology, Faculty of Biology, University of Freiburg, Freiburg, Germany Center for Chronic Immunodeficiency CCI, University Medical Center, Freiburg, Germany
| | - Hassan Jumaa
- Centre for Biological Signalling Studies BIOSS, ALU, Freiburg, Germany Department of Molecular Immunology, Faculty of Biology, University of Freiburg, Freiburg, Germany Institute of Immunology, University Hospital Ulm, Ulm, Germany
| | - Tilman Brummer
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University (ALU), Freiburg, Germany Centre for Biological Systems Analysis ZBSA, ALU, Freiburg, Germany Faculty of Biology, ALU, Freiburg, Germany Centre for Biological Signalling Studies BIOSS, ALU, Freiburg, Germany Comprehensive Cancer Centre, Freiburg, Germany German Consortium for Translational Cancer Research DKTK, Standort Freiburg, Germany
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67
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Caunt CJ, Sale MJ, Smith PD, Cook SJ. MEK1 and MEK2 inhibitors and cancer therapy: the long and winding road. Nat Rev Cancer 2015; 15:577-92. [PMID: 26399658 DOI: 10.1038/nrc4000] [Citation(s) in RCA: 409] [Impact Index Per Article: 45.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The role of the ERK signalling pathway in cancer is thought to be most prominent in tumours in which mutations in the receptor tyrosine kinases RAS, BRAF, CRAF, MEK1 or MEK2 drive growth factor-independent ERK1 and ERK2 activation and thence inappropriate cell proliferation and survival. New drugs that inhibit RAF or MEK1 and MEK2 have recently been approved or are currently undergoing late-stage clinical evaluation. In this Review, we consider the ERK pathway, focusing particularly on the role of MEK1 and MEK2, the 'gatekeepers' of ERK1/2 activity. We discuss their validation as drug targets, the merits of targeting MEK1 and MEK2 versus BRAF and the mechanisms of action of different inhibitors of MEK1 and MEK2. We also consider how some of the systems-level properties (intrapathway regulatory loops and wider signalling network connections) of the ERK pathway present a challenge for the success of MEK1 and MEK2 inhibitors, discuss mechanisms of resistance to these inhibitors, and review their clinical progress.
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Affiliation(s)
- Christopher J Caunt
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK
| | - Matthew J Sale
- Signalling Laboratory, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Paul D Smith
- AstraZeneca, Oncology iMed, Cancer Biosciences, Cancer Research UK, Li Ka Shing Centre, Cambridge Institute, Robinson Way, Cambridge CB2 0RE, UK
| | - Simon J Cook
- Signalling Laboratory, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
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68
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Peng SB, Henry JR, Kaufman MD, Lu WP, Smith BD, Vogeti S, Rutkoski TJ, Wise S, Chun L, Zhang Y, Van Horn RD, Yin T, Zhang X, Yadav V, Chen SH, Gong X, Ma X, Webster Y, Buchanan S, Mochalkin I, Huber L, Kays L, Donoho GP, Walgren J, McCann D, Patel P, Conti I, Plowman GD, Starling JJ, Flynn DL. Inhibition of RAF Isoforms and Active Dimers by LY3009120 Leads to Anti-tumor Activities in RAS or BRAF Mutant Cancers. Cancer Cell 2015; 28:384-98. [PMID: 26343583 DOI: 10.1016/j.ccell.2015.08.002] [Citation(s) in RCA: 220] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 06/29/2015] [Accepted: 08/03/2015] [Indexed: 12/19/2022]
Abstract
LY3009120 is a pan-RAF and RAF dimer inhibitor that inhibits all RAF isoforms and occupies both protomers in RAF dimers. Biochemical and cellular analyses revealed that LY3009120 inhibits ARAF, BRAF, and CRAF isoforms with similar affinity, while vemurafenib or dabrafenib have little or modest CRAF activity compared to their BRAF activities. LY3009120 induces BRAF-CRAF dimerization but inhibits the phosphorylation of downstream MEK and ERK, suggesting that it effectively inhibits the kinase activity of BRAF-CRAF heterodimers. Further analyses demonstrated that LY3009120 also inhibits various forms of RAF dimers including BRAF or CRAF homodimers. Due to these unique properties, LY3009120 demonstrates minimal paradoxical activation, inhibits MEK1/2 phosphorylation, and exhibits anti-tumor activities across multiple models carrying KRAS, NRAS, or BRAF mutation.
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Affiliation(s)
| | | | | | - Wei-Ping Lu
- Deciphera Pharmaceuticals, LLC, Lawrence, KS 66044, USA
| | - Bryan D Smith
- Deciphera Pharmaceuticals, LLC, Lawrence, KS 66044, USA
| | - Subha Vogeti
- Deciphera Pharmaceuticals, LLC, Lawrence, KS 66044, USA
| | | | - Scott Wise
- Deciphera Pharmaceuticals, LLC, Lawrence, KS 66044, USA
| | - Lawrence Chun
- Emerald Biostructures, Bainbridge Island, WA 98110, USA
| | - Youyan Zhang
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | | | - Tinggui Yin
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Xiaoyi Zhang
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Vipin Yadav
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | | | - Xueqian Gong
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Xiwen Ma
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Yue Webster
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | | | | | | | - Lisa Kays
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | | | | | - Denis McCann
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Phenil Patel
- Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Ilaria Conti
- Eli Lilly and Company, Indianapolis, IN 46285, USA
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69
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Whittaker SR, Cowley GS, Wagner S, Luo F, Root DE, Garraway LA. Combined Pan-RAF and MEK Inhibition Overcomes Multiple Resistance Mechanisms to Selective RAF Inhibitors. Mol Cancer Ther 2015; 14:2700-11. [PMID: 26351322 DOI: 10.1158/1535-7163.mct-15-0136-t] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 08/30/2015] [Indexed: 12/19/2022]
Abstract
RAF and MEK inhibitors are effective in BRAF-mutant melanoma but not in BRAF-mutant colorectal cancer. To gain additional insights into this difference, we performed a genome-scale pooled shRNA enhancer screen in a BRAF-mutant, RAF inhibitor-resistant colorectal cancer cell line exposed to the selective RAF inhibitor PLX4720. We identified multiple genes along the receptor tyrosine kinase (RTK)/mitogen-activated protein kinase (MAPK) signaling axis that, when suppressed, either genetically or pharmacologically, sensitized cells to the selective RAF inhibitor through sustained inhibition of MAPK signaling. Strikingly, CRAF was a key mediator of resistance that could be overcome by the use of pan-RAF inhibitors in combination with a MEK inhibitor. Furthermore, the combination of pan-RAF and MEK inhibitors displayed strong synergy in melanoma and colorectal cancer cell lines with RAS-activating events such as RTK activation, KRAS mutation, or NF1 loss-of-function mutations. Combinations of selective RAF inhibitors, such as PLX4720 or dabrafenib, with MEK inhibitors did not incur such profound synergy, suggesting that inhibition of CRAF by pan-RAF inhibitors plays a key role in determining cellular response. Importantly, in contrast to the modest activity seen with single-agent treatment, dual pan-RAF and MEK inhibition results in the induction of apoptosis, greatly enhancing efficacy. Notably, combined pan-RAF and MEK inhibition can overcome intrinsic and acquired resistance to single-agent RAF/MEK inhibition, supporting dual pan-RAF and MEK inhibition as a novel therapeutic strategy for BRAF- and KRAS-mutant cancers.
