Comparing the performance of FAM19A4 methylation analysis,cytology and HPV16/18 genotyping for the detection of cervical (pre)cancer in high‐risk HPV‐positive women of a gynecologic outpatient population (COMETH study)

Recently, DNA methylation analysis of FAM19A4 in cervical scrapes has been shown to adequately detect high‐grade cervical intraepithelial neoplasia and cervical cancer (≥CIN3) in high‐risk HPV (hrHPV)‐positive women. Here, we compared the clinical performance of FAM19A4 methylation analysis to cytology and HPV16/18 genotyping, separately and in combination, for ≥CIN3 detection in hrHPV‐positive women participating in a prospective observational multi‐center cohort study. The study population comprised hrHPV‐positive women aged 18–66 years, visiting a gynecological outpatient clinic. From these women, cervical scrapes and colposcopy‐directed biopsies (for histological confirmation) were obtained. Cervical scrapes were analyzed for FAM19A4 gene promoter methylation, cytology and HPV16/18 genotyping. Methylation analysis was performed by quantitative methylation‐specific PCR (qMSP). Sensitivities and specificities for ≥CIN3 were compared between tests. Stratified analyses were performed for variables that potentially influence marker performance. Of all 508 hrHPV‐positive women, the sensitivities for ≥CIN3 of cytology, FAM19A4 methylation analysis, and cytology combined with HPV16/18 genotyping were 85.6, 75.6 and 92.2%, respectively, with corresponding specificities of 49.8, 71.1 and 29.4%, respectively. Both sensitivity and specificity of FAM19A4 methylation analysis were associated with age (p ≤ 0.001 each). In women ≥30 years (n = 287), ≥CIN3 sensitivity of FAM19A4 methylation analysis was 88.3% (95%CI: 80.2–96.5) which was noninferior to that of cytology [85.5% (95%CI: 76.0–94.0)], at a significantly higher specificity [62.1% (95%CI: 55.8–68.4) compared to 47.6% (95%CI: 41.1–54.1)]. In conclusion, among hrHPV‐positive women from an outpatient population aged ≥30 years, methylation analysis of FAM19A4 is an attractive marker for the identification of women with ≥CIN3.     

Methylation testing for the detection of recurrent cervical intraepithelial neoplasia

Women treated for CIN2/3 remain at increased risk of recurrent CIN and cervical cancer, and therefore posttreatment surveillance is recommended. This post hoc analysis evaluates the potential of methylation markers ASCL1/LHX8 and FAM19A4/miR124-2 for posttreatment detection of recurrent CIN2/3. Cervical scrapes taken at 6 and 12 months posttreatment of 364 women treated for CIN2/3 were tested for methylation of ASCL1/LHX8 and FAM19A4/miR124-2 using quantitative multiplex methylation-specific PCR. Performance of the methylation tests were calculated and compared with the performance of HPV and/or cytology. Methylation levels of recurrent CIN were compared between women with a persistent HPV infection, and women with an incident HPV infection or without HPV infection. Recurrent CIN2/3 was detected in 42 women (11.5%), including 28 women with CIN2 and 14 with CIN3. ASCL1/LHX8 tested positive in 13/14 (92.9%) of recurrent CIN3 and 13/27 (48.1%) of recurrent CIN2. FAM19A4/miR124-2 tested positive in 14/14 (100%) of recurrent CIN3 and 10/27 (37.0%) of recurrent CIN2. Combined HPV and/or methylation testing showed similar positivity rates as HPV and/or cytology. The CIN2/3 risk at 12 months posttreatment was 30.8% after a positive ASCL1/LHX8 result at 6 months posttreatment. Methylation levels of CIN2/3 in women with a persistent HPV infection were significantly higher compared with women with an incident or no HPV infection. In conclusion, posttreatment monitoring by methylation analysis of ASCL1/LHX8 and FAM19A4/miR124-2 showed a good performance for the detection of recurrent CIN. DNA methylation testing can help to identify women with recurrent CIN that require re-treatment.     

