title: Vemurafenib resistance signature by proteome analysis offers new strategies and rational therapeutic concepts.
abstract: The FDA-approved BRAF inhibitor vemurafenib achieves outstanding clinical response rates in patients with melanoma, but early resistance is common. Understanding the pathologic mechanisms of drug resistance and identification of effective therapeutic alternatives are key scientific challenges in the melanoma setting. Using proteomic techniques, including shotgun analysis and 2D-gel electrophoresis, we identified a comprehensive signature of the vemurafenib-resistant M24met in comparison with the vemurafenib-sensitive A375 melanoma cell line. The resistant cells were characterized by loss of differentiation, induction of transformation, enhanced expression of the lysosomal compartment, increased potential for metastasis, migration, adherence and Ca2(+) ion binding, enhanced expression of the MAPK pathway and extracellular matrix proteins, and epithelial-mesenchymal transformation. The main features were verified by shotgun analysis with QEXACTIVE orbitrap MS, electron microscopy, lysosomal staining, Western blotting, and adherence assay in a VM-1 melanoma cell line with acquired vemurafenib resistance. On the basis of the resistance profile, we were able to successfully predict that a novel resveratrol-derived COX-2 inhibitor, M8, would be active against the vemurafenib-resistant but not the vemurafenib-sensitive melanoma cells. Using high-throughput methods for cell line and drug characterization may thus offer a new way to identify key features of vemurafenib resistance, facilitating the design of effective rational therapeutic alternatives.
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, Austria.
authors.forename: Verena
authors.initials: V
authors.lastname: Paulitschke
authors.affiliation: Institute of Cancer Research and Comprehensive Cancer Center Vienna, Medical University Vienna, Vienna, Austria.
authors.forename: Walter
authors.initials: W
authors.lastname: Berger
authors.affiliation: Institute of Physics, Center for NanoScience, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Paulitschke
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, Austria.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Hofstätter
authors.affiliation: Protein Informatics Group, Department of Statistics, University of Oxford, Oxford, United Kingdom.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Knapp
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, Austria.
authors.forename: Ruth
authors.initials: R
authors.lastname: Dingelmaier-Hovorka
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, Austria.
authors.forename: Dagmar
authors.initials: D
authors.lastname: Födinger
authors.affiliation: Department of Clinical Pharmacy and Diagnostics, University of Vienna, Vienna, Austria.
authors.forename: Walter
authors.initials: W
authors.lastname: Jäger
authors.affiliation: Department of Medical and Chemical Laboratory Diagnostics, Medical University of Vienna, Vienna, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Szekeres
authors.affiliation: Institute of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Meshcheryakova
authors.affiliation: Institute of Analytical Chemistry, University of Vienna, Vienna, Austria.
authors.forename: Andrea
authors.initials: A
authors.lastname: Bileck
authors.affiliation: Institute of Cancer Research and Comprehensive Cancer Center Vienna, Medical University Vienna, Vienna, Austria.
authors.forename: Christine
authors.initials: C
authors.lastname: Pirker
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, Austria.
authors.forename: Hubert
authors.initials: H
authors.lastname: Pehamberger
authors.affiliation: Institute of Analytical Chemistry, University of Vienna, Vienna, Austria.
authors.forename: Christopher
authors.initials: C
authors.lastname: Gerner
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, Austria. rainer.kunstfeld@meduniwien.ac.at.
authors.forename: Rainer
authors.initials: R
authors.lastname: Kunstfeld
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic / Q000187:drug effects / Q000235:genetics; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D058750:Epithelial-Mesenchymal Transition / Q000187:drug effects / Q000235:genetics; D005260:Female; D006801:Humans; D007211:Indoles / Q000494:pharmacology* / Q000627:therapeutic use*; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000235:genetics; D008545:Melanoma / Q000188:drug therapy / Q000235:genetics; D020543:Proteome / Q000235:genetics*; D040901:Proteomics / Q000379:methods; D048493:Proto-Oncogene Proteins B-raf / Q000037:antagonists & inhibitors; D013449:Sulfonamides / Q000494:pharmacology* / Q000627:therapeutic use*; D000077484:Vemurafenib; D023041:Xenograft Model Antitumor Assays
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D007211:Indoles; D020543:Proteome; D013449:Sulfonamides; D000077484:Vemurafenib; D048493:Proto-Oncogene Proteins B-raf