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Affiliation(s)
- Steven R Whittaker
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts. The Broad Institute, Cambridge, Massachusetts. Division of Cancer Therapeutics, Institute of Cancer Research, London, United Kingdom
| | | | - Steve Wagner
- Division of Cancer Therapeutics, Institute of Cancer Research, London, United Kingdom
| | - Flora Luo
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts. The Broad Institute, Cambridge, Massachusetts
| | | | - Levi A Garraway
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts. The Broad Institute, Cambridge, Massachusetts. Center for Cancer Genome Discovery, Dana-Farber Cancer Institute, Boston, Massachusetts. Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
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70
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Advani SJ, Camargo MF, Seguin L, Mielgo A, Anand S, Hicks AM, Aguilera J, Franovic A, Weis SM, Cheresh DA. Kinase-independent role for CRAF-driving tumour radioresistance via CHK2. Nat Commun 2015; 6:8154. [PMID: 26333361 PMCID: PMC4559870 DOI: 10.1038/ncomms9154] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 07/24/2015] [Indexed: 12/19/2022] Open
Abstract
Although oncology therapy regimens commonly include radiation and genotoxic drugs, tumour cells typically develop resistance to these interventions. Here we report that treatment of tumours with ionizing radiation or genotoxic drugs drives p21-activated kinase 1 (PAK1)-mediated phosphorylation of CRAF on Serine 338 (pS338) triggering a kinase-independent mechanism of DNA repair and therapeutic resistance. CRAF pS338 recruits CHK2, a cell cycle checkpoint kinase involved in DNA repair, and promotes CHK2 phosphorylation/activation to enhance the tumour cell DNA damage response. Accordingly, a phospho-mimetic mutant of CRAF (S338D) is sufficient to induce the CRAF/CHK2 association enhancing tumour radioresistance, while an allosteric CRAF inhibitor sensitizes tumour cells to ionizing radiation or genotoxic drugs. Our findings establish a role for CRAF in the DNA damage response that is independent from its canonical function as a kinase. Tumors hijack cellular pathways to evade the effects of cancer therapy. Here, Advani et al. show that DNA damage-induced phosphorylation of CRAF Serine 338 triggers DNA repair by recruiting CHK2, highlighting a role for CRAF independent from its canonical function as a kinase.
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Affiliation(s)
- Sunil J Advani
- Department of Radiation Medicine and Applied Sciences at the UC San Diego Moores Cancer Center, University of California, San Diego, La Jolla, California 92093, USA
| | - Maria Fernanda Camargo
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Laetitia Seguin
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Ainhoa Mielgo
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Sudarshan Anand
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Angel M Hicks
- Department of Radiation Medicine and Applied Sciences at the UC San Diego Moores Cancer Center, University of California, San Diego, La Jolla, California 92093, USA
| | - Joseph Aguilera
- Department of Radiation Medicine and Applied Sciences at the UC San Diego Moores Cancer Center, University of California, San Diego, La Jolla, California 92093, USA
| | - Aleksandra Franovic
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Sara M Weis
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - David A Cheresh
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
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71
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Di Michele M, Stes E, Vandermarliere E, Arora R, Astorga-Wells J, Vandenbussche J, van Heerde E, Zubarev R, Bonnet P, Linders JTM, Jacoby E, Brehmer D, Martens L, Gevaert K. Limited Proteolysis Combined with Stable Isotope Labeling Reveals Conformational Changes in Protein (Pseudo)kinases upon Binding Small Molecules. J Proteome Res 2015; 14:4179-93. [PMID: 26293246 DOI: 10.1021/acs.jproteome.5b00282] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Likely due to conformational rearrangements, small molecule inhibitors may stabilize the active conformation of protein kinases and paradoxically promote tumorigenesis. We combined limited proteolysis with stable isotope labeling MS to monitor protein conformational changes upon binding of small molecules. Applying this method to the human serine/threonine kinase B-Raf, frequently mutated in cancer, we found that binding of ATP or its nonhydrolyzable analogue AMP-PNP, but not ADP, stabilized the structure of both B-Raf(WT) and B-Raf(V600E). The ATP-competitive type I B-Raf inhibitor vemurafenib and the type II inhibitor sorafenib stabilized the kinase domain (KD) but had distinct effects on the Ras-binding domain. Stabilization of the B-Raf(WT) KD was confirmed by hydrogen/deuterium exchange MS and molecular dynamics simulations. Our results are further supported by cellular assays in which we assessed cell viability and phosphorylation profiles in cells expressing B-Raf(WT) or B-Raf(V600E) in response to vemurafenib or sorafenib. Our data indicate that an overall stabilization of the B-Raf structure by specific inhibitors activates MAPK signaling and increases cell survival, helping to explain clinical treatment failure. We also applied our method to monitor conformational changes upon nucleotide binding of the pseudokinase KSR1, which holds high potential for inhibition in human diseases.
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Affiliation(s)
- Michela Di Michele
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Elisabeth Stes
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Elien Vandermarliere
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Rohit Arora
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans , Pôle de chimie, Rue de Chartres, 45100 Orléans, France
| | | | - Jonathan Vandenbussche
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Erika van Heerde
- Oncology Discovery, Janssen Research and Development, A Division of Janssen Pharmaceutica NV , Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Roman Zubarev
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet , Scheelelaberatoriet Scheeles väg 2, SE-171 77 Stockholm, Sweden
| | - Pascal Bonnet
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans , Pôle de chimie, Rue de Chartres, 45100 Orléans, France
| | - Joannes T M Linders
- Oncology Discovery, Janssen Research and Development, A Division of Janssen Pharmaceutica NV , Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Edgar Jacoby
- Oncology Discovery, Janssen Research and Development, A Division of Janssen Pharmaceutica NV , Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Dirk Brehmer
- Oncology Discovery, Janssen Research and Development, A Division of Janssen Pharmaceutica NV , Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Lennart Martens
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Kris Gevaert
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
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72
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Abstract
RAF family kinases were among the first oncoproteins to be described more than 30 years ago. They primarily act as signalling relays downstream of RAS, and their close ties to cancer have fuelled a large number of studies. However, we still lack a systems-level understanding of their regulation and mode of action. The recent discovery that the catalytic activity of RAF depends on an allosteric mechanism driven by kinase domain dimerization is providing a vital new piece of information towards a comprehensive model of RAF function. The fact that current RAF inhibitors unexpectedly induce ERK signalling by stimulating RAF dimerization also calls for a deeper structural characterization of this family of kinases.