Cervical cancer risk in HPV‐positive women after a negative FAM19A4/mir124‐2 methylation test: A post hoc analysis in the POBASCAM trial with 14 year follow‐up

DNA methylation analysis of cervical scrapes using FAM19A4 and mir124‐2 genes has shown a good clinical performance in detecting cervical cancer and advanced CIN lesions in need of treatment in HPV‐positive women. To date, longitudinal data on the cancer risk of methylation test‐negative women are lacking. In our study, we assessed the longitudinal outcome of FAM19A4/mir124‐2 methylation analysis in an HPV‐positive screening cohort with 14 years of follow‐up. Archived HPV‐positive cervical scrapes of 1,040 women (age 29–61 years), who were enrolled in the POBASCAM screening trial (ISRCTN20781131) were tested for FAM19A4/mir124‐2 methylation. By linkage with the nationwide network and registry of histo‐ and cytopathology in the Netherlands (PALGA), 35 cervical cancers were identified during 14 years of follow‐up comprising three screens (baseline, and after 5 and 10 years). The baseline scrape of 36.1% (n = 375) women tested positive for FAM19A4/mir124‐2 methylation, including 24 women with cervical cancer in follow‐up, and 30.6% (n = 318) had abnormal cytology (threshold borderline dyskaryosis or ASCUS), including 14 women with cervical cancer in follow‐up. Within screening round capability of FAM19A4/mir124‐2 methylation to detect cervical cancer was 100% (11/11, 95% CI: 71.5–100). Kaplan–Meier estimate of 14‐year cumulative cervical cancer incidence was 1.7% (95% CI: 0.66–3.0) among baseline methylation‐negative and 2.4% (95% CI: 1.4–3.6) among baseline cytology‐negative women (risk difference: 0.71% [95% CI: 0.16–1.4]). In conclusion, a negative FAM19A4/mir124‐2 methylation test provides a low cervical cancer risk in HPV‐positive women of 30 years and older. FAM19A4/mir124‐2 methylation testing merits consideration as an objective triage test in HPV‐based cervical screening programs.     

Reliable identification of women with CIN3+ using hrHPV genotyping and methylation markers in a cytology-screened referral population

Cervical screening aims to identify women with high-grade squamous intraepithelial lesion/cervical intraepithelial neoplasia 2-3 (HSIL/CIN2-3) or invasive cervical cancer (ICC). Identification of women with severe premalignant lesions or ICC (CIN3+) could ensure their rapid treatment and prevent overtreatment. We investigated high-risk human papillomavirus (hrHPV) detection with genotyping and methylation of FAM19A4/miR124-2 for detection of CIN3+ in 538 women attending colposcopy for abnormal cytology. All women had an additional cytology with hrHPV testing (GP5+/6+-PCR-EIA+), genotyping (HPV16/18, HPV16/18/31/45), and methylation analysis (FAM19A4/miR124-2) and at least one biopsy. CIN3+ detection was studied overall and in women <30 (n = 171) and ≥30 years (n = 367). Positivity for both rather than just one methylation markers increased in CIN3, and all ICC was positive for both. Overall sensitivity and specificity for CIN3+ were, respectively, 90.3% (95%CI 81.3–95.2) and 31.8% (95%CI 27.7–36.1) for hrHPV, 77.8% (95%CI 66.9–85.8) and 69.3% (95%CI 65.0–73.3) for methylation biomarkers and 93.1% (95%CI 84.8–97.0) and 49.4% (95%CI 44.8–53.9) for combined HPV16/18 and/or methylation positivity. For CIN3, hrHPV was found in 90.9% (95%CI 81.6–95.8), methylation positivity in 75.8% (95%CI 64.2–84.5) and HPV16/18 and/or methylation positivity in 92.4% (95%CI 83.5–96.7). In women aged ≥30, the sensitivity of combined HPV16/18 and methylation was increased (98.2%, 95%CI 90.6–99.7) with a specificity of 46.3% (95%CI 40.8–51.9). Combination of HPV16/18 and methylation analysis was very sensitive and offered improved specificity for CIN3+, opening the possibility of rapid treatment for these women and follow-up for women with potentially regressive, less advanced, HSIL/CIN2 lesions.     

