Role of Proteinase-Activated Receptor-2 on Cyclooxygenase-2 Expression in H. pyloriInfected Gastric Epithelial Cells
Proteinase-activated receptor-2 (PAR-2) belongs to a novel subfamily of G proteincoupled receptors with seven-transmembrane domains. PAR-2 is activated by serine proteases, such as trypsin, mast cell tryptase, and allergic or bacterial proteases. The presence of trypsin has been shown in human stomach. Cyclooxygenase-2 (COX-2) is induced by inflammatory cytokines, growth factors, gastrin, and reactive oxygen species in gastric epithelial cells, which may lead to mutagenesis and subsequent metaplasia, dysplasia, and cancer formation. We investigated whether PAR-2 is activated in H. pylori (HP99)-infected cells, which is related to COX-2 induction in gastric epithelial cells. After treatment of H. pylori to AGS (gastric adenocarcinoma) cells at a bacteria/cell ratio of 10
proteinase-activated receptor-2 cyclooxygenase-2 helicobacter pylori