Elevated expression of human papillomavirus-16/18 E6 oncoprotein associates with persistence of viral infection: A 3-year prospective study in China

Background: An association between high-risk human papillomavirus (HR-HPV) oncoprotein expression and viral persistence has been suggested by the outcome of etiology studies, but there are no epidemiologic studies evaluating that link. Methods: We performed a 3-year prospective study in which 2,498 Chinese women ages 25 to 65 years were screened by six screening tests, including the OncoE6 Cervical Test (Arbor Vita Corporation) in 2011 (baseline). Six-hundred and ninety women who were positive for any of the tests and a random sample of 164 women with all negative results received colposcopy, and cervical specimens for the cobas 4800 HPV test ("cobas," Roche Molecular Systems) were collected before colposcopy; of this group, 737 cervical specimens were collected to perform cobas and OncoE6 Cervical Test in 2014 (follow-up). Twenty-four cases of HPV16/18 E6 positives and 204 selected controls at baseline, 13 cases of HPV16/18 E6 positive and another 204 selected controls at follow- up were analyzed separately using unconditional logistical regressionmodels to estimate ORs and 95% confidence intervals (CI). Results: Compared with women who were HPV16 E6 oncoprotein negative at baseline, women in the E6-positive group had a much higher risk of HPV persistence (adjusted OR, 54.64; 95% CI, 7.19-415.09) at 3-year follow-up; a statistically strong association was also found between HPV16/18 HPV persistence and E6 oncoprotein expression detected at follow-up (adjusted OR, 360.57; 95% CI, 28.30-4,593.55). Conclusions: A single detection of HPV16/18 E6 oncoprotein expression was strongly associated with viral persistence. Impact: HPV16/18 E6 oncoprotein constitutes a marker for risk of HPV persistence.