BACKGROUND AND AIMS: Bcl-2 protein prolongs cell survival in the face of classical apoptotic stimuli, and is considered to be a suppressor of apoptosis. Bax plays a key role in apoptosis by accelerating cell death after an apoptotic stimulus. The aim of our study was to determine the roles of the Bax proapoptotic gene and the Bcl-2 antiapoptotic gene in the carcinogenesis of gastric cancer. METHODS: One hundred and forty-five gastric biopsy specimens of chronic gastritis, atrophic gastritis, intestinal metaplasia and gastric dysplasia were studied. Using immunohistochemical methods, Bax and Bcl-2 protein expression was observed. RESULTS: Bax was expressed in epithelial cells in all cases of chronic gastritis. Bax was not detected in 26% of specimens of atrophic gastritis. As intestinal metaplasia develops, Bax is further suppressed. In biopsy samples with dysplasia, Bax expression was demonstrated only in 12% of biopsy samples. Although Bcl-2 protein was not detected in chronic gastritis, aberrant expression was found in gastric epithelial intestinal metaplasia and dysplasia. CONCLUSIONS: The suppression of Bax and overexpression of Bcl-2 protein is an early event in gastric tumorigenesis, before gastric dysplastic changes occur.
BACKGROUND AND AIMS: Bcl-2 protein prolongs cell survival in the face of classical apoptotic stimuli, and is considered to be a suppressor of apoptosis. Bax plays a key role in apoptosis by accelerating cell death after an apoptotic stimulus. The aim of our study was to determine the roles of the Bax proapoptotic gene and the Bcl-2 antiapoptotic gene in the carcinogenesis of gastric cancer. METHODS: One hundred and forty-five gastric biopsy specimens of chronic gastritis, atrophic gastritis, intestinal metaplasia and gastric dysplasia were studied. Using immunohistochemical methods, Bax and Bcl-2 protein expression was observed. RESULTS:Bax was expressed in epithelial cells in all cases of chronic gastritis. Bax was not detected in 26% of specimens of atrophic gastritis. As intestinal metaplasia develops, Bax is further suppressed. In biopsy samples with dysplasia, Bax expression was demonstrated only in 12% of biopsy samples. Although Bcl-2 protein was not detected in chronic gastritis, aberrant expression was found in gastric epithelial intestinal metaplasia and dysplasia. CONCLUSIONS: The suppression of Bax and overexpression of Bcl-2 protein is an early event in gastric tumorigenesis, before gastric dysplastic changes occur.
Authors: R Rosania; M Varbanova; T Wex; C Langner; J Bornschein; F Giorgio; E Ierardi; P Malfertheiner Journal: BMC Gastroenterol Date: 2017-06-29 Impact factor: 3.067