Molecular screening for bladder cancer: progress and potential

Metabolomic Signatures of Treatment Response in Bladder Cancer

Bladder cancer (BC) stands as one of the most prevalent urological malignancies, with over 500 thousand newly diagnosed cases annually. Treatment decisions in BC depend on factors like the risk of recurrence, the type of tumor, and the stage of the disease. While standard therapeutic approaches encompass transurethral resection of the bladder tumor, radical cystectomy, and chemo- or immunotherapy, these methods exhibit limited efficacy in mitigating the aggressive and recurrent nature of bladder tumors. To overcome this challenge, it is crucial to develop innovative methods for monitoring and predicting treatment responses among patients with BC. Metabolomics is gaining recognition as a promising approach for discovering biomarkers. It has the potential to reveal metabolic disruptions that precisely reflect how BC patients respond to particular treatments, providing a revolutionary method to improve accuracy in monitoring and predicting outcomes. In this article, we present a comprehensive review of studies employing metabolomics approaches to investigate the metabolic responses associated with different treatment modalities for BC. The review encompasses an exploration of various models, samples, and analytical techniques applied in this context. Special emphasis is placed on the reported changes in metabolite levels derived from these studies, highlighting their potential as biomarkers for personalized medicine in BC.

Molecular Markers for Bladder Cancer Screening: An Insight into Bladder Cancer and FDA-Approved Biomarkers

Bladder cancer is one of the most financially burdensome cancers globally, from its diagnostic to its terminal stages. The impact it imposes on patients and the medical community is substantial, exacerbated by the absence of disease-specific characteristics and limited disease-free spans. Frequent recurrences, impacting nearly half of the diagnosed population, require frequent and invasive monitoring. Given the advancing comprehension of its etiology and attributes, bladder cancer is an appealing candidate for screening strategies. Cystoscopy is the current gold standard for bladder cancer detection, but it is invasive and has the potential for undesired complications and elevated costs. Although urine cytology is a supplementary tool in select instances, its efficacy is limited due to its restricted sensitivity, mainly when targeting low-grade tumors. Although most of these assays exhibit higher sensitivity than urine cytology, clinical guidelines do not currently incorporate them. Consequently, it is necessary to explore novel screening assays to identify distinctive alterations exclusive to bladder cancer. Thus, integrating potential molecular assays requires further investigation through more extensive validation studies. Within this article, we offer a comprehensive overview of the critical features of bladder cancer while conducting a thorough analysis of the FDA-approved assays designed to diagnose and monitor its recurrences.

Roles of non-coding RNAs in the metabolism and pathogenesis of bladder cancer

Bladder cancer (BC) is featured as the second most common malignancy of the urinary tract worldwide with few treatments leading to high incidence and mortality. It stayed a virtually intractable disease, and efforts to identify innovative and effective therapies are urgently needed. At present, more and more evidence shows the importance of non-coding RNA (ncRNA) for disease-related study, diagnosis, and treatment of diverse types of malignancies. Recent evidence suggests that dysregulated functions of ncRNAs are closely associated with the pathogenesis of numerous cancers including BC. The detailed mechanisms underlying the dysregulated role of ncRNAs in cancer progression are still not fully understood. This review mainly summarizes recent findings on regulatory mechanisms of the ncRNAs, long non-coding RNAs, microRNAs, and circular RNAs, in cancer progression or suppression and focuses on the predictive values of ncRNAs-related signatures in BC clinical outcomes. A deeper understanding of the ncRNA interactive network could be compelling framework for developing biomarker-guided clinical trials.

Integrative Multi-Omics Analysis for the Determination of Non-Muscle Invasive vs. Muscle Invasive Bladder Cancer: A Pilot Study

