In situ quantitative study of BAG-1 and BAD in extrahepatic cholangiocarcinoma

Abstract

AIM: To detect the expression of apoptosis related proteins BAG-1 and BAD and to investigate their functions of apoptosis modulation and relations to tumor differentiation in extrahepatic cholangiocarcinoma. METHODS: Quantitative in situ methods of DAKO Envision TM Systems immunohistochemistry in combination with computerassisted image analysis and apoptotic cells counting were used to observe the expression levels of BAG-1 and BAD and the apoptosis indexes in 42 cases of extrahepatic cholangiocarcinoma. RESULTS: The expression levels of BAG-1 and BAD were measured with average absorbance (A) derived from the quantitative image analysis. Among 24, 13 and 5 cases of well, moderately and poorly differentiated extrahepatic cholangiocarcinomas, the average A of BAG-1 was respectively 0.068±0.037, 0.112±0.057 and 0.152±0.062, of BAD was respectively 0.079±0.053, 0.138±0.058 and 0.165±0.061, and the apoptotic indexes examined in the hematoxylinand-eosin-stained specimens were respectively 1.1±0.5, 1.7±0.3 and 3.5±1.3. The expression levels of BAG-1 and BAD and the apoptotic indexes were increased obviously from well, moderately to poorly differentiated extrahepatic cholangiocarcinoma (P <0.05). The expression level of BAD was correlated to the apoptotic indexes (P <0.01). CONCLUSION: Expressions of BAG-1 and BAD and apoptosis indexes were all associated with differentiation of extrahepatic cholangiocarcinoma. BAG-1 and BAD may take part in the apoptosis modulation of the tumor.