Human papillomavirus is an important risk factor for esophageal carcinoma in a Chinese population

Purpose: Different types of HPV have been associated with cancer in humans, but the role of HPV in esophageal cancer (EC) is controversial. The purpose of this study was to evaluate the correlation between HPV infection and EC in the Chinese population and to provide the scientific basis for the future prevention, control, early diagnosis, and treatment strategies of EC in China.

Methods: PCR detected HPV infection in 1112 esophageal cancer tissue samples, and 89 HPV-positive samples were detected by genotyping. Proximity ligation assays (PLAs) and immunohistochemistry were used to detect the expression of HPV E6 and E7 proteins. Real-time fluorescent quantitative PCR was used to detect the integration of HPV16 E6. The level of HPV-specific antibody IgG in serum was detected by ELISA and PLA.

Results: The positive rates of HPV L1, HPV16, HPV18, hpv16 + 18 E6 and hpv16/18 E6 in 1,112 EC tissue samples were 77.6%, 41.4%, 27.2%, 14.2% and 55.4% respectively. Multiple HPV subtypes were detected in HPV-positive EC samples. PLA showed that E6 and E7 were expressed in EC109 and formed complexes with p53 and pRb, respectively. Immunohistochemistry showed that the positive rates of hpv16 + 18 E6 and E7 in HPV-positive EC samples were 56.4% and 37.0%, respectively. HPV-DNA integration rate in HPV-positive EC tissues (88.79%) was higher than that in adjacent tissues (54.17%). HPV antibody was found in the serum of EC patients by a serological test.

Conclusion: The study suggests that HPV, especially HPV16 and HPV18, the infection may be a risk factor for EC in the Chinese population and that the E6 protein may play a key role in HPV-associated malignancies. These results may be important for the prevention and treatment of HPV-positive EC in China.