Follow-up of high-risk HPV positive women by combined cytology and bi-marker CADM1/MAL methylation analysis on cervical scrapes

OBJECTIVES

Triage of HPV screen-positive women is needed to identify those with underlying cervical intraepithelial neoplasia grade 2/3 or worse (CIN2/3+). Presently, cytology on a physician-taken cervical scrape is mostly accepted as triage test, but needs follow-up testing in order not to miss severe disease. Here, we evaluated the performance of combined cytology and bi-marker CADM1/MAL-methylation analysis as triage test on physician-taken cervical scrapes of HPV positive women.

METHODS

In this post-hoc analysis, we used 364 left-over HPV positive cytology triage samples of participants of a randomized controlled trial (PROHTECT-3: n=46,001) performed in population-based cervical screening. Study endpoints were CIN2+ and CIN3+ detection. Cytology testing with and without methylation marker analysis was evaluated with regard to sensitivity, specificity, positive and negative predictive value, and referral rate.

RESULTS

Bi-marker CADM1/MAL-methylation positivity increased proportionally with severity of underlying lesions. Overall, cytology and bi-marker CADM1/MAL-methylation analysis yielded similar performances with regard to CIN3+ detection, yet in combination a significantly higher sensitivity for CIN3+ (88.7%) was obtained at a specificity of 53.6% and a colposcopy referral rate of 53.6%. The combined strategy detected all six cervical cancers, whereas triage by cytology alone failed to detect two of them.

CONCLUSIONS

Cytology and bi-marker CADM1/MAL-methylation analysis perform complementary for CIN2+/CIN3+ detection when used as triage tool on cervical scrapes of HPV positive women. This approach not only results in a higher CIN3+ sensitivity than cytology triage with an acceptable referral rate, but also seems to reduce the risk of missing cervical cancers and advanced high-grade lesions.

Longitudinal assessment of DNA methylation changes during HPVE6E7-induced immortalization of primary keratinocytes

High-risk human papillomavirus (hrHPV)-induced immortalization and malignant transformation are accompanied by DNA methylation of host genes. To determine when methylation is established during cell immortalization and whether it is hrHPV-type dependent, DNA methylation was studied in a large panel of HPVE6E7-immortalized keratinocyte cell lines. These cell lines displayed different growth behaviors, i.e., continuous growth versus crisis period prior to immortalization, reflecting differential immortalization capacities of the 7 HPV-types (16/18/31/33/45/66/70) studied. In this study, cells were monitored for hypermethylation of 14 host genes (APC, CADM1, CYGB, FAM19A4, hTERT, mir124-1, mir124-2, mir124-3, MAL, PHACTR3, PRDM14, RASSF1A, ROBO3, and SFRP2) at 4 different stages during immortalization. A significant increase in overall methylation levels was seen with progression through each stage of immortalization. At stage 1 (pre-immortalization), a significant increase in methylation of hTERT, mir124-2, and PRDM14 was already apparent, which continued over time. Methylation of ROBO3 was significantly increased at stage 2 (early immortal), followed by CYGB (stage 3) and FAM19A4, MAL, PHACTR3, and SFRP2 (stage 4). Methylation patterns were mostly growth behavior independent. Yet, hTERT methylation levels were significantly increased in cells that just escaped from crisis. Bisulfite sequencing of hTERT confirmed increased methylation in immortal cells compared to controls, with the transcription core and known repressor sites remaining largely unmethylated. In conclusion, HPV-induced immortalization is associated with a sequential and progressive increase in promoter methylation of a subset of genes, which is mostly independent of the viral immortalization capacity.

Twelve-month incidence and clearance of oral HPV infection in HIV-negative and HIV-infected men who have sex with men: the H2M cohort study

BACKGROUND

Our aim was to compare the 12-month incidence and clearance of oral high-risk HPV infection between HIV-infected men who have sex with men (MSM) and HIV-negative MSM.

METHODS

MSM aged 18 years or older were recruited in Amsterdam, the Netherlands. Questionnaire data and oral-rinse and gargle samples were collected at baseline, and after 6 and 12 months. HPV DNA was genotyped using the SPF10-PCR & DEIA-LiPA25 system (version 1). Determinants of oral HPV incidence and clearance were explored using Cox and logistic regression analyses respectively.

RESULTS

433 HIV-negative and 290 HIV-infected MSM were included in these analyses. The median follow-up time per participant was 12 months (range 3-15). During follow-up, 114 incident oral high-risk HPV infections were observed. The incidence rate of HPV-16 was 3.5/1000 person-months (PM) in HIV-infected and 0.9/1000 PM in HIV-negative MSM (IRR 4.1; 95% CI 1.3-13.2). The incidence rates of other high-risk HPV types ranged between 1.3-3.5/1000 PM in HIV-infected and 0.0-1.1/1000 PM in HIV-negative MSM. In multivariable analyses, HIV infection (adjusted hazard ratio [aHR] 3.8; 95% CI 2.3-6.2) and a higher number of recent oral sex partners (aHR 2.4 for ≥8 partners compared to ≤2; 95% CI 1.4-4.2) were associated with HPV incidence. Of the 111 baseline oral high-risk infections, 59 (53.2%) were cleared. In multivariable analyses, only a higher number of recent oral sex partners was associated with HPV clearance (adjusted odds ratio 3.4 for ≥8 compared to ≤2 partners; 95% CI 1.3-9.0).

