Discovery and validation of methylation markers for endometrial cancer

GGTLC1 knockdown inhibits the progression of endometrial cancer by regulating the TGF-β/Smad signaling pathway

Purpose

Endometrial cancer (EC) poses a serious risk to females worldwide; thus, a deep understanding of EC is urgently required. The role and mechanisms of gamma-glutamyltransferase light chain 1 (GGTLC1) in EC remain obscure. This study aims to elucidate the function and mechanisms underlying GGTLC1's involvement in EC.

Methods

Bioinformatic tools and databases were used to analyze GGTLC1 and its associated gene expression in EC tissues. Functional enrichment explorations and immune infiltration analyses were conducted, together with investigation into the methylation status of GGTLC1. Western blotting and Quantitative real-time PCR quantified expression levels. Additional experimental methodologies elucidated the role of GGTLC1 in EC progression. Transcriptome sequencing identified potential regulatory pathways for GGTLC1, and tumor growth was evaluated in vivo using HEC-1A cells in nude mice.

Results

GGTLC1 was upregulated and negatively correlated with immune cell infiltration and DNA methylation in EC. Cell migration and proliferation were reduced following GGTLC1 knockdown, together with arrest at the G0/G1 phase and an upsurge in apoptosis. Compared to the knockdown group, TGF-β/Smad signaling pathway was up-regulated in the negative control group of EC cells by transcriptome analysis. The levels of TGF-β, pSmad2, and pSmad3 followed the same decreasing trend, whereas Smad3 and Smad2 protein levels remained unchanged.

Conclusion

Knockdown of GGTLC1 attenuates EC development through the TGF-β/Smad pathway, positioning GGTLC1 as a promising target for EC treatment.

A new methodology to reveal potential nucleic acid modifications associated with the risk of endometrial cancer through dispersive solid-phase extraction coupled with UHPLC-QE-Orbitrap-MS/MS and HPLC-UV

Nucleic acid modifications have attracted increasing attention in recent years since they have been found to be related to a number of diseases including cancer. Previous studies have shown that the early development of endometrial cancer (EC) is often accompanied by changes in methylation levels of related genes, and the expression of related proteins that regulate reactive oxygen species (ROS) shows significant differences in EC cells and tissues. However, it has not been reported whether nucleic acid modifications related to methylation or ROS can serve as biomarkers for EC. Accurate quantification of these nucleic acid modifications still has challenges because their amounts in urine are very low and the interferences in urine are complicated. In this study, a novel dispersive solid-phase extraction (DSPE) method based on chitosan-carbon nanotube-Al2O3 (CS-CNT-Al2O3) has been established for the analysis of 5-hydroxymethyluracil (5 mU), 5-methyl-2'-deoxycytidine (5-mdC), 5-hydroxymethyl-2'-deoxycytidine (5-hmdC), 5-formyl-2'-deoxycytidine (5-fdC), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in EC patient urine samples coupled with UHPLC-QE-Orbitrap-MS/MS and HPLC-UV. Firstly, the synthesis of the CS-CNT-Al2O3 nanocomposite was conducted by a sono-coprecipitation method and was characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and Fourier transform infrared (FTIR). Under the optimal extraction conditions of DSPE, we successfully quantified 5 mU, 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG in urine samples from 37 EC patients and 39 healthy controls. The results showed that there were significant differences in the levels of 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG in EC patients compared to the healthy control group. The receiver operator characteristic (ROC) curve analysis was carried out to evaluate the potential of 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG to distinguish EC patients from healthy volunteers. The area under the curve (AUC) for 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG was 0.7412, 0.667, 0.8438, and 0.7981, respectively. It indicated that 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG had certain potential in distinguishing between EC patients and healthy volunteers and they could act as potential non-invasive biomarkers for early diagnosis of EC. Moreover, the present study would stimulate investigations of the effects of nucleic acid modifications on the initiation and progression of EC.

Performance of the WID-qEC test versus sonography to detect uterine cancers in women with abnormal uterine bleeding (EPI-SURE): a prospective, consecutive observational cohort study in the UK

BACKGROUND

To detect uterine cancer, simpler and more specific index tests are needed to triage women with abnormal uterine bleeding to a reference histology test. We aimed to compare the performance of conventional index imaging tests with the novel WID-qEC DNA methylation test in terms of detecting the presence or absence of uterine cancers in women with abnormal uterine bleeding.

METHODS

EPI-SURE was a prospective, observational study that invited all women aged 45 years and older with abnormal uterine bleeding attending a tertiary gynaecological diagnostic referral centre at University College London Hospital (London, UK) to participate. Women meeting these inclusion criteria who consented to participate were included. Pregnant women and those with previous hysterectomy were excluded. A cervicovaginal sample for the WID-qEC test was obtained before standard assessment using index imaging tests (ie, ultrasound) and, where applicable, reference histology (ie, biopsy, hysteroscopy, or both) was performed. Technicians performing the WID-qEC test were masked to the final clinical outcome. The result of the WID-qEC test is defined as the sum of the percentage of fully methylated reference (ΣPMR) of the ZSCAN12 and GYPC regions. Patients were followed until diagnostic resolution or until June 12, 2023. The primary outcome was to assess the real-world performance of the WID-qEC test in comparison with ultrasound with regard to the area under the receiver-operating-characteristic curve (AUC), sensitivity, specificity, and positive and negative predictive values. EPI-SURE is registered with ISRCTN (16815568).

FINDINGS

From June 1, 2022, to Nov 24, 2022, 474 women were deemed eligible to participate. 74 did not accept the invitation to participate, and one woman withdrew after providing consent. 399 women were included in the primary analysis cohort. Based on 603 index imaging tests, 186 (47%) women were recommended for a reference histology test (ie, biopsy, hysteroscopy, or both). 12 women were diagnosed with cancer, 375 were not diagnosed with cancer, and 12 had inconclusive clinical outcomes and were considered study dropouts. 198 reference histology test procedures detected nine cases of cancer and missed two; one further cancer was directly diagnosed at hysterectomy without a previous reference test. The AUC for detection of uterine cancer based on endometrial thickness in mm was 87·2% (95% CI 71·1-100·0) versus 94·3% (84·7-100·0) based on WID-qEC (p=0·48). Endometrial thickness assessment on ultrasound scan was possible in 379 (95%) of the 399 women and a prespecified cut-off of 4·5 mm or more showed a sensitivity of 90·9% (95% CI 62·3-98·4), a specificity of 79·1% (74·5-82·9), a positive predictive value of 11·8% (6·5-20·3), and a negative predictive value of 99·6% (98·0-99·9). The WID-qEC test was possible in 390 (98%) of the 399 patients with a sensitivity of 90·9% (95% CI 62·3-98·4), a specificity of 92·1% (88·9-94·4), a positive predictive value of 25·6% (14·6-41·1), and a negative predictive value of 99·7% (98·3-99·9), when the prespecified threshold of 0·03 ΣPMR or more was applied. When a higher threshold (≥0·3 ΣPMR) was applied the specificity increased to 97·3% (95% CI 95·1-98·5) without a change in sensitivity.

INTERPRETATION

The WID-qEC test delivers fast results and shows improved performance compared with a combination of imaging index tests. Triage of women with abnormal uterine bleeding using the WID-qEC test could reduce the number of women requiring histological assessments for identification of potential malignancy and specifically reduce the false positive rate.

FUNDING

The Eve Appeal, Land Tirol, and the European Research Council under the European Union's Horizon 2020 Research and Innovation Programme.

Hypermethylated CDO1 and CELF4 in cytological specimens as triage strategy biomarkers in endometrial malignant lesions

Objective

Developing a non-invasive and reliable triage test for endometrial malignant lesions is an important goal, as it could help to reduce the number of invasive diagnostic procedures required and improve patient survival. We aimed to estimate the diagnostic value of DNA methylation levels in cervical cytological samples of endometrial cancer (EC) and endometrial atypical hyperplasia (AH).

Methods

A total of 607 women who had indications for endometrial biopsy in the Department of Obstetrics and Gynecology of Cangzhou Central Hospital from October 2022 to April 2023 were enrolled in this study. The cervical exfoliated cells were collected for gene methylation before endometrial biopsy. Clinical information, tumor biomarkers, and endometrial thickness (ET) of transvaginal ultrasonography (TVS) were also collected. With endometrial histopathology as the gold standard, multivariate unconditional logistic regression was applied to analyze the risk factors of endometrial malignant lesions. The role of cysteine dioxygenase type 1 (CDO1) and CUGBP Elav-like family member 4 (CELF4) gene methylation as a triage strategy biomarker in endometrial malignant lesions was specifically explored.

