Evaluation of Helicobacter Pylori and NapA Gene in Paraffin Blocks of Gastric Adenocarcinoma Tissues from Pathology Bank of Shahid Beheshti Hospital, Qom, Iran (2011-2017)
Abstract
Objective: Helicobacter pylori is a known cause of gastrointestinal diseases such as gastritis, gastric ulcers and in severe cases of gastric cancer. Neutrophil-activating protein (NAP) is one of the important markers in bacterial pathogenesis. The aim of this study was to evaluate the presence of Helicobacter pylori and napA gene in specimens with gastric cancer.
Methods: This study was performed on 67 gastrectomy specimens stored in the pathology ward of Shahid Beheshti Hospital in Qom. The presence of Helicobacter pylori infection in cancerous tissues was evaluated by Giemsa staining. After recording the microscopic data, DNA was extracted from paraffin blocks using a commercial kit. Finally, PCR of 16s rRNA and napA genes were evaluated.
Results: According to pathological evaluation results, forty gastrectomy cases (59.7%) were diagnosed as gastric adenocarcinoma. The mean age ± standard deviation (SD) for the patients was 49.12± 18.54 years and was more prevalent in men. The microscopic examination of the tissues showed that all adenocarcinoma samples were also positive for Helicobacter pylori (100%- 40/40). Intestinal type adenocarcinoma (85%), N1 lymph node metastasis (52.5%), G1 grade (50%), and T2 stage (65%) were the most frequent pathological findings. The results of 16s rRNA gene analysis were in accordance with pathological results and all samples were positive by PCR method as well. All Helicobacter pylori-positive samples had no napA pathogenic gene.
Conclusion: The results showed that cases of gastric adenocarcinoma in Qom were significant and positive cases of Helicobacter pylori infection were high among these samples. In this study, no case of napA positive gene was found. It seems that this gene alone is not an independent factor in tumor development and may be influenced by other virulence factors. Therefore, further research is needed to clarify the issue.