The Association of cagA, vacA, babA۲, babB and oipA of Helicobacter pylori with Risk of Gastric Carcinoma Development

Background & Objective: Helicobacter pylori (H. pylori), carried by more than half of the world population, is a major cause of chronic duodenal and gastric ulcers, gastritis and carcinoma. Colonization and toxin production include major virulence traits of H. pylori. The aim of this study was to assess the existence of H. pylori and virulence factors among patients with risk of gastrointestinal carcinoma (GC) in an Iraqi population. Materials & Methods: During May ۲۰۱۶- October ۲۰۲۰ in Babylon, Iraq, a total of ۵۰۰ biopsy samples were obtained from gastric tissue of patients with GC, gastritis, duodenitis, duodenal ulcer and gastric ulcer and cultured onto the Brucella agar. H. pylori isolates were identified using conventional biochemical and molecular tests. Molecular identification was conducted by amplification of glmM gene using the polymerase chain reaction (PCR) technique. The adhesin (babA۲, babB and oipA) and toxin (cagA and vacA) genes were also amplified using PCR technique. Results: Among ۵۰۰ biopsy samples, ۲۶۹ (۱۱۰ from males and ۱۵۹ from female patients) H. pylori isolates were identified. The age range of patients was ۱۴-۶۹ years (mean age=۴۷.۳۴±۷.۲۳). The babA۲ and babB genes were detected in ۵۹.۴۷% and ۵۹.۱۰% of isolates, respectively. Notably, babA۲ was observed in ۸۹% of GC and ۶۴% of DN strains being significantly more associated with GC and DN (<۰.۰۰۰۱ and ۰.۰۲۸, respectively). Furthermore, babB-positive strains were significantly (۰.۰۴۲) more associated with PG. The rate of cagA and vacA was ۴۴.۶۰% and ۴۸.۳۲%, respectively. The cagA was detected in ۶۴.۷۳% of GC, and ۱۰۰% of PG and DN strains with a significant association. We detected the oipA in ۵۸.۳۶% of strains which was significantly associated with GC (۷۴%, P=۰.۰۰۰۱), PG (۸۸%, p<۰.۰۰۰۱) and DN (۸۴%, p<۰.۰۰۰۱) as compared to oipA-negative strains. Conclusion: The existence of H. pylori babA۲, cagA and oipA virulence genes was associated with GC, DN and PG. As these genes play a crucial role in the development of gastric carcinoma, accurate control measure toward hindering the colonization of pathogenic strains is essential.