Results

Multivariate logistic regression analysis showed that premenopausal ET ≥ 11 mm or postmenopausal ET ≥ 5 mm, CDO1 ΔCt ≤ 8.4, or CELF4 ΔCt ≤ 8.8 were the risk factors for AH and EC, with odds ratios (ORs) (95%CI) of 5.03 (1.83-13.82) and 6.92 (1.10-43.44), respectively (p-values < 0.05). The sensitivity and specificity of CDO1/CELF4 dual-gene methylation assay for AH and EC reached 84.9% (95%CI: 75.3%-94.5%) and 86.6% (95%CI: 83.8%-89.5%), respectively. ET combined with DNA methylation detection further improved the specificity to (94.9%, 95%CI: 93.1%-96.8%).

Conclusion

The accuracy of cervical cytology DNA methylation is superior to that of other clinical indicators in the non-invasive examination of endometrial malignant lesions. DNA methylation combined with TVS can further improve the specificity and is a promising biomarker triage strategy in women with suspected endometrial lesions.

Detection of endometrial cancer using tampon-based collection and methylated DNA markers

OBJECTIVE

Alterations in DNA methylation are early events in endometrial cancer (EC) development and may have utility in EC detection via tampon-collected vaginal fluid.

METHODS

For discovery, DNA from frozen EC, benign endometrium (BE), and benign cervicovaginal (BCV) tissues underwent reduced representation bisulfite sequencing (RRBS) to identify differentially methylated regions (DMRs). Candidate DMRs were selected based on receiver operating characteristic (ROC) discrimination, methylation level fold-change between cancers and controls, and absence of background CpG methylation. Methylated DNA marker (MDM) validation was performed using qMSP on DNA from independent EC and BE FFPE tissue sets. Women ≥45 years of age with abnormal uterine bleeding (AUB) or postmenopausal bleeding (PMB) or any age with biopsy-proven EC self-collected vaginal fluid using a tampon prior to clinically indicated endometrial sampling or hysterectomy. Vaginal fluid DNA was assayed by qMSP for EC-associated MDMs. Random forest modeling analysis was performed to generate predictive probability of underlying disease; results were 500-fold in-silico cross-validated.

RESULTS

Thirty-three candidate MDMs met performance criteria in tissue. For the tampon pilot, 100 EC cases were frequency matched by menopausal status and tampon collection date to 92 BE controls. A 28-MDM panel highly discriminated between EC and BE (96% (95%CI 89-99%) specificity; 76% (66-84%) sensitivity (AUC 0.88). In PBS/EDTA tampon buffer, the panel yielded 96% (95% CI 87-99%) specificity and 82% (70-91%) sensitivity (AUC 0.91).

CONCLUSION

Next generation methylome sequencing, stringent filtering criteria, and independent validation yielded excellent candidate MDMs for EC. EC-associated MDMs performed with promisingly high sensitivity and specificity in tampon-collected vaginal fluid; PBS-based tampon buffer with added EDTA improved sensitivity. Larger tampon-based EC MDM testing studies are warranted.

Results of Endometrial Sampling in a Tertiary Hospital

AIM

This study aims to investigate the results of endometrial sampling in a tertiary hospital according to age and symptoms.

MATERIALS AND METHODS

A total of 505 patients who underwent endometrial sampling due to various reasons in our tertiary hospital in the last six months were included in our study, and the pathological results of endometrial sampling were analyzed retrospectively.

RESULTS

The mean age of 505 patients was 45.03 + 7.40 (19-74) years, and 91.5% of the indications were premenopausal abnormal uterine bleeding and 8.5% were postmenopausal bleeding. The most common pathological result of all age groups was proliferative endometrium (37.6%), and the least was the endometrial intraepithelial neoplasia (0.2%). In 9.3% of patients, the result was insufficient material. Of the patients, 88.7% had no additional organic pathology. A total of 30 (5.9%) patients have undergone surgery after endometrial sampling.

CONCLUSION

It should be kept in mind that despite the pathological result may be insufficient rarely, endometrial sampling should be performed as the first choice in abnormal uterine bleeding.

Accuracy of cytological examination of Tao brush endometrial sampling in diagnosing endometrial premalignancy and malignancy

Although Tao brush has become one of the most studied and used endometrial cytological samplers, concerns remain about the adequacy of the cytological sample compared with definitive histology. We aimed to assess accuracy of cytological examination from Tao brush sampling in diagnosing endometrial premalignancy and malignancy through a systematic review and meta-analysis. Seven electronic databases were searched from January 2000 to July 2021 for all studies which allowed assessment of accuracy of Tao brush in diagnosing endometrial premalignancy and malignancy. We calculated sensitivity, specificity, positive and negative likelihood ratios (LR+ and LR-), diagnostic odds ratio (DOR) and area under the curve (AUC) on summary receiver operating characteristic (SROC) curve. Five studies with 774 patients were included. In diagnosing endometrial premalignancy and malignancy, cytological examination from Tao brush endometrial sampling showed pooled sensitivity of 0.95 (95% CI, 0.90-0.98), specificity of 0.92 (95% CI, 0.90-0.94), LR+ of 12.73 (95% CI, 3.94-41.18), LR- of 0.09 (95% CI, 0.05-0.18), DOR of 184.84 (95% CI, 24.37-1401.79), AUC of 0.9757 (standard error: 0.013). In conclusion, cytological examination from Tao brush seems to have a high diagnostic accuracy and might be proposed as both screening and diagnostic tool. However, further studies are necessary to confirm these findings.

A Simple Cervicovaginal Epigenetic Test for Screening and Rapid Triage of Women With Suspected Endometrial Cancer: Validation in Several Cohort and Case/Control Sets

PURPOSE

Endometrial cancer (EC) incidence has been rising over the past 10 years. Delays in diagnosis reduce survival and necessitate more aggressive treatment. We aimed to develop and validate a simple, noninvasive, and reliable triage test for EC to reduce the number of invasive diagnostic procedures and improve patient survival.

METHODS

We developed a test to screen and triage women with suspected EC using 726 cervical smear samples from women with and without EC, and validated the test in 562 cervicovaginal samples using three different collection methods (cervical smear: n = 248; vaginal swab: n = 63; and self-collection: n = 251) and four different settings (case/control: n = 388; cohort of women presenting with postmenopausal bleeding: n = 63; a cohort of high-risk women with Lynch syndrome: n = 25; and a nested case/control setting from a screening cohort and samples taken up to 3 years before EC diagnosis: n = 86).

RESULTS

We describe the Women's cancer risk IDentification - quantitative polymerase chain reaction test for Endometrial Cancer (WID-qEC), a three-marker test that evaluates DNA methylation in gene regions of GYPC and ZSCAN12. In cervical, self-collected, and vaginal swab samples derived from symptomatic patients, it detected EC with sensitivities of 97.2% (95% CI, 90.2 to 99.7), 90.1% (83.6 to 94.6), and 100% (63.1 to 100), respectively, and specificities of 75.8% (63.6 to 85.5), 86.7% (79.3 to 92.2), and 89.1% (77.8 to 95.9), respectively. The WID-qEC identified 90.9% (95% CI, 70.8 to 98.9) of EC cases in samples predating diagnosis up to 1 year. Test performance was similar across menopausal status, age, stage, grade, ethnicity, and histology.

CONCLUSION

The WID-qEC is a noninvasive reliable test for triage of women with symptoms suggestive of ECs. Because of the potential for self-collection, it could improve early diagnosis and reduce the reliance for in-person visits.

Endometrial Cancer Detection Using a Cervical DNA Methylation Assay (MPap) in Women with Abnormal Uterine Bleeding: A Multicenter Hospital-Based Validation Study

Simple Summary

We conducted a multicenter validation study using a methylation assay, named MPap, to detect EC. MPap is used to identify the DNA methylation status of two genes, BHLHE22 and CDO1, from cervical scrapings, and the results are combined with age and body mass index. In two stages of validation, the sensitivity, specificity, and positive and negative predictive values were 92.5~92.9%, 71.5~73.8%, 39.8~40.2%, and 98.0~98.1%, respectively. The MPap test is a feasible alternative tool that provides physicians with a reference for assessing susceptibility to endometrial cancer.

