Box plots showing the distribution of CpG methylation levels per sample after aligning to HPV16 (S6a) and HPV16-L1 region (S6b). The CpG methylation median in the clinical samples is significantly higher than in the cell lines and higher in urine ccfDNA from the CIN3 than from the CIN1 clinical sample (p<0.05), as expected.
ARTICLE ABSTRACT
Clinically useful molecular tools to triage women for a biopsy upon referral to colposcopy are not available. We aimed to develop a molecular panel to detect cervical intraepithelial neoplasia (CIN) grade 2 or higher lesions (CIN2+) in women with abnormal cervical cytology and high-risk HPV (HPV+). We tested a biomarker panel in cervical epithelium DNA obtained from 211 women evaluated in a cervical cancer clinic in Chile from 2006 to 2008. Results were verified in a prospective cohort of 107 women evaluated in a high-risk clinic in Puerto Rico from 2013 to 2015. Promoter methylation of ZNF516, FKBP6, and INTS1 discriminated cervical brush samples with CIN2+ lesions from samples with no intraepithelial lesions or malignancy (NILM) with 90% sensitivity, 88.9% specificity, 0.94 area under the curve (AUC), 93.1% positive predictive value (PPV), and 84.2% negative predictive value (NPV). The panel results were verified in liquid-based cervical cytology samples from an independent cohort with 90.9% sensitivity, 60.9% specificity, 0.90 AUC, 52.6% PPV, and 93.3% NPV, after adding HPV16-L1 methylation to the panel. Next-generation sequencing results in HPV+ cultured cells, and urine circulating cell-free DNA (ccfDNA) were used to design assays that show clinical feasibility in a subset (n = 40) of paired plasma (AUC = 0.81) and urine (AUC = 0.86) ccfDNA samples obtained from the prospective cohort. Viral and host DNA methylation panels can be tested in liquid cytology and urine ccfDNA from women referred to colposcopy, to triage CIN2+ lesions for biopsy and inform personalized screening algorithms. Cancer Prev Res; 9(12); 915–24. ©2016 AACR.
