title: Immunohistochemical detection of receptor tyrosine kinases c-kit, EGF-R, and PDGF-R in colorectal adenocarcinomas.
abstract: OBJECTIVE
  The selective inhibition of tyrosine kinases is a promising strategy in the treatment of several human malignancies. This study aimed to clarify expression patterns of therapeutically addressable receptor tyrosine kinases in colorectal cancer.
  
  
  METHODS
  In this study, we used tissue arrays to analyze 263 specimen of colorectal carcinoma for the expression of the tyrosine kinases c-kit (CD117), epidermal growth factor receptor (EGF-R), and platelet-derived growth factor receptor (PDGF-R). Staining patterns were then correlated with tumor stage and survival.
  
  
  RESULTS
  Five tumors (1.9%) showed a strong expression of c-kit (CD117), while in 40 samples (15.2%), a weak/intermediate expression was observed. Positive staining did not correlate with histopathological parameters although a trend toward a better survival of c-kit-positive patients was observed. No positivity for PDGF-R was observed in 263 samples of colorectal carcinomas. Positive EGF-R expression was identified in 39 cases (15.2%), whereas 218 samples (84.8%) stained negative.
  
  
  CONCLUSIONS
  Our study confirms that expression of the tyrosine kinases c-kit and PDGF-R are rare in colorectal carcinomas and do not correlate with tumor stage.
authors.affiliation: Department of Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany. janfriederichs@gmx.de
authors.forename: Jan
authors.initials: J
authors.lastname: Friederichs
authors.forename: Claus W H
authors.initials: CW
authors.lastname: von Weyhern
authors.forename: Robert
authors.initials: R
authors.lastname: Rosenberg
authors.forename: Dietrich
authors.initials: D
authors.lastname: Doll
authors.forename: Raymonde
authors.initials: R
authors.lastname: Busch
authors.forename: Florian
authors.initials: F
authors.lastname: Lordick
authors.forename: Jörg Rüdiger
authors.initials: JR
authors.lastname: Siewert
authors.forename: Mario
authors.initials: M
authors.lastname: Sarbia
mesh_terms: D000230:Adenocarcinoma / Q000276:immunology*; D015179:Colorectal Neoplasms / Q000276:immunology*; D066246:ErbB Receptors / Q000096:biosynthesis*; D006801:Humans; D007150:Immunohistochemistry; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis*; D017479:Receptors, Platelet-Derived Growth Factor / Q000096:biosynthesis*; D046888:Tissue Array Analysis
chemical_list: D066246:ErbB Receptors; D019009:Proto-Oncogene Proteins c-kit; D017479:Receptors, Platelet-Derived Growth Factor