Abstract

Background: We describe a DNA methylation assay, named MPap test, using cervical scraping as an alternative technique for endometrial cancer detection. Methods: A multicenter hospital-based, two-stage validation study was conducted to validate the cancer detection performance of the MPap test. The MPap value was determined from the DNA methylation status of two genes (BHLHE22, CDO1) and combined with two other clinical variables (age, BMI). The cutoff threshold of the MPap value was established in stage 1 and validated in stage 2. A total of 592 women with abnormal uterine bleeding were enrolled from five medical centers throughout Taiwan. Results: In stage 1, the sensitivity, specificity, and positive and negative predictive values of the MPap test for detecting endometrial cancer were 92.9%, 71.5%, 39.8%, and 98.0%, respectively. These values were validated in stage 2, being 92.5%, 73.8%, 40.2%, and 98.1%. Moreover, MPap outperformed transvaginal ultrasound in sensitivity and negative predictive values for detecting endometrial cancer. When we applied the algorithm for triage of endometrial cancer detection by MPap in the Taiwan National Health Insurance dataset, we found that it may reduce invasive procedures by 69~73%. Conclusions: MPap may provide a feasible alternative for endometrial cancer detection and can be considered as a triage test to reduce unnecessary invasive procedures.

Hypermethylated CDO1 and ZNF454 in Cytological Specimens as Screening Biomarkers for Endometrial Cancer

We aimed to estimate the diagnostic value of DNA methylation levels in cytological samples of endometrial cancer (EC) and atypical hyperplasia (AH). Two hypermethylated genes, namely, cysteine dioxygenase type 1 (CDO1) and zinc finger protein 454 (ZNF454), in patients with EC were identified from The Cancer Genome Atlas database. In 103 endometrial histological specimens (the training set), the methylation levels of candidate genes were verified by quantitative methylation-specific polymerase chain reaction (qMSP). The methylation levels of another 120 cytological specimens (the testing set) were evaluated. Sensitivity (Se), specificity (Sp), accuracy, and area under the curve (AUC) were determined, with diagnosis verified by histopathological results. CDO1 and ZNF454 verified hypermethylation in histological specimens of patients with EC and AH compared with those with benign and normal endometrium (P < 0.001). In cytological specimens, hypermethylated CDO1 showed 86.36% Se and 90.79% Sp with the cutoff value of 6.0 to distinguish between malignant and benign groups; ZNF454 showed 79.55% Se and 93.42% Sp with the cutoff value of 7.1. When the two genes were combined, Se increased to 90.91% and Sp was 86.84%. AUC reached 0.931 (95% CI: 0.885–0.976). The diagnostic accuracy with cytology had no significant difference with endometrial tissue (P = 0.847 for CDO1, P = 0.108 for ZNF454, and P = 0.665 for their combination). Hypermethylated CDO1 and ZNF454 in endometrial cytology showed high Se, Sp, and AUC to detect EC and AH. Methylation analysis of endometrial cytology is promising biomarker for the screening of EC and AH.

Developing a novel DNA methylation risk score for survival and identification of prognostic gene mutations in endometrial cancer: a study based on TCGA data

Background

Few studies have focused on DNA methylation in endometrial cancer. The aim of our study is identify its role in endometrial cancer prognosis.

Methods

A publicly available dataset was retrieved from The Cancer Genome Atlas. For validation of expression alteration due to methylation, RNA sequencing data were obtained from other independent cohorts. MethSurv was used to search for candidate CpG probes, which were then filtered by least absolute shrinkage and selection operator Cox regression and multivariate Cox regression analyses to identify final set of CpG probes for overall survival. A methylation-based risk model was developed and receiver operating characteristic analysis with area under curve was used for evaluation. Patients were divided into high- and low-risk groups using an optimal cut-off point. Comprehensive bioinformatic analyses were conducted to identify hub genes, key transcription factors, and enriched cancer-related pathways. Kaplan–Meier curve was used for survival analysis.

Results

A 5-CpG signature score was established. Its predictive value for 5-year overall survival was high, with area under curve of 0.828, 0.835 and 0.816 for the training, testing and entire cohorts. cg27487839 and cg12885678 had strong correlation with their gene expression, XKR6 and PTPRN2, and lower PTPRN2 expression was associated with poorer survival in both The Cancer Genome Atlas and the validation datasets. Low-risk group was associated with significantly better survival. Low-risk group harboured more mutations in hub genes and key transcription factors, and mutations in SP1 and MECP2 represented favourable outcome.

Conclusion

We developed a methylation-based prognostic stratification system for endometrial cancer. Low-risk group was associated with better survival and harboured more mutations in the key regulatory genes.

Hypermethylated PCDHGB7 as a Biomarker for Early Detection of Endometrial Cancer in Endometrial Brush Samples and Cervical Scrapings

Endometrial cancer (EC) is one of the most common gynecologic cancers in developed countries. Presently, it is imperative to develop a reliable, noninvasive, or minimally invasive detection method for EC. We explored the possibility of using DNA methylation marker from endometrial brush samples (with a “Tao brush”) and cervical scrapes (with a “Pap brush”) for early detection of EC. We analyzed the methylation data of EC and normal endometrial tissues from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) data sets. An optimized methylation-sensitive restriction enzyme combined with real-time fluorescent quantitative PCR (MSRE-qPCR) was used for methylation detection. Included in the training set were 143 endometrial tissues, 103 Tao, and 109 Pap brush samples. The validation set included 110 Tao and 112 Pap brush samples. PCDHGB7 was significantly hypermethylated in EC compared with normal endometrial tissues in the TCGA and GEO data sets (AUC >0.95), which was verified in clinical samples. In the Pap brush samples, the AUC was 0.86 with 80.65% sensitivity and 82.81% specificity, whereas the Tao brush samples exhibited higher specificity (95.31%). The combination of Tao and Pap brush samples significantly increased the sensitivity to 90.32%. In the validation set, the final model yielded a sensitivity of 98.61%, specificity of 60.53%, positive predictive value of 82.56%, and negative predictive value of 95.83%. These results demonstrate the potential application of the novel methylation marker, hypermethylated PCDHGB7, in cervical scrapings and endometrial brush, which provides a viable, noninvasive, or minimally invasive method for early endometrial cancer detection across different clinical features and histologies to supplement current hysteroscopy diagnosis.

Tao brush endometrial cytology is a sensitive diagnostic tool for cancer and hyperplasia among women presenting to clinic with abnormal uterine bleeding

Background

Abnormal uterine bleeding requires the investigation of the endometrium. Histology is typically used but there remains room for the improvement and use of cytology.

Methods

Women presenting for clinically indicated office endometrial biopsy were prospectively enrolled. Tao endometrial brushing and office endometrial biopsy were performed, and surgical procedure if clinically indicated. Tao brush cytology specimens were blindly reviewed by up to three pathologists, consensus obtained, and scored as: benign, atypical (favor benign), suspicious, positive for malignancy, or non‐diagnostic. Cytology and histology were compared to surgical pathology to determine sensitivity, specificity, positive, and negative predictive values to detect AH (atypical hyperplasia) or EC (endometrial cancer).

Results

Clinical indications of 197 enrolled patients included postmenopausal bleeding (90, 45.7%), abnormal uterine bleeding (94, 47.7%), and abnormal endometrium on ultrasound without bleeding (13, 6.6%). Of the 197 patients, 185 (93.9%) had cytology score consensus and a total of 196 (99.5%) had consensus regarding cytology positivity.

Surgical pathology diagnoses (N = 85) were 13 (15.3%) FIGO grade 1 or 2 EC, 3 (3.5%) AH, and 69 (81.2%) benign endometrium. Sensitivity and specificity to detect EC or AH were 93.7% and 100%, respectively, via endometrial biopsy; 87.5% and 63.8%, respectively, via endometrial cytology when scores of malignancy, suspicious, or atypical were considered positive.

Conclusions

In a high‐risk population, Tao brush endometrial cytology showed high sensitivity to detect AH and EC comparable to biopsy histology when considering scores of malignancy, suspicious, atypical, and non‐diagnostic. Revisiting the potential value of endometrial cytology in the contemporary era of endometrial diagnostic workup is warranted.

A seven-m6A regulator-related CpG site-based prognostic signature for endometrial carcinoma

BACKGROUND

Endometrial carcinoma (EC) has become a common gynecologic malignancy with a high mortality. The m6A regulators have been identified to be closely associated with multiple human cancers including EC. However, the CpG methylation signature related to m6A regulators in EC remains unclear.

METHOD

The methylation profiles of EC patients including cancer samples and adjacent normal samples were obtained from The Cancer Genome Atlas (TCGA) database. The CpG sites in 20 m6A regulators were identified. Univariate Cox regression and LASSO Cox regression analysis were used to screen key CpG sites which were located at m6A regulators and significantly related to the prognosis of EC. The predictive model for EC prognosis was constructed, and multivariate Cox regression analysis was applied to explore whether the risk score derived from the model could function as an independent signature for EC prognosis. Meanwhile, a nomogram model was constructed by combing the independent prognostic signatures for prediction of the long-term survival in EC patients.