CADM1 and MAL promoter methylation levels in hrHPV‐positive cervical scrapes increase proportional to degree and duration of underlying cervical disease

Combined detection of cell adhesion molecule 1 (CADM1) and T‐lymphocyte maturation‐associated protein (MAL) promoter methylation in cervical scrapes is a promising triage strategy for high‐risk human papillomavirus (hrHPV)‐positive women. Here, CADM1 and MAL DNA methylation levels were analysed in cervical scrapes of hrHPV‐positive women with no underlying high‐grade disease, high‐grade cervical intraepithelial neoplasia (CIN) and cervical cancer. CADM1 and MAL methylation levels in scrapes were first related to CIN‐grade of the corresponding biopsy and second to CIN‐grade stratified by the presence of ‘normal’ or ‘abnormal’ cytology as present in the accompanying scrape preceding the cervical biopsy. The scrapes included 167 women with ≤CIN1, 54 with CIN2/3 and 44 with carcinoma. In a separate series of hrHPV‐positive scrapes of women with CIN2/3 (n = 48), methylation levels were related to duration of preceding hrHPV infection (PHI; <5 and ≥5 years). Methylation levels were determined by quantitative methylation‐specific PCR and normal cytology scrapes of hrHPV‐positive women with histologically ≤CIN1 served as reference. CADM1 and MAL methylation levels increased proportional to severity of the underlying lesion, showing an increase of 5.3‐ and 6.2‐fold in CIN2/3, respectively, and 143.5‐ and 454.9‐fold in carcinomas, respectively, compared to the reference. Methylation levels were also elevated in CIN2/3 with a longer duration of PHI (i.e. 11.5‐ and 13.6‐fold, respectively). Moreover, per histological category, methylation levels were higher in accompanying scrapes with abnormal cytology than in scrapes with normal cytology. Concluding, CADM1 and MAL promoter methylation levels in hrHPV‐positive cervical scrapes are related to the degree and duration of underlying cervical disease and markedly increased in cervical cancer.     

Risk-stratification of HPV-positive women with low-grade cytology by FAM19A4/miR124-2 methylation and HPV genotyping

Background The introduction of primary HPV screening has doubled the number of colposcopy referrals because of the direct referral of HPV-positive women with a borderline or mild dyskaryosis (BMD) cytology (ASC-US/LSIL) triage test. Further risk-stratification is warranted to improve the efficiency of HPV-based screening.Methods This study evaluated the discriminative power of FAM19A4/miR124-2 methylation, HPV16/18 genotyping and HPV16/18/31/33/45 genotyping in HPV-positive women with BMD (n = 294) in two Dutch screening trials. Absolute CIN3+ risks and colposcopy referrals within one screening round were calculated.Results Methylation analysis discriminated well, yielding a CIN3+ risk of 33.1% after a positive result and a CIN3+ risk of 9.8% after a negative result. HPV16/18 and HPV16/18/31/33/45 genotyping resulted in a 27.6% and 24.6% CIN3+ risk after a positive result, and a 13.2% and 9.1% CIN3+ risk after a negative result. Colposcopy referral percentages were 41.2%, 43.2%, and 66.3% for FAM19A4/miR124-2 methylation, HPV16/18 and HPV16/18/31/33/45 genotyping, respectively. The CIN3+ risk after a negative result could be lowered to 2.8% by combining methylation and extended genotyping, at the expense of a higher referral percentage of 75.5%.Conclusion The use of FAM19A4/miR124-2 methylation and/or HPV genotyping in HPV-positive women with BMD can lead to a substantial reduction in the number of direct colposcopy referrals.Subject terms: DNA methylation, Diagnostic markers, Cervical cancer, Molecular medicine     

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.     