Objectives: The molecular landscape of non-muscle-invasive (NMIBC) and muscle-invasive (MIBC) bladder cancer based on molecular characteristics is essential but poorly understood. In this pilot study we aimed to identify a multi-omics signature that can distinguish MIBC from NMIBC. Such a signature can assist in finding potential mechanistic biomarkers and druggable targets. Methods: Patients diagnosed with NMIBC (n = 15) and MIBC (n = 11) were recruited at a tertiary-care hospital in Nanjing from 1 April 2021, and 31 July 2021. Blood, urine and stool samples per participant were collected, in which the serum metabolome, urine metabolome, gut microbiome, and serum extracellular vesicles (EV) proteome were quantified. The differences of the global profiles and individual omics measure between NMIBC vs. MIBC were assessed by permutational multivariate analysis and the Mann–Whitney test, respectively. Logistic regression analysis was used to assess the association of each identified analyte with NMIBC vs. MIBC, and the Spearman correlation was used to investigate the correlations between identified analytes, where both were adjusted for age, sex and smoking status. Results: Among 3168 multi-omics measures that passed the quality control, 159 were identified to be differentiated in NMIBC vs. MIBC. Of these, 46 analytes were associated with bladder cancer progression. In addition, the global profiles showed significantly different urine metabolome (p = 0.029), gut microbiome (p = 0.036), and serum EV (extracellular vesicles) proteome (p = 0.039) but not serum metabolome (p = 0.059). We also observed 17 (35%) analytes that had been developed as drug targets. Multiple interactions were obtained between the identified analytes, whereas for the majority (61%), the number of interactions was at 11–20. Moreover, unconjugated bilirubin (p = 0.009) and white blood cell count (p = 0.006) were also shown to be different in NMIBC and MIBC, and associated with 11 identified omics analytes. Conclusions: The pilot study has shown promising to monitor the progression of bladder cancer by integrating multi-omics data and deserves further investigations.

Metabolomic Approaches for Detection and Identification of Biomarkers and Altered Pathways in Bladder Cancer

Metabolomic analysis has proven to be a useful tool in biomarker discovery and the molecular classification of cancers. In order to find new biomarkers, and to better understand its pathological behavior, bladder cancer also has been studied using a metabolomics approach. In this article, we review the literature on metabolomic studies of bladder cancer, focusing on the different available samples (urine, blood, tissue samples) used to perform the studies and their relative findings. Moreover, the multi-omic approach in bladder cancer research has found novel insights into its metabolic behavior, providing excellent start-points for new diagnostic and therapeutic strategies. Metabolomics data analysis can lead to the discovery of a “signature pathway” associated with the progression of bladder cancer; this aspect could be potentially valuable in predictions of clinical outcomes and the introduction of new treatments. However, further studies are needed to give stronger evidence and to make these tools feasible for use in clinical practice.

The effect of CT high-resolution imaging diagnosis based on deep residual network on the pathology of bladder cancer classification and staging

BACKGROUND AND OBJECTIVE

To study the high-resolution CT image based on deep residual network to efficiently and accurately predict the staging diagnosis of bladder tumors.

METHODS

The image was processed with super-resolution to restore the missing details of the image. The CT data of 75 bladder patients who were treated in our hospital from June to December 2013 were collected. And obtain the patient's classification and staging information through pathology, which is used to establish a model of ResNet structure combined with non-Local attention mechanism. The clinical data of 76 patients with bladder disease admitted to our hospital from May 2018 to August 2021 were randomly selected, and the imaging and accuracy of CT diagnosis were retrospectively analyzed.

RESULTS

52 cases were diagnosed <T1 stage, 16 cases belonged to T2 stage, 2 cases T3 stage, and 2 cases T4 stage. The sensitivity rate of experimental diagnosis was 94.74%, which was not significantly different from the sensitivity rate of preoperative pathological diagnosis.

CONCLUSION

CT based on deep residual network has high application value in the diagnosis and staging of bladder cancer, can effectively improve the diagnostic accuracy, and is worthy of clinical application.

Development and validation of pyroptosis-related lncRNAs prediction model for bladder cancer

Bladder cancer (BLCA) is one of the highly heterogeneous disorders accompanied by a poor prognosis. The present study aimed to construct a model based on pyroptosis-related long-stranded non-coding RNA (lncRNA) to evaluate the potential prognostic application in bladder cancer. The mRNA expression profiles of bladder cancer patients and corresponding clinical data were downloaded from the public database from The Cancer Genome Atlas (TCGA). Pyroptosis-related lncRNAs were identified by utilizing a co-expression network of pyroptosis-related genes and lncRNAs. The lncRNA was further screened by univariate Cox regression analysis. Finally, eight pyroptosis-related lncRNA markers were established using least absolute shrinkage and selection operator (Lasso) regression and multivariate Cox regression analyses. Patients were separated into high- and low-risk groups based on the performance value of the median risk score. Patients in the high-risk group had significantly poorer overall survival (OS) than those in the low-risk group (P<0.001). In multivariate Cox regression analysis, the risk score was an independent predictive factor of OS (HR > 1, P<0.01). The areas under the curve (AUCs) of the 3- and 5-year OS in the receiver operating characteristic (ROC) curve were 0.742 and 0.739, respectively. In conclusion, these eight pyroptosis-related lncRNA and their markers may be potential molecular markers and therapeutic targets for bladder cancer patients.

