Immunohistochemical analysis of pro-apoptotic PUMA protein and mutational analysis of PUMA gene in gastric carcinomas

BackgroundMounting evidence indicates that alteration of apoptosis is involved in the mechanisms of cancer development. PUMA, a pro-apoptotic member of Bcl-2 family, mediates p53-dependent and -independent apoptosis.AimThe aim of this study was to explore whether alteration of PUMA protein expression is a characteristic of human gastric carcinomas.Patients and methodsWe analysed expression of PUMA protein in 60 gastric adenocarcinomas by immunohistochemistry. Also, we examined PUMA gene mutation in the same tissues by a single-strand conformation polymorphism.ResultsPUMA protein expression was detected in 44 cases (73%) of the 60 gastric carcinomas, whereas it was not detected in normal gastric mucosal epithelial cells. The mutational analysis revealed no PUMA mutation in the gastric carcinomas.ConclusionsOur data suggest that PUMA mutation is not a direct target of inactivation in gastric tumourigenesis. Also, increased expression of PUMA in malignant gastric epithelial cells compared with normal mucosal epithelial cells suggested that PUMA expression may play a role in gastric tumourigenesis.