AIM： To examine the relationship between cyclooxygenase-2 （COX-2） overexpression and p53 accumulation in gallbladder carcinoma and its precursor lesions.METHODS： Sixty-eight gallbladder tissue samples comprising 1...AIM： To examine the relationship between cyclooxygenase-2 （COX-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 epite hlium, 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 2d （87.5%） of high- grade dysplasia （P = 0.019）. Accumulation of p53 was detected in 5 （32.2%） cases of high-grade dysplasia and in 23 （48.2%） of carcinomas. No p53 accumulation was found in normal epithelium or low-grade dysplasia. COX-2 overexpression was observed in 27 of 28 （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.展开更多
文摘AIM： To examine the relationship between cyclooxygenase-2 （COX-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 epite hlium, 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 2d （87.5%） of high- grade dysplasia （P = 0.019）. Accumulation of p53 was detected in 5 （32.2%） cases of high-grade dysplasia and in 23 （48.2%） of carcinomas. No p53 accumulation was found in normal epithelium or low-grade dysplasia. COX-2 overexpression was observed in 27 of 28 （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.