Validation of a DNA methylation HPV triage classifier in a screening sample

High‐risk human papillomavirus (hrHPV) DNA tests have excellent sensitivity for detection of cervical intraepithelial neoplasia 2 or higher (CIN2+). A drawback of hrHPV screening, however, is modest specificity. Therefore, hrHPV‐positive women might need triage to reduce adverse events and costs associated with unnecessary colposcopy. We compared the performance of HPV16/18 genotyping with a predefined DNA methylation triage test (S5) based on target regions of the human gene EPB41L3, and viral late gene regions of HPV16, HPV18, HPV31 and HPV33. Assays were run using exfoliated cervical specimens from 710 women attending routine screening, of whom 38 were diagnosed with CIN2+ within a year after triage to colposcopy based on cytology and 341 were hrHPV positive. Sensitivity and specificity of the investigated triage methods were compared by McNemar's test. At the predefined cutoff, S5 showed better sensitivity than HPV16/18 genotyping (74% vs 54%, P = 0.04) in identifying CIN2+ in hrHPV‐positive women, and similar specificity (65% vs 71%, P = 0.07). When the S5 cutoff was altered to allow equal sensitivity to that of genotyping, a significantly higher specificity of 91% was reached (P < 0.0001). Thus, a DNA methylation test for the triage of hrHPV‐positive women on original screening specimens might be a valid approach with better performance than genotyping.     

Discovery and validation of candidate host DNA methylation markers for detection of cervical precancer and cancer

Human papillomavirus (HPV) testing has been recently introduced as an alternative to cytology for cervical cancer screening. However, since most HPV infections clear without causing clinically relevant lesions, additional triage tests are required to identify women who are at high risk of developing cancer. We performed DNA methylation profiling on formalin‐fixed, paraffin‐embedded tissue specimens from women with benign HPV16 infection and histologically confirmed cervical intraepithelial neoplasia grade 3, and cancer using a bead‐based microarray covering 1,500 CpG sites in over 800 genes. Methylation levels in individual CpG sites were compared using a t‐test, and results were summarized by computing p‐values. A total of 12 candidate genes (ADCYAP1, ASCL1, ATP10, CADM1, DCC, DBC1, HS3ST2, MOS, MYOD1, SOX1, SOX17 and TMEFF2) identified by DNA methylation profiling, plus an additional three genes identified from the literature (EPB41L3, MAL and miR‐124) were chosen for validation in an independent set of 167 liquid‐based cytology specimens using pyrosequencing and targeted, next‐generation bisulfite sequencing. Of the 15 candidate gene markers, 10 had an area under the curve (AUC) of ≥ 0.75 for discrimination of high grade squamous intraepithelial lesions or worse (HSIL+) from <HSIL cytology using at least one assay. Overall, SOX1, DCC, and EPB41L3 showed the best discrimination with AUC values of ≥0.80, irrespective of methylation detection assay. In addition to verifying candidate markers from the literature (e.g., SOX1 and EPB41L3), we identified novel markers that may be considered for detection of cervical precancer and cancer and warrant further validation in prospective studies.     

DNA methylation markers as a triage test for identification of cervical lesions in a high risk human papillomavirus positive screening cohort

Objective triage strategies are required to prevent unnecessary referrals for colposcopy in population-based screening programs using primary high-risk human papillomavirus (hrHPV) testing. We have identified several DNA methylation markers with high sensitivity and specificity for detection of high-grade cervical intraepithelial neoplasia or worse (CIN2+) in women referred for colposcopy. Our study assessed diagnostic potential of these methylation markers in a hrHPV-positive screening cohort. All six markers (JAM3, EPB41L3, C13orf18, ANKRD18CP, ZSCAN1 and SOX1) showed similar association across histology in the hrHPV-positive cohort when compared to the Dutch cohort (each p > 0.15). Sensitivity for CIN2+ was higher using methylation panel C13orf18/EPB41L3/JAM3 compared to the other 2 panels (80% vs. 60% (ANKRD18CP/C13orf18/JAM3) and 63% (SOX1/ZSCAN1), p = 0.01). For CIN3+ all three methylation panels showed comparable sensitivity ranging from 68% (13/19) to 95% (18/19). Specificity of SOX1/ZSCAN1 panel (84%, 167/200) was considerably higher compared to ANKRD18CP/C13orf18/JAM3 (68%, 136/200, p = 2 × 10⁻⁵) and C13orf18/EPB41L3/JAM3 (66%, 132/200, p = 2 × 10⁻⁷). High negative predictive value (NPV) (91–95% and 96–99%) was observed for CIN2+ and CIN3+, for all three methylation panels, while positive predictive value (PPV) varied from 25 to 40% for CIN2+ and 15–27% for CIN3+. Interestingly, 118/235 samples were negative for all six markers (including 106 controls (89.8%), 6 CIN1 (5.1%), 5 CIN2 (4.2%) and 1 CIN3 (0.8%)). Methylation results from both independent cohorts were comparable as well as high sensitivity for detection of cervical cancer and its high-grade precursors in hrHPV-positive population. Our study therefore validates these methylation marker panels as triage test either in hrHPV-based or abnormal cytology-based screening programs.     

