Detection of human papillomavirus in Chinese esophageal squamous cell carcinoma and its adjacent normal epithelium.

Aim: To investigate the putative role of human papillomavirus (HPV) infection in the carcinogenesis of esophageal squamous cell carcinoma in China.

Methods: Twenty-three esophageal squamous cell carcinoma samples and the distal normal epithelium from Shanxi Province, and 25 more esophageal squamous cell carcinoma samples from Anyang city, two areas with a high incidence of esophageal cancer in China, were detected for the existence of HPV-16 DNA by PCR, mRNA in situ hybridization (ISH) and immunohistochemistry (IHC) targeting HPV-16 E6 gene.

Results: There were approximately 64 % (31/48) patients having HPV-16 DNA in tumor samples, among them nearly two-thirds (19/31) samples were detected with mRNA expression of HPV-16 E6. However, in the normal esophageal epithelium from cancer patients, the DNA and mRNA of HPV-16 were found with much less rate: 34.7 % (8/23) and 26.1 % (6/23) respectively. In addition, at protein level detected by IHC assay, 27.1 % (13/48) tumor samples had virus oncoprotein E6 expression, while only one case of normal epithelium was found positive.

Conclusion: HPV infection, especially type 16, should be considered as a risk factor for esophageal malignancies in China.