RESULTS

A total of 396 CpG sites located at 20 m6A regulators were identified. A specific predictive model for EC prognosis based on 7 optimal CpG sites was constructed, which presented good performance in prognosis prediction of EC patients. Moreover, risk score was determined to be an independent signature both in the training set and validation set. By bringing in three independent prognostic factors (age, risk score, and TNM stage), the nomogram was constructed and could effectively predict the 3- and 5-year survival rates of EC patients.

CONCLUSION

Our study suggested that the CpG sites located at m6A regulators might be considered as potential prognostic signatures for EC patients.

A ten-gene methylation signature as a novel biomarker for improving prediction of prognosis and indicating gene targets in endometrial cancer

Endometrial cancer (EC) is a common female reproductive tumor worldwide. Nonetheless, the pathogenesis of EC still remains ambiguous and associated epigenetic mechanism still to be explored. The goal of this study is to investigate whether gene methylation signature is associated with overall survival (OS) for EC patients. In this study, a 10-gene methylation risk model was built and the OS in high- and low-risk groups was significant different. The area under the ROC curve (AUC) of this model was 0.856 at 5 years survival. The nomogram could accurately predict the OS in EC patients, with concordance index and AUC at 5 year survival reached 0.796 and 0.792, respectively. Furthermore, we verified the nomogram with 24 patients in our center and the Kaplan-Meier survival curve also proved to be significantly different (p < 0.01). WGCNA revealed a key gene group for the model and further bioinformatics analysis indicated 6 genes as the hub genes in the module. Knockdown of MMP12 inhibited the proliferation, invasion and metastasis of EC cells. After all, a methylation signature and a nomogram based on this signature were constructed, and they could both predict survival in patients with EC. Moreover, WGCNA model identified MMP12 as a potential target for the treatment of EC.

New development on hysteroscopy for endometrial cancer diagnosis: state of the art

Endometrial cancer (EC) is the most common gynecologic cancer diagnosed in developed countries and represents the second most frequent gynecologic cancer-related cause of death following ovarian cancer. There are 2 subtypes of EC. Type I tumors (endometrioid adenocarcinoma) representing 85-90% of the cases. They are likely to be low-grade tumors and are thought to have a link to estrogen exposure. Type II tumors represent 10-15% of EC. They are characterized as high-grade carcinomas, with serous or clear cell histology type, and carry poor prognoses. The benefits of hysteroscopy in achieving a targeted endometrial biopsy under direct visualization over blind biopsy techniques are widely accepted. Hysteroscopic endometrial biopsy is performed under direct visualization and is the only technique that allows for the selective biopsy of targeted areas of the endometrium. There is no screening protocol for the early detection of EC. Among the general population, advanced age, obesity, nulliparity and the use of exogenous hormones are known as risk factors for EC. There are additional situations that portend an increased risk of EC that deserve special consideration such as in patients diagnosed with Lynch Syndrome, using tamoxifen, obese, or the young patient with a desire for future fertility. We presented a narrative review of the current role of hysteroscopy for the diagnosis of endometrial cancer.

The underlying molecular mechanism and drugs for treatment in adrenal cortical carcinoma

Purpose: The study aimed to predict and explore the possible clinical value and mechanism of genetic markers in adrenal cortical carcinoma using a bioinformatics analysis method. Methods: The RNA-seqs and miRNAs data were downloaded from TCGA database to identify the differentially expressed genes and differentially expressed miRNAs. The hub-genes were screened by building protein-protein interaction sub-networks with 12 topological analysis methods. We conducted the receiver operating characteristic curve to elevate the diagnostic value of hub-genes in distinguishing the death and alive groups. The survival analysis of hub-genes and key miRNAs were conducted using Kaplan-Meier curves. Furthermore, most significant small molecules were identified as therapeutic candidates for adrenal cortical carcinoma by the CMap analysis. Results: Compared to survival group, we found 475 up-regulated genes and 354 genes and the key pathways leading to the death of different ACC individual patients. Then we used 12 topological analysis methods to found the most possible 22 hub-genes. Among these hub-genes, nine hub-genes (C3, CXCL5, CX3CR1, GRM8, HCAR2, HTR1B, SUCNR1, PTGER3 and SSTR1) could be used to distinguish the death and survival groups for patients. We also revealed that mRNA expressions of 12 genes (C3, CXCL8, CX3CR1, GNAT3, GNGT1, GRM8, HCAR2, HTR1B, HTR1D, PTGER3, SSTR1 and SUCNR1) and four key miRNAs (hsa-mir-330, hsa-mir-489, hsa-mir-508 and hsa-mir-513b) were related to survival. Three most small molecules were identified (H-9, AZ-628 and phensuximide) as potential therapeutic drugs for adrenal cortical carcinoma. Conclusion: The hub-genes expression was significant useful in adrenal cortical carcinoma, provide new diagnostic, prognosis and therapeutic approaches for adrenal cortical carcinoma. Furthermore, we also explore the possible miRNAs involved in regulation of hub-genes.

Non-invasive detection of endometrial cancer by DNA methylation analysis in urine

Background

The incidence of endometrial cancer is rising, and current diagnostics often require invasive biopsy procedures. Urine may offer an alternative sample type, which is easily accessible and allows repetitive self-sampling at home. Here, we set out to investigate the feasibility of endometrial cancer detection in urine using DNA methylation analysis.

Results

Urine samples of endometrial cancer patients (n = 42) and healthy controls (n = 46) were separated into three fractions (full void urine, urine sediment, and urine supernatant) and tested for three DNA methylation markers (GHSR, SST, ZIC1). Strong to very strong correlations (r = 0.77–0.92) were found amongst the different urine fractions. All DNA methylation markers showed increased methylation levels in patients as compared to controls, in all urine fractions. The highest diagnostic potential for endometrial cancer detection in urine was found in full void urine, with area under the receiver operating characteristic curve values ranging from 0.86 to 0.95.

Conclusions

This feasibility study demonstrates, for the first time, that DNA methylation analysis in urine could provide a non-invasive alternative for the detection of endometrial cancer. Further investigation is warranted to validate its clinical usefulness. Potential applications of this diagnostic approach include the screening of asymptomatic women, triaging women with postmenopausal bleeding symptoms, and monitoring women with increased endometrial cancer risk.

DNA methylation markers for endometrial cancer detection in minimally invasive samples: a systematic review

Aim: DNA methylation testing for endometrial cancer detection in minimally invasive specimens is a promising tool to improve screening and diagnostic procedures. Available literature was systematically reviewed to assess the potential of this approach and define methylation markers deserving further development. Methods: A systematic search up to March 31 2020 was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Results: 15 methylation markers with an area under the curve value of ≥ 0.80 for endometrial cancer detection in cytological specimens were selected from nine studies. Conclusion: Detection of methylation markers in cytological samples indicate the feasibility of minimally invasive testing methods, potentially guiding diagnosis and detection of endometrial cancer in high-risk women and in cancer screening programs.

Estrogen-ERα signaling and DNA hypomethylation co-regulate expression of stem cell protein PIWIL1 in ERα-positive endometrial cancer cells

Background

We previously identified PIWIL1 as an oncogene involved in endometrial carcinogenesis. However, the mechanism of Piwil1 mediated regulation of tumorigenesis remains poorly understood.

Methods

The expression levels of target genes in endometrial cancer cells were detected by quantitative reverse transcription-PCR (RT-qPCR) and western blotting. Up- or down-regulation of ERα or PIWIL1 was achieved by transient transfection with expressing plasmids or short hairpin RNA (shRNA). Dual-luciferase reporter assays and chromatin immunoprecipitation (ChIP) were used to demonstrate the ERα bound to the half estrogen response element (half-ERE) located in PIWIL1 promoter. The expression of PIWIL1 and ERα in endometrial carcinoma tissues were investigated using immunohistochemistry and RT-qPCR. The proliferation ability of cancer cells were evaluated by MTT. Methylation status of the PIWIL1 promoter was detected by bisulfite sequencing PCR (BSP).

Results

In the present study, we found that PIWIL1 mediated E₂-stimulated cancer cell proliferation. In ERα-positive endometrial cancer cells, we demonstrated that estrogen-ERα signaling significantly up-regulated the expression of PIWIL1, which was mediated by binding of the ERα onto the PIWIL1 promoter. Furthermore, we found that a half-ERE in the PIWIL1 promoter was essential for ERα binding. The PIWIL1 promoter was hypomethylated in ERα-positive endometrial cancer cells. Treatment with 5-aza-deoxycytidine (5-aza-dC) could up-regulate PIWIL1 expression.

