Author/Editor     Legan, Mateja; Luzar, Boštjan; Ferlan-Marolt, Vera; Coer, Andrej
Title     Expression of cyclooxygenase-2 is associated with p53 accumulation in premalignant and malignant gallbladder lesions
Type     članek
Source     World J Gastroenterol
Vol. and No.     Letnik 12, št. 21
Publication year     2006
Volume     str. 3425-9
Language     eng
Abstract     Aim: To examine the relationship between cyclooxygenase-2 (CGX-2) overexpression and p53 accumulation in gallbladder carcinoma and its precursor lesions. Methods: Sixty-eight gallbladder tissue samples comprising 14 cases of normal gallblader epithelium, 27 cases of dysplasia (11 low-grade dyplasia and 16 high-grade dysplasia) and 27 adenocarcinomas were evaluated by immunohistochemistry for COX-2 expression and p53 accumulation. The relationship among COX-2 expression, p53 accumulation and clinicopathological characteristics was analysed. Results: COX-2 was expressed in 14.3% of normal gallbladder epithelium, 70.3% of dysplastic epithelium, and 59.2% of adenocarcinomas. When divided into low- and high-grade dysplasia, COX-2 was positive in 5 (45.4%) cases of low-grade and 14 (87.5%) of highgrade dysplasia (P = 0.019). Accumulation of p53 was detected in 5 (31.2%) cases of high-grade dysplasia and in 13 (48.1%) of carcinomas. No p53 accumulation was found in normal epithelium or low-grade dysplasia. COX-2 overexpression was observed in 17 of 18 (94.4%) cases with p53-accumulation in comparison with 20 (40.0%) out of 50 cases without p53 accumulation (P < 0.001). Conclusion: The significant differences in COX-2 expression among normal epithelium, low-grade dysplasia and high-grade dysplasia suggest that overexpression of COX-2 enzyme is an early event in gallbladder carcinogenensis. Furthermore, since accumulation of p53 correlates with COX-2 expression, COX-2 overexpression observed in gallbladder high-grade dysplasia and carcinoma might be partly due to the dysfunction of p53.
Descriptors     GALLBLADDER NEOPLASMS
PROSTAGLANDIN-ENDOPEROXIDE SYNTHASE
PROTEIN P53
ADENOCARCINOMA
IMMUNOHISTOCHEMISTRY
RETROSPECTIVE STUDIES