title: Expression of angiopoietin-1, 2 and 4 and Tie-1 and 2 in gastrointestinal stromal tumor, leiomyoma and schwannoma.
abstract: OBJECTIVE
  To investigate the role of angiopoietin (Ang) -1, -2 and -4 and its receptors, Tie-1 and -2, in the growth and differentiation of gastrointestinal stromal tumors (GISTs).
  
  
  METHODS
  Thirty GISTs, seventeen leiomyomas and six schwannomas were examined by immunohistochemistry in this study.
  
  
  RESULTS
  Ang-1, -2 and -4 proteins were expressed in the cytoplasm of tumor cells, and Tie-1 and -2 were expressed both in the cytoplasm and on the membrane of all tumors. Immunohistochemical staining revealed that 66.7% of GISTs (20 of 30), 76.5% of leiomyomas (13 of 17) and 83.3% of schwannomas (5 of 6) were positive for Ang-1. 83.3% of GISTs (25 of 30), 82.4% of leiomyomas (14 of 17) and 100% of schwannomas (6 of 6) were positive for Ang-2. 36.7% of GISTs (11 of 30), 58.8% of leiomyomas (10 of 17) and 83.3% of schwannomas (5 of 6) were positive for Ang-4. 60.0% of GISTs (18 of 30), 82.4% of leiomyomas and 100% of schwannomas (6 of 6) were positive for Tie-1. 10.0% of GISTs (3 of 30), 94.1% of leiomyomas (16 of 17) and 33.3% of schwannomas (2 of 6) were positive for Tie-2. Tie-2 expression was statistically different between GISTs and leiomyomas (P < 0.001). However, there was no correlation between expression of angiopoietin pathway components and clinical risk categories.
  
  
  CONCLUSIONS
  Our results suggest that the angiopoietin pathway plays an important role in the differentiation of GISTs, leiomyomas and schwannomas.
authors.affiliation: Department of Tumor and Diagnostic Pathology, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki, Japan. toshi-n@nagasaki-u.ac.jp
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Nakayama
authors.forename: Maki
authors.initials: M
authors.lastname: Inaba
authors.forename: Shinji
authors.initials: S
authors.lastname: Naito
authors.forename: Yumi
authors.initials: Y
authors.lastname: Mihara
authors.forename: Shiro
authors.initials: S
authors.lastname: Miura
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Taba
authors.forename: Ayumi
authors.initials: A
authors.lastname: Yoshizaki
authors.forename: Chun-Yang
authors.initials: CY
authors.lastname: Wen
authors.forename: Ichiro
authors.initials: I
authors.lastname: Sekine
mesh_terms: D042683:Angiopoietin-1 / Q000032:analysis*; D042702:Angiopoietin-2 / Q000032:analysis*; D042682:Angiopoietins / Q000032:analysis*; D005770:Gastrointestinal Neoplasms / Q000737:chemistry / Q000145:classification / Q000473:pathology; D046152:Gastrointestinal Stromal Tumors / Q000737:chemistry* / Q000473:pathology; D041981:Gastrointestinal Tract / Q000737:chemistry / Q000473:pathology; D006801:Humans; D007889:Leiomyoma / Q000737:chemistry* / Q000473:pathology; D009442:Neurilemmoma / Q000737:chemistry* / Q000473:pathology; D042810:Receptor, TIE-1 / Q000032:analysis*; D042787:Receptor, TIE-2 / Q000032:analysis*; D015398:Signal Transduction; D013223:Statistics as Topic
chemical_list: D042683:Angiopoietin-1; D042702:Angiopoietin-2; D042682:Angiopoietins; C118117:angiopoietin 4; D042810:Receptor, TIE-1; D042787:Receptor, TIE-2