title: Immunohistochemical analysis of receptor tyrosine kinase signal transduction activity in chordoma.
abstract: OBJECTIVE
  Currently, there are no effective chemotherapeutic protocols for chordoma. Reports of receptor tyrosine kinase (RTK) expression in chordoma suggest that these tumours may respond to kinase inhibitor therapy. However, RTK signalling activity has not been extensively investigated in chordoma.
  
  
  METHODS
  A tissue microarray containing 21 cases of chordoma was analysed for expression of a number of proteins involved in signal transduction from RTKs by immunohistochemistry.
  
  
  RESULTS
  Platelet-derived growth factor receptor-beta, epidermal growth factor receptor (EGFR), KIT and HER2 were detected in 100%, 67%, 33% and 0% of cases, respectively. Platelet-derived growth factor receptor-beta staining was of moderate-to-strong intensity in 20 of 21 cases. In contrast, KIT immunoreactivity was weak and focal in each of the seven positive cases. Total EGFR staining was variable; weak staining for phosphorylated EGFR was detected in nine cases. Phosphorylated isoforms of p44/42 mitogen-activated protein kinase, Akt and STAT3, indicative of tyrosine kinase activity, were detected in 86%, 76% and 67% of cases, respectively.
  
  
  CONCLUSIONS
  Chordomas commonly express RTKs and activated signal transduction molecules. Although there were no statistically significant correlations between the expression of any of the markers studied and disease-free survival or tumour location, the results nonetheless indicate that chordomas may respond to RTK inhibitors or modulators of other downstream signalling molecules.
authors.affiliation: Department of Pathology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Fasig
authors.forename: W D
authors.initials: WD
authors.lastname: Dupont
authors.forename: B J
authors.initials: BJ
authors.lastname: LaFleur
authors.forename: S J
authors.initials: SJ
authors.lastname: Olson
authors.forename: J M M
authors.initials: JM
authors.lastname: Cates
mesh_terms: D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000201:enzymology*; D002817:Chordoma / Q000201:enzymology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D046888:Tissue Array Analysis
chemical_list: D020794:Receptor Protein-Tyrosine Kinases