CONCLUSIONS

The incidence rate of oral high-risk HPV infection was higher in HIV-infected MSM and in those with a higher number of recent oral sex partners. Just over half of the oral high-risk HPV infections at baseline were cleared after 12 months, with a higher likelihood of clearance among MSM reporting higher numbers of recent oral sex partners, but no difference by HIV status.

Women's Preferences of Dynamic Spectral Imaging Colposcopy

BACKGROUND

The focus of testing the dynamic spectral imaging (DSI) colposcope has been on the technical characteristics and clinical performance. However, aspects from a patient's perspective are just as important.

METHODS

This study was designed as a substudy of the DSI validation study, a prospective comparative, multicenter clinical trial to assess the clinical performance of DSI colposcopy. All women included in this study were asked to complete two questionnaires: a patient characteristics questionnaire and a patient satisfaction questionnaire.

RESULTS

In the initial study a total of 239 women were included in the intention-to-treat cohort. Of these, 230 women (96.2%) completed both questionnaires. When assessing the women's preferences for some of the possible uses of DSI colposcopy, a high level of agreement was noted for all potential implementations. In general, women found the additional time DSI colposcopy took acceptable: just 15 women (6.5%) thought the time DSI colposcopy took made them feel uncomfortable. Furthermore, women ranked test accuracy as the most important characteristic, followed by (more) rapid testing and comfort. Quick notification of the results and costs were considered the least important characteristics.

CONCLUSION

Women are willing to accept discomfort in the form of an additional or longer test if there is clinical benefit.

The age distribution of type-specific high-risk human papillomavirus incidence in two population-based screening trials

BACKGROUND

Age- and type-specific high-risk human papillomavirus (hrHPV) incidence estimates in screen-eligible women are relevant from a public health perspective because they provide an indication of the effect of vaccination on the occurrence of screen-positives in HPV-based screening. However, limited data from women over 25 years of age are available.

METHODS

In 24,105 hrHPV-negative women participating in Dutch (Population-Based Screening Study Amsterdam: POBASCAM) and Italian (New Technologies for Cervical Cancer: NTCC) population-based randomized controlled screening trials the age- and type-specific distribution of incident hrHPV infections detected at the next screening round was assessed. HPV types were grouped into vaccine (bivalent: HPV16/18; polyvalent HPV16/18/31/33/45/52/58) and nonvaccine types.

RESULTS

The incidence of screen-detected hrHPV among women ages 29 to 56 years was 2.54% (95% confidence interval, 2.30-2.78) in POBASCAM and 2.77% (2.36-3.19) in NTCC. In both studies, the incidence of bivalent, polyvalent, and nonpolyvalent infections decreased with age (P < 0.0001). Among women with incident infection(s), vaccine-type positivity changed quadratically with age, in particular for the polyvalent vaccine (P values: POBASCAM: bivalent 0.264, polyvalent 0.038; NTCC bivalent 0.039, polyvalent 0.005). However, more than 20% and 50% of women with incident hrHPV were positive for bivalent and polyvalent vaccine types, respectively, in all ages in both studies.

CONCLUSIONS

We observed decreasing age trends of hrHPV vaccine and nonvaccine type incidences and age-related differences in the vaccine-type positivity among women with incident infections. Most importantly, hrHPV infections continued to be detected in all ages and the contribution of vaccine types remained substantial.

IMPACT

Our results indicate a considerable reduction of new hrHPV infections in vaccinated cohorts, ensuing revision of screening guidelines.

Methylation analysis of the FAM19A4 gene in cervical scrapes is highly efficient in detecting cervical carcinomas and advanced CIN2/3 lesions

Primary testing for human papillomavirus (HPV) in cervical screening requires triage to differentiate women with transient infection from those with persistent infection who require more intensive management given their risk for cervical (pre)cancer. In this study, the clinical performance of a novel methylation marker FAM19A4 for the triage of high-risk (hr)HPV-positive women was evaluated. Using a training-validation set approach, we analyzed a FAM19A4 quantitative methylation-specific PCR (qMSP). The training set comprised hrHPV-positive cervical scrapes of 43 women with cervical intraepithelial neoplasia grade 3 or worse (CIN3+) and 135 women with ≤CIN1. The validation set comprised hrHPV-positive cervical scrapes of 52 women with CIN2+, including 33 CIN3+, 19 CIN2, and 166 women with ≤CIN1. The methylation threshold of FAM19A4 qMSP that gave rise to CIN3+ specificity of 70% in the training set was applied in the validation set. This resulted in CIN3+ sensitivity of 75.8% [95% confidence interval (CI), 61.1-90.4] at 67.0% (95% CI, 60.3-73.8) specificity. Next, the validated qMSP was applied to an independent series of hrHPV-positive cervical scrapes of 22 women with cervical cancer, 29 with advanced CIN2/3 [i.e., women with a known preceding hrHPV infection (PHI) lasting ≥5 years as proxy of longer duration of lesion existence], and 19 with early CIN2/3 (i.e., PHI <5 years). All carcinomas (22/22) and advanced CIN2/3 lesions (29/29) were FAM19A4 methylation-positive, compared with 42.1% (8/19; 95% CI, 19.9-64.3) of early CIN2/3 lesions. In conclusion, FAM19A4 is an attractive triage marker for hrHPV-positive women, with a high reassurance for the detection of cervical carcinoma and advanced CIN2/3 lesions.

