Howard D. Strickler

Epidemiological evidence that common HPV types may be common because of their ability to evade immune surveillance: Results from the Women's Interagency HIV study

Infection by human papillomavirus (HPV) type 16, the most oncogenic HPV type, was found to be the least affected by HIV‐status and CD4 count of any of the approximately 13 oncogenic HPV types. This relative independence from host immune status has been interpreted as evidence that HPV16 may have an innate ability to avoid the effects of immunosurveillance. However, the impact of immune status on other individual HPV types has not been carefully assessed. We studied type‐specific HPV infection in a cohort of 2,470 HIV‐positive (HIV[+]) and 895 HIV‐negative (HIV[−]) women. Semi‐annually collected cervicovaginal lavages were tested for >40 HPV types. HPV type‐specific prevalence ratios (PRs), incidence and clearance hazard ratios (HRs), were calculated by contrasting HPV types detected in HIV[+] women with CD4 < 200 to HIV[−] women. HPV71 and HPV16 prevalence had the weakest associations with HIV‐status/CD4 count of any HPV, according to PRs. No correlations between PRs and HPV phylogeny or oncogenicity were observed. Instead, higher HPV type‐specific prevalence in HIV[−] women correlated with lower PRs (ρ = −0.59; p = 0.0001). An alternative (quadratic model) statistical approach (PHIV+ = a*PHIV− + b*PHIV−2; R2 = 0.894) found similar associations (p = 0.0005). In summary, the most prevalent HPV types in HIV[−] women were the types most independent from host immune status. These results suggest that common HPV types in HIV[−] women may have a greater ability to avoid immune surveillance than other types, which may help explain why they are common.

A novel human papillomavirus and host DNA methylation score and detection of cervical adenocarcinoma

Abstract Background The widespread introduction of Pap testing in the 1960s was followed by substantial reductions in the incidence of cervical squamous cell cancer (SCC). However, the incidence of cervical adenocarcinoma (ADC) did not decrease, likely because of low Pap test sensitivity for ADC and adenocarcinoma in situ (AIS). This study assessed a novel human papillomavirus (HPV) and host DNA Methylation Score for AIS and ADC screening. Methods We measured methylation levels at CpG sites in the L2/L1 open reading frames of HPV16, HPV18, and HPV45—as well as 2 human loci, DCC and HS3ST2. Specifically, we tested exfoliated cervicovaginal cells from women in the HPV Persistence and Progression (PaP) cohort who were positive for 1 of HPV16, 18, or 45, including: 1) 176 with AIS/ADC, 2) 353 with cervical intraepithelial neoplasia–3 (CIN3) or SCC, and 3) controls who either cleared (HPV-Clearers; n = 579) or had persistent HPV16, 18, or 45 infection (HPV-Persisters; n = 292). CpG site–specific methylation percentages were measured using our reported next-generation methods. The Methylation Score was the average methylation percentage across all 35 CpG sites tested. Results Each individual CpG site had higher methylation percentages in exfoliated cervicovaginal cells collected from patients with AIS/ADC, and as well as those with CIN3/SCC, relative to either control group (weakest P  = .004). The Methylation Score for AIS/ADC had a sensitivity of 74% and specificity of 89%. The multivariate odds ratio (OR) between the Methylation Score (4th vs 1st quartile) for AIS/ADC was ORq4-q1 = 49.01 (PBenjamini-Hochberg = 4.64E-12), using HPV-Clearers as controls. CIN3/SCC had similar, albeit weaker, associations with the Methylation Score. Conclusions HPV16/18/45-infected women with Methylation Scores in the highest quartile had very high odds of AIS/ADC, suggesting they may warrant careful histologic evaluation of the cervical transition zone (eg, conization or loop electrosurgical excision procedure [LEEP]).