Methylation of human papillomavirus-52 and -58 is a candidate biomarker in cervical neoplasia

Background: Previous studies of human papillomavirus (HPV)16/18 genome methylation have concluded that methylation status of the L1 gene might act as a biomarker for cervical intraepithelial neoplasia (CIN).

Objectives: We investigated the correlation between methylation status in the L1 gene and the long control region (LCR) of HPV52/58 and CIN.

Study design: Exfoliated cervical cells were taken from 54 HPV52-positive and 41 HPV58-positive women. The HPV genome was examined using bisulfite modification, polymerase chain reaction amplification, and sequencing.

Results: The CpGs were unmethylated or hypomethylated in the HPV52/58 LCR. In contrast, the methylation status of the HPV52 L1 gene was correlated with the severity of cervical neoplasia, with average percentages of 15%, 34%, and 52% for cervicitis/CIN1, CIN2, and CIN3, respectively (P<0.05). Methylation status of the HPV52 L1 gene was also correlated with the prognosis of CIN1/2, with median percentages of 15% and 35% for regression and persistence/progression, respectively (P<0.05). The methylation status of the HPV58 L1 gene was correlated with the severity of cervical neoplasia, with average percentages of 12%, 38%, and 61% for cervicitis/CIN1, CIN2, and CIN3, respectively (P<0.05).

Conclusions: The increased methylation at the CpG sites in the HPV52/58 L1 gene was correlated with the severity of cervical neoplasia, similar to HPV16/18 in previous studies. These data suggest that HPV methylation status of the L1 gene is a candidate biomarker of CIN for detecting CIN2 and CIN3.