Acquisition and persistence of human papillomavirus 16 (HPV-16) and HPV-18 among men with high-HPV viral load infections in a circumcision trial in Kisumu, Kenya

BACKGROUND

Circumcision and lower human papillomavirus (HPV) viral loads in men are possibly associated with a reduced risk of HPV transmission to women. However, the association between male circumcision and HPV viral load remains unclear.

METHODS

Swab specimens from the glans and shaft of the penis were collected from men enrolled in a circumcision trial in Kisumu, Kenya. GP5+/6+ polymerase chain reaction (PCR) was used to identify HPV DNA types. HPV-16 and HPV-18 loads were measured with a LightCycler real-time PCR and classified as high (>250 copies/scrape) or low (≤250 copies/scrape).

RESULTS

A total of 1159 men were randomly assigned to undergo immediate circumcision, and 1140 men were randomly assigned to the control arm (these individuals were asked to remain uncircumcised until the study ended). The hazard of acquisition of high-viral load infections in the glans was lower in the circumcision arm, compared with the control arm, for HPV-16 (hazard ratio [HR], 0.32 [95% confidence interval {CI}, .20-.49]) and HPV-18 (HR, 0.34 [95% CI, .21-.54]). The 6-month risk of HPV persistence among men with high-viral load infections in the glans at baseline was lower in the circumcision arm, compared with the control arm, for HPV-16 (risk ratio [RR], 0.36 [95% CI, .18-.72]) and HPV-18 (RR 0.34 [95% CI, .13-.86]). Weaker and less precise results were obtained for shaft samples.

CONCLUSIONS

Male circumcision could potentially reduce the risk of HPV transmission to women by reducing the hazard of acquisition, and the risk of persistence of high-HPV viral load infections in the glans in men.

Methylation-mediated repression of PRDM14 contributes to apoptosis evasion in HPV-positive cancers

Promoter methylation of the transcription factor PRDM14 (PRDI-BF1 and RIZ domain containing 14) represents a highly frequent event in human papillomavirus (HPV)-induced cervical cancers and cancer precursor lesions. Here, we aimed to assess the functional consequences of PRDM14 promoter methylation in HPV-induced carcinogenesis. PRDM14 promoter methylation, expression and consequences of ectopic PRDM14 expression were studied in HPV16-positive cervical and oral cancer cell lines (SiHa, CaSki and 93VU147T), human embryonic kidney 293 (HEK293T) cells and primary human foreskin keratinocytes (HFK). PRDM14 mRNA expression was restricted to HEK293T and HFK cells, and could be upregulated in SiHa cells upon DNA methylation inhibition. Ectopic expression of PRDM14 in SiHa, CaSki and 93VU147T cells resulted in significantly more apoptotic cells, as measured by annexin V labelling, compared to HEK293T and HFK cells. MRNA profiling of 41 apoptosis regulators identified NOXA and PUMA as candidate target genes involved in PRDM14-mediated apoptosis induction. Full-length PRDM14 transactivated both NOXA and PUMA promoters. Transactivation was abolished upon deletion of the PRDM14 DNA binding domain. This suggests that NOXA and PUMA expression is directly regulated by PRDM14, which in case of NOXA was linked to a consensus PRDM14 binding motif in the promoter region. Taken together, these results suggest that PRDM14 acts as a regulator of NOXA and PUMA-mediated apoptosis induction, thereby providing evidence for a tumour suppressive role in HPV-induced carcinogenesis. The contribution of methylation-mediated gene silencing of PRDM14 to apoptosis evasion in HPV-positive cancer cells offers novel therapeutic options for HPV-induced cancers.

Methylation marker analysis and HPV16/18 genotyping in high-risk HPV positive self-sampled specimens to identify women with high grade CIN or cervical cancer

OBJECTIVES

Methylation marker analysis using bi-marker panel MAL/miR-124-2 is a promising triage test for identifying cervical (pre)cancer in high-risk human papillomavirus (hrHPV) positive women. Bi-marker panel MAL/miR-124-2 can be applied directly on self-sampled cervico-vaginal material and its sensitivity is non-inferior to that of cytology, yet at the cost of more colposcopy referrals. Our objective was to increase specificity of MAL/miR-124-2 methylation analysis by varying the assay thresholds and adding HPV16/18 genotyping.

