Cyclooxygenase-2 expression determines neo-angiogenesis in gallbladder carcinomas.
Neo-angiogenesis may have an important role in the poor prognosis of gallbladder carcinoma. An enhanced expression of COX-2 was found in precancerous lesions and in gallbladder carcinoma, likely to be involved in carcinogenesis as well as in angiogenesis. To study the relationships between the COX-2 expression and degree of vascularization, as well as to evaluate their role in the prognosis of patients with gallbladder carcinoma. 27 cases of gallbladder adenocarcinoma were included, classified grading I-III according the WHO classification. The COX-2 and endothelial antigen CD105 expressions were assessed immunohistochemically. COX-2 expression was evaluated according to the percentage and staining intensity of positive cells into "COX-2 positive" and "COX-2 negative" groups. In order to assess tumor microvessel density (MVD), CD105 positively stained microvessels were counted for each specimen in predominantly vascular areas (hot spots) at 200 x magnification. The MVD ranged from 9 to 46 microvessels/field. 15 tumors belonged to the hypervascular group (MVD > or = 25) and 12 to the hypovascular group. There were 16 (59.2%) COX-2 positive cases. There was difference in the degree of angiogenesis between COX-2 positive vs. COX-2 negative group: 11 (68.8%) out of 16 "COX-2 positive" tumors were hypervascular, in comparison with just 4 (36.4%) of "COX-2 negative" tumors. Our data show that the MVD corresponds to the COX-2 overexpression in gallbladder carcinomas. Augmented tumor neovascularization induced by COX-2 might be responsible for the poor prognosis in gallbladder carcinoma patients.
Legan
Mateja
M
Institute of Histology and Embryology, Faculty of Medicine, University of Ljubljana, Korytkova 2, 1000 Ljubljana, Slovenia.
Luzar
Bostjan
B
Ferlan-Marolt
Vera
V
Cör
Andrej
A
D000230:Adenocarcinoma / Q000098:blood supply / Q000201:enzymology* / Q000473:pathology*; D000368:Aged; D015703:Antigens, CD / Q000096:biosynthesis / Q000235:genetics; D051546:Cyclooxygenase 2 / Q000096:biosynthesis*; D000071063:Endoglin; D005260:Female; D005706:Gallbladder Neoplasms / Q000098:blood supply / Q000201:enzymology* / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000201:enzymology* / Q000473:pathology*; D011956:Receptors, Cell Surface / Q000096:biosynthesis / Q000235:genetics; D012039:Regional Blood Flow / Q000502:physiology; D012189:Retrospective Studies
D015703:Antigens, CD; C064206:ENG protein, human; D000071063:Endoglin; D011956:Receptors, Cell Surface; D051546:Cyclooxygenase 2