Expression of transforming growth factor-alpha and epidermal growth factor receptor in gastrointestinal stromal tumours.
Activation of epidermal growth factor receptor (EGFR) is associated with cell growth and transformation. Both transforming growth factor-alpha (TGF-alpha) and epidermal growth factor bind to and activate EGFR. We studied the expression of TGF-alpha and two EGFRs (HER-1 and HER-2) in gastrointestinal stromal tumours (GISTs) of the stomach (n = 9) and small intestine (n = 6) using standard immunostaining techniques in paraffin-embedded sections. Most GISTs expressed TGF-alpha, and a few expressed HER-1. All HER-1-positive tumours expressed TGF-alpha. These results suggest that a TGF-alpha/EGFR autocrine loop is present in GIST and that TGF-alpha promotes proliferation of GIST tumour cells through its interaction with HER-1 in at least some GISTs. This is the first description of an autocrine loop in GIST. In contrast, HER-2 is not expressed in any GIST.
Cai
Y C
YC
Department of Pathology, University of Massachusetts Memorial Health Care, Worcester 01655, USA.
Jiang
Z
Z
Vittimberga
F
F
Xu
X
X
Savas
L
L
Woda
B
B
Callery
M
M
Banner
B
B
D000328:Adult; D000368:Aged; D066246:ErbB Receptors / Q000378:metabolism*; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D020033:Protein Isoforms / Q000378:metabolism; D013194:Staining and Labeling; D016211:Transforming Growth Factor alpha / Q000378:metabolism*
D020033:Protein Isoforms; D016211:Transforming Growth Factor alpha; D066246:ErbB Receptors