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73
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Mendez AS, Alfaro J, Morales-Soto MA, Dar AC, McCullagh E, Gotthardt K, Li H, Acosta-Alvear D, Sidrauski C, Korennykh AV, Bernales S, Shokat KM, Walter P. Endoplasmic reticulum stress-independent activation of unfolded protein response kinases by a small molecule ATP-mimic. eLife 2015; 4. [PMID: 25986605 PMCID: PMC4436593 DOI: 10.7554/elife.05434] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 03/25/2015] [Indexed: 12/21/2022] Open
Abstract
Two ER membrane-resident transmembrane kinases, IRE1 and PERK, function as stress sensors in the unfolded protein response. IRE1 also has an endoribonuclease activity, which initiates a non-conventional mRNA splicing reaction, while PERK phosphorylates eIF2α. We engineered a potent small molecule, IPA, that binds to IRE1's ATP-binding pocket and predisposes the kinase domain to oligomerization, activating its RNase. IPA also inhibits PERK but, paradoxically, activates it at low concentrations, resulting in a bell-shaped activation profile. We reconstituted IPA-activation of PERK-mediated eIF2α phosphorylation from purified components. We estimate that under conditions of maximal activation less than 15% of PERK molecules in the reaction are occupied by IPA. We propose that IPA binding biases the PERK kinase towards its active conformation, which trans-activates apo-PERK molecules. The mechanism by which partial occupancy with an inhibitor can activate kinases may be wide-spread and carries major implications for design and therapeutic application of kinase inhibitors. DOI:http://dx.doi.org/10.7554/eLife.05434.001 Cells contain thousands of proteins that carry out the essential tasks needed for survival. Before they can work, proteins must first fold into specific three-dimensional shapes. The endoplasmic reticulum, a cellular compartment that specializes in properly folding newly made proteins into their native states, is critical for this protein maturation process. If folding-enzymes in the endoplasmic reticulum are not properly balanced with the load of proteins they must fold, the endoplasmic reticulum can be overwhelmed with unfolded proteins that accumulate, leading to ‘endoplasmic reticulum stress’. The cell copes with endoplasmic reticulum stress by triggering the ‘unfolded protein response’ (UPR). This response helps to clear the unfolded proteins by increasing the size of the endoplasmic reticulum and the concentration of folding enzymes within it, and by decreasing the influx of newly made protein into the endoplasmic reticulum. The UPR engages signaling molecules in the endoplasmic reticulum membrane, among them two signaling enzymes called IRE1 and PERK. Drugs that activate these signaling enzymes could help the cell to deal with unfolded proteins, prevent toxicity resulting from endoplasmic reticulum stress, and ward off the diseases that result from it. Mendez, Alfaro, Morales-Soto et al. developed a small molecule, called IPA (short for IRE1/PERK Activator), that was designed to bind to and activate IRE1. Serendipitously, IPA not only activated IRE1 but also activated PERK. Surprisingly, PERK activation was only observed at low IPA concentrations in which IPA occupied the active sites in only a few PERK molecules, whereas at higher concentrations and full occupancy IPA completely inhibited PERK. Mendez, Alfaro, Morales-Soto et al. proposed that, under conditions of partial IPA occupancy, a minority of IPA-bound PERK molecules assume an activated state that propagates to adjacent PERK molecules that have no IPA bound to them, and activates them. Similar dose-dependent activation was previously observed for a clinically used drug designed to inhibit a similar signaling enzyme that is important in cancer progression. Together with the observations of Mendez, Alfaro, Morales-Soto et al., these results suggest that research into similar treatments must consider that a ‘minimal dose’ can exist, below which drugs may have the opposite effect to what is desired. Further work is still needed to fully understand the mechanisms that produce such behavior. DOI:http://dx.doi.org/10.7554/eLife.05434.002
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Affiliation(s)
- Aaron S Mendez
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | | | | | - Arvin C Dar
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | | | - Katja Gotthardt
- Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Han Li
- Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Diego Acosta-Alvear
- Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Carmela Sidrauski
- Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Alexei V Korennykh
- Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | | | - Kevan M Shokat
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Peter Walter
- Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
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74
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Abstract
Protein phosphorylation is one of the most common post-translational modifications in cell regulatory mechanisms. Dimerization plays also a crucial role in the kinase activity of many kinases, including RAF, CDK2 (cyclin-dependent kinase 2) and EGFR (epidermal growth factor receptor), with heterodimers often being the most active forms. However, the structural and mechanistic details of how phosphorylation affects the activity of homo- and hetero-dimers are largely unknown. Experimentally, synthesizing protein samples with fully specified and homogeneous phosphorylation states remains a challenge for structural biology and biochemical studies. Typically, multiple changes in phosphorylation lead to activation of the same protein, which makes structural determination methods particularly difficult. It is also not well understood how the occurrence of phosphorylation and dimerization processes synergize to affect kinase activities. In the present article, we review available structural data and discuss how MD simulations can be used to model conformational transitions of RAF kinase dimers, in both their phosphorylated and unphosphorylated forms.
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75
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Nagel S, Ehrentraut S, Meyer C, Kaufmann M, Drexler HG, MacLeod RA. NFkB is activated by multiple mechanisms in hairy cell leukemia. Genes Chromosomes Cancer 2015; 54:418-32. [DOI: 10.1002/gcc.22253] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 03/04/2015] [Indexed: 12/12/2022] Open
Affiliation(s)
- Stefan Nagel
- Department of Human and Animal Cell Lines; Leibniz-Institute DSMZ - German Collection of Microorganisms and Cell Cultures; Braunschweig Germany
| | - Stefan Ehrentraut
- Department of Human and Animal Cell Lines; Leibniz-Institute DSMZ - German Collection of Microorganisms and Cell Cultures; Braunschweig Germany
| | - Corinna Meyer
- Department of Human and Animal Cell Lines; Leibniz-Institute DSMZ - German Collection of Microorganisms and Cell Cultures; Braunschweig Germany
| | - Maren Kaufmann
- Department of Human and Animal Cell Lines; Leibniz-Institute DSMZ - German Collection of Microorganisms and Cell Cultures; Braunschweig Germany
| | - Hans G. Drexler
- Department of Human and Animal Cell Lines; Leibniz-Institute DSMZ - German Collection of Microorganisms and Cell Cultures; Braunschweig Germany
| | - Roderick A.F. MacLeod
- Department of Human and Animal Cell Lines; Leibniz-Institute DSMZ - German Collection of Microorganisms and Cell Cultures; Braunschweig Germany
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76
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Margalef P, Colomer C, Villanueva A, Montagut C, Iglesias M, Bellosillo B, Salazar R, Martínez-Iniesta M, Bigas A, Espinosa L. BRAF-induced tumorigenesis is IKKα-dependent but NF-κB-independent. Sci Signal 2015; 8:ra38. [PMID: 25900832 DOI: 10.1126/scisignal.2005886] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
KRAS mutations contribute to cell proliferation and survival in numerous cancers, including colorectal cancers (CRC). One pathway through which mutant KRAS acts is an inflammatory pathway that involves the kinase IKK and activates the transcription factor NF-κB. BRAF, a kinase that is downstream of KRAS, is mutated in a subset of CRC and is predictive of poor prognosis and therapeutic resistance. We found that, in contrast to mutant KRAS, mutant BRAF (BRAF(V600E)) did not trigger NF-κB activation but instead triggered the phosphorylation of a proteolytic fragment of IKKα (p45-IKKα) in CRC cells. BRAF(V600E) CRC cells had a high abundance of phosphorylated p45-IKKα, which was decreased by a RAF inhibitor. However, the abundance and DNA binding of NF-κB in these cells were unaffected by the RAF inhibitor, and expression of BRAF(V600E) in human embryonic kidney-293T cells did not activate an NF-κB reporter. Moreover, BRAF-induced transformation of NIH-3T3 cells and BRAF-dependent transcription required phosphorylation of p45-IKKα. The kinase TAK1, which was associated with the endosomal compartment, phosphorylated p45-IKKα. Inhibition of endosomal vacuolar adenosine triphosphatase (V-ATPase) with chloroquine or bafilomycin A1 blocked p45-IKKα phosphorylation and induced apoptosis in BRAF-mutant CRC cells independent of autophagy. Treating mice with V-ATPase inhibitors reduced the growth and metastasis of BRAF(V600E) xenograft tumors in the cecum of mice.
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Affiliation(s)
- Pol Margalef
- Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Carlota Colomer
- Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Alberto Villanueva
- Laboratori de Recerca Translacional, Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Institut Català d'Oncologia, Gran Via km 2.7, Hospitalet, Barcelona 08907, Spain
| | - Clara Montagut
- Department of Oncology, IMIM, Universitat Pompeu Fabra, Barcelona 08003, Spain
| | - Mar Iglesias
- Department of Pathology, IMIM, Barcelona 08003, Spain
| | | | - Ramón Salazar
- Department of Oncology, Hospital de Bellvitge, Hospitalet, Barcelona 08907, Spain
| | - María Martínez-Iniesta
- Laboratori de Recerca Translacional, Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Institut Català d'Oncologia, Gran Via km 2.7, Hospitalet, Barcelona 08907, Spain
| | - Anna Bigas
- Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain
| | - Lluís Espinosa
- Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Parc de Recerca Biomèdica de Barcelona, Barcelona 08003, Spain.
