Human Papillomavirus Type 16 Integration Analysis by Real-time PCR Assay in Associated Cancers

摘要

Human papillomavirus(HPV)is a common viral infection worldwide associated with a variety of cancers. The integration of theHPVgenome in these patients causes chromosomal instability and triggers carcinogenesis. The aim of this study was to investigate theHPV-16genome physical status in four major cancers related toHPVinfection. Formalin-fixed paraffin-embedded blocks from our previous projects on head and neck, colorectal, penile, and cervical cancers were collected, andHPV-16–positive specimens were used for further analysis. The DNA extraction copy number ofE2andE7genes was calculated by qualitative real-time PCR method. Serially diluted standards that were cloned inPUC57plasmid were used. Standard curve and melting curve analysis was used for quantification. Of the 672 specimens studied, 76 (11.3%) wereHPV-16positive. We found that 35.6% (16/45) were integrated. Statistical analysis showed that there were significant correlations between integration ofHPV-16and cervical cancer end-stage carcinogenesis (P< .0001), episomal form, and ASCUS lesions (P= .045). Significant correlation in penile cancer patients was seen between the episomal form and high-grade cancer stage (P= .037). Integration is a major factor in the carcinogenesis mechanism ofHPVand has different prevalence in various cancers with a higher rate in progression except in penile cancer.