The human TRAM1 locus expresses circular RNAs

Numerous indirect and in silico produced evidences suggest circular RNAs (circRNA) in mammals while thorough experimental proofs of their existence have rarely been reported. Biological studies of circRNA, however, should be based on experimentally verified circRNAs. Here, we describe the identification of two circRNAs originating from the gene locus of the translocation associated membrane protein 1 (TRAM1). Linear and potentially circular TRAM1-specific transcripts were identified in a transcriptome analysis of urine RNA of bladder cancer (BCa) patients versus healthy donors. Thus, we first focused on the topology of TRAM1-specific transcripts. We describe conclusive experimental evidence for the existence of TRAM1-specific circRNAs in the human BCa cell lines ECV-304 and RT-4. PCR-based methodology followed by cloning and sequencing strongly indicated the circular topology of two TRAM1 RNAs. Further, studies with exon fusion sequence-specific antisense oligonucleotides (asON) and RNase H as well as studies in the use of RNase R contribute to conclusive set of experiments supporting the circular topology of TRAM1 transcripts. On the biological side, TRAM1-specific circRNAs showed low expression levels and minor differences in BCa cell lines while linear TRAM1 transcripts displayed down-regulated expression in the higher cancer stage model ECV-304 versus more differentiated RT-4 cells.

A Poliovirus Receptor (CD155)-Related Risk Signature Predicts the Prognosis of Bladder Cancer

Background

Bladder cancer is an aggressive and heterogeneous disease associated with high morbidity and mortality. And poliovirus receptor (PVR or CD155) played crucial roles in tumor immune microenvironment and cancer development. However, their association remains obscure.

Methods

A total of 797 patients from TCGA and GEO databases were employed in our study, in which 285 cases were set as the training cohort and 512 were defined as the validation cohort. Our own Xiangya cohort with 57 samples was also used for the validation. Survival differences were evaluated by Kaplan-Meier analysis between groups. The immune infiltration was evaluated by ESTIMATE, TIMER, and CIBERSORT algorithms. The risk signature was constructed by LASSO Cox regression analysis. And a nomogram model was generated subsequent to the multivariate Cox proportional hazards analysis to predict 3- and 5-year survival of patients with bladder cancer.

Results

PVR was overexpressed across various cancers including bladder cancer and related to poorer overall survival in bladder urothelial carcinoma (BLCA). Samples with higher World Health Organization (WHO) grade or higher tumor stage tended to express higher level of PVR. And PVR-related genes were involved in several immune processes and oncological pathways. When the patients were divided into low- and high-risk groups based on their risk scores, we found that patients in the high-risk group had shorter overall survival time. Besides, samples with high risk were consistently correlated with tumor hallmarks and higher abundance of immune infiltration. Additionally, chemotherapy showed potent efficacy in high-risk group. Moreover, a nomogram including clinicopathologic features and the established risk signature could predict 3- and 5-year survival in patients with bladder cancer.

Conclusion

Our study revealed that PVR was overexpressed and related to poor prognosis in bladder cancer. A risk signature and nomogram model based on PVR-related genes could predict the prognosis and therapeutic efficacy and were also associated with the immune infiltration in bladder cancer.

