Specifically, the HPV genome in the form of extrachromosomal plasmids may tether randomly or pairwise to sister chromatids at the viral origin of replication (ori) by HPV E2 binding. During cell division, two models of viral genome replication have been described, i.e., Random Attachment and Faithful Partitioning. “Accidental integration” may result from intimate interactions between the viral and host genomes throughout replication. Throughout the viral life cycle, HPV replicates in three distinct phases, namely, “initial replication” after viral entry, “maintenance replication” during cellular replication, and “vegetative replication” in differentiated cells. The HPV genome is an ~8000 base pair (bp), double-stranded, circular DNA encoding 6 early genes ( E1, E2, E4, E5, E6, and E7) and 2 late genes ( L1 and L2). Applying HPV VIS-mapping to pre- or invasive tumors will advance our understanding of viral oncogenesis and facilitate the discovery of prognostic biomarkers and therapeutic targets. Overall, the VHC and VIS workflows proved to be a rapid and accurate means of localizing viral-host integration site(s) and identifying disrupted and neighboring human genes. Key findings, including disrupted and nearby genes, were summarized in an auto-generated report. The VIS dynamic graphical outputs included read mappings, virus-host genomic breakpoints, and virus-host integration circular plots. The VHC and VIS workflow median runtimes were 19 and 7 min per sample, respectively. The workflows embedded with HPV and human reference genomes were used to analyze a publicly available NGS dataset derived from pre- and cancerous HPV+ cervical cytology of 21 Gabonese women.
Here, we tested two new, automated workflows in CLC Microbial Genomics, i.e., Viral Hybrid Capture (VHC) Data Analysis and Viral Integration Site (VIS) Identification for software performance and efficiency. However, a simple, streamlined bioinformatics workflow has been non-existent until recently. With next-generation sequencing (NGS), identification of viral and host genomic breakpoints and chimeric sequences are now possible. Human papillomavirus (HPV) integration within the host genome may contribute to carcinogenesis through various disruptive mechanisms.