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Fabbro D, Cowan-Jacob SW, Moebitz H. Ten things you should know about protein kinases: IUPHAR Review 14. Br J Pharmacol 2015; 172:2675-700. [PMID: 25630872 DOI: 10.1111/bph.13096] [Citation(s) in RCA: 233] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Revised: 12/31/2014] [Accepted: 01/20/2015] [Indexed: 12/12/2022] Open
Abstract
Many human malignancies are associated with aberrant regulation of protein or lipid kinases due to mutations, chromosomal rearrangements and/or gene amplification. Protein and lipid kinases represent an important target class for treating human disorders. This review focus on 'the 10 things you should know about protein kinases and their inhibitors', including a short introduction on the history of protein kinases and their inhibitors and ending with a perspective on kinase drug discovery. Although the '10 things' have been, to a certain extent, chosen arbitrarily, they cover in a comprehensive way the past and present efforts in kinase drug discovery and summarize the status quo of the current kinase inhibitors as well as knowledge about kinase structure and binding modes. Besides describing the potentials of protein kinase inhibitors as drugs, this review also focus on their limitations, particularly on how to circumvent emerging resistance against kinase inhibitors in oncological indications.
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Affiliation(s)
| | | | - Henrik Moebitz
- Novartis Institutes of Biomedical Research, Basel, Switzerland
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78
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The C2 Domain and Altered ATP-Binding Loop Phosphorylation at Ser³⁵⁹ Mediate the Redox-Dependent Increase in Protein Kinase C-δ Activity. Mol Cell Biol 2015; 35:1727-40. [PMID: 25755284 DOI: 10.1128/mcb.01436-14] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 02/24/2015] [Indexed: 11/20/2022] Open
Abstract
The diverse roles of protein kinase C-δ (PKCδ) in cellular growth, survival, and injury have been attributed to stimulus-specific differences in PKCδ signaling responses. PKCδ exerts membrane-delimited actions in cells activated by agonists that stimulate phosphoinositide hydrolysis. PKCδ is released from membranes as a Tyr(313)-phosphorylated enzyme that displays a high level of lipid-independent activity and altered substrate specificity during oxidative stress. This study identifies an interaction between PKCδ's Tyr(313)-phosphorylated hinge region and its phosphotyrosine-binding C2 domain that controls PKCδ's enzymology indirectly by decreasing phosphorylation in the kinase domain ATP-positioning loop at Ser(359). We show that wild-type (WT) PKCδ displays a strong preference for substrates with serine as the phosphoacceptor residue at the active site when it harbors phosphomimetic or bulky substitutions at Ser(359.) In contrast, PKCδ-S359A displays lipid-independent activity toward substrates with either a serine or threonine as the phosphoacceptor residue. Additional studies in cardiomyocytes show that oxidative stress decreases Ser(359) phosphorylation on native PKCδ and that PKCδ-S359A overexpression increases basal levels of phosphorylation on substrates with both phosphoacceptor site serine and threonine residues. Collectively, these studies identify a C2 domain-pTyr(313) docking interaction that controls ATP-positioning loop phosphorylation as a novel, dynamically regulated, and physiologically relevant structural determinant of PKCδ catalytic activity.
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79
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Samatar AA, Poulikakos PI. Targeting RAS-ERK signalling in cancer: promises and challenges. Nat Rev Drug Discov 2015; 13:928-42. [PMID: 25435214 DOI: 10.1038/nrd4281] [Citation(s) in RCA: 798] [Impact Index Per Article: 88.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The RAS-RAF-MEK-ERK signalling pathway is hyperactivated in a high percentage of tumours, most frequently owing to activating mutations of the KRAS, NRAS and BRAF genes. Recently, the use of compounds targeting components of ERK signalling, such as RAF or MEK inhibitors, has led to substantial improvement in clinical outcome in metastatic melanoma and has shown promising clinical activity in additional tumour types. However, response rates are highly variable and the efficacy of these drugs is primarily limited by the development of resistance. Both intrinsic and acquired resistance to RAF and MEK inhibitors are frequently associated with the persistence of ERK signalling in the presence of the drug, implying the need for more innovative approaches to target the pathway.
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Affiliation(s)
- Ahmed A Samatar
- TheraMet Biosciences, 6 Jacob Drive, Princeton Junction, New Jersey 08550, USA
| | - Poulikos I Poulikakos
- Department of Oncological Sciences and Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, New York 10029, USA
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80
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Tumor flare after start of RAF inhibition in KRAS mutated NSCLC: A case report. Lung Cancer 2015; 87:201-3. [DOI: 10.1016/j.lungcan.2014.11.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 11/08/2014] [Accepted: 11/23/2014] [Indexed: 12/25/2022]
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81
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Fabbro D. 25 Years of Small Molecular Weight Kinase Inhibitors: Potentials and Limitations. Mol Pharmacol 2014; 87:766-75. [DOI: 10.1124/mol.114.095489] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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82
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Co-targeting BRAF and cyclin dependent kinases 4/6 for BRAF mutant cancers. Pharmacol Ther 2014; 149:139-49. [PMID: 25550229 DOI: 10.1016/j.pharmthera.2014.12.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 12/17/2014] [Indexed: 12/19/2022]
Abstract
Selective BRAF inhibitors have demonstrated significant clinical benefit in melanoma patients harboring oncogenic BRAF mutations. However, the majority of such patients either exhibit de novo resistance from the beginning of the treatment or acquire resistance and eventually relapse. Despite tremendous progress in understanding the underlying mechanisms of resistance, overcoming resistance to BRAF inhibitors remains an unmet medical need. Constitutive activation of cyclin-dependent kinases (CDK) 4/6 as a result of genetic aberrations including CDKN2A inactivation and CCND1 amplification is common across many cancer types and frequently co-occurs with oncogenic BRAF mutations. Also, cyclin D1 overexpression is a common feature of resistance to BRAF inhibitors. Here we review CDK4/6 as a therapeutic target in BRAF mutant cancers and discuss emerging evidence supporting a critical role of cyclin D1/CDK4/6 axis in de novo and acquired resistance to BRAF inhibitors. Co-targeting CDK4/6 and BRAF could be a more effective therapy to augment clinical response of BRAF inhibitors and overcome resistance in BRAF mutant cancers.
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83
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Mandal P, Berger SB, Pillay S, Moriwaki K, Huang C, Guo H, Lich JD, Finger J, Kasparcova V, Votta B, Ouellette M, King BW, Wisnoski D, Lakdawala AS, DeMartino MP, Casillas LN, Haile PA, Sehon CA, Marquis RW, Upton J, Daley-Bauer LP, Roback L, Ramia N, Dovey CM, Carette JE, Chan FKM, Bertin J, Gough PJ, Mocarski ES, Kaiser WJ. RIP3 induces apoptosis independent of pronecrotic kinase activity. Mol Cell 2014; 56:481-95. [PMID: 25459880 DOI: 10.1016/j.molcel.2014.10.021] [Citation(s) in RCA: 545] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 09/11/2014] [Accepted: 10/17/2014] [Indexed: 11/17/2022]
Abstract
Receptor-interacting protein kinase 3 (RIP3 or RIPK3) has emerged as a central player in necroptosis and a potential target to control inflammatory disease. Here, three selective small-molecule compounds are shown to inhibit RIP3 kinase-dependent necroptosis, although their therapeutic value is undermined by a surprising, concentration-dependent induction of apoptosis. These compounds interact with RIP3 to activate caspase 8 (Casp8) via RHIM-driven recruitment of RIP1 (RIPK1) to assemble a Casp8-FADD-cFLIP complex completely independent of pronecrotic kinase activities and MLKL. RIP3 kinase-dead D161N mutant induces spontaneous apoptosis independent of compound, whereas D161G, D143N, and K51A mutants, like wild-type, only trigger apoptosis when compound is present. Accordingly, RIP3-K51A mutant mice (Rip3(K51A/K51A)) are viable and fertile, in stark contrast to the perinatal lethality of Rip3(D161N/D161N) mice. RIP3 therefore holds both necroptosis and apoptosis in balance through a Ripoptosome-like platform. This work highlights a common mechanism unveiling RHIM-driven apoptosis by therapeutic or genetic perturbation of RIP3.