Novel Salt-Responsive SiO2@Cellulose Membranes Promote Continuous Gradient and Adjustable Transport Efficiency

Continuously growing interest in the controlled and tunable transport or separation of target molecules has attracted more attention recently. However, traditional "on-off" stimuli-responsive membranes are limited to nongradient feedback, which manifests as filtration efficiency that cannot be increased or decreased gradually along with the different stimuli conditions; indeed, only the transformation of on/off state is visible. Herein, we design and fabricate a series of robust salt-responsive SiO₂@cellulose membranes (SRMs) by simply combining salt-responsive poly[3-(dimethyl(4-vinylbenzyl)ammonium)propyl sulfonate] (polyDVBAPS)-modified SiO₂ nanoparticles and cellulose membranes under negative-pressure filtering. The antipolyelectrolyte effect induces stretch/shrinkage of polyDVBAPS chains inside the channels and facilities the directional aperture size and surface wettability variation, greatly enhancing the variability of interfacial transport and separation efficiency. Due to the linear salt-responsive feedback mechanism, the optimal SRMs achieve highly efficient target macromolecule separation (>75%) and rapid oil/saline separation (>97%) with a continuous gradient and adjustable permeability, instead of simply an "on-off" switch. The salt-responsive factors (SiO₂-polyDVBAPS) could be reversibly separated or self-assembled to membrane substrates; thus, SRMs achieved unprecedented repeatability and reusability even after long-term cyclic testing, which exceeds those of currently reported membranes. Such SRMs possess simultaneously a superfast responsive time, a controllable gradient permeability, a high gating ratio, and an excellent reusability, making our strategy a potentially exciting approach for efficient osmotic transportation and target molecule separation in a more controllable manner.

NMR-derived targeted serum metabolic biomarkers appraisal of bladder cancer: A pre- and post-operative evaluation

With high morbidity and mortality, urinary bladder cancer (BC) ranks fifth among common cancers globally. The inherent limitations of urine cytology and cystoscopy, and marginal enhancements in the rate of survival promt us to develop surrogate serum based metabolic biomarkers of screening, identification, and follow-up protocols of management for BC patients. Earlier, we exhibited that abnormal expression levels of dimethylamine (DMA), malonate, lactate, glutamine, histidine, and valine in serum may be used as signature metabolites to differentiate BC from healthy controls (HC) (J. Proteome Res. 2013; 12(12):5839-50). Here we further gauge and validate these observations by comparing pre-operative to post-operative follow-up BC patients. This study was conducted on 160 sera samples involving HC (n = 52), pre-operative (n = 55) and post-operative (n = 53) BC cases. ¹H nuclear magnetic resonance (NMR) spectroscopy was used to generate serum metabolic profiles and to gauge aberrantly expressed metabolites. The targeted metabolomic approach revealed that the expression levels of these signature metabolites were progressively and significantly decreased in post-operative follow-up at the interval of 30, 60, and 90 days compared to pre-operative BC sera samples and were maintained at HC levels. Serum metabolic biomarkers appear to be an inspiring and least-invasive tactic for detection and prognosticating BC patient follow-up.

Urinary Calprotectin loses specificity as tumour marker due to sterile leukocyturia associated with bladder cancer

BACKGROUND

Urinary Calprotectin, a mediator of the innate immune system, has been identified as a biomarker in bladder cancer. Our aim was to investigate the association between sterile leukocyturia and urinary Calprotectin in low-grade and high-grade bladder cancer.

MATERIALS AND METHODS

We performed a prospective cross-sectional study including 52 patients with bladder cancer and 40 healthy controls. Definition of sterile leukocyturia was > 5.0 leukocytes per visual field in absence of bacteriuria.

RESULTS

The rate of sterile leukocyturia in low-grade (60.0%) and high-grade (62.0%) bladder cancer was comparable (p = 0.87). However, the median absolute urinary leukocyte count in patients with sterile leukocyturia was significantly higher in high-grade than in low-grade bladder cancer (p < 0.01). Spearman correlation revealed a significant correlation between urinary Calprotectin and leucocyte concentration (R = 0.4, p < 0.001). Median urinary Calprotectin concentration was 4.5 times higher in bladder cancer patients with than in patients without sterile leukocyturia (p = 0.03). Subgroup analysis revealed a significant difference in urinary Calprotectin regarding the presence of sterile leukocyturia in high-grade patients (596.8 [91.8-1655.5] vs. 90.4 [28.0-202.3] ng ml-1, p = 0.02). Multivariate analysis identified the leukocyte concentration to be the only significant impact factor for urinary Calprotectin (OR 3.2, 95% CI 2.5-3.8, p = 0.001). Immunohistochemistry showed Calprotectin positive neutrophils and tumour cells in high-grade bladder cancer with sterile leukocyturia.

