Effectiveness of HPV 16 viral load and the E2/E6 ratio for the prediction of cervical cancer risk among Chinese women.

The effectiveness of the E2/E6 ratio, the state of viral genome integration and the viral load of human papillomavirus 16 (HPV 16) in predicting the risk of cervical cancer among Chinese women was investigated. Quantitative PCRs for the E2/E6 ratio and the viral load were performed on 85 cervical cancer samples and 55 HPV 16 positive healthy controls. The integrated form of the viral genome was found in 10.9% control samples and in 26.4% cervical cancer samples (P = 0.02). The majority of the cervical cancer (63.2%) and control samples (60%) were mixed forms. The E2/E6 ratio was associated with a high risk of cervical cancer (OR = 7.29, P = 9.55E-6). The integrated form (OR = 6.54, P = 0.005) and mixed form (OR = 2.93, P = 0.042) increased the risk of cervical cancer. The mean viral load in cervical cancer samples (37,371 ± 227,135) was higher than that in the controls (4,619 ± 27,079; P = 0.011). Additionally, the viral load increased along with the cervical cancer progression from the International Federation of Gynecology and Obstetrics (FIGO) stage I (12,337 ± 25,604) to stage II (67,453 ± 319,821). Compared with the state of viral genome integration (area under the receiver operating characteristic curve (AUC) = 0.743) or the viral load (AUC = 0.694), the E2/E6 ratio improved the effectiveness of the risk prediction of cervical cancer (AUC = 0.777), with the sensitivity (specificity) 81.2% (71.7%). The state of viral genome integration and the viral load of HPV 16 were important factors for the risk prediction of cervical cancer among Chinese women, and the E2/E6 ratio had a better cervical cancer risk prediction with age adjustment.