Evaluation of Mutations in 23S rRNA genes of Helicobacter pylori in Paraffin-Embedded Gastric Biopsy Specimens from Iranian Gastric Cancer and Gastritis Patients

Evaluation of Mutations in 23S rRNA genes of Helicobacter pylori in Paraffin-Embedded Gastric Biopsy Specimens from Iranian Gastric Cancer and Gastritis Patients
tahereh ebrahimi,¹ vahideh tarhriz,^2,* shirin eyvazi,³ parivar yazdani,⁴
1. Department of Nano-Biotechnology, Pasteur Institute of Iran, Tehran, Iran
2. Molecular Medicine Research Center, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
3. Department of Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
4. Molecular Medicine Research Center, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
Introduction: Helicobacter pylori (H. pylori) infection is considered as one of the main causes of gastric cancer. Treatment failure of the infection often occurs due to antibiotic resistance. Herein, we aimed to evaluate the mutations in 23S rRNA gene of H. pylori which are associated with clarithromycin resistance, in paraffin-embedded gastric biopsies from patients with gastric adenocarcinoma and gastritis in Tabriz, the northwest of Iran.
Methods: In the study, 80 paraffin-embedded tissue sections from 40 gastric cancer and 40 gastritis patients in the Imam Reza hospital, Tabriz, Iran were collected. The existence of ureC gene was verified by PCR method. Genotypical clarithromycin resistance was investigated by Real time PCR method and determination of the melting temperature
Results: The results of ureC amplification showed that DNA of H. pylori was present in the 82.66% of the obtained DNA samples. About 45.16% of samples were resistant to the clarithromycin. Based on the results from Real time PCR, the frequency of mutations was as follow A2143G 64.28%, A2142G 44.44% and A2142C 1.11%.
Conclusion: A2143G mutation is the most frequent mutation among clarithromycin resistant genes in Iran. Screening for this mutation could help researchers to investigate the most effective anti-H. pylori antibiotics and to prevent antibiotic resistance.
Keywords: Gastric cancer, H. pylori, clarithromycin resistance