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Affiliation(s)
- Pratyusha Mandal
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Scott B Berger
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Sirika Pillay
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kenta Moriwaki
- Department of Pathology, Immunology and Microbiology Program, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Chunzi Huang
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Hongyan Guo
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - John D Lich
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Joshua Finger
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Viera Kasparcova
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Bart Votta
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Michael Ouellette
- Molecular Discovery Research, Platform Technologies and Science, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Bryan W King
- Molecular Discovery Research, Platform Technologies and Science, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - David Wisnoski
- Molecular Discovery Research, Platform Technologies and Science, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Ami S Lakdawala
- Molecular Discovery Research, Platform Technologies and Science, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Michael P DeMartino
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Linda N Casillas
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Pamela A Haile
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Clark A Sehon
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Robert W Marquis
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Jason Upton
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Lisa P Daley-Bauer
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Linda Roback
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Nancy Ramia
- Department of Pathology, Immunology and Microbiology Program, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Cole M Dovey
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jan E Carette
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Francis Ka-Ming Chan
- Department of Pathology, Immunology and Microbiology Program, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - John Bertin
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Peter J Gough
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Edward S Mocarski
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - William J Kaiser
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA.
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84
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Ferrari de Andrade L, Ngiow SF, Stannard K, Rusakiewicz S, Kalimutho M, Khanna KK, Tey SK, Takeda K, Zitvogel L, Martinet L, Smyth MJ. Natural killer cells are essential for the ability of BRAF inhibitors to control BRAFV600E-mutant metastatic melanoma. Cancer Res 2014; 74:7298-308. [PMID: 25351955 DOI: 10.1158/0008-5472.can-14-1339] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BRAF(V600E) is a major oncogenic mutation found in approximately 50% of human melanoma that confers constitutive activation of the MAPK pathway and increased melanoma growth. Inhibition of BRAF(V600E) by oncogene targeting therapy increases overall survival of patients with melanoma, but is unable to produce many durable responses. Adaptive drug resistance remains the main limitation to BRAF(V600E) inhibitor clinical efficacy and immune-based strategies could be useful to overcome disease relapse. Tumor microenvironment greatly differs between visceral metastasis and primary cutaneous melanoma, and the mechanisms involved in the antimetastatic efficacy of BRAF(V600E) inhibitors remain to be determined. To address this question, we developed a metastatic BRAF(V600E)-mutant melanoma cell line and demonstrated that the antimetastatic properties of BRAF inhibitor PLX4720 (a research analogue of vemurafenib) require host natural killer (NK) cells and perforin. Indeed, PLX4720 not only directly limited BRAF(V600E)-induced tumor cell proliferation, but also affected NK cell functions. We showed that PLX4720 increases the phosphorylation of ERK1/2, CD69 expression, and proliferation of mouse NK cells in vitro. NK cell frequencies were significantly enhanced by PLX4720 specifically in the lungs of mice with BRAF(V600E) lung metastases. Furthermore, PLX4720 also increased human NK cell pERK1/2, CD69 expression, and IFNγ release in the context of anti-NKp30 and IL2 stimulation. Overall, this study supports the idea that additional NK cell-based immunotherapy (by checkpoint blockade or agonists or cytokines) may combine well with BRAF(V600E) inhibitor therapy to promote more durable responses in melanoma.
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Affiliation(s)
- Lucas Ferrari de Andrade
- Laboratorio de Pesquisa em Células Inflamatórias e Neoplásicas Group, Universidade Federal do Paraná, Curitiba, Paraná, Brazil. Immunology in Cancer and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Shin F Ngiow
- Immunology in Cancer and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Kimberley Stannard
- Immunology in Cancer and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Sylvie Rusakiewicz
- Gustave Roussy Cancer Campus, Villejuif, France. INSERM U1015, Villejuif, France. Center of Clinical Investigations in Biotherapies of Cancer (CICBT) 1428, Villejuif, France
| | - Murugan Kalimutho
- Signal Transduction Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Kum Kum Khanna
- Signal Transduction Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Siok-Keen Tey
- Bone Marrow Transplant Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Kazuyoshi Takeda
- Department of Immunology, Juntendo University School of Medicine, Hongo, Bunkyo-ku, Tokyo, Japan
| | - Laurence Zitvogel
- Gustave Roussy Cancer Campus, Villejuif, France. INSERM U1015, Villejuif, France. Université Paris Sud-XI, Faculté de Médecine, Le Kremlin Bicêtre, France. Department of Medical Oncology, IGR, Villejuif, France
| | - Ludovic Martinet
- Immunology in Cancer and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Mark J Smyth
- Immunology in Cancer and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia. School of Medicine, University of Queensland, Herston, Queensland, Australia.
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85
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Liu SM, Lu J, Lee HC, Chung FH, Ma N. miR-524-5p suppresses the growth of oncogenic BRAF melanoma by targeting BRAF and ERK2. Oncotarget 2014; 5:9444-59. [PMID: 25275294 PMCID: PMC4253445 DOI: 10.18632/oncotarget.2452] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 06/20/2014] [Indexed: 01/07/2023] Open
Abstract
It has been well documented that miRNAs can modulate the effectiveness of cancer-associated signaling pathways. Mitogen-activated protein kinase (MAPK/ERK) signaling plays an essential role in the progression of many cancers, including melanoma and colon cancers. However, no single miRNA is reported to directly target multiple components of the MAPK/ERK pathway. We performed a miRNA PCR array screening with various MAPK/ERK signaling activities. The miRNA array data revealed that the expression of miR-524-5p was decreased in cells with an active MAPK/ERK pathway and confirmed that the expression of miR-524-5p is inversely associated with the activity of the MAPK/ERK pathway. We demonstrated that miR-524-5p directly binds to the 3'-untranslated regions of both BRAFandERK2 and suppresses the expression of these proteins. Because BRAF and ERK2 are the main components of MAPK signaling, the overexpression of miR-524-5p effectively inhibits MAPK/ERK signaling, tumor proliferation, and melanoma cell migration. Moreover, tumors overexpressing miR-524-5p were significantly smaller than those of the negative control mice. Our findings provide new insight into the role of miR-524-5p as an important miRNA that negatively regulates the MAPK/ERK signaling pathway, suggesting that miR-524-5p could be a potent therapeutic candidate for melanoma treatment.
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Affiliation(s)
- Szu-Mam Liu
- Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
| | - Jean Lu
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Hoong-Chien Lee
- Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
- Center for Dynamical Biomarkers and Translational Medicine, National Central University, Jhongli, Taiwan
- Department of Physics, Chung Yuan Christian University, Jhongli, Taiwan
| | - Feng-Hsiang Chung
- Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
- Center for Dynamical Biomarkers and Translational Medicine, National Central University, Jhongli, Taiwan
| | - Nianhan Ma
- Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
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86
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Sun C, Bernards R. Feedback and redundancy in receptor tyrosine kinase signaling: relevance to cancer therapies. Trends Biochem Sci 2014; 39:465-74. [PMID: 25239057 DOI: 10.1016/j.tibs.2014.08.010] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 08/26/2014] [Accepted: 08/26/2014] [Indexed: 12/19/2022]
Abstract
Mammalian cells have multiple regulatory mechanisms to deal with perturbations in cellular homeostasis, including feedback loops and crosstalk between the major signaling pathways. While these mechanisms are critically required to help cells survive under dynamic physiological circumstances, they also pose an impediment to the effective treatment of cancer. In this review, we describe what has been learned about interactions between receptor tyrosine kinase-dependent signaling pathways, and how this knowledge can be used to design rational and more effective combination therapies for cancer.
