DETERMINATION OF HELICOBACTER PYLORI CAGA GENE AND VACA GENOTYPES IN PATIENTS WITH GASTRIC CANCER

Abstract

Background: H. pylori is the first cause of gastric cancer (GC). However, the role of cagA gene and vacA gene in GC is still controversial. This study is aimed at determining the rates of H. pylori infection, cagA gene, vacA genotypes in patients with GC; and evaluating the relationship between cagA gene, vacA genotypes and endoscopic and histopathological features of gastric cancer. Patients and methods: Fifty eight GC patients and one hundred and sixteen non-GC patients (controls) were enrolled. Infection of H. pylori was determined by PCR. cagA gene and vacA genotypes were determined by Multiplex PCR. Results: The rate of H. pylori was found in 55.2% in GC group. The rate of cagA gene and vacA gene in GC patients H. pylori positive were found in 78.1% and 100%, respectively. vac A genotypes s1/m1, s1/m2 and s1/m1m2 were found in 34.4%; 50% and 15.6%, respectively. The risk of GC of cagA positive group was higher than cagA negative group, with OR = 4,5; 95%CI = 1.6-12.2. The risk of GC of vacA s1/m1, cagA positive group was higher than vacA s1/m1, cagA negative group, OR = 7.1; 95%CI = 1.4-36. A statistically significative difference of rate of cagA positive was found between Borrmann III/IV group (100%) and Borrmann I/II group (46.2%). A statistically significative difference of rate of cagA positive was found between the tubular adenocarcinoma group (100%) and signet-ring cell carcinoma (44.4%, p = 0,002), and mucinous adenocarcinoma (50%, p =0,024). Conclusion: Gene cagA and vacA s1/m1 genotype were both risk factors in GC. A significative differences of rate of cagA positive were found between Borrmann groups, and between groups of WHO histopathological classification. Key words: cagA gene and vacA genotype, Helicobacter pylori, gastric cancer