Expression of angiopoietin-1, 2 and 4 and Tie-1 and 2 in gastrointestinal stromal tumor, leiomyoma and schwannoma.
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.
Nakayama
Toshiyuki
T
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
Inaba
Maki
M
Naito
Shinji
S
Mihara
Yumi
Y
Miura
Shiro
S
Taba
Mitsuru
M
Yoshizaki
Ayumi
A
Wen
Chun-Yang
CY
Sekine
Ichiro
I
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
D042683:Angiopoietin-1; D042702:Angiopoietin-2; D042682:Angiopoietins; C118117:angiopoietin 4; D042810:Receptor, TIE-1; D042787:Receptor, TIE-2