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Affiliation(s)
- Chong Sun
- Division of Molecular Carcinogenesis and Cancer Genomics Netherlands, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - René Bernards
- Division of Molecular Carcinogenesis and Cancer Genomics Netherlands, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
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87
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Haling JR, Sudhamsu J, Yen I, Sideris S, Sandoval W, Phung W, Bravo BJ, Giannetti AM, Peck A, Masselot A, Morales T, Smith D, Brandhuber BJ, Hymowitz SG, Malek S. Structure of the BRAF-MEK complex reveals a kinase activity independent role for BRAF in MAPK signaling. Cancer Cell 2014; 26:402-413. [PMID: 25155755 DOI: 10.1016/j.ccr.2014.07.007] [Citation(s) in RCA: 147] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 04/15/2014] [Accepted: 07/11/2014] [Indexed: 01/07/2023]
Abstract
Numerous oncogenic mutations occur within the BRAF kinase domain (BRAF(KD)). Here we show that stable BRAF-MEK1 complexes are enriched in BRAF(WT) and KRAS mutant (MT) cells but not in BRAF(MT) cells. The crystal structure of the BRAF(KD) in a complex with MEK1 reveals a face-to-face dimer sensitive to MEK1 phosphorylation but insensitive to BRAF dimerization. Structure-guided studies reveal that oncogenic BRAF mutations function by bypassing the requirement for BRAF dimerization for activity or weakening the interaction with MEK1. Finally, we show that conformation-specific BRAF inhibitors can sequester a dormant BRAF-MEK1 complex resulting in pathway inhibition. Taken together, these findings reveal a regulatory role for BRAF in the MAPK pathway independent of its kinase activity but dependent on interaction with MEK.
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Affiliation(s)
- Jacob R Haling
- Department of Biochemical and Cellular Pharmacology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Jawahar Sudhamsu
- Department of Structural Biology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Ivana Yen
- Department of Biochemical and Cellular Pharmacology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Steve Sideris
- Department of Biochemical and Cellular Pharmacology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Wendy Sandoval
- Department of Protein Chemistry, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Wilson Phung
- Department of Protein Chemistry, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Brandon J Bravo
- Department of Biochemical and Cellular Pharmacology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Anthony M Giannetti
- Department of Biochemical and Cellular Pharmacology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Ariana Peck
- Department of Biochemical and Cellular Pharmacology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Alexandre Masselot
- Department of Bioinformatics, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Tony Morales
- Department of Structural Biology, Array BioPharma, Inc., 3200 Walnut Street, Boulder, CO 80301, USA
| | - Darin Smith
- Department of Structural Biology, Array BioPharma, Inc., 3200 Walnut Street, Boulder, CO 80301, USA
| | - Barbara J Brandhuber
- Department of Structural Biology, Array BioPharma, Inc., 3200 Walnut Street, Boulder, CO 80301, USA
| | - Sarah G Hymowitz
- Department of Structural Biology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
| | - Shiva Malek
- Department of Biochemical and Cellular Pharmacology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
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88
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Allosteric MEK1/2 inhibitor refametinib (BAY 86-9766) in combination with sorafenib exhibits antitumor activity in preclinical murine and rat models of hepatocellular carcinoma. Neoplasia 2014; 15:1161-71. [PMID: 24204195 DOI: 10.1593/neo.13812] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 09/09/2013] [Accepted: 09/09/2013] [Indexed: 01/09/2023] Open
Abstract
OBJECTIVE The objectives of the study were to evaluate the allosteric mitogen-activated protein kinase kinase (MEK) inhibitor BAY 86-9766 in monotherapy and in combination with sorafenib in orthotopic and subcutaneous hepatocellular carcinoma (HCC) models with different underlying etiologies in two species. DESIGN Antiproliferative potential of BAY 86-9766 and synergistic effects with sorafenib were studied in several HCC cell lines. Relevant pathway signaling was studied in MH3924a cells. For in vivo testing, the HCC cells were implanted subcutaneously or orthotopically. Survival and mode of action (MoA) were analyzed. RESULTS BAY 86-9766 exhibited potent antiproliferative activity in HCC cell lines with half-maximal inhibitory concentration values ranging from 33 to 762 nM. BAY 86-9766 was strongly synergistic with sorafenib in suppressing tumor cell proliferation and inhibiting phosphorylation of the extracellular signal-regulated kinase (ERK). BAY 86-9766 prolonged survival in Hep3B xenografts, murine Hepa129 allografts, and MH3924A rat allografts. Additionally, tumor growth, ascites formation, and serum alpha-fetoprotein levels were reduced. Synergistic effects in combination with sorafenib were shown in Huh-7, Hep3B xenografts, and MH3924A allografts. On the signaling pathway level, the combination of BAY 86-9766 and sorafenib led to inhibition of the upregulatory feedback loop toward MEK phosphorylation observed after BAY 86-9766 monotreatment. With regard to the underlying MoA, inhibition of ERK phosphorylation, tumor cell proliferation, and microvessel density was observed in vivo. CONCLUSION BAY 86-9766 shows potent single-agent antitumor activity and acts synergistically in combination with sorafenib in preclinical HCC models. These results support the ongoing clinical development of BAY 86-9766 and sorafenib in advanced HCC.
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89
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Yuan TL, Fellmann C, Lee CS, Ritchie CD, Thapar V, Lee LC, Hsu DJ, Grace D, Carver JO, Zuber J, Luo J, McCormick F, Lowe SW. Development of siRNA payloads to target KRAS-mutant cancer. Cancer Discov 2014; 4:1182-1197. [PMID: 25100204 PMCID: PMC4184972 DOI: 10.1158/2159-8290.cd-13-0900] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
UNLABELLED RNAi is a powerful tool for target identification and can lead to novel therapies for pharmacologically intractable targets such as KRAS. RNAi therapy must combine potent siRNA payloads with reliable in vivo delivery for efficient target inhibition. We used a functional "Sensor" assay to establish a library of potent siRNAs against RAS pathway genes and to show that they efficiently suppress their targets at low dose. This reduces off-target effects and enables combination gene knockdown. We administered Sensor siRNAs in vitro and in vivo and validated the delivery of KRAS siRNA alone and siRNA targeting the complete RAF effector node (A/B/CRAF) as promising strategies to treat KRAS-mutant colorectal cancer. We further demonstrate that improved therapeutic efficacy is achieved by formulating siRNA payloads that combine both single-gene siRNA and node-targeted siRNAs (KRAS + PIK3CA/B). The customizable nature of Sensor siRNA payloads offers a universal platform for the combination target identification and development of RNAi therapeutics. SIGNIFICANCE To advance RNAi therapy for KRAS-mutant cancer, we developed a validated siRNA library against RAS pathway genes that enables combination gene silencing. Using an in vivo model for real-time siRNA delivery tracking, we show that siRNA-mediated inhibition of KRAS as well as RAF or PI3K combinations can impair KRAS-mutant colorectal cancer in xenograft models.
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Affiliation(s)
- Tina L Yuan
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA 94158, USA
| | - Christof Fellmann
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Chih-Shia Lee
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Cayde D Ritchie
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA 94158, USA
| | - Vishal Thapar
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.,Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Liam C Lee
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Dennis J Hsu
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Danielle Grace
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.,Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Joseph O Carver
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Johannes Zuber
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.,Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, 1030 Vienna, Austria
| | - Ji Luo
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Frank McCormick
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA 94158, USA
| | - Scott W Lowe
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.,Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.,Howard Hughes Medical Institute, New York, NY 10065, USA
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90
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Holderfield M, Deuker MM, McCormick F, McMahon M. Targeting RAF kinases for cancer therapy: BRAF-mutated melanoma and beyond. Nat Rev Cancer 2014; 14:455-67. [PMID: 24957944 PMCID: PMC4250230 DOI: 10.1038/nrc3760] [Citation(s) in RCA: 588] [Impact Index Per Article: 58.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The identification of mutationally activated BRAF in many cancers altered our conception of the part played by the RAF family of protein kinases in oncogenesis. In this Review, we describe the development of BRAF inhibitors and the results that have emerged from their analysis in both the laboratory and the clinic. We discuss the spectrum of RAF mutations in human cancer and the complex interplay between the tissue of origin and the response to RAF inhibition. Finally, we enumerate mechanisms of resistance to BRAF inhibition that have been characterized and postulate how strategies of RAF pathway inhibition may be extended in scope to benefit not only the thousands of patients who are diagnosed annually with BRAF-mutated metastatic melanoma but also the larger patient population with malignancies harbouring mutationally activated RAF genes that are ineffectively treated with the current generation of BRAF kinase inhibitors.
