title: EGFR and erbB2 in malignant peripheral nerve sheath tumors and implications for targeted therapy.
abstract: Malignant peripheral nerve sheath tumors (MPNSTs) are sarcomas with poor prognosis and limited treatment options. Evidence for a role of epidermal growth factor receptor (EGFR) and receptor tyrosine kinase erbB2 in MPNSTs led us to systematically study these potential therapeutic targets in a larger tumor panel (n = 37). Multiplex ligation-dependent probe amplification and fluorescence in situ hybridization analysis revealed increased EGFR dosage in 28% of MPNSTs. ERBB2 and three tumor suppressor genes (PTEN [phosphatase and tensin homolog deleted on chromosome 10], CDKN2A [cyclin-dependent kinase inhibitor 2A], and TP53 [tumor protein p53]) were frequently lost or reduced. Reduction of CDKN2A was linked to appearance of metastasis. Comparison of corresponding neurofibromas and MPNSTs revealed an increase in genetic lesions in MPNSTs. No somatic mutations were found within tyrosine-kinase-encoding exons of EGFR and ERBB2. However, at the protein level, expression of EGFR and erbB2 was frequently detected in MPNSTs. EGFR expression was significantly associated with increased EGFR gene dosage. The EGFR ligands transforming growth factor alpha and EGF were more strongly expressed in MPNSTs than in neurofibromas. The effects of the drugs erlotinib and trastuzumab, which target EGFR and erbB2, were determined on MPNST cell lines. In contrast to trastuzumab, erlotinib mediated dose-dependent inhibition of cell proliferation. EGF-induced EGFR phosphorylation was attenuated by erlotinib. Summarized, our data indicate that EGFR and erbB2 are potential targets in treatment of MPNST patients.
authors.affiliation: Institute of Neuropathology, Charité-Universitätsmedizin Berlin, CVK, Augustenburger Platz 1, D-13353 Berlin, Germany. nikola.holtkamp@charite.de
authors.forename: Nikola
authors.initials: N
authors.lastname: Holtkamp
authors.forename: Elke
authors.initials: E
authors.lastname: Malzer
authors.forename: Jan
authors.initials: J
authors.lastname: Zietsch
authors.forename: Ali Fuat
authors.initials: AF
authors.lastname: Okuducu
authors.forename: Jana
authors.initials: J
authors.lastname: Mucha
authors.forename: Christian
authors.initials: C
authors.lastname: Mawrin
authors.forename: Victor-F
authors.initials: VF
authors.lastname: Mautner
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Schildhaus
authors.forename: Andreas
authors.initials: A
authors.lastname: von Deimling
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D016503:Drug Delivery Systems; D004357:Drug Synergism; D004815:Epidermal Growth Factor / Q000235:genetics / Q000378:metabolism; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D000069347:Erlotinib Hydrochloride; D018628:Gene Dosage; D019942:Genes, p16; D016158:Genes, p53; D006801:Humans; D007150:Immunohistochemistry; D018317:Nerve Sheath Neoplasms / Q000235:genetics* / Q000378:metabolism; D051059:PTEN Phosphohydrolase / Q000235:genetics; D018807:Polymorphism, Single-Stranded Conformational; D011799:Quinazolines / Q000494:pharmacology; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016211:Transforming Growth Factor alpha / Q000235:genetics / Q000378:metabolism; D000068878:Trastuzumab
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D000069347:Erlotinib Hydrochloride; D051059:PTEN Phosphohydrolase; D011799:Quinazolines; D018719:Erb-b2 Receptor Tyrosine Kinases; D016211:Transforming Growth Factor alpha; D000068878:Trastuzumab; C508053:ERBB2 protein, human; C494929:PTEN protein, human