CONCLUSIONS

Urinary Calprotectin cannot be regarded as a specific tumour marker for bladder cancer, but rather as a surrogate parameter for tumour inflammation.

Molecular Prognostication in Bladder Cancer

Clinical outcomes for patients with bladder cancer have largely remained unchanged over the last three decades despite improvements in surgical techniques, perioperative therapies, and postoperative management. Current management still heavily relies on pathologic staging that does not always reflect an individual patient's risk. The genesis and progression of bladder cancer is now increasingly recognized as being a result of alterations in several pathways that affect the cell cycle, apoptosis, cellular signaling, gene regulation, immune modulation, angiogenesis, and tumor cell invasion. Multiplexed assessment of biomarkers associated with alterations in these pathways offers novel insights into tumor behavior while identifying panels that are capable of reproducibly predicting patient outcomes. Future management of bladder cancer will likely incorporate such prognostic molecular models for risk stratification and treatment personalization.

Three serum metabolite signatures for diagnosing low-grade and high-grade bladder cancer

To address the shortcomings of cystoscopy and urine cytology for detecting and grading bladder cancer (BC), ultrahigh performance liquid chromatography (UHPLC) coupled with Q-TOF mass spectrometry in conjunction with univariate and multivariate statistical analyses was employed as an alternative method for the diagnosis of BC. A series of differential serum metabolites were further identified for low-grade(LG) and high-grade(HG) BC patients, suggesting metabolic dysfunction in malignant proliferation, immune escape, differentiation, apoptosis and invasion of cancer cells in BC patients. In total, three serum metabolites including inosine, acetyl-N-formyl-5-methoxykynurenamine and PS(O-18:0/0:0) were selected by binary logistic regression analysis, and receiver operating characteristic (ROC) test based on their combined use for HG BC showed that the area under the curve (AUC) was 0.961 in the discovery set and 0.950 in the validation set when compared to LG BC. Likewise, this composite biomarker panel can also differentiate LG BC from healthy controls with the AUC of 0.993 and 0.991 in the discovery and validation set, respectively. This finding suggested that this composite serum metabolite signature was a promising and less invasive classifier for probing and grading BC, which deserved to be further investigated in larger samples.

Urinary tract cancers: An overview for general practice

Urinary tract cancers are common and comprise a gamut of lesions ranging from small benign tumors to aggressive neoplasms with high mortality. The predominant urinary tract malignancy is bladder cancer. The clinical challenge is early detection and adequate follow-up because recurrence is high and delayed diagnosis is associated with poor prognosis. Primary care physicians form a key part of the management apparatus for these patients and may be responsible for ensuring adequate ongoing surveillance. This article aims to outline the evaluation of patients in whom urinary tract cancer is suspected and briefly review the general principles of treatment.

Discovery of urine biomarkers for bladder cancer via global metabolomics

Bladder cancer (BC) is latent in its early stage and lethal in its late stage. Therefore, early diagnosis and intervention are essential for successful BC treatment. Considering the limitations of current diagnostic tools, noninvasive biomarkers that are both highly sensitive and specific are needed to improve the overall survival and quality of life of patients. With the advent of systems biology, "-omics" technologies have been developed over the past few decades. As a promising member, global metabolomics has increasingly been found to have clear potential for biomarker discovery. However, urinary metabolomics studies related to BC have lagged behind those of other urinary cancers, and major findings have not been systematically reported. The objective of this review is to comprehensively list the currently identified potential urinary metabolite biomarkers for BC.

Molecular substratification of bladder cancer: moving towards individualized patient management

Despite advances in surgical techniques, perioperative therapies and postoperative management, outcomes for patients with bladder cancer have largely remained unchanged. Current management of bladder cancer still relies on pathologic staging that does not always reflect the risk for an individual patient. Studies assessing molecular alterations in individual tumors are offering insights into the myriad of cellular pathways that are deregulated in bladder tumorigenesis and progression. Alterations in pathways involved in cell-cycle regulation, apoptosis, cell signaling, angiogenesis and tumor-cell invasion have been shown to influence disease behavior. High-throughput assays are now allowing multiplexed assessment of biomarker alterations, thereby enabling characterization of novel molecular subtypes of bladder cancer. Such approaches have also been used for discovery and validation of robust prognostic molecular signatures. The future of bladder cancer management will rely on the use of validated multimarker panels for risk stratification, optimal surgical management, and theranostic strategies to identify and target specific alterations in individual tumors.