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Affiliation(s)
| | | | - Frank McCormick
- Corresponding Authors: Frank McCormick & Martin McMahon, Diller Family Cancer Research Bldg., 1450 Third Street, University of California, San Francisco, CA 94158, USA, &
| | - Martin McMahon
- Corresponding Authors: Frank McCormick & Martin McMahon, Diller Family Cancer Research Bldg., 1450 Third Street, University of California, San Francisco, CA 94158, USA, &
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91
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"RAF" neighborhood: protein-protein interaction in the Raf/Mek/Erk pathway. FEBS Lett 2014; 588:2398-406. [PMID: 24937142 PMCID: PMC4099524 DOI: 10.1016/j.febslet.2014.06.025] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 06/05/2014] [Accepted: 06/06/2014] [Indexed: 12/19/2022]
Abstract
The Raf/Mek/Erk signaling pathway, activated downstream of Ras primarily to promote proliferation, represents the best studied of the evolutionary conserved MAPK cascades. The investigation of the pathway has continued unabated since its discovery roughly 30 years ago. In the last decade, however, the identification of unexpected in vivo functions of pathway components, as well as the discovery of Raf mutations in human cancer, the ensuing quest for inhibitors, and the efforts to understand their mechanism of action, have boosted interest tremendously. From this large body of work, protein-protein interaction has emerged as a recurrent, crucial theme. This review focuses on the role of protein complexes in the regulation of the Raf/Mek/Erk pathway and in its cross-talk with other signaling cascades. Mapping these interactions and finding a way of exploiting them for therapeutic purposes is one of the challenges of future molecule-targeted therapy.
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92
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Shtivelman E, Davies MA, Hwu P, Yang J, Lotem M, Oren M, Flaherty KT, Fisher DE. Pathways and therapeutic targets in melanoma. Oncotarget 2014; 5:1701-52. [PMID: 24743024 PMCID: PMC4039128 DOI: 10.18632/oncotarget.1892] [Citation(s) in RCA: 164] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 04/07/2014] [Indexed: 02/07/2023] Open
Abstract
This review aims to summarize the current knowledge of molecular pathways and their clinical relevance in melanoma. Metastatic melanoma was a grim diagnosis, but in recent years tremendous advances have been made in treatments. Chemotherapy provided little benefit in these patients, but development of targeted and new immune approaches made radical changes in prognosis. This would not have happened without remarkable advances in understanding the biology of disease and tremendous progress in the genomic (and other "omics") scale analyses of tumors. The big problems facing the field are no longer focused exclusively on the development of new treatment modalities, though this is a very busy area of clinical research. The focus shifted now to understanding and overcoming resistance to targeted therapies, and understanding the underlying causes of the heterogeneous responses to immune therapy.
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Affiliation(s)
| | | | - Patrick Hwu
- University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - James Yang
- National Cancer Institute, NIH, Washington DC, USA
| | - Michal Lotem
- Hadassah Hebrew University Hospital, Jerusalem, Israel
| | - Moshe Oren
- The Weizmann Institute of Science, Rehovot, Israel
| | | | - David E. Fisher
- Massachusetts General Hospital Cancer Center, Boston, MA, USA
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93
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Holderfield M, Nagel TE, Stuart DD. Mechanism and consequences of RAF kinase activation by small-molecule inhibitors. Br J Cancer 2014; 111:640-5. [PMID: 24642617 PMCID: PMC4134487 DOI: 10.1038/bjc.2014.139] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 02/18/2014] [Accepted: 02/24/2014] [Indexed: 02/06/2023] Open
Abstract
Despite the clinical success of RAF inhibitors in BRAF-mutated melanomas, attempts to target RAF kinases in the context of RAS-driven or otherwise RAF wild-type tumours have not only been ineffective, but RAF inhibitors appear to aggravate tumorigenesis in these settings. Subsequent preclinical investigation has revealed several regulatory mechanisms, feedback pathways and unexpected enzymatic quirks in the MAPK pathway, which may explain this paradox. In this review, we cover the various proposed molecular mechanisms for the RAF paradox, the clinical consequences and strategies to overcome it.
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Affiliation(s)
- M Holderfield
- UCSF Helen Diller Family Comprehensive Cancer Research, University of California San Francisco, San Francisco, CA 94143-0128, USA
| | - T E Nagel
- Novartis Institutes for Biomedical Research, Emeryville, CA 94523, USA
| | - D D Stuart
- Novartis Institutes for Biomedical Research, Emeryville, CA 94523, USA
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94
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Stephen AG, Esposito D, Bagni RK, McCormick F. Dragging ras back in the ring. Cancer Cell 2014; 25:272-81. [PMID: 24651010 DOI: 10.1016/j.ccr.2014.02.017] [Citation(s) in RCA: 610] [Impact Index Per Article: 61.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Revised: 02/10/2014] [Accepted: 02/21/2014] [Indexed: 12/13/2022]
Abstract
Ras proteins play a major role in human cancers but have not yielded to therapeutic attack. Ras-driven cancers are among the most difficult to treat and often excluded from therapies. The Ras proteins have been termed "undruggable," based on failures from an era in which understanding of signaling transduction, feedback loops, redundancy, tumor heterogeneity, and Ras' oncogenic role was poor. Structures of Ras oncoproteins bound to their effectors or regulators are unsolved, and it is unknown precisely how Ras proteins activate their downstream targets. These knowledge gaps have impaired development of therapeutic strategies. A better understanding of Ras biology and biochemistry, coupled with new ways of targeting undruggable proteins, is likely to lead to new ways of defeating Ras-driven cancers.
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Affiliation(s)
- Andrew G Stephen
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, P.O. Box B, Frederick, MD 21702, USA
| | - Dominic Esposito
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, P.O. Box B, Frederick, MD 21702, USA
| | - Rachel K Bagni
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, P.O. Box B, Frederick, MD 21702, USA
| | - Frank McCormick
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, P.O. Box B, Frederick, MD 21702, USA; UCSF Helen Diller Family Comprehensive Cancer Center, Room 371, 1450 3(rd) Street, P.O. Box 589001, San Francisco, CA 94158-9001, USA.
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95
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Holderfield M, Lorenzana E, Weisburd B, Lomovasky L, Boussemart L, Lacroix L, Tomasic G, Favre M, Vagner S, Robert C, Ghoddusi M, Daniel D, Pryer N, McCormick F, Stuart D. Vemurafenib cooperates with HPV to promote initiation of cutaneous tumors. Cancer Res 2014; 74:2238-45. [PMID: 24523442 DOI: 10.1158/0008-5472.can-13-1065-t] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Treatment with RAF inhibitors such as vemurafenib causes the development of cutaneous squamous cell carcinomas (cSCC) or keratoacanthomas as a side effect in 18% to 30% of patients. It is known that RAF inhibitors activate the mitogen-activated protein kinase (MAPK) pathway and stimulate growth of RAS-mutated cells, possibly accounting for up to 60% of cSCC or keratoacanthoma lesions with RAS mutations, but other contributing events are obscure. To identify such events, we evaluated tumors from patients treated with vemurafenib for the presence of human papilloma virus (HPV) DNA and identified 13% to be positive. Using a transgenic murine model of HPV-driven cSCC (K14-HPV16 mice), we conducted a functional test to determine whether administration of RAF inhibitors could promote cSCC in HPV-infected tissues. Vemurafenib treatment elevated MAPK markers and increased cSCC incidence from 22% to 70% in this model. Furthermore, 55% of the cSCCs arising in vemurafenib-treated mice exhibited a wild-type Ras genotype, consistent with the frequency observed in human patients. Our results argue that HPV cooperates with vemurafenib to promote tumorigenesis, in either the presence or absence of RAS mutations.