METHODS

1019 hrHPV-positive women were selected from a randomized controlled self-sampling trial (PROHTECT-3; 33-63 years, n=46,001) and nine triage strategies with methylation testing of MAL/miR-124-2 and HPV16/18 genotyping were evaluated. The methylation assay threshold was set at four different predefined levels which correspond with clinical specificities for end-point cervical intra-epithelial grade 3 or worse (CIN3+) of 50%, 60%, 70%, and 80%.

RESULTS

The CIN3+ sensitivity of methylation analysis decreased (73.5 to 44.9%) while specificity increased (47.2 to 83.4%) when increasing the assay threshold. CIN3+ sensitivity and specificity of HPV16/18 genotyping were 68.0% and 65.6%, respectively. Combined methylation analysis at threshold-80 and HPV16/18 genotyping yielded similar CIN3+ sensitivity as that of methylation only at threshold-50 (77.6%) with an increased specificity (54.8%).

CONCLUSIONS

Combined triage by MAL/miR-124-2 methylation analysis with threshold-80 and HPV16/18 genotyping reaches high CIN3+ sensitivity with increased specificity to identify women with cervical (pre)cancer among HPV self-sample positive women. The combined strategy is attractive as it is fully molecular and identifies women at the highest risk of cervical (pre)cancer because of strongly elevated methylation levels and/or HPV16/18 positivity.

Comprehensive control of human papillomavirus infections and related diseases

Infection with human papillomavirus (HPV) is recognized as one of the major causes of infection-related cancer worldwide, as well as the causal factor in other diseases. Strong evidence for a causal etiology with HPV has been stated by the International Agency for Research on Cancer for cancers of the cervix uteri, penis, vulva, vagina, anus and oropharynx (including base of the tongue and tonsils). Of the estimated 12.7 million new cancers occurring in 2008 worldwide, 4.8% were attributable to HPV infection, with substantially higher incidence and mortality rates seen in developing versus developed countries. In recent years, we have gained tremendous knowledge about HPVs and their interactions with host cells, tissues and the immune system; have validated and implemented strategies for safe and efficacious prophylactic vaccination against HPV infections; have developed increasingly sensitive and specific molecular diagnostic tools for HPV detection for use in cervical cancer screening; and have substantially increased global awareness of HPV and its many associated diseases in women, men, and children. While these achievements exemplify the success of biomedical research in generating important public health interventions, they also generate new and daunting challenges: costs of HPV prevention and medical care, the implementation of what is technically possible, socio-political resistance to prevention opportunities, and the very wide ranges of national economic capabilities and health care systems. Gains and challenges faced in the quest for comprehensive control of HPV infection and HPV-related cancers and other disease are summarized in this review. The information presented may be viewed in terms of a reframed paradigm of prevention of cervical cancer and other HPV-related diseases that will include strategic combinations of at least four major components: 1) routine introduction of HPV vaccines to women in all countries, 2) extension and simplification of existing screening programs using HPV-based technology, 3) extension of adapted screening programs to developing populations, and 4) consideration of the broader spectrum of cancers and other diseases preventable by HPV vaccination in women, as well as in men. Despite the huge advances already achieved, there must be ongoing efforts including international advocacy to achieve widespread-optimally universal-implementation of HPV prevention strategies in both developed and developing countries. This article summarizes information from the chapters presented in a special ICO Monograph 'Comprehensive Control of HPV Infections and Related Diseases' Vaccine Volume 30, Supplement 5, 2012. Additional details on each subtopic and full information regarding the supporting literature references may be found in the original chapters.

Combined CADM1/MAL methylation and cytology testing for colposcopy triage of high-risk HPV-positive women

Primary screening for high-risk human papillomavirus (hrHPV) requires a triage protocol. Repeat cytology testing at baseline and after 6 to 12 months has emerged as a reasonable triage approach, but carries the risk of loss to follow-up. Repeat cytology testing may be omitted if cytology is supplemented with another, complementary triage test at baseline. In this study, the performance of combined triage by cytology and DNA methylation analysis was assessed. In hrHPV-positive cervical scrapes (n = 250), cytology [threshold: atypical squamous cells of undetermined significance (ASCUS)], bi-marker CADM1/MAL methylation testing (at different assay thresholds), and combinations of both were evaluated for endpoints cervical intraepithelial neoplasia grade 2 or worse (CIN2(+)) and grade 3 or worse (CIN3(+)). At a predefined methylation threshold of 70% specificity for CIN3(+), combined triage revealed a CIN3(+) sensitivity of 86.8% [95% confidence interval (CI), 76.1-97.6] compared with 65.8% (95% CI, 50.7-80.9) for sole cytology triage testing. Corresponding CIN3(+) specificity was 64.8% (95% CI, 58.1-71.5) for combined triage and 78.6% (95% CI, 72.8-84.3) for sole cytology triage testing. For CIN2(+), the sensitivity of combined triage testing was 84.5% (95% CI, 75.2-93.8) compared with 65.5% (95% CI, 53.3-77.7) for sole cytology triage, with corresponding specificities of 69.9% (95% CI, 63.1-76.6) and 83.5% (95% CI, 78.0-89.0), respectively. In conclusion, combined triage reached substantially higher CIN2(+)/3(+) sensitivities compared with sole cytology at a slight drop in specificity. Therefore, it is an attractive triage strategy for colposcopy of hrHPV-positive women with a high reassurance for cervical cancer and advanced CIN lesions.