High‐risk HPV testing in the management of atypical glandular cells: A systematic review and meta‐analysis

Whereas the utility of high‐risk HPV (hrHPV) testing is widely accepted in triage of women with atypical squamous lesions, its role in managing atypical glandular cells (AGC) is not fully elucidated. A systematic review and meta‐analysis were performed to evaluate the accuracy of hrHPV testing in the management of women with AGC to detect underlying high‐grade intraepithelial neoplasia or worse, and adenocarcinoma in situ or worse (AIS+). Additionally, the diagnosis of extra‐cervical cancer was considered as an outcome in this review. A bibliographic database search (PubMed, EMBASE, CENTRAL) identified twelve eligible studies. The occurrence of cervical intraepithelial neoplasia grade two or worse including AIS+ (CIN2+/AIS+), was 19.8% among women with AGC, and 55.7% among women with AGC and concurrent squamous lesions (atypical squamous cells of undetermined significance or worse, ASC‐US+). The pooled sensitivity and specificity of hrHPV‐testing with Hybrid Capture 2 (HC2) to detect CIN2+/AIS+ in women with AGC was 90.0% (95% CI = 85.1–93.4%) and 75.1% (95% CI = 64.8–83.2%), respectively. Women who were hrHPV‐negative, demonstrated an increased risk for extra‐cervical malignancy (endometrium, fallopian tube, ovary). In women of 50y and older, a hrHPV‐negative result was linked with a 18.0% chance of extra‐cervical malignancy, while the chance of cervical pre‐cancer and cancer was 0.4 and 0.0%, respectively. In conclusion, given the high risk of underlying CIN2+/AIS+, women with AGC should be referred directly to colposcopy. However, hrHPV test results in combination with the age, appears to improve the diagnostic process by distinguishing the risk for cervical versus non‐cervical lesions.     

A DNA methylation classifier of cervical precancer based on human papillomavirus and human genes

Testing for high‐risk (hr) types of human papillomavirus (HPV) is highly sensitive as a screening test of high‐grade cervical intraepithelial neoplastic (CIN2/3) disease, the precursor of cervical cancer. However, it has a relatively low specificity. Our objective was to develop a prediction rule with a higher specificity, using combinations of human and HPV DNA methylation. Exfoliated cervical specimens from colposcopy‐referral cohorts in London were analyzed for DNA methylation levels by pyrosequencing in the L1 and L2 regions of HPV16, HPV18, HPV31 and human genes EPB41L3, DPYS and MAL. Samples from 1,493 hrHPV‐positive women were assessed and of these 556 were found to have CIN2/3 at biopsy; 556 tested positive for HPV16 (323 CIN2/3), 201 for HPV18 (73 CIN2/3) and 202 for HPV31 (98 CIN2/3). The prediction rule included EPB41L3 and HPV and had area under curve 0.80 (95% CI 0.78–0.82). For 90% sensitivity, specificity was 36% (33–40) and positive predictive value (PPV) was 46% (43–48). By HPV type, 90% sensitivity corresponded to the following specificities and PPV, respectively: HPV16, 38% (32–45) and 67% (63–71); HPV18, 53% (45–62) and 52% (45–59); HPV31, 39% (31–49) and 58% (51–65); HPV16, 18 or 31, 44% (40–49) and 62% (59–65) and other hrHPV 17% (14–21) and 21% (18–24). We conclude that a methylation assay in hrHPV‐positive women might improve PPV with minimal sensitivity loss.     