Conclusions

These findings uncover a novel molecular mechanism by which estrogen-ERα signaling and DNA hypomethylation co-regulate PIWIL1 expression. These findings provide novel insights into the hormonal regulation of PIWIL1 in endometrial cancer and the PIWIL1’s role in estrogen-stimulated endometrial carcinogenesis.

Expression of Stromal Progesterone Receptor and Differential Methylation Patterns in the Endometrium May Correlate with Response to Progesterone Therapy in Endometrial Complex Atypical Hyperplasia

Progesterone therapy is a viable treatment for complex atypical hyperplasia (CAH) and endometrial adenocarcinoma, though reliable molecular determinants of response are not available. To explore if analysis of pre-therapy endometrial biopsies could yield biomarkers of response to progesterone, patients with CAH or adenocarcinoma undergoing treatment with progestins were included in this cross-sectional study. Immunohistochemistry for progesterone receptor (PR) was performed. Manual PR expression scores (PRES) were first calculated for biopsies by counting PR-positive nuclei in 12 sensitive vs 9 resistant samples. Significant differences in manual PRES were detected in the stroma (p < 0.01) and total endometrium (p < 0.01) for sensitive vs resistant patients. Manual PRES in the stroma had the highest accuracy in segregating sensitive vs resistant patients (96%). Differences in epithelial PRES were not significant. To validate these findings, a correlation between manual PRES and visual PRES was performed in the 21 patients. An additional 11 patients were analyzed to test if visual PRES would be predictive of response to progesterone. Visual PRES in epithelia and stroma in the 32 specimens was calculated. Significant differences in visual PRES were detected in the stroma for sensitive vs resistant samples (p < 0.01), while differences in epithelial and total endometrium were not significant. Whole genome bisulfite sequencing was performed on DNA isolated using pre-therapy biopsies from 6 sensitive and 6 resistant patients in this cohort. Differentially methylated regions were identified in the stroma and epithelium when evaluating sensitive vs resistant samples. Pathways involved in cell adhesion demonstrated the greatest difference in methylation in these samples.

Analysis of DNA methylation in endometrial biopsies to predict risk of endometrial cancer

OBJECTIVE

To determine whether analysis of methylated DNA in benign endometrial biopsy (EB) specimens is associated with risk of endometrial cancer (EC).

METHODS

We identified 23 women with EBs performed at Mayo Clinic diagnosed as normal (n = 14) or hyperplasia (n = 9) and who later developed endometrial cancer after a median interval of 1 year. Cases were matched 1:1 with patients with benign EBs who did not develop EC (controls) by histology of benign EB (normal endometrium vs. endometrial hyperplasia without atypia), date of EB, age at EB, and length of post-biopsy follow-up. DNA extracted from formalin-fixed paraffin-embedded tissues underwent pyrosequencing to determine percent methylation of promoter region CpGs at 26 loci in 4 genes (ADCYAP1, HAND2, MME, RASSF1A) previously reported as methylated in EC.

RESULTS

After pathologic review, 23 matched pairs of cases and controls were identified (14 normal, 9 hyperplasia without atypia per group). Among cases, median time from benign EB to EC was 1 year (range 2 days - 9.2 years). We evaluated 26 CpG sites within 4 genes and found a consistent trend of increasing percentage of methylation from control to case to EC for all CpGs. At the gene-level, mean methylation events of ADCYAP1 and HAND2 in cases were significantly higher than control (p = 0.015 and p = 0.021, respectively). Though the other genes did not reach statistical significance, we observed an increased methylation trend among all genes. Area-under-curve (AUC) calculations (predicting future development of EC in the setting of benign EB) for ADCYAP1 and HAND2 were 0.71 (95% CI 0.55-0.88) and 0.83 (95% CI 0.64-1, respectively).

CONCLUSIONS

This proof-of-principle study provides evidence that specific methylation patterns in benign EB correlate with future development of EC.

Combined genetic mutations and DNA-methylated genes as biomarkers for endometrial cancer detection from cervical scrapings

Background

Endometrial cancer is a common gynecologic cancer. Noninvasive molecular biomarkers for triage of high-risk patients for invasive procedures are needed. Based on the success of cytological Pap smear screening, cervical scrapings are a good source of DNA for molecular testing. In addition to genetic lesions, DNA methylation is a promising biomarker. We assessed the usefulness of combining genetic and epigenetic biomarkers from cervical scrapings to detect endometrial carcinomas.

Methods

We performed a retrospective case–control study of 96 consecutive cervical scrapings from patients with abnormal uterine bleeding who underwent surgery for diagnostic evaluation. Thirty and 16 cases were diagnosed with type I and type II endometrial cancers, respectively. The remaining non-cancer cases included normal endometrium (n = 12), benign uterine lesions (n = 20), and endometrial hyperplasia (n = 18). Quantitative methylation-specific PCR and mass spectrometry were used for DNA methylation and genetic mutation analysis. Logistic regression was used to evaluate the clinical performance of these candidate biomarkers.

Results

We tested the effectiveness of the methylation status of four genes (BHLHE22, CDO1, TBX5, and HAND2) in endometrial cancer detection. The area under the receiver operating characteristic curves ranged from 0.703 to 0.878, and panels of hypermethylated BHLHE22/CDO1/HAND2 (87.0% sensitivity and 86.0% specificity) and BHLHE22/CDO1/TBX5 (89.1% sensitivity and 80.0% specificity) showed significant differences and could distinguish benign from malignant endometrial lesions. The sensitivity and specificity in endometrial cancer detection for BHLHE22/CDO1 were 84.8% and 88.0%, respectively. Both type I and II endometrial carcinomas could be detected using a BHLHE22/CDO1-based methylation profile, suggesting that they may have common epigenomes. Moreover, PTEN and TP53 mutations were found in 63.3% of type I and 93.6% of type II endometrial cancers. Unexpectedly, PTEN and TP53 mutations were commonly found in cervical scrapings of the normal endometrium (25% and 33.3%, respectively) and in cases with benign uterine lesions (10% and 50%, respectively). Finally, combinations of any one mutation of PTEN and TP53 mutations had a sensitivity of 91.3%, but a specificity of only 42.0%.

Conclusions

Adding PTEN/TP53 mutation testing to BHLHE22/CDO1-based methylation testing did not improve the detection of endometrial cancer.

A prospective clinical cohort study of women at increased risk for endometrial cancer

OBJECTIVE

To evaluate endometrial cancer (EC) risk assessment and early detection strategies in high-risk populations, we designed a large, prospective cohort study of women undergoing endometrial evaluation to assess risk factors and collect novel biospecimens for future testing of emerging EC biomarkers. Here we report on the baseline findings of this study.

METHODS

Women aged ≥45 years were enrolled at the Mayo Clinic from February 2013-June 2018. Risk factors included age, body mass index (BMI), smoking, oral contraceptive and hormone therapy use, and parity. We collected vaginal tampons, endometrial biopsies, and Tao brush samples. We estimated mutually-adjusted odds ratios (OR) and 95% confidence intervals (CI) using multinomial logistic regression; outcomes included EC, atypical hyperplasia, hyperplasia without atypia, disordered proliferative endometrium, and polyps, versus normal endometrium.

RESULTS

Subjects included 1205 women with a mean age of 55 years; 55% were postmenopausal, and 90% had abnormal uterine bleeding. The prevalence of EC was 4.1% (n = 49), predominantly diagnosed in postmenopausal women (85.7%). Tampons and Tao brushings were obtained from 99% and 68% of women, respectively. Age (OR 1.14, 95% CI 1.1-1.2) and BMI (OR 1.39, 95% CI 1.1-1.7) were positively associated with EC; atypical hyperplasia (OR 1.07, 95% CI 1.0-1.1; OR 2.00, 95% CI 1.5-2.6, respectively), and polyps (OR 1.06, 95% CI 1.0-1.1; OR 1.17, 95% CI 1.0-1.3, respectively); hormone therapy use and smoking were inversely associated with EC (OR 0.42, 95%, 0.2-0.9; OR 0.43, 95% CI, 0.2-0.9, respectively). Parity and past oral contraception use were not associated with EC.

CONCLUSIONS

Well-established EC risk factors may have less discriminatory accuracy in high-risk populations. Future analyses will integrate risk factor assessment with biomarker testing for EC detection.

