Prevalence of Human Papillomavirus Infection in Gastric Cancer in Ardebil Province, Northwest of Iran

Human papillomavirus (HPV) is considered to be the important viral agent associated with several human cancers, the most important of which is cervical cancer. Today, the role of this virus in gastrointestinal cancers, including gastric cancer (GC), has also been considered. This study performed to clarify the possible association of HPV and the occurrence of GC in Ardabil province, Northwest Iran, which is a high-risk area.

The study involved 140 paraffin-embedded specimens of gastric tissue that divided into two groups based on the pathological diagnosis: 70 patients with GC as the case group and 70 samples without a diagnosed tumor in gastric tissue as control. The nested polymerase chain reaction (Nested-PCR) method was carried out to detect the HPV genome in paraffin embedded gastric tissue samples. Finally, samples that were positive for the presence of the HPV genome were sequenced to determine the type of virus.

HPV genome was detected in 33 (47.14%) of 70 gastric cancer samples and 4.28% (3/70) of samples without gastric cancer. In case and control groups 97% and 67% of HPV positive samples were over 40 years old, respectively and the number of men was more than women. Ultimately, HPV-16 and HPV-18 were detected in PCR positive samples by sequence analysis.

Based on our founding, the infection rate of HPV in patients with gastric cancer was significantly higher than that in non-cancerous samples of gastric tissue. Moreover, high-risk types of HPV (16, 18) were detected in all positive samples. Therefore, the results of this investigation suggest that HPV can be one of the possible risk factors for the occurrence of gastric cancer in Ardabil province.