title: Constitutive activation of neuregulin/ERBB3 signaling pathway in clear cell sarcoma of soft tissue.
abstract: Clear cell sarcoma of soft tissue (CCSST) represents a highly malignant tumor of the musculoskeletal system that is characterized by the chromosomal translocation t(12;22)(q13;q12) of the Ewing sarcoma gene (EWSR1) and activating transcription factor 1 (ATF1). In a former microarray expression study, we identified ERBB3, a member of the epidermal growth factor receptor (EGFR) family, as a promising new diagnostic marker in the differential diagnosis of CCSST. Here we show that, besides ErbB3, all CCSST cell lines (n = 8) also express the ErbB2 receptor or the ErbB4 receptor, representing an adequate coreceptor of ErbB3. The phosphorylation status of ErbB3 revealed these receptor pairs to be either constitutively activated in CCSST cells with high neuregulin-1 (NRG1) expression (n = 4) or activatable by exogenic NRG1 in cells showing low amounts of NRG1 mRNA (n = 4). Exogenous NRG1 stimulated the growth of a subset of CCSST cells but did not affect the kinetics of another subset. This difference was not strictly dependent on endogenous NRG1 expression; however, the growth-inhibiting effect of the pan-ErbB tyrosine kinase inhibitor CI-1033 or PD158780 clearly correlated with NRG1 expression indicating an autocrine growth stimulation loop which may constitute an interesting target of new therapeutic strategies in this tumor entity.
authors.affiliation: Institute of Pathology, Heinrich-Heine-University, Düsseldorf, Germany.
authors.forename: Karl-Ludwig
authors.initials: KL
authors.lastname: Schaefer
authors.forename: Kristin
authors.initials: K
authors.lastname: Brachwitz
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Braun
authors.forename: Raihanatou
authors.initials: R
authors.lastname: Diallo
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Wai
authors.forename: Susanne
authors.initials: S
authors.lastname: Zahn
authors.forename: Dominik T
authors.initials: DT
authors.lastname: Schneider
authors.forename: Cornelius
authors.initials: C
authors.lastname: Kuhnen
authors.forename: Arabel
authors.initials: A
authors.lastname: Vollmann
authors.forename: Gero
authors.initials: G
authors.lastname: Brockhoff
authors.forename: Helmut E
authors.initials: HE
authors.lastname: Gabbert
authors.forename: Christopher
authors.initials: C
authors.lastname: Poremba
mesh_terms: D000483:Alleles; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007700:Kinetics; D020890:Neuregulin-1 / Q000378:metabolism*; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis; D009841:Oligonucleotides / Q000737:chemistry; D010766:Phosphorylation; D011743:Pyrimidines / Q000494:pharmacology; D020893:Receptor, ErbB-3 / Q000378:metabolism*; D018227:Sarcoma, Clear Cell / Q000378:metabolism*; D015398:Signal Transduction; D012983:Soft Tissue Neoplasms / Q000378:metabolism*
chemical_list: C107875:6-(methylamino)pyrido(3,4-d)pyrimidine; D020890:Neuregulin-1; D009841:Oligonucleotides; D011743:Pyrimidines; D020893:Receptor, ErbB-3