Distinct Metabolic Signature of Human Bladder Cancer Cells Carrying an Impaired Fanconi Anemia Tumor-Suppressor Signaling Pathway

Metabolic profiling has great potential to help the diagnosis and prognosis of cancer patients. Fanconi Anemia (FA) tumor-suppressor signaling has been instrumental in understanding human tumorigenesis. However, this instrumental understanding has never been demonstrated at the metabolic level. Here, we show that impaired FA signaling can lead cells to exhibit metabolic signatures of tumorigenesis. This is consistent with our original studies of the roles of FA signaling in suppressing non-FA tumorigenesis at functional and genetic levels. Using ultraperformance liquid chromatography-mass spectroscopy and gas chromatography-mass spectrometry, we characterized metabolic alterations in bladder cancer cells carrying an intact or impaired FA pathway. The latter was obtained by ectopically expressing FAVL (FAVL-high), which we previously found to be capable of inactivating FA signaling. A total of 18 metabolites, end products of cell proliferation or apoptosis, were significantly different between FAVL-high and -low cells. Methionine, phenylalanine, and threonine, resulting from a tumorigenic process, were substantially increased in FAVL-high cells. With this study, we achieved genomic, functional, and metabolomic characterization of the roles of FA signaling in the development of human cancer. Furthermore, this study provides novel insights into how to translate FA basic research into strategies for producing effective biomarkers in human cancer diagnosis and prognosis.

Filtration Device for On-Site Collection, Storage and Shipment of Cells from Urine and Its Application to DNA-Based Detection of Bladder Cancer

Molecular analysis of cells from urine provides a convenient approach to non-invasive detection of bladder cancer. The practical use of urinary cell-based tests is often hampered by difficulties in handling and analyzing large sample volumes, the need for rapid sample processing to avoid degradation of cellular content, and low sensitivity due to a high background of normal cells. We present a filtration device, designed for home or point-of-care use, which enables collection, storage and shipment of urinary cells. A special feature of this device is a removable cartridge housing a membrane filter, which after filtration of urine can be transferred to a storage unit containing an appropriate preserving solution. In spiking experiments, the use of this device provided efficient recovery of bladder cancer cells with elimination of >99% of excess smaller-sized cells. The performance of the device was further evaluated by DNA-based analysis of urinary cells collected from 57 patients subjected to transurethral resection following flexible cystoscopy indicating the presence of a tumor. All samples were tested for FGFR3 mutations and seven DNA methylation markers (BCL2, CCNA1, EOMES, HOXA9, POU4F2, SALL3 and VIM). In the group of patients where a transitional cell tumor was confirmed at histopathological evaluation, urine DNA was positive for one or more markers in 29 out of 31 cases (94%), including 19 with FGFR3 mutation (61%). In the group of patients with benign histopathology, urine DNA was positive for methylation markers in 13 out of 26 cases (50%). Only one patient in this group was positive for a FGFR3 mutation. This patient had a stage Ta tumor resected 6 months later. The ability to easily collect, store and ship diagnostic cells from urine using the presented device may facilitate non-invasive testing for bladder cancer.

Metabonomic profiling of bladder cancer

Early diagnosis and life-long surveillance are clinically important to improve the long-term survival of bladder cancer patients. Currently, a noninvasive biomarker that is as sensitive and specific as cystoscopy in detecting bladder tumors is lacking. Metabonomics is a complementary approach for identifying perturbed metabolic pathways in bladder cancer. Significant progress has been made using modern metabonomic techniques to characterize and distinguish bladder cancer patients from control subjects, identify marker metabolites, and shed insights on the disease biology and potential therapeutic targets. With its rapid development, metabonomics has the potential to impact the clinical management of bladder cancer patients in the future by revolutionizing the diagnosis and life-long surveillance strategies and stratifying patients for diagnostic, surgical, and therapeutic clinical trials. An introduction to metabonomics, typical metabonomic workflow, and critical evaluation of metabonomic investigations in identifying biomarkers for the diagnosis of bladder cancer are presented.

Clinical performance and utility of a DNA