Proteomic Biomarkers for the Detection of Endometrial Cancer

Endometrial cancer is the leading gynaecological malignancy in the western world and its incidence is rising in tandem with the global epidemic of obesity. Early diagnosis is key to improving survival, which at 5 years is less than 20% in advanced disease and over 90% in early-stage disease. As yet, there are no validated biological markers for its early detection. Advances in high-throughput technologies and machine learning techniques now offer unique and promising perspectives for biomarker discovery, especially through the integration of genomic, transcriptomic, proteomic, metabolomic and imaging data. Because the proteome closely mirrors the dynamic state of cells, tissues and organisms, proteomics has great potential to deliver clinically relevant biomarkers for cancer diagnosis. In this review, we present the current progress in endometrial cancer diagnostic biomarker discovery using proteomics. We describe the various mass spectrometry-based approaches and highlight the challenges inherent in biomarker discovery studies. We suggest novel strategies for endometrial cancer detection exploiting biologically important protein biomarkers and set the scene for future directions in endometrial cancer biomarker research.

Identification of prognosis markers for endometrial cancer by integrated analysis of DNA methylation and RNA-Seq data

Endometrial cancer is highly malignant and has a poor prognosis in the advanced stage, thus, prediction of its prognosis is important. DNA methylation has rapidly gained clinical attention as a biomarker for diagnostic, prognostic and predictive purposes in various cancers. In present study, differentially methylated positions and differentially expressed genes were identified according to DNA methylation and RNA-Seq data. Functional analyses and interaction network were performed to identify hub genes, and overall survival analysis of hub genes were validated. The top genes were evaluated by immunohistochemical staining of endometrial cancer tissues. The gene function was evaluated by cell growth curve after knockdown CDC20 and CCNA2 of endometrial cancer cell line. A total of 329 hypomethylated highly expressed genes and 359 hypermethylated lowly expressed genes were identified, and four hub genes were obtained according to the interaction network. Patients with low expression of CDC20 and CCNA2 showed better overall survival. The results also were demonstrated by the immunohistochemical staining. Cell growth curve also demonstrated that knockdown CDC20 and CCNA2 can suppress the cell proliferation. We have identified two aberrantly methylated genes, CDC20 and CCNA2 as novel biomarkers for precision diagnosis in EC.

Identification of DNA methylation signature to predict prognosis in gastric adenocarcinoma

Gastric adenocarcinoma is an important death-related cancer. To find factors related to survival and prognosis, and thus improve recovery prospects, a powerful signature is needed. DNA methylation plays an important role in gastric adenocarcinoma processes and development, and here we report on the search for a significant DNA methylation gene to aid with the earlier diagnosis of gastric adenocarcinoma patients. A Cox proportional risk regression analysis and random survival forest algorithm were used to analyze gastric adenocarcinoma patients' DNA methylation data from The Cancer Genome Atlas, a public database. DNA methylation gene signature consisting of five genes (SERPINA3, AP000357.4, GZMA, AC004702.2, and GREB1L) were selected. As the most accurate predictor, the area under the curve in the training and test group were 0.72 and 0.61, respectively. The signature was able to sort patients into high- and low-risk groups with meaningful overall survival rates (median: 18.36 vs 72.23 months, log-rank test, P < 0.001) in the training group, which predictive ability was validated in a test data set (median: 25.56 vs 58.80 months, log-rank test, P < 0.016). A multivariate Cox regression analysis showed the significant DNA methylation was an independent prediction prognostic factor for gastric adenocarcinoma patients. Functional analysis suggests that these signature genes may be related to pathways and biological processes associated with tumorigenesis. The significant DNA methylation gene could be a novel prediction and prognostic biomarker that both aids in the treatment and predicts the overall survival likelihoods of gastric adenocarcinoma patients.

New perspectives on screening and early detection of endometrial cancer

Due to the anatomical continuity of the uterine cavity with the cervix, genomic exploitation of material from routine Pap smears and other noninvasive sampling methods represent a unique opportunity to detect signs of disease using biological material shed from the upper genital tract. Recent research findings offer a promising perspective in the detection of endometrial cancer, but certain questions need to be addressed in order to accelerate the implementation of novel technologies in a routine screening or clinical setting. We discuss here new perspectives on detection of endometrial cancer using genomic and other biomarkers in minimally invasive sampling methods with a special focus on public health classic screening criteria, highlighting current gaps in knowledge.

Early Epigenetic Markers for Precision Medicine

Over the last years, epigenetic changes, including DNA methylation and histone modifications detected in early tumorigenesis and cancer progression, have been proposed as biomarkers for cancer detection, tumor prognosis, and prediction to treatment response. Importantly for the clinical use of DNA methylation biomarkers, specific methylation signatures can be detected in many body fluids including serum/plasma samples. Several of these potential epigenetic biomarkers detected in women's cancers, colorectal cancers, prostate, pancreatic, gastric, and lung cancers are discussed. Studies conducted in breast cancer, for example, found that aberrant methylation detection of several genes in serum DNA and genome-wide epigenetic change could be used for early breast cancer diagnosis and prediction of breast cancer risk. In colorectal cancers, numerous studies have been conducted to identify specific methylation markers important for CRC detection and in fact clinical assays evaluating the methylation status of SEPT19 gene and vimentin, became commercially available. Furthermore, some epigenetic changes detected in gastric washes have been suggested as potential circulating noninvasive biomarkers for the early detection of gastric cancers. For the early detection of prostate cancer, few epigenetic markers have shown a better sensitivity and specificity than serum PSA, indicating that the inclusion of these markers together with current screening tools, could improve early diagnosis and may reduce unnecessary repeat biopsies. Similarly, in pancreatic cancers, abnormal DNA methylation of several genes including NPTX2, have been suggested as a diagnostic biomarker. Epigenetic dysregulation was also observed in several tumor suppressor genes and miRNAs in lung cancer patients, suggesting the important role of these changes in cancer initiation and progression. In conclusion, epigenetic changes detected in biological fluids could play an essential role in the early detection of several cancer types and this may have a great impact for the cancer precision medicine field.

The role of biomarkers in endometrial cancer and hyperplasia: a literature review

INTRODUCTION

Endometrial cancer is the most common gynaecological cancer and its incidence is rising due to increasing obesity rates. We are also seeing an increasing trend of young women diagnosed with either endometrial cancer or its precancerous state, endometrial hyperplasia. Diagnosis is dependent on invasive testing and there is no screening tool available for either general or high-risk population groups. Whilst vast amounts of research have been undertaken in higher-profile cancers such as ovarian and cervical, endometrial cancer is comparatively less investigated.

AIM

In this literature review, we summarise the existing literature in understanding the role of tumour biomarkers for endometrial cancer and its preceding condition of endometrial hyperplasia.

METHOD

NICE Healthcare Databases Search tool was used to search Embase, Medline and PubMed databases for relevant articles.

CONCLUSION

There is currently no routinely used biomarker in endometrial cancer for diagnostic or prognostic purposes. Given the establishment of new genomic classifications of endometrial cancers, the use of biomarkers to drive therapeutic approaches will be the cornerstone for individualised cancer care in the coming decades.

Methylation status of KLF4 and HS3ST2 genes as predictors of endometrial cancer and hyperplastic endometrial lesions

Endometrial carcinoma is one of the most common tumours in developed countries. In addition to the active role of genetic factors, epigenetic changes also have an important effect. The present study analysed the methylation status of kruppel like factor 4 (KLF4) and heparan sulfate‑glucosamine 3‑sulfotransferase 2 (HS3ST2) genes in three endometrial tissue types for carcinoma prediction. The sample comprised 91 women with histologically‑confirmed endometrial carcinoma (64.16±9.64 years old), 36 women with hyperplasia (53.39±9.64 years old) and 45 with no signs or symptoms of malignancy (48.53±11.11 years old). The CpG dinucleotide methylation levels were examined by quantitative pyrosequencing, and the discrimination accuracy of the model was calculated using the Random Forest classification algorithm of the area under the ROC curve (AUC). The mean values of KLF4 and HS3ST2 methylation indices were 23.83±11.39 and 8.52±2.57 in the control samples; 30.40±8.52 and 33.76±20.66 in hyperplasia and 34.72±10.79 and 34.49±18.39 in the cancerous tissues. Multinomial logistic regression indicated that the HS3ST2 CpG1 methylation status is a predictor of hyperplasia (P<0.05) and that the KLF4 CpG2 dinucleotide can predict carcinoma formation (P<0.001). The AUC value of 0.95 indicates high discrimination accuracy of the CpG nucleotides methylation status model between the controls and the two other diagnoses. The results of the present study establish the likelihood that aberrations in KLF4 and HS3ST2 gene methylation levels are important in the development of endometrial hyperplasia and carcinoma, with hyperplasia an intermediate step between healthy and tumour tissues.

