Targeted next generation sequencing panel for HPV genotyping in cervical cancer

Abstract

Cervical cancer are generally caused by a persistent infection with the oncogenic virus, HPV. Patients with HPV integration are more prone to develop cervical cancer than patients without integration. In this proof-of-concept study, we aimed to develop a sensitive method based on targeted amplicon based NGS for early and precise detection of high-risk HPV-genotypes that are highly associated with the development of cervical cancer. Furthermore, we aimed to investigate if amplicon based NGS allowed for HPV genotyping in cervical lesions and whether it could detect HPV integration. The cohort included a group of CIN3⁺ biopsies (n = 64), CIN2 samples that progressed (n = 5), CIN2 samples that regressed (n = 3), healthy controls (n = 10), and plasma samples (n = 10) from cervical cancer patients. Sequencing was performed using a custom targeted NGS panel designed to detect all 25 high-risk and probably high-risk and two low-risk HPV genotypes. The method was validated by the SPF₁₀ PCR-DEIA-LiPA₂₅ assay. In the cohort, the following HPV genotypes were identified: HPV-16, 18, 31, 33, 35, 45, 51, 52, 56, 58, and 59. When comparing the results from the SPF₁₀ PCR-DEIA-LiPA₂₅ analyses with the NGS analyses, there was close to a perfect agreement (K = 0.92) among the genotyped HPV types, while in the two cases with complete disagreement, a third assay was applied, and here the results of the NGS analyses were confirmed. Whereas multiple HPV types were detected by the SPF₁₀ PCR-DEIA-LiPA₂₅ assay, the NGS analysis clearly suggest that there is one predomentant HPV type. The NGS assay was capable of detecting HPV-16 in a previous false-negative sample classified by the INNO-LiPA assay, emphasizing the importance of including multiple regions of the HPV genome when genotyping. For the 10 plasma samples, our NGS analyses showed full agreement with the digital droplet PCR (ddPCR) analyses of HPV positive as well as negative plasma samples. Lastly, the custom panel was capable of detecting the integration of HPV-16 in the SiHa cell line. The HPV panel provides a highly cost-effective method for HPV detection and genotyping, as exemplified by a list price of around 75 € per sample. In conclusion, the current study demonstrates that targeted NGS is capable of detecting and genotyping HPV in both FFPE biopsies and plasma samples. This method provides for early diagnosis and prognosis of cervical cancer disease progression, thereby optimizing the potential of recovery and survival for these patients.

Keywords: Cervical cancer; Cervical intraepithelial neoplasia grade 2; HPV genotyping; Human papillomavirus; Next generation sequencing.