Viruses, Other Pathogenic Microorganisms and Esophageal Cancer

Abstract

Background: Esophageal cancer (EC) is the eighth most prevalent malignant tumor and the sixth leading cause of cancer mortality throughout the world. Despite the technical developments in diagnosis and treatment, the 5-year survival rate is still low. The etiology of EC remains poorly understood; multiple risk factors may be involved and account for the great variation in EC incidence in different geographic regions. Summary: Infection with carcinogenetic pathogens has been proposed as a risk factor for EC. This review explores the recent studies on the association of human papillomavirus (HPV), Epstein-Barr virus (EBV), Helicobacter pylori and esophageal bacterial biota with EC. Key Message: Among the above-mentioned pathogens, HPV most likely contributes to esophageal squamous cell carcinoma (ESCC) in high-risk populations. New techniques are being applied to studies on the role of infection in EC, which will inevitably bring novel ideas to the field in the near future. Practical Implications: Multiple meta-analyses support the finding of a higher HPV detection rate in regions associated with high risk for ESCC compared to low-risk areas. A potential role of HPV in the rise of esophageal adenocarcinoma (EAC) was proposed recently. However, further studies are required before a firm conclusion can be drawn. Less work has been done in studying the association between EBV and ESCC, and the results are quite controversial. H. pylori infection is found to be inversely related to EC, which is probably due to the reduced incidence of gastroesophageal reflux disease. Analysis of the esophageal bacterial biota revealed distinct clusters of bacteria in normal and diseased esophagi. A type II microbiome rich in Gram-negative bacteria potentially contributes to EAC by inducing chronic inflammation. Novel findings from such studies as these may benefit public health by justifying anti-infection measures to prevent EC.

Prevalence of high Risk Human Papilloma Viruses 16 and 18 (HR-HPV16&18) Among Sudanese Patients with Esophageal Cancer

“…A potential role of HPV in the rise of esophageal AC was proposed recently. Multiple metaanalyses support the outcome of a higher HPV detection rate in regions associated with high risk for esophageal SCC compared to low-risk areas [9]. A meta-analysis showed that HPV16 and 18 can be detected in esophageal SCC.…”

Green Tea and Its Extracts in Cancer Prevention and Treatment

“…Among esophageal cancers, location (proximal and distal carcinoma) and histological subtype (adenocarcinoma and squamous cell carcinoma) can be separated [215][216][217][218][219], with differing etiology and prognosis. The upper gastrointestinal tract is most likely to show a specific response; this has been proven for viruses like human papilloma viruses [220] or hot and spicy food [221][222][223], cooking with wood and coal also are likely etiological agents [224,225]. In addition, genetic factors [226,227] contribute to the individual cancer risk, antibiotic treatment of H. pylori gastritis has caused a shift from squamous cell carcinoma to adenocarcinoma in esophageal cancers [218].…”

Host-Microbiome Interaction and Cancer: Potential Application in Precision Medicine

“…Multiple meta-analyses support the discovery of a higher HPV detection rate in regions associated with high risk for esophageal squamous cell carcinoma (ESCC), compared to low-risk areas. Additionally, a potential role of HPV in the rise of esophageal adenocarcinoma (EAC) was proposed recently; however, future studies are required (Xu et al, 2015). …”