Alexandra Bukowski

Epigenome-wide differential methylation and differential variability as predictors of high-grade cervical intraepithelial neoplasia (CIN2+)

Abstract CpG site methylation patterns have potential to improve differentiation of high-grade screening-detected cervical abnormalities. We assessed CpG differential methylation (DM) and differential variability (DV) in high-grade (CIN2+) vs low-grade (≤ CIN1) lesions. In ≤ CIN1 (n = 117) and CIN2+ (n = 31) samples, cervical sample DNA underwent testing with Illumina HumanMethylation arrays. We assessed DM and DV of CpG methylation M-values among 9 cervical cancer–associated genes. We fit CpG-specific linear models and estimated empirical Bayes standard errors and false discovery rates (FDRs). An exploratory epigenome-wide association study (EWAS) aimed to detect novel DM and DV CpGs (FDR < 0.05) and Gene Ontology (GO) term enrichment. Compared to ≤ CIN1, CIN2+ exhibited greater methylation at CCNA1 cluster 1 (M-value difference 0.24; 95% CI, 0.04-0.43) and RARB cluster 2 (0.16; 95% CI, 0.05-0.28), and lower methylation at CDH1 cluster 1 (–0.15; 95% CI, –0.26 to –0.04). CIN2+ exhibited lower variability at CDH1 cluster 2 (variation difference –0.24; 95% CI, –0.41 to –0.05) and FHIT cluster 1 (–0.30; 95% CI, –0.50 to –0.09). EWAS detected 3534 DM and 270 DV CpGs. Forty-four GO terms were enriched with DM CpGs related to transcriptional, structural, developmental, and neuronal processes. Methylation patterns may help triage screening-detected cervical abnormalities and inform US screening algorithms. This article is part of a Special Collection on Gynecological Cancer.

Extended Human Papillomavirus Genotyping to Predict Progression to High-Grade Cervical Precancer: A Prospective Cohort Study in the Southeastern United States

Abstract Background: High-risk human papillomavirus (hrHPV) testing is utilized in primary cervical cancer screening, generally along with cytology, to triage abnormalities to colposcopy. Most screening-based hrHPV testing involves pooled detection of any hrHPV or of HPV16/18. Cervical neoplasia progression risks based on extended hrHPV genotyping—particularly non-16/18 hrHPV types—are not well characterized. HPV genotype-specific incidence of high-grade cervical intraepithelial neoplasia or more severe (CIN2+) following an abnormal screening result was examined. Methods: We assessed a US-based prospective, multiracial, clinical cohort of 343 colposcopy patients with normal histology (n = 226) or CIN1 (n = 117). Baseline cervical samples underwent HPV DNA genotyping, and participants were followed up to 5 years. Genotype-specific CIN2+ incidence rates (IR) were estimated with accelerated failure time models. Five-year CIN2+ risks were estimated nonparametrically for hierarchical hrHPV risk groups (HPV16; else HPV18/45; else HPV31/33/35/52/58; else HPV39/51/56/59/68). Results: At enrollment, median participant age was 30.1 years; most (63%) were hrHPV-positive. Over follow-up, 24 participants progressed to CIN2+ (7.0%). CIN2+ IR among hrHPV-positive participants was 3.4/1,000 person-months. CIN2+ IRs were highest for HPV16 (8.3), HPV33 (7.8), and HPV58 (4.9). Five-year CIN2+ risk was higher for HPV16 (0.34) compared with HPV18/45 (0.12), HPV31/33/35/52/58 (0.12), and HPV39/51/56/59/68 (0.16) (P = 0.05). Conclusions: Non-16/18 hrHPV types are associated with differential CIN2+ progression rates. HPV16, 33, and 58 exhibited the highest rates over 5 years. HPV risk groups warrant further investigation in diverse US populations. Impact: These novel data assessing extended HPV genotyping in a diverse clinical cohort can inform future directions to improve screening practices in the general population.