Evidence of HPV16 integration in low- and high-grade cervical lesions that regress demonstrated by multiple displacement amplification and southern blot hybridization

Abstract

The prevalence and significance of HPV integration among different grades of cervical lesions is uncertain. In this study, HPV physical status has been examined by the combination of multiple displacement amplification (MDA) with southern blot hybridization (SBH). DNA extracts from ninety-five cervical cytological samples (ASC-US, LSIL, ASC-H, HSIL, NILM) were subject to whole genome amplification by MDA followed by SBH with α-32P labeled HPV probes. Mixed HPV16 episomal/integrant sequences were detected in: three ASC-US patients, two diagnosed with benign changes and one with CIN2/3 after biopsy follow-up; one ASC-H patient with CIN2/3 histological diagnosis; and, one HSIL patient with benign changes. Additional follow-up cytological data available for three of these patients demonstrated series of lesion-free samples. The data support the view that integration can occur in low-grade lesions and that lesions with mixed episomal/integrant HPV can regress.