Presence of cagA Gene in Patients with Gastric Cancer and Gastritis with Helicobacter pylori Infection

Background and purpose: Helicobacter pylori is a gram-negative, micro-aerophilic, and spiral-shaped bacillus. Infection with this bacterium can lead to gastritis, ulcers, and even gastric cancer. This study was conducted to evaluate the presence of the cagA gene among patients with gastritis and gastric cancer. Materials and methods: This study was performed in patients with gastritis (n=40) and gastric cancer (n=40). Presence of H. pylori infection in gastritis specimens and in cancerous tissues was investigated by urease test and Giemsa staining, respectively. Using PCR, 16S rRNA and cagA genes were investigated. Results: Pain and weight loss were the most common complaints of patients. Dyspepsia and duodenal ulcer were the most frequent endoscopic findings. According to pathologic results, intestinal-type G1 adenocarcinoma was detected in most cases. All positive-H. pylori cases were also positive for 16S rRNA. The cagA gene in patients with gastritis and stomach cancer was present in 13 (32.5%) and 11 (27.5%) cases, respectively. Conclusion: Compared to other studies, low presence of the cagA gene in Qom could be an indication of less virulent strains in this province, but, further studies are recommended to evaluate other genes.