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Affiliation(s)
- Matthew Holderfield
- Authors' Affiliations: Novartis Institutes for Biomedical Research, Emeryville; UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California; Dermatology Unit and INSERM U 981; Department of Medical Biology and Pathology; Laboratory and Biobank; INSERM U 981, Institut Gustave Roussy, Villejuif Paris-Sud; and Unité de Génétique, Papillomavirus et Cancer Humain, Institut Pasteur, Paris, France
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96
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Rizos H, Menzies AM, Pupo GM, Carlino MS, Fung C, Hyman J, Haydu LE, Mijatov B, Becker TM, Boyd SC, Howle J, Saw R, Thompson JF, Kefford RF, Scolyer RA, Long GV. BRAF inhibitor resistance mechanisms in metastatic melanoma: spectrum and clinical impact. Clin Cancer Res 2014; 20:1965-77. [PMID: 24463458 DOI: 10.1158/1078-0432.ccr-13-3122] [Citation(s) in RCA: 388] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Multiple BRAF inhibitor resistance mechanisms have been described, however, their relative frequency, clinical correlates, and effect on subsequent therapy have not been assessed in patients with metastatic melanoma. EXPERIMENTAL DESIGN Fifty-nine BRAF(V600)-mutant melanoma metastases from patients treated with dabrafenib or vemurafenib were analyzed. The genetic profile of resistance mechanisms and tumor signaling pathway activity was correlated with clinicopathologic features and therapeutic outcomes. RESULTS Resistance mechanisms were identified in 58% progressing tumors and BRAF alterations were common. Gene expression analysis revealed that mitogen-activated protein kinase (MAPK) activity remained inhibited in 21% of resistant tumors, and the outcomes of patients with these tumors were poor. Resistance mechanisms also occurred in pretreatment biopsies and heterogeneity of resistance mechanisms occurred within patients and within tumors. There were no responses to subsequent targeted therapy, even when a progressing tumor had a resistance mechanism predicted to be responsive. CONCLUSIONS Selecting sequential drugs based on the molecular characteristics of a single progressing biopsy is unlikely to provide improved responses, and first-line therapies targeting multiple pathways will be required.
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Affiliation(s)
- Helen Rizos
- Authors' Affiliations: Westmead Institute for Cancer Research, The University of Sydney at Westmead Millennium Institute; Departments of Medical Oncology and Surgical Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Westmead; Melanoma Institute Australia; Disciplines of Pathology, Medicine, and Surgery, Sydney Medical School, The University of Sydney, Sydney; Departments of Melanoma and Surgical Oncology and Tissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia
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97
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Doma E, Rupp C, Varga A, Kern F, Riegler B, Baccarini M. Skin tumorigenesis stimulated by Raf inhibitors relies upon Raf functions that are dependent and independent of ERK. Cancer Res 2013; 73:6926-37. [PMID: 24129679 DOI: 10.1158/0008-5472.can-13-0748] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RAF inhibitors achieve unprecedented but mainly transient clinical responses in patients with melanoma whose tumors harbor an activating BRAF mutation. One notable side-effect of RAF inhibitors is the stimulation of cutaneous skin tumors, arising in about 30% of patients receiving these drugs, which are thought to develop as a result of inhibitor-induced activation of wild-type Raf in occult precursor skin lesions. This effect raises the possibility that less manageable tumors might also arise in other epithelial tissues. Here we provide preclinical evidence supporting this disquieting hypothesis by showing that the RAF inhibitors PLX-4032 (vemurafenib) and GDC-0879 precipitate the development of cell-autonomous, Ras-driven tumors in skin and gastric epithelia. The magnitude of the effects correlated with the inhibitors' relative abilities to induce ERK activation. Epidermis-restricted ablation of either B-Raf or C-Raf prevented PLX-4032-induced ERK activation and tumorigenesis. In contrast, GDC-0879 induced ERK activation and tumorigenesis in B-Raf-deficient epidermis, whereas C-Raf ablation blocked GDC-0879-induced tumorigenesis (despite strong ERK activation) by preventing Rokα-mediated keratinocyte dedifferentiation. Thus, inhibitor-induced ERK activation did not require a specific Raf kinase. ERK activation was necessary, but not sufficient for Ras + Raf inhibitor-induced tumorigenesis, whereas C-Raf downregulation of Rokα was essential even in the face of sustained ERK signaling to prevent differentiation and promote tumorigenesis. Taken together, our findings suggest that combination therapies targeting ERK-dependent and -independent functions of Raf may be more efficient but also safer for cancer treatment.
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Affiliation(s)
- Eszter Doma
- Authors' Affiliation: Department of Microbiology, Immunobiology and Genetics, University of Vienna, Max F. Perutz Laboratories, Vienna, Austria
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98
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Nakamura A, Arita T, Tsuchiya S, Donelan J, Chouitar J, Carideo E, Galvin K, Okaniwa M, Ishikawa T, Yoshida S. Antitumor activity of the selective pan-RAF inhibitor TAK-632 in BRAF inhibitor-resistant melanoma. Cancer Res 2013; 73:7043-55. [PMID: 24121489 DOI: 10.1158/0008-5472.can-13-1825] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The mitogen-activated protein kinase (MAPK) pathway is particularly important for the survival and proliferation of melanoma cells. Somatic mutations in BRAF and NRAS are frequently observed in melanoma. Recently, the BRAF inhibitors vemurafenib and dabrafenib have emerged as promising agents for the treatment of melanoma patients with BRAF-activating mutations. However, as BRAF inhibitors induce RAF paradoxical activation via RAF dimerization in BRAF wild-type cells, rapid emergence of acquired resistance and secondary skin tumors as well as presence of few effective treatment options for melanoma bearing wild-type BRAF (including NRAS-mutant melanoma) are clinical concerns. Here, we demonstrate that the selective pan-RAF inhibitor TAK-632 suppresses RAF activity in BRAF wild-type cells with minimal RAF paradoxical activation. Our analysis using RNAi and TAK-632 in preclinical models reveals that the MAPK pathway of NRAS-mutated melanoma cells is highly dependent on RAF. We also show that TAK-632 induces RAF dimerization but inhibits the kinase activity of the RAF dimer, probably because of its slow dissociation from RAF. As a result, TAK-632 demonstrates potent antiproliferative effects both on NRAS-mutated melanoma cells and BRAF-mutated melanoma cells with acquired resistance to BRAF inhibitors through NRAS mutation or BRAF truncation. Furthermore, we demonstrate that the combination of TAK-632 and the MAPK kinase (MEK) inhibitor TAK-733 exhibits synergistic antiproliferative effects on these cells. Our findings characterize the unique features of TAK-632 as a pan-RAF inhibitor and provide rationale for its further investigation in NRAS-mutated melanoma and a subset of BRAF-mutated melanomas refractory to BRAF inhibitors.
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Affiliation(s)
- Akito Nakamura
- Authors' Affiliation: Oncology Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
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99
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Menzies AM, Kefford RF, Long GV. Paradoxical oncogenesis: are all BRAF inhibitors equal? Pigment Cell Melanoma Res 2013; 26:611-5. [PMID: 23795808 DOI: 10.1111/pcmr.12132] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 06/19/2013] [Indexed: 12/20/2022]
Abstract
Cutaneous squamous cell carcinoma (cSCC) is a concerning toxicity with BRAF inhibitors in the treatment for melanoma. While the two drugs shown to improve survival, vemurafenib, and dabrafenib, have similar efficacy, the reported rates of cSCC are quite different. Drawing upon preclinical and clinical trial data, this article discusses the potential factors behind the different cSCC incidences reported with the two BRAF inhibitors and provides a strategic approach to understand this issue further.
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100
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Abstract
ERK pathway activation in cells expressing wild-type BRAF is a well-reported, clinically-relevant adverse effect of the otherwise impressive response of BRAF(V600E)-mutated melanomas to RAF inhibitors. In this issue of Cancer Cell, Holderfield and colleagues show that RAF autoinhibition underpins this paradox, further complicating therapeutic strategies centered around RAF.
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Affiliation(s)
- Fiona Hey
- Department of Biochemistry, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
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