Comprehensive control of human papillomavirus infections and related diseases

Infection with human papillomavirus (HPV) is recognized as one of the major causes of infection-related cancer worldwide, as well as the causal factor in other diseases. Strong evidence for a causal etiology with HPV has been stated by the International Agency for Research on Cancer for cancers of the cervix uteri, penis, vulva, vagina, anus and oropharynx (including base of the tongue and tonsils). Of the estimated 12.7 million new cancers occurring in 2008 worldwide, 4.8% were attributable to HPV infection, with substantially higher incidence and mortality rates seen in developing versus developed countries. In recent years, we have gained tremendous knowledge about HPVs and their interactions with host cells, tissues and the immune system; have validated and implemented strategies for safe and efficacious prophylactic vaccination against HPV infections; have developed increasingly sensitive and specific molecular diagnostic tools for HPV detection for use in cervical cancer screening; and have substantially increased global awareness of HPV and its many associated diseases in women, men, and children. While these achievements exemplify the success of biomedical research in generating important public health interventions, they also generate new and daunting challenges: costs of HPV prevention and medical care, the implementation of what is technically possible, socio-political resistance to prevention opportunities, and the very wide ranges of national economic capabilities and health care systems. Gains and challenges faced in the quest for comprehensive control of HPV infection and HPV-related cancers and other disease are summarized in this review. The information presented may be viewed in terms of a reframed paradigm of prevention of cervical cancer and other HPV-related diseases that will include strategic combinations of at least four major components: 1) routine introduction of HPV vaccines to women in all countries, 2) extension and simplification of existing screening programs using HPV-based technology, 3) extension of adapted screening programs to developing populations, and 4) consideration of the broader spectrum of cancers and other diseases preventable by HPV vaccination in women, as well as in men. Despite the huge advances already achieved, there must be ongoing efforts including international advocacy to achieve widespread-optimally universal-implementation of HPV prevention strategies in both developed and developing countries. This article summarizes information from the chapters presented in a special ICO Monograph 'Comprehensive Control of HPV Infections and Related Diseases' Vaccine Volume 30, Supplement 5, 2012. Additional details on each subtopic and full information regarding the supporting literature references may be found in the original chapters.

No evidence for a protective effect of naturally induced HPV antibodies on subsequent anogenital HPV infection in HIV-negative and HIV-infected MSM

OBJECTIVES

To assess whether HPV serum antibodies detected after natural infection protect against subsequent anal or penile infection with the same HPV type in HIV-negative and HIV-infected men who have sex with men (MSM).

METHODS

MSM aged ≥18 years were recruited in Amsterdam, the Netherlands (2010-2011), and followed-up semi-annually. Antibodies against 7 high-risk HPV types in baseline serum samples were tested using a multiplex immunoassay; baseline, 6-, and 12-month anal and penile samples were tested for HPV DNA and genotyped using the SPF10-PCR DEIA/LiPA25 system (version 1). Statistical analyses were performed using the Wei-Lin-Weissfeld method.

RESULTS

719 MSM (median age 40 years; IQR 35-48) with baseline and follow-up data were included in these analyses; 287 (40%) were HIV-infected. HPV seropositivity at baseline was not significantly associated with subsequent type-specific HPV infection at 6 or 12 months in multivariable analyses (for anal infection adjusted hazard ratio (aHR) 1.2; 95% CI 0.9-1.6; for penile infection aHR 0.8; 95% CI 0.6-1.2). High antibody concentrations showed no protective effect against subsequent infection either.

CONCLUSIONS

In a population of highly sexually active, adult MSM, naturally induced HPV antibodies may not protect MSM against subsequent anal or penile HPV infection within one year.

Six-month incidence and persistence of oral HPV infection in HIV-negative and HIV-infected men who have sex with men

Objectives

Our aim was to assess incidence and persistence of oral HPV infection in HIV-negative and HIV-infected men who have sex with men (MSM).

Methods

MSM aged ≥18 years were included in Amsterdam (the Netherlands) in 2010–2011, and followed up 6 months later. Participants completed risk factor questionnaires. HPV DNA was analyzed in oral-rinse and gargle specimens using the SPF₁₀-PCR DEIA/LiPA₂₅ system (version 1). A subset of oral samples was subjected to SPF₁₀ sequencing to identify additional HPV types. Multivariable logistic regression analyses using generalized estimating equations (GEE) were performed to assess determinants for oral high-risk HPV incidence and persistence.

Results

689/795 participant MSM provided both baseline and 6-month data. Baseline prevalence of high-risk HPV was 9.4% in HIV-negative and 23.9% in HIV-infected MSM (P<0.001). 56/689 MSM acquired ≥1 high-risk HPV infection (6-month incidence 8.1%; 95%CI 6.2–10.4%); incidence was 4.1% in HIV-negative and 14.1% in HIV-infected MSM (P<0.001). HIV infection and recent use of cannabis were both independently associated with high-risk HPV incidence. Persistent high-risk HPV was observed in 48/130 (36.9%) infections.