Association of Endometrial Cancer Risk With Postmenopausal Bleeding in Women: A Systematic Review and Meta-analysis

IMPORTANCE

As the worldwide burden of endometrial cancer continues to rise, interest is growing in the evaluation of early detection and prevention strategies among women at increased risk. Focusing efforts on women with postmenopausal bleeding (PMB), a common symptom of endometrial cancer, may be a useful strategy; however, PMB is not specific for endometrial cancer and is often caused by benign conditions.

OBJECTIVE

To provide a reference of the prevalence of PMB in endometrial cancers and the risk of endometrial cancer in women with PMB.

DATA SOURCES

For this systematic review and meta-analysis, PubMed and Embase were searched for English-language studies published January 1, 1977, through January 31, 2017.

STUDY SELECTION

Observational studies reporting the prevalence of PMB in women with endometrial cancer and the risk of endometrial cancer in women with PMB in unselected populations were selected.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers evaluated study quality and risk of bias using items from the Newcastle-Ottawa Quality Assessment Scale and the Quality Assessment of Diagnostic Accuracy Studies tool. Studies that included highly selected populations, lacked detailed inclusion criteria, and/or included 25 or fewer women were excluded.

MAIN OUTCOMES AND MEASURES

The pooled prevalence of PMB in women with endometrial cancer and the risk of endometrial cancer in women with PMB.

RESULTS

A total of 129 unique studies, including 34 432 unique patients with PMB and 6358 with endometrial cancer (40 790 women), were analyzed. The pooled prevalence of PMB among women with endometrial cancer was 91% (95% CI, 87%-93%), irrespective of tumor stage. The pooled risk of endometrial cancer among women with PMB was 9% (95% CI, 8%-11%), with estimates varying by use of hormone therapy (range, 7% [95% CI, 6%-9%] to 12% [95% CI, 9%-15%]; P < .001 for heterogeneity) and geographic region (range, 5% [95% CI, 3%-11%] in North America to 13% [95% CI, 9%-19%] in Western Europe; P = .09 for heterogeneity).

CONCLUSIONS AND RELEVANCE

Early detection strategies focused on women with PMB have the potential to capture as many as 90% of endometrial cancers; however, most women with PMB will not be diagnosed with endometrial cancer. These results can aid in the assessment of the potential clinical value of new early detection markers and clinical management strategies for endometrial cancer and will help to inform clinical and epidemiologic risk prediction models to support decision making.

Epigenetic loss of heparan sulfate 3-O-sulfation sensitizes ovarian carcinoma to oncogenic signals and predicts prognosis

Precision medicine requires markers for therapeutic guidance. The purpose of this study was to determine whether epithelial ovarian cancer (EOC) epigenetics can lead to the identification of biomarkers for precision medicine. Through integrative methylomics, we discovered and validated the epigenetic signature of NEFH and HS3ST2 as an independent prognostic factor for type II EOC in our dataset (n = 84), and two independent methylomics datasets (total n = 467). Integrated transcriptomics dataset (n = 1147) and tissue microarrays (n = 54) of HS3ST2 also related to high-methylation statuses and the EOC prognosis. Mechanistic explorations of HS3ST2 have assessed responses to oncogenic stimulations such as IL-6, EGF, and FGF2 in cancer cells. The combination of HS3ST2 and various oncogenic ligands also confers the worse outcome. 3-O-sulfation of heparan sulfate by HS3ST2 makes ovarian cancer cells intrinsically sensitive to oncogenic signals, which sheds new light on the application of HS3ST2 as a companion diagnostic for targeted therapy using kinase inhibitors or therapeutic antibodies.

Detect differentially methylated regions using non-homogeneous hidden Markov model for methylation array data

Motivation

DNA methylation is an important epigenetic mechanism in gene regulation and the detection of differentially methylated regions (DMRs) is enthralling for many disease studies. There are several aspects that we can improve over existing DMR detection methods: (i) methylation statuses of nearby CpG sites are highly correlated, but this fact has seldom been modelled rigorously due to the uneven spacing; (ii) it is practically important to be able to handle both paired and unpaired samples; and (iii) the capability to detect DMRs from a single pair of samples is demanded.

Results

We present DMRMark (DMR detection based on non-homogeneous hidden Markov model), a novel Bayesian framework for detecting DMRs from methylation array data. It combines the constrained Gaussian mixture model that incorporates the biological knowledge with the non-homogeneous hidden Markov model that models spatial correlation. Unlike existing methods, our DMR detection is achieved without predefined boundaries or decision windows. Furthermore, our method can detect DMRs from a single pair of samples and can also incorporate unpaired samples. Both simulation studies and real datasets from The Cancer Genome Atlas showed the significant improvement of DMRMark over other methods.

Availability and implementation

DMRMark is freely available as an R package at the CRAN R package repository.

Contact

xfan@cuhk.edu.hk.

Supplementary information

Supplementary data are available at Bioinformatics online.

The feasibility of detecting endometrial and ovarian cancer using DNA methylation biomarkers in cervical scrapings

Objective

We hypothesized that DNA methylation of development-related genes may occur in endometrial cancer (EC)/ovarian cancer (OC) and may be detected in cervical scrapings.

Methods

We tested methylation status by quantitative methylation-specific polymerase chain reaction for 14 genes in DNA pools of endometrial and OC tissues. Tissues of EC/normal endometrium, OC/normal ovary, were verified in training set using cervical scrapings of 10 EC/10 OC patients and 10 controls, and further validated in the testing set using independent cervical scrapings in 30 EC/30 OC patients and 30 controls. We generated cutoff values of methylation index (M-index) from cervical scrapings to distinguish between cancer patients and control. Sensitivity/specificity of DNA methylation biomarkers in detecting EC and OC was calculated.

Results

Of 14 genes, 4 (PTGDR, HS3ST2, POU4F3, MAGI2) showed hypermethylation in EC and OC tissues, and were verified in training set. POU4F3 and MAGI2 exhibited hypermethylation in training set were validated in independent cases. The mean M-index of POU4F3 is 78.28 in EC and 20.36 in OC, which are higher than that in controls (6.59; p<0.001 and p=0.100, respectively), and that of MAGI2 is 246.0 in EC and 12.2 in OC, which is significantly higher that than in controls (2.85; p<0.001 and p=0.480, respectively). Sensitivity and specificity of POU4F3/MAGI2 were 83%–90% and 69%–75% for detection of EC, and 61% and 62%–69% for the detection of OC.

Conclusion

The findings demonstrate the potential of EC/OC detection through testing for DNA methylation in cervical scrapings.

Exploration of DNA methylation markers for diagnosis and prognosis of patients with endometrial cancer

The accurate diagnosis of endometrial cancer (EC) holds great promise for improving its treatment choice and prognosis prediction. This work aimed to identify diagnostic biomarkers for differentiating EC tumors from tumors in other tissues, as well as prognostic signatures for predicting survival in EC patients. We identified 48 tissue-specific markers using a cohort of genome-wide methylation data from three common gynecological tumors and their corresponding normal tissues. A diagnostic classifier was constructed based on these 48 CpG markers that could predict cancerous versus normal tissue with an overall correct rate of 98.3% in the entire repository. Fifteen CpG markers associated with the overall survival (OS) and development of EC were also identified based on the methylation patterns of the EC samples. A prognostic model that aggregated these prognostic CpG markers was established and shown to have a higher discriminative ability to distinguish EC patients with an elevated risk of mortality than the FIGO staging system and several other clinical prognostic variables. This study presents the utility of DNA methylation in identifying biomarkers for the diagnosis and prognosis of EC and will help improve our understanding of the underlying mechanisms involved in the development of EC.

The diagnostic role of DNA methylation in sporadic endometrial cancer: a systematic review and meta-analysis

Background

Although increasing numbers of methylated genes have been identified as biomarkers for endometrial cancer, the results have been inconsistent. We therefore carried out a systematic review and meta-analysis to evaluate the diagnostic accuracy of methylated genes as markers for sporadic endometrial cancer.

Results

A total of 22 studies including 1930 participants (sporadic endometrial cancer patients and normal individuals) met our eligibility criteria. The pooled sensitivity and specificity were 0.93 (95% confidence interval: 0.91−0.94) and 0.48 (95% confidence interval: 0.46–0.50), respectively. The area under the summary receiver operating characteristic curve was 0.8834. The presence of DNA methylation was significantly associated with lymph node metastasis of endometrial cancer (pooled odds ratio: 0.28, 95% confidence interval: 0.15–0.52, p < 0.001).

Materials and Methods

We searched the relevant literature systematically using the PubMed and Web of Science databases up to April 2017. Diagnostic accuracy variables were pooled and analyzed using Meta-DiSc software. Sensitivity analysis and publication bias were evaluated using Review Manager.

