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 15 patients with colorectal cancer, 20 patients with colorectal polyps and 35 patients without malignancy as controls. Biopsy specimens were frozen under sterile conditions at -20?C. 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 ?2 test. Results: We observed herpes simplex DNA in 33.3% of tumor samples (5 of 15) and 20% from the non-malignant control group (7 of 35). There was no herpes simplex DNA in the polyp tissues (0 of 20). Epstein-Barr DNA was found in 60% of tumor samples (9 of 15), 35% of polyp samples (7 of 20), and 40% of the non-malignant control group (14 of 35). 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.