Analysis of Colorectal Cancer and Polyps for the Presence of Herpes Simplex Virus and Epstein - Barr virus DNA Sequences by Polymerase Chain Reaction

Background: Colorectal cancer is one of the most common malignancies worldwide with more than one million new cases diagnosed each year . The aim of this study is to investigate the prevalence of herpes simplex virus and Epstein-Barr virus in patients with colorectal carcinomas and polyps in comparison with healthy subjects by using the polymerase chain reaction technique.Methods: In this analytical case-control study, we selected ۱۵ patients with colorectal cancer , ۲۰ patients with colorectal polyps and ۳۵ patients without malignancy as controls. Biopsy specimens were frozen under sterile conditions at -۲۰ºC. After DNA extraction, analysis of polymerase chain reaction to detect herpes simplex virus and Epstein-Barr virus DNA in tissue samples was performed. Statistical analysis was performed with the χ۲ test.Results: We observed herpes simplex DNA in ۳۳.۳% of tumor samples (۵ of ۱۵) and ۲۰% from the non-malignant control group (۷ of ۳۵). There was no herpes simplex DNA in the polyp tissues (۰ of ۲۰). Epstein-Barr DNA was found in ۶۰% of tumor samples (۹ of ۱۵), ۳۵% of polyp samples (۷ of ۲۰), and ۴۰% of the non-malignant control group (۱۴ of ۳۵). Statistical analysis showed no significant association between the prevalence of herpes simplex and Epstein- Barr viruses and the incidence of colorectal cancer and polyps compared with the control group.Conclusion: The results demonstrate a lack of direct molecular evidence to support an association between herpes simplex and Epstein-Barr viruses with human colorectal malignancies. These results do not exclude a possible oncogenic role of these viruses to infect different colon cells.