Higher frequency of cagA EPIYA-C Phosphorylation Sites in H. pylori strains from first-degree relatives of gastric cancer patients Full Text
BMC Gastroenterology, 08/20/2012
Queiroz DMM et al. – The authors demonstrated that relatives of gastric cancer patients are more frequently colonized by the most virulent H. pylori cytotoxin associated gene (cagA) and vacuolating cytotoxin gene (vacA) genotypes, which may contribute to increase the risk of gastric cancer.Methods
- The authors evaluated prospectively the prevalence of the infection by more virulent H. pylori strains in 60 relatives of gastric cancer patients comparing the results with those obtained from 49 patients without family histories of gastric cancer.
- H. pylori status was determined by the urease test, histology and presence of H. pylori ureA.
- The cytotoxin associated gene (cagA), the cagA–EPIYA and vacuolating cytotoxin gene (vacA) were typed by PCR and the cagA EPIYA typing was confirmed by sequencing.
- The gastric cancer relatives were significant and independently more frequently colonized by H. pylori strains with higher numbers of CagA–EPIYA–C segments (OR=4.23, 95%CI=1.53––11.69) and with the most virulent s1m1 vacA genotype (OR=2.80, 95%CI=1.04––7.51).
- Higher numbers of EPIYA–C segments were associated with increased gastric corpus inflammation, foveolar hyperplasia and atrophy.
- Infection by s1m1 vacA genotype was associated with increased antral and corpus gastritis.