Conclusion

Incidence of oral high-risk HPV infection in MSM is substantial, and is associated with HIV infection. Over a third of HPV infections persisted over a 6-month period.

Clinical implications of (epi)genetic changes in HPV-induced cervical precancerous lesions

Infection of cervical epithelium with high-risk human papilloma virus (hrHPV) might result in productive or transforming cervical intraepithelial neoplasia (CIN) lesions, the morphology of which can overlap. In transforming CIN lesions, aberrations in host cell genes accumulate over time, which is necessary for the ultimate progression to cancer. On the basis of (epi)genetic changes, early and advanced transforming CIN lesions can be distinguished. This paves the way for new molecular tools for cervical screening, diagnosis and management of cervical cancer precursor lesions.

Population- and type-specific clustering of multiple HPV types across diverse risk populations in the Netherlands

In view of possible type replacement upon introduction of human papillomavirus (HPV) vaccination, we aimed to explore patterns of type-specific clustering across populations with various background infection risks. A total of 3,874 women from 3 cross-sectional studies in the Netherlands (in 2007-2009) provided vaginal self-samples, which were tested for 25 HPV genotypes by a sensitive molecular assay (SPF10 line probe assay, DDL Diagnostic Laboratory, Voorburg, the Netherlands). The number of concurrent HPV infections per woman was studied by Poisson regression. Associations between HPV types were investigated by generalized estimating equation analyses. The prevalence of any HPV type was 14% in a population-based study, 54% in a chlamydia screening intervention study, and 73% in a study among attendees of sexually transmitted infection clinics. Overall, multiple HPV infections were detected in 26% of the women. The number of concurrent HPV infections conformed to an overdispersed Poisson distribution, even after correction for known risk factors. Types differed significantly in their tendencies to be involved in coinfections, but no evidence for particular type-type interactions was found. Moreover, the strongest associations were observed in the lowest-risk population and vice versa.We found no indications of pairwise interactions, but our findings do suggest that clustering differs among HPV types and varies across risk groups.

Early detection of CIN3 and cervical cancer during long-term follow-up using HPV/Pap smear co-testing and risk-adapted follow-up in a locally organised screening programme

We evaluated compliance with human papillomavirus (HPV) testing and risk-adapted patient pathways and monitored changes in high-grade cervical disease during long-term follow-up. Women aged >30 years attending routine screening for cervical cancer were managed according to results from first-round screening tests (cytology and high-risk HPV; Hybrid Capture 2). Between February 2006 and January 2011, 19,795 of 19,947 women agreed to participate, of whom 4,067 proceeded to a second screening round 5 years after recruitment. Predefined endpoints were compliance, grade 3 cervical intraepithelial neoplasia or cancer (CIN3+), new HPV infection, HPV persistence and abnormal smears in round 2. A total of 765 of 19,795 women (3.9%) in round 1 and 41 of 4,067 (1.0%) in round 2 were referred for colposcopy. Compliance rates with colposcopy were 93.1 and 92.7%, respectively, while histological assessment was performed in 680 of 712 (95.5%) and 36 of 38 (94.7%), respectively. CIN3+ rates were 172 of 19,795 (0.87%; 95% confidence intervals: 0.7-1.0) in round 1 and 2 of 4,064 (0.05%; 95% confidence intervals: 0.006-0.2) in round 2; the difference was statistically significant (Fisher's exact test, p<0.001). After 5 years, the incidence of new HPV infection was 124 of 3,906 (3.2%) and HPV persistence was observed in 22 of 161 (13.7%). Locally organised HPV/cytology co-testing is feasible and acceptable to women. Risk-adapted management rapidly detected a high rate of prevalent CIN3+, while the subsequent long-term risk of new high-grade cervical disease was surprisingly low. It remains unclear if this phenomenon is explained by CIN3 mostly occurring early in life or by modifying the natural course of HPV infection with colposcopy and histological assessment.

Efficacy of HPV-based screening for prevention of invasive cervical cancer: follow-up of four European randomised controlled trials

BACKGROUND

In four randomised trials, human papillomavirus (HPV)-based screening for cervical cancer was compared with cytology-based cervical screening, and precursors of cancer were the endpoint in every trial. However, direct estimates are missing of the relative efficacy of HPV-based versus cytology-based screening for prevention of invasive cancer in women who undergo regular screening, of modifiers (eg, age) of this relative efficacy, and of the duration of protection. We did a follow-up study of the four randomised trials to investigate these outcomes.

METHODS

176,464 women aged 20-64 years were randomly assigned to HPV-based (experimental arm) or cytology-based (control arm) screening in Sweden (Swedescreen), the Netherlands (POBASCAM), England (ARTISTIC), and Italy (NTCC). We followed up these women for a median of 6·5 years (1,214,415 person-years) and identified 107 invasive cervical carcinomas by linkage with screening, pathology, and cancer registries, by masked review of histological specimens, or from reports. Cumulative and study-adjusted rate ratios (experimental vs control) were calculated for incidence of invasive cervical carcinoma.

