Consistency of the S5 DNA methylation classifier in formalin-fixed biopsies versus corresponding exfoliated cells for the detection of pre-cancerous cervical lesions

Triage performance of DNA methylation for women with high-risk human papillomavirus infection

OBJECTIVE

DNA methylation is a promising biomarker for cervical cancer screening. This study aimed to validate the triage performance of cytological DNA methylation for detecting cervical intraepithelial neoplasia of grade 3 or worse (CIN3+) in women with high-risk human papillomavirus (hrHPV) infection from a large prospective cohort undergoing opportunistic screening in China (METHY3).

METHODS

The triage performance for detecting CIN3+ lesions was compared between HPV16/18 genotyping, a liquid-based cytology (LBC) test, and the PAX1 and JAM3 methylation (PAX1m/JAM3m) test according to cervical pathologic outcomes. Among the 4394 women infected with hrHPV, 1105 had definitive cervical histological findings that were analyzed.

RESULTS

For detecting CIN3+, the specificity of HPV16/18(+), the LBC result of ≥atypical squamous cells of undetermined significance (ASCUS), and PAX1m/JAM3m(+) was 66.4%, 23.9%, and 89.6%, respectively, with odds ratios of 4.24 (95% confidence interval [CI], 2.85-6.40), 4.44 (2.27-10.1), and 18.5 (12.1-28.7) (P < .001), respectively. PAX1m/JAM3m(+) had the highest area under the receiver operating characteristic curve (0.790, 95% CI, 0.747-0.832) in the whole cohort and in women of various ages. PAX1m/JAM3m (+) was detected in all patients with cancer (n = 28). Compared with HPV16/18 genotyping and the LBC test, PAX1m/JAM3m testing reduced referrals to colposcopy by 20.64 percentage points and 61.18 percentage points, respectively.

CONCLUSIONS

PAX1 m /JAM3 m testing is highly specific for detecting CIN3+. As a triage biomarker, it is superior to HPV 16/18 genotyping and LBC testing for women with hrHPV infection.

A novel methylation-detection panel for HPV associated high-grade squamous intraepithelial lesion and cervical cancer screening

Cervical cancer (CC) was considered to be the most common gynaecological cancer, with an estimated 342,000 deaths worldwide each year, as the majority of patients were diagnosed at an advanced stage of the disease. The purpose of this study was to evaluate the predictive value of multi-locus methylation assay for the early detection of CC. The cervical exfoliated cell samples from 492 HPV-positive females with cervical lesions were collected and subjected to methylation detection of gene FAM19A4, EPB41L3 and PAX1 after bisulfite conversion. The levels of gene methylation in patients with different severity of cervical lesions were evaluated and compared. The receiver-operating characteristic (ROC) curve was established and efficacy indexes such as sensitivity, specificity and area under the curve (AUC) were calculated to assess the diagnostic value of DNA methylation detection at multiple gene loci for CC. The methylation levels of FAM19A4, EPB41L3 and PAX1 were significantly increased with the grade of cervical squamous intraepithelial lesions. The sensitivities of FAM19A4, EPB41L3 and PAX1 alone for high-grade squamous intraepithelial lesion (HSIL) and CC diagnosis were 84.6%, 86.3% and 88.0%, respectively; when three markers were combined by a logistic regression model, the sensitivity was 88.0%, with a high specificity of 97.7% and AUC of 0.957 (95% CI 0.937-0.977). Methylation status of FAM19A4, EPB41L3 and PAX1 were highly specific and effective for monitoring the progression of cervical lesions and the tri-gene methylation assay could be used as a triage tool for CC early screening.

Cytological DNA methylation for cervical cancer screening: a validation set

Background

In a previous training set with a case-controlled design, cutoff values for host EPB41L3 and JAM3 gene methylation were obtained for the detection of cervical intraepithelial neoplasia (CIN) 2 or more severe lesions (CIN2+). This validation trial was conducted to evaluate the role of DNA methylation in screening for CIN2+ by cervical cytology among unselected participants.

Methods

From June 1, 2019, to September 1, 2019, in our study center, we collected liquid-based samples from cervical swabs for methylation assays and hrHPV testing in eligible patients. The primary endpoint was the diagnostic accuracy of DNA methylation and hrHPV genotyping for CIN2+ according to confirmed histology results.

