High Detection Rate for Non-Muscle-Invasive Bladder Cancer Using an Approved DNA Methylation Signature Test.

INTRODUCTION: Cystoscopy and transurethral resection are the current reference standard tests to diagnose and histologically confirm non-muscle-invasive bladder cancer (NMIBC). In other tumor entities (ie, colon carcinoma, cervical cancer), DNA methylation markers have been approved as diagnostic tests with high diagnostic power. In our case-control study, we used an approved molecular cervical cancer diagnostics test that includes 6 DNA methylation markers (GynTect) for the detection of bladder cancer. PATIENTS AND METHODS: We included samples from 40 patients with bladder cancer and 34 control subjects. In a pilot study, we analyzed DNA methylation in 38 tumor tissues and 4 healthy ureters using methylation-specific polymerase chain reaction. Subsequently, we determined the sensitivity and specificity of the GynTect for the detection of bladder cancer in urine sediments from 40 patients with bladder cancer and 30 control subjects with benign prostatic hyperplasia or urolithiasis. RESULTS: The markers showed very different methylation rates in the NMIBC tissues, ranging from 2.6% to 78.9%. No methylation of any of the markers was detectable in the healthy ureters. Using the urine sediments from the patients with cancer and control subjects, we found surprisingly high sensitivity and specificity for the GynTect assay (60% and 96.7%, respectively). The application of different algorithms for evaluation of the markers included in GynTect resulted in a sensitivity of ≤ 90% and specificity of ≤ 100%. CONCLUSION: The GynTect assay, originally designed for cervical cancer diagnostics, showed unexpectedly high diagnostic accuracy for bladder cancer detection. The inclusion of additional methylation markers might allow for the development of a suitable diagnostic marker set based on the GynTect test for NMIBC diagnostics.

Comparing diagnostic and prognostic performance of two-gene promoter methylation panels in tissue biopsies and urines of prostate cancer patients.

BACKGROUND: Prostate cancer (PCa) is one of the most common cancers among men worldwide. Current screening methods for PCa display limited sensitivity and specificity, not stratifying for disease aggressiveness. Hence, development and validation of new molecular markers is needed. Aberrant gene promoter methylation is common in PCa and has shown promise as clinical biomarker. Herein, we assessed and compared the diagnostic and prognostic performance of two-gene panel promoter methylation in the same sample sets. METHODS: Promoter methylation of panel #1 (singleplex-miR-34b/c and miR-193b) and panel #2 (multiplex-APC, GSTP1, and RARß2) was evaluated using MethyLight methodology in two different cohorts [prostate biopsy (#1) and urine sediment (#2)]. Biomarkers' diagnostic (validity estimates) and prognostic (disease-specific survival, disease-free survival, and progression-free survival) performance was assessed. RESULTS: Promoter methylation levels of both panels showed the highest levels in PCa samples in both cohorts. In tissue samples, methylation panel #1 and panel #2 detected PCa with AUC of 0.9775 and 1.0, respectively, whereas in urine samples, panel #2 demonstrated superior performance although a combination of miR-34b/c, miR-193b, APC, and RARß2 disclosed the best results (AUC = 0.9817). Furthermore, higher mir-34b/c and panel #2 methylation independently predicted for shorter DSS. Furthermore, time-dependent ROC curves showed that both miR-34b/c and GSTP1 methylation levels identify with impressive performance patients that relapse up to 15 years after diagnosis (AUC = 0.751 and AUC = 0.765, respectively). CONCLUSIONS: We concluded that quantitative gene panel promoter methylation might be a clinically useful tool for PCa non-invasive detection and risk stratification for disease aggressiveness in both tissue biopsies and urines.

A urine-based methylation signature for risk stratification within low-risk prostate cancer.

BACKGROUND: Prostate cancer overdiagnosis and overtreatment represents a major problem. Many men with low-grade disease on biopsy are undergraded and they harbour high-grade disease at prostatectomy with no reliable way to identify these men. We used a novel urine-based 2-gene methylation test to identify prostate cancers with aggressive features. METHODS: Following a proof of concept study in 100 post-radical prostatectomy tissue samples, urine samples were tested from 665 men at multiple U.S. centers undergoing prostate needle biopsy for elevated prostate-specific antigen (2-10 ng ml(-1)). A prediction model was then developed from a combination of clinical factors and the urine-based markers. It was then prospectively tested for accurate prediction of adverse disease (surgical Gleason score ⩾7 and/or a pathological stage ⩾T3a) using urine from a separate cohort of 96 men before radical prostatectomy. RESULTS: Among pre-prostatectomy men with a biopsy Gleason score <7, 41% had adverse disease of which 100% were correctly identified by the test with a negative predictive value of 100% (95% confidence interval, 86-100%). CONCLUSIONS: This urine-based test accurately identifies men with clinical low-risk disease who do not have adverse pathology in their prostates and would be excellent candidates for active surveillance.

Novel multiplex MethyLight protocol for detection of DNA methylation in patient tissues and bodily fluids.

Aberrant DNA methylation is a hallmark of cancer and is an important potential biomarker. Particularly, combined analysis of a panel of hypermethylated genes shows the most promising clinical performance. Herein, we developed, optimized and standardized a multiplex MethyLight assay to simultaneously detect hypermethylation of APC, HOXD3 and TGFB2 in DNA extracted from prostate cancer (PCa) cell lines, archival tissue specimens, and urine samples. We established that the assay is capable of discriminating between fully methylated and unmethylated alleles with 100% specificity and demonstrated the assay as highly accurate and reproducible as the singleplex approach. For proof of principle, we analyzed the methylation status of these genes in tissue and urine samples of PCa patients as well as PCa-free controls. These data show that the multiplex MethyLight assay offers a significant advantage when working with limited quantities of DNA and has potential applications in research and clinical settings.

Urinary biomarkers for prostate cancer: a review.

Although the routine use of serum prostate-specific antigen (PSA) testing has undoubtedly increased prostate cancer (PCa) detection, one of its main drawbacks is its lack of specificity. As a consequence, many men undergo unnecessary biopsies or treatments for indolent tumours. PCa-specific markers are needed for the early detection of the disease and the prediction of aggressiveness of a prostate tumour. Since PCa is a heterogeneous disease, a panel of tumour markers is fundamental for a more precise diagnosis. Several biomarkers are promising due to their specificity for the disease in tissue. However, tissue is unsuitable as a possible screening tool. Since urine can be easily obtained in a non-invasive manner, it is a promising substrate for biomarker testing. This article reviews the biomarkers for the non-invasive testing of PCa in urine.