FINDINGS

The rate ratio for invasive cervical carcinoma among all women from recruitment to end of follow-up was 0·60 (95% CI 0·40-0·89), with no heterogeneity between studies (p=0·52). Detection of invasive cervical carcinoma was similar between screening methods during the first 2·5 years of follow-up (0·79, 0·46-1·36) but was significantly lower in the experimental arm thereafter (0·45, 0·25-0·81). In women with a negative screening test at entry, the rate ratio was 0·30 (0·15-0·60). The cumulative incidence of invasive cervical carcinoma in women with negative entry tests was 4·6 per 10(5) (1·1-12·1) and 8·7 per 10(5) (3·3-18·6) at 3·5 and 5·5 years, respectively, in the experimental arm, and 15·4 per 10(5) (7·9-27·0) and 36·0 per 10(5) (23·2-53·5), respectively, in the control arm. Rate ratios did not differ by cancer stage, but were lower for adenocarcinoma (0·31, 0·14-0·69) than for squamous-cell carcinoma (0·78, 0·49-1·25). The rate ratio was lowest in women aged 30-34 years (0·36, 0·14-0·94).

INTERPRETATION

HPV-based screening provides 60-70% greater protection against invasive cervical carcinomas compared with cytology. Data of large-scale randomised trials support initiation of HPV-based screening from age 30 years and extension of screening intervals to at least 5 years.

FUNDING

European Union, Belgian Foundation Against Cancer, KCE-Centre d'Expertise, IARC, The Netherlands Organisation for Health Research and Development, the Italian Ministry of Health.

Methylation marker analysis of self-sampled cervico-vaginal lavage specimens to triage high-risk HPV-positive women for colposcopy

Methylation markers were studied for their suitability to triage human papillomavirus (HPV)-positive women by testing self-collected cervico-vaginal lavage specimens. For this purpose, we analyzed 355 hrHPV-positive self-collected specimens with three methylation markers, that is, CADM1-m18, MAL-m1 and miR-124-2 by quantitative methylation-specific PCR. The areas under the receiver-operating characteristic (ROC) curve for end-point cervical intraepithelial neoplasia grade 3 or worse (CIN3+) were 0.637 for CADM1-m18, 0.767 for MAL-m1 and 0.762 for miR-124-2. This indicates that CADM1-m18 is not suitable as single marker. By varying the thresholds of both markers in the bi-marker panels CADM1-m18/MAL-m1, CADM1-m18/miR-124-2 and MAL-m1/miR-124-2 upper and lower ROC curves were obtained, depicting the maximum and minimum CIN3+ sensitivity, respectively, at given specificity. For all these bi-marker combinations, the upper curves were similar. However, for the MAL-m1/miR-124-2 panel, the distance between upper and lower ROC curves was closest and this panel displayed the highest assay thresholds, indicating that this combination was most robust. At clinical specificities of 50 and 70%, the MAL-m1/miR-124-2 sensitivity for detection of CIN3+ ranged from 77.0 to 87.8% and from 64.9 to 71.6%, respectively. At 70% specificity thresholds no carcinomas were missed. By comparison, the CIN3+ sensitivity of HPV16/18 genotyping on the self-sampled lavage specimens was 58.1% (95%CI: 46.6-68.8) at a specificity of 87.7% (95%CI: 83.2-91.2). In conclusion, methylation analysis is a promising triage tool that in combination with HPV-DNA testing offers feasible, full molecular screening on self-collected cervico-vaginal lavage specimens.

Comprehensive control of human papillomavirus infections and related diseases

Infection with human papillomavirus (HPV) is recognized as one of the major causes of infection-related cancer worldwide, as well as the causal factor in other diseases. Strong evidence for a causal etiology with HPV has been stated by the International Agency for Research on Cancer for cancers of the cervix uteri, penis, vulva, vagina, anus and oropharynx (including base of the tongue and tonsils). Of the estimated 12.7 million new cancers occurring in 2008 worldwide, 4.8% were attributable to HPV infection, with substantially higher incidence and mortality rates seen in developing versus developed countries. In recent years, we have gained tremendous knowledge about HPVs and their interactions with host cells, tissues and the immune system; have validated and implemented strategies for safe and efficacious prophylactic vaccination against HPV infections; have developed increasingly sensitive and specific molecular diagnostic tools for HPV detection for use in cervical cancer screening; and have substantially increased global awareness of HPV and its many associated diseases in women, men, and children. While these achievements exemplify the success of biomedical research in generating important public health interventions, they also generate new and daunting challenges: costs of HPV prevention and medical care, the implementation of what is technically possible, socio-political resistance to prevention opportunities, and the very wide ranges of national economic capabilities and health care systems. Gains and challenges faced in the quest for comprehensive control of HPV infection and HPV-related cancers and other disease are summarized in this review. The information presented may be viewed in terms of a reframed paradigm of prevention of cervical cancer and other HPV-related diseases that will include strategic combinations of at least four major components: 1) routine introduction of HPV vaccines to women in all countries, 2) extension and simplification of existing screening programs using HPV-based technology, 3) extension of adapted screening programs to developing populations, and 4) consideration of the broader spectrum of cancers and other diseases preventable by HPV vaccination in women, as well as in men. Despite the huge advances already achieved, there must be ongoing efforts including international advocacy to achieve widespread-optimally universal-implementation of HPV prevention strategies in both developed and developing countries. This article summarizes information from the chapters presented in a special ICO Monograph 'Comprehensive Control of HPV Infections and Related Diseases' Vaccine Volume 30, Supplement 5, 2012. Additional details on each subtopic and full information regarding the supporting literature references may be found in the original chapters.