Conclusions

This meta-analysis suggests that the detection of DNA methylation is associated with lymph node metastasis, with high sensitivity but relatively low specificity for the diagnosis of sporadic endometrial cancer.

Novel approaches to early detection of endometrial cancer

PURPOSE OF REVIEW

Detection of endometrial cancer at an early stage leads to better oncologic outcomes. To date, a screening test for endometrial cancer does not exist.

RECENT FINDINGS

Evolving knowledge of molecular changes involved in endometrial cancer carcinogenesis paired with sensitive and high-throughput technological advancements are a promising combination that can be leveraged to detect tumor DNA and proteins. These molecular biomarkers can be identified in biospecimens collected via minimally invasive and noninvasive approaches. Exploiting lower genital tract secretions as a biospecimen also allows for patient self-sampling.

SUMMARY

Successful development of a screening test for endometrial cancer using self-collected lower genital tract biospecimens has the potential to increase accessibility to care and improve patient compliance.

Epigenetics in endometrial carcinogenesis - part 1: DNA methylation

Carcinogenesis is a multistep multifactorial process that involves the accumulation of genetic and epigenetic alterations. In the past two decades, there has been an exponential growth of knowledge establishing the importance of epigenetic changes in cancer. Our work focused on reviewing the main role of epigenetics in the pathogenesis of endometrial carcinoma, highlighting the reported results concerning each epigenetic mechanistic layer. The present review is the first part of this work, in which we examined the contribution of DNA methylation alterations for endometrial carcinogenesis.

Quantitative DNA methylation analysis of selected genes in endometrial carcinogenesis

OBJECTIVE

Most endometrial carcinomas appear to develop from precursors (e.g., endometrial hyperplasia) that progress for several years. Patients who are ultimately diagnosed with carcinoma often present clinically with complaints of abnormal vaginal bleeding years before diagnosis, which offers an opportunity for early diagnosis and curative treatment. The analysis of DNA methylation may be used as a method for detecting endometrial cancer (EC). To test the potential clinical application of this method, we used quantitative methylation analysis of five genes in a full spectrum of endometrial lesions.

MATERIALS AND METHODS

This hospital-based, prospective, case-controlled study was conducted on 68 patients, which included patients who had a normal endometrium (n = 18), hyperplasia of the endometrium (n = 24), and EC (n = 26). Methylation levels of the following genes were determined by using real-time methylation-specific polymerase chain reaction (PCR) amplification: zinc finger protein 177 (ZNF177), collagen type XIV α1 (COL14A1), dihydropyrimidinase-like 4 (DPYSL4), homeobox A9 (HOXA9), transmembrane protein with epidermal growth factor-like and two follistatin-like domains 2 (TMEFF2). The methylation index (MI) cutoff values for the different diagnoses were determined to test the sensitivity and specificity of the method and to generate the receiver operating characteristic (ROC) curves. The Mann-Whitney U test was used to test between-group differences in the MI.

RESULTS

The MI of the five genes was significantly higher in EC than the MIs in specimens of hyperplasia of endometrium and normal appearance (p < 0.001). The ROC analysis demonstrated that the sensitivity, specificity, and accuracy for detecting EC were 92.3%, 94.4%, and 95.1%, respectively, for ZNF177; 92.3%, 94.4%, and 95.7%, respectively, for COL14A1; 80.8%, 94.4%, and 81.4%, respectively, for HOXA9; 65.4%, 94.4%, and 89.5%, respectively, for TMEFF2; and 61.5%, 94.4%, and 63.3%, respectively, for DPYSL4. The combined testing of ZNF177 and COL14A1 had the best specificity (100%), but compromised sensitivity (88.5%).

CONCLUSION

Promoter methylation of ZNF177, COL14A1, HOXA9, DPYSL4, and TMEFF2 genes is a frequent epigenetic event in EC. Furthermore, the epigenetic hypermethylation of TMEFF2 may be a valuable marker for identifying undetected EC within endometrial hyperplasia.

Methods for genome-wide DNA methylation analysis in human cancer

Aberrant DNA methylation is considered to be one of the most common hallmarks of cancer. Several recent advances in assessing the DNA methylome provide great promise for deciphering the cancer-specific DNA methylation patterns. Herein, we present the current key technologies used to detect high-throughput genome-wide DNA methylation, and the available cancer-associated methylation databases. Additionally, we focus on the computational methods for preprocessing, analyzing and interpreting the cancer methylome data. It not only discusses the challenges of the differentially methylated region calling and the prediction model construction but also highlights the biomarker investigation for cancer diagnosis, prognosis and response to treatment. Finally, some emerging challenges in the computational analysis of cancer methylome data are summarized.

PTEN expression in benign human endometrial tissue and cancer in relation to endometrial cancer risk factors

PURPOSE

Clonal loss of PTEN expression occurs frequently in endometrial carcinoma and endometrial hyperplasia. Limited data from immunohistochemical studies suggest that PTEN-null appearing endometrial glands are detectable in women without pathologic abnormalities, but the relationship of PTEN expression to endometrial cancer risk factors has not been extensively explored. We evaluated relationships between endometrial cancer risk factors and loss of PTEN expression in a set of benign endometrial samples prospectively collected from women undergoing hysterectomy and in endometrial cancer tissues from a population-based case-control study.

METHODS

We used a validated PTEN immunohistochemical assay to assess expression in epidemiological studies designed to assess benign endometrium [Benign Reproductive Tissue Evaluation Study (n = 73); Einstein Endometrium Study (n = 19)], and endometrial cancer [Polish Endometrial Cancer Study (n = 148)] tissues. Associations between endometrial cancer risk factors (collected via study-specific risk factor questionnaires) and PTEN expression in endometrial tissues were determined using Fisher's exact tests.

RESULTS

PTEN loss was detected in 19% of benign endometrial tissues versus 55% in endometrial cancers. NSAID use was statistically significantly associated with PTEN loss in the benign endometrium (p = 0.02).

CONCLUSION

Our data demonstrate that PTEN loss is detectable in endometrial tissues that are benign and malignant, with substantially more frequent loss in endometrial cancer compared with benign endometrium. However, alterations in expression were unrelated to most risk factors in this analysis, except for the association with NSAID use, which may represent a chance finding or reverse causality among patients with endometriosis who may have PTEN pathway abnormalities in eutopic endometrium. Further evaluation of factors associated with PTEN loss and long-term follow-up of women with PTEN-null endometrial glands may be useful in understanding early events in endometrial carcinogenesis.

Sex Differences Research, Precision Medicine, and the Future of Women's Health

The National Institutes of Health's (NIH) commitment to improving health outcomes for women and men through rigorous science has been compromised by the lack of basic science evidence obtained from female animals. To correct this limitation, in June 2015 the NIH announced expectations that "sex," as a biological variable, be included into research design and analysis in studies of vertebrate animals and humans (NOT-OD-15-102). Scientists must take the responsibility to implement this directive. However, in doing so, there is a risk that attention could be restricted to only studies of direct comparison between female/women and male/men. By contrast, understanding how sex influences health and disease needs to take a programmatic approach that includes the study of sex-specific conditions. A programmatic approach will assure the advancement of knowledge to improve women's health.

Thyroid cancer GWAS identifies 10q26.12 and 6q14.1 as novel susceptibility loci and reveals genetic heterogeneity among populations

Thyroid cancer is the most heritable cancer of all those not displaying typical Mendelian inheritance. However, most of the genetic factors that would explain the high heritability remain unknown. Our aim was to identify additional common genetic variants associated with susceptibility to this disease. In order to do so, we performed a genome-wide association study in a series of 398 cases and 502 controls from Spain, followed by a replication in four well-defined Southern European case-control collections contributing a total of 1,422 cases and 1,908 controls. The association between the variation at the 9q22 locus near FOXE1 and thyroid cancer risk was consistent across all series, with several SNPs identified (rs7028661: OR = 1.64, p = 1.0 × 10(-22) , rs7037324: OR = 1.54, p = 1.2 × 10(-17) ). Moreover, the rare alleles of three SNPs (rs2997312, rs10788123 and rs1254167) at 10q26.12 showed suggestive evidence of association with higher risk of the disease (OR = 1.35, p = 1.2 × 10(-04) , OR = 1.26, p = 5.2 × 10(-04) and OR = 1.38, p = 5.9 × 10(-05) , respectively). Finally, the rare allele of rs4075570 at 6q14.1 conferred protection in the series studied (OR = 0.82, p = 2.0 × 10(-04) ). This study suggests that heterogeneity in genetic susceptibility between populations is a key feature to take into account when exploring genetic risk factors related to this disease.