Evaluation of a validated methylation triage signature for human papillomavirus positive women in the HPV FOCAL cervical cancer screening trial

Human papillomavirus (HPV)-based cervical cancer screening requires triage of HPV positive women to identify those at risk of cervical intraepithelial neoplasia grade 2 (CIN2) or worse. We conducted a blinded case–control study within the HPV FOCAL randomized cervical cancer screening trial of women aged 25–65 to examine whether baseline methylation testing using the S5 classifier provided triage performance similar to an algorithm relying on cytology and HPV genotyping. Groups were randomly selected from women with known HPV/cytology results and pathology outcomes. Group 1: 104 HPV positive (HPV+), abnormal cytology (54 CIN2/3; 50 <CIN2); Group 2: 103 HPV+, normal cytology with HPV persistence at 12 mo. (53 CIN2/3; 50 <CIN2); Group 3: 50 HPV+, normal cytology with HPV clearance at 12 mo. (assumed <CIN2), total n=257. For the combined groups, S5 risk score CIN2/3 relative sensitivity, specificity and positive predictive value (PPV) were compared with other triage approaches. Methylation showed a highly significant increasing trend with disease severity. For CIN3, S5 relative sensitivity and specificity were: 93.2% (95%CI: 81.4–98.0) and 41.8% (35.2–48.8), compared to 86.4% (75.0–95.7) and 49.8% (43.1–56.6) respectively for combined abnormal cytology/HPV16/18 positivity (differences not statistically significant at 5% level); adjusted PPVs were 18.2% (16.2–20.4) and 19.3% (16.6–22.2) respectively. S5 was also positive in baseline specimens from eight cancers detected during or after trial participation. The S5 methylation score had high sensitivity and PPV for CIN3, compatible with US and European thresholds for colposcopy referral. Methylation signatures can identify most HPV positive women at increased risk of cervical cancer from their baseline screening specimens.     

Association between RASSF1A Promoter Hypermethylation and Oncogenic HPV Infection Status in Invasive Cervical Cancer: a Meta-analysis

Cervical carcinoma is the main cause of cancer-related mortality in women and is correlated with more than15 risk cofactors, including infection of cervical cells with high-risk types of HPV (hrHPV). Indeed, both aberrantmethylation of the RASSF1A promoter and hrHPV infection are often observed in cervical carcinomas. Thepurpose of our meta-analysis was to evaluate the role of RASSF1A promoter methylation and hrHPV infectionin cervical cancer. Our meta-analysis involved 895 cervical cancer patients and 454 control patients from 15studies. Our results suggested that RASSF1A promoter hypermethylation increased the risk of cervical cancer(OR=9.77, 95%CI=[3.06, 31.26], P=0.0001, I2=78%). By grouping cases according to cancer subtypes, we foundthat HPV infection was higher in cervical squamous cell carcinomas (SCCs) than in cervical adenocarcinomas/adenosquamous cancers (ACs/ASCs) (OR=4.00, 95%CI=[1.41, 11.30], P=0.009, I2=55%). Interestingly, HPVinfection tended to occur in cervical cancers with relatively low levels of RASSF1A promoter methylation(OR=0.59, 95%CI=[0.36, 0.99], P=0.05, I2=0%). Our study provides evidence of a possible interaction betweenHPV infection and RASSF1A promoter methylation in the development of cervical cancers.     

The current position and the future perspectives of cervical cancer screening

Cervical screening programs for detecting cancer and precancer have dramatically reduced the incidence and mortality rates of cervical cancer since the 1960s. The efficacy of the screening programs depends on participation and the accuracy of the screening tests. Unfortunately, the participation rates are suboptimal; more than half the women with cervical cancer have not or have only sporadically been screened. Increasing participation is the best way of maximizing the program’s benefit. Furthermore, cytology screening lacks high sensitivity for high-grade cervical intraepithelial neoplasia (≥CIN2). High-risk human papillomavirus (hrHPV) screening is more sensitive in the detection of cervical intraepithelial neoplasia than cytology screening, but less specific, so that additional triage testing is still mandatory. The aim of this article is to reflect on the efficacy of current cervical cancer screening and on promising future screening strategies with primary hrHPV testing and additional triage strategies for hrHPV-positive screening results.     

JAM3 methylation status as a biomarker for diagnosis of preneoplastic and neoplastic lesions of the cervix

DNA methylation is clinically relevant to important tumorigenic mechanisms. This study evaluated the methylation status of candidate genes in cervical neoplasia and determined their diagnostic performance in clinical practice. Cervical cancer and normal cervix tissue was used to select the top 5 discriminating loci among 27 loci in 4 genes (CCNA1, CADM1, DAPK1, JAM3), and one locus of JAM3 (region M4) was identified and confirmed with 267 and 224 cervical scrapings from 2 independent colposcopy referral studies. For patients with atypical squamous cells of unknown significance and those with low-grade squamous intraepithelial lesion, with JAM3-M4 compared to a triage marker of hrHPV testing, the specificity for cervical intraepithelial neoplasia 3 CIN3 and cancer cases (CIN3+) / no neoplasia and CIN1 (CIN1−) was significantly increased, from 21.88 to 81.82 and 15.38 to 85.18, respectively. The corresponding positive predictive value (PPV) was increased from 26.47 to 57.14 and 18.52 to 63.64, respectively. For hrHPV-positive patients, compared to a triage marker of cytology testing, JAM3-M4 showed increased specificity and PPV, from 30.67 to 87.65 and 38.82 to 82.14, respectively. We assessed whether JAM3-M4 could distinguish productive from transforming CIN2; the coincidence rate of JAM3-M4 and P16 was as high as 60.5%.     

LINE-1 and Alu Methylation in hrHPV-Associated Precancerous Cervical Samples

Objective: This study was conducted to determine global DNA methylation patterns in cervical cells cytologically identified as atypical squamous cells of unknown significance (ASCUS) with a normal, LSIL, or HSIL histopathological result. Methods: Methylation patterns of long interspersed nuclear elements (LINE-1) and short interspersed element (Alu) sequences were assessed using the combined bisulfite restriction analysis (COBRA) method in cervical samples with cytology-diagnosed cervical lesions. Results: In cervical precancerous lesions with hrHPV positive, the percentage of overall (mC) and mCmC LINE-1 methylation levels showed a stepwise increase from hrHPV positive normal to HSIL with significant differences (p<0.001). However, both methylation levels were significantly higher in hrHPV negative normal than in hrHPV positive normal (p<0.001). The overall (mC) Alu methylation in hrHPV positive LSIL and HSIL was lower than in hrHPV positive normal, with a significant difference (p<0.05). Remarkably, the percentage of uCmC and mCuC of LINE-1 and Alu in three different hrHPV positive cervical lesions showed a stepwise decrease from hrHPV positive normal, LSIL and HSIL, respectively. Furthermore, receiver operating characteristic (ROC) curve analyses revealed that the LINE-1 mC and mCmC patterns have high sensitivity and specificity for distinguishing HSIL from normal/LSIL in hrHPV positive cases at the appropriate cutoff levels. Conclusion: We have demonstrated the LINE-1 and Alu methylation data in normal and premalignant cervical epithelia. LINE-1 hypomethylation was found in hrHPV positive normal cells, with lower methylation levels associated with cancer features. In cytologically diagnosed Atypical Squamous Cells of Unknown Significance (ASCUS), the levels of mC and the mCmC pattern could be utilized in concert with hrHPV detection to classify the ASCUS sample prior to colposcopy.     

Triage of high-risk HPV positive women in cervical cancer screening

Introduction: High-risk human papillomavirus (hrHPV) testing is expected to replace cytology as primary screening method for cervical cancer screening in an increasing number of countries. The high sensitivity of hrHPV testing is combined with a limited specificity which makes triaging of hrHPV positive women necessary. As an ideal triage method does not yet exist, an optimal triage strategy for hrHPV positive women based on current knowledge should be obtained. The aim of this article is to present an overview of available options for triage of hrHPV positive women, with their strengths and limitations and possible future opportunities.

Areas covered: Current knowledge on morphological biomarkers, molecular biomarkers and combined triage strategies will be discussed to give an overview of the state-of-the-art on triaging hrHPV positive women. The literature search was limited to studies on triage strategies for hrHPV positive women.

Expert commentary: Experience with morphology-based biomarkers makes these a valuable triage method. However, they lack the ability of differentiating productive from transforming infections. Molecular biomarkers are objective, highly reproducible, can be used in high throughput testing, and show promising results. With more extensive knowledge on these molecular markers, cervical cancer screening may transform to a full molecular screening in the future.     

Methylation of viral and host genes and severity of cervical lesions associated with human papillomavirus type 16

Methylation of human papillomavirus (HPV) and host genes may predict cervical cancer risk. We examined the methylation status of selected sites in HPV16 and human genes in DNA extracted from exfoliated cervical cell samples of 244 women harboring HPV16‐positive cancer or cervical intraepithelial neoplasia (CIN) or negative for intraepithelial lesions or malignancy (NILM). We quantified the methylation of CpG sites in the HPV16 L1 gene (CpG 6367 and 6389) and in the human genes EPB41L3 (CpG 438, 427, 425) and LMX1 (CpG 260, 262, 266, 274) following bisulfite treatment and pyrosequencing. Receiver operating characteristic (ROC) curves were used to analyze the diagnostic utility of methylation level for the different sites and for a joint predictor score. Methylation in all sites significantly increased with lesion severity (p < 0.0001). Area under the curve (AUC) was highest among the CIN2/3 vs. cancer ranging from 0.786 to 0.853 among the different sites. Site‐specific methylation levels strongly discriminated CIN2/3 from NILM/CIN1 and cancer from CIN2/3 (range of odds ratios [OR]: 3.69–12.76, range of lower 95% confidence bounds: 1.03–4.01). When methylation levels were mutually adjusted for each other EPB41L3 was the only independent predictor of CIN2/3 vs. NILM/CIN1 contrasts (OR = 9.94, 95%CI: 2.46–40.27). High methylation levels of viral and host genes are common among precancerous and cancer lesions and can serve as independent risk biomarkers. Methylation of host genes LMX1 and EPB41L3 and of the viral HPV16 L1 sites has the potential to distinguish among precancerous lesions and to distinguish the latter from invasive disease.     

A four-gene methylation marker panel as triage test in high-risk human papillomavirus positive patients

Cervical neoplasia‐specific biomarkers, e.g. DNA methylation markers, with high sensitivity and specificity are urgently needed to improve current population‐based screening on (pre)malignant cervical neoplasia. We aimed to identify new cervical neoplasia‐specific DNA methylation markers and to design and validate a methylation marker panel for triage of high‐risk human papillomavirus (hr‐HPV) positive patients. First, high‐throughput quantitative methylation‐specific PCRs (QMSP) on a novel OpenArray? platform, representing 424 primers of 213 cancer specific methylated genes, were performed on frozen tissue samples from 84 cervical cancer patients and 106 normal cervices. Second, the top 20 discriminating methylation markers were validated by LightCycler® MSP on frozen tissue from 27 cervical cancer patients and 20 normal cervices and ROCs and test characteristics were assessed. Three new methylation markers were identified (JAM3, EPB41L3 and TERT), which were subsequently combined with C13ORF18 in our four‐gene methylation panel. In a third step, our methylation panel detected in cervical scrapings 94% (70/74) of cervical cancers, while in a fourth step 82% (32/39) cervical intraepithelial neoplasia grade 3 or higher (CIN3+) and 65% (44/68) CIN2+ were detected, with 21% positive cases for ≤CIN1 (16/75). Finally, hypothetical scenario analysis showed that primary hr‐HPV testing combined with our four‐gene methylation panel as a triage test resulted in a higher identification of CIN3 and cervical cancers and a higher percentage of correct referrals compared to hr‐HPV testing in combination with conventional cytology. In conclusion, our four‐gene methylation panel might provide an alternative triage test after primary hr‐HPV testing.