DNA copy number aberrations in endobronchial lesions: a validated predictor for cancer

We recently identified a DNA copy number aberration (CNA)-based classifier, including changes at 3p26.3-p11.1, 3q26.2-29, and 6p25.3-24.3, as a risk predictor for cancer in individuals presenting with endobronchial squamous metaplasia. The current study was set out to validate the prediction accuracy of this classifier in an independent series of endobronchial squamous metaplastic and dysplastic lesions. The study included 36 high-risk subjects who had endobronchial lesions of various histological grades that were identified and biopsied by autofluorescence bronchoscopy and were subjected to arrayCGH in a nested case-control design. Of the 36 patients, 12 had a carcinoma in situ or invasive carcinoma at the same site at follow-up (median 11 months, range 4-24), while 24 controls remained cancer free (78 months, range 21-142). The previously defined CNA-based classifier demonstrated 92% (95% CI 77% to 98%) accuracy for cancer (in situ) prediction. All nine subjects with CNA-based classifier-positive endobronchial lesions at baseline experienced cancer outcome, whereas all 24 controls and 3 cases were classified as being low risk. In conclusion, CNAs prove to be a highly accurate biomarker for assessing the progression risk of endobronchial squamous metaplastic and dysplastic lesions. This classifier could assist in selecting subjects with endobronchial lesions who might benefit from more aggressive therapeutic intervention or surveillance.

Clinical progression of high-grade cervical intraepithelial neoplasia: estimating the time to preclinical cervical cancer from doubly censored national registry data

Little is known about the time span of progression from high-grade cervical intraepithelial neoplasia (CIN2/3) to invasive cervical cancer. Estimation of this duration from longitudinal studies is not permitted, as CIN2/3 should be treated when detected. Cross-sectional data on the age-specific incidence of detected CIN2/3 and cervical cancer cases are readily available in national registries, but these data are difficult to interpret because neither the moment of lesion development nor the onset of invasive cancer is observed. We developed a statistical model for estimating the duration of time between CIN2/3 and preclinical cancer using Dutch national registries for the years 2000-2005. Human papillomavirus (HPV) genotype data were used to separate CIN2/3 and cancer incidences to obtain estimates for HPV-16-positive and HPV-16-negative lesions. The median time from CIN2/3 to cancer was estimated to be 23.5 years (95% confidence interval: 20.8, 26.6), and 1.6% of the lesions progressed to cancer within 10 years. The median duration for HPV-16-positive lesions was similar, but 2.4% of the HPV-16-positive lesions progressed to cancer within 10 years, as compared with 0.6% for HPV-16-negative lesions. Estimated durations of time to cancer are essential for reassessment of the optimal screening interval in light of vaccination and novel screening tests.

Characteristics of HPV-specific antibody responses induced by infection and vaccination: cross-reactivity, neutralizing activity, avidity and IgG subclasses

OBJECTIVES

In order to assess HPV-specific IgG characteristics, we evaluated multiple aspects of the humoral antibody response that will provide insight in the HPV humoral immune response induced by HPV infection and vaccination.

METHODS

Cross-reactivity of HPV-specific antibodies induced by infection or vaccination was assessed with VLP16 or 18 inhibition using a VLP-based multiplex immunoassay (MIA) for HPV16, 18, 31, 33, 45, 52 and 58. HPV16/18 specific IgG1-4 subclasses and avidity were determined with the VLP-MIA in sera after HPV infection and after vaccination. Neutralizing antibodies were determined in a small subset of single-seropositive and multi-seropositive naturally derived antibodies.

RESULTS

Naturally derived antibodies from single-positive sera were highly genotype-specific as homologue VLP-inhibition percentages varied between 78-94%. In multi-positive sera, cross-reactive antibodies were observed both within and between α7 and α9 species. After vaccination, cross-reactive antibodies were mainly species-specific. Avidity of vaccine-derived HPV-specific antibodies was 3 times higher than that of antibodies induced by HPV infection (p<0.0001). IgG1 and IgG3 were found to be the predominant subclasses observed after HPV infection and vaccination. In the small subset tested, the number of single-positive sera with neutralizing capacity was higher than of multi-positive sera.

CONCLUSION

Naturally derived HPV-specific antibodies from single-positive samples showed different characteristics in terms of cross-reactivity and neutralizing capacity compared with antibodies from multi-positive sera. Post-vaccination, HPV antibody avidity was approximately 3 times higher than antibody avidity induced by HPV infection. Therefore, antibody avidity might be a potential surrogate of protection.