Helicobacter pylori strains carrying the cagA gene are associated with severe disease outcomes, most notably gastric cancer. CagA protein is delivered into gastric epithelial cells by a type IV secretion system. The translocated CagA undergoes tyrosine phosphorylation at the C-terminal EPIYA motifs by host cell kinases. Tyrosine-phosphorylated CagA acquires the ability to interact with and acti...

BACKGROUND Infection with Helicobacter pylori is a major risk factor for the development of atrophic gastritis and gastric cancer. H. pylori strains can differ with respect to the presence of cagA (cytotoxin-associated gene A), a gene encoding a high-molecular-weight immunodominant antigen. H. pylori strains possessing cagA have been associated with enhanced induction of acute gastric inflammat...

Helicobacter pylori induces activation of mitogen-activated protein kinases (MAPKs). However, its effect on H. pylori-induced apoptosis has not been evaluated. Thus, we examined whether H. pylori-induced extracellular signal-regulated kinase 1 and 2 (ERK1/2) and p38 MAPK activation affects gastric epithelial cell apoptosis and bcl-2 family gene expression, especially in relation to the cagA sta...

conclusions using the pcr-rflp method, three distinctive h. pylori caga genotypes were detected in antral biopsies. genotype i, which was predominant among the isolates, was significantly associated with gastritis. however, the data showed that caga genotype iii may play a role in duodenitis and duodenal ulcers in patients infected with h. pylori. patients and methods a total of 161 gastric bio...

Objective(s):Helicobacter pylori infection occurs worldwide, but the prevalence of this infection varies greatly among different countries and population groups. The aim of this study was to determine the seroprevalence of anti-Helicobacter pylori and anti-cytotoxin-associated gene A (CagA) antibodies in asymptomatic healthy population in the center of Iran and to investigate the relation with ...

Helicobacter pylori cagA-positive strain delivers the CagA oncoprotein into gastric epithelial cells and at the same time elicits stomach inflammation. To experimentally investigate the pathophysiological interplay between CagA and inflammation, transgenic mice systemically expressing the bacterial cagA gene were treated with a colitis inducer, dextran sulfate sodium (DSS). Compared with contro...

Infection with CagA-positive Helicobacter pylori is associated with the development of gastric adenocarcinoma. The CagA gene product CagA is injected directly from the bacterium into the bacterium-attached gastric epithelial cells via the type-IV secretion system. Upon membrane localization and subsequent tyrosine phosphorylation by Src family kinases, CagA functions as a scaffolding adaptor an...

BACKGROUND Helicobacter pylori is a vertically inherited gut commensal that is carcinogenic if it possesses the cag pathogenicity island (cag PaI); infection with H.pylori is the major risk factor for gastric cancer, the second leading cause of death from cancer worldwide (WHO). The cag PaI locus encodes the cagA gene, whose protein product is injected into stomach epithelial cells via a Type I...

Colonization of the mucosa of the stomach and the duodenum by Helicobacter pylori is the major cause of acute and chronic gastroduodenal pathologies in humans. Duodenal ulcer formation strongly correlates with the expression of an antigen (CagA) that is usually coeexpressed with the vacuolating cytotoxin (VacA), a protein that causes ulceration in the stomach of mice. However, the relationship ...

BACKGROUND/AIMS Infection with Helicobacter pylori strains harbouring the cagA gene (cagA+) is associated with an increased risk of developing peptic ulcer and gastric cancer. The aim of this study was to assess whether H pylori isolates with different cagA status were present in patients with non-ulcer dyspepsia, and whether a variable cagA status is relevant to histological gastric mucosal da...