Results

Among 307 participants, compared with hrHPV testing, the methylation assay for CIN2+ had lower sensitivity (68.7% versus 86.1%, p=0.002) but higher specificity (96.7% versus 0.696, p<0.001). The methylation assay also had favorable sensitivity and specificity in patients with negative hrHPV testing (56.3% and 96.9%) and in patients with cervical adenocarcinoma (73.7% and 92.7%). DNA methylation had higher specificity than the hrHPV assay (100.0% versus 44.4%, p<0.001) for identifying residual CIN2+ in patients without residual lesions. Positive cervical DNA methylation was associated with a diagnostic probability of endometrial carcinoma (odds ratio 15.5 [95% confidence interval 4.1-58.6]) but not of ovarian epithelial carcinoma (1.4 [0.3-6.5]).

Conclusions

The host EPB41L3 and JAM3 gene methylation assay in cervical cytology had favorable diagnostic accuracy for CIN2+ and was highly specific for residual CIN2+ lesions The methylation assay is a promising triage tool in hrHPV+ women, or even an independent tool for cervical cancer screening. The methylation status in cervical cytology could also serve as a prognostic biomarker. Its role in detecting endometrial carcinomas is worthy of further exploration.

The Role of the IGF2 Methylation Score in Diagnosing Adrenocortical Tumors with Unclear Malignant Potential-Feasibility of Formalin-Fixed Paraffin-Embedded Tissue

The differentiation between benign and malignant adrenocortical tumors based on pathological assessment can be difficult. We present a series of 17 patients with unclear malignant tumors, of whom six had recurrent or metastatic disease. The assessment of the methylation pattern of insulin-like growth factor 2 (IGF2) regulatory regions in fresh frozen material has shown to be valuable in determining the malignancy of adrenocortical tumors, although this has not been elaborately tested in unclear malignant tumors. Since fresh frozen tissue was only available in six of the patients, we determined the feasibility of using formalin-fixed paraffin-embedded (FFPE) tissue for this method. We isolated DNA from FFPE tissue and matched the fresh frozen tissue of three patients with adrenocortical carcinoma. Methylation patterns of IGF2 regulatory regions were determined by pyrosequencing using different amounts of bisulfite-converted DNA (5 ng, 20 ng, 40 ng). Compared to fresh frozen tissue, FFPE tissue had a higher failure rate (fresh frozen 0%; FFPE 18.5%) and poor-to-moderate replicability (fresh frozen rho = 0.89-0.99, median variation 1.6%; FFPE rho = -0.09-0.85, median variation 7.7%). There was only a poor-to-moderate correlation between results from fresh frozen and FFPE tissue (rho = -0.28-0.70, median variation 13.2%). In conclusion, FFPE tissue is not suitable for determining the IGF2 methylation score in patients with an unclear malignant adrenocortical tumor using the currently used method. We, therefore, recommend fresh frozen storage of resection material for diagnostic and biobank purposes.

HPV Infection Leaves a DNA Methylation Signature in Oropharyngeal Cancer Affecting Both Coding Genes and Transposable Elements

HPV oncoproteins can modulate DNMT1 expression and activity, and previous studies have reported both gene-specific and global DNA methylation alterations according to HPV status in head and neck cancer. However, validation of these findings and a more detailed analysis of the transposable elements (TEs) are still missing. Here we performed pyrosequencing to evaluate a 5-CpG methylation signature and Line1 methylation in an oropharyngeal squamous cell carcinoma (OPSCC) cohort. We further evaluated the methylation levels of the TEs, their correlation with gene expression and their impact on overall survival (OS) using the TCGA cohort. In our dataset, the 5-CpG signature distinguished HPV-positive and HPV-negative OPSCC with 66.67% sensitivity and 84.33% specificity. Line1 methylation levels were higher in HPV-positive cases. In the TCGA cohort, Line1, Alu and long terminal repeats (LTRs) showed hypermethylation in a frequency of 60.5%, 58.9% and 92.3%, respectively. ZNF541 and CCNL1 higher expression was observed in HPV-positive OPSCC, correlated with lower methylation levels of promoter-associated Alu and LTR, respectively, and independently associated with better OS. Based on our findings, we may conclude that a 5-CpG methylation signature can discriminate OPSCC according to HPV status with high accuracy and TEs are differentially methylated and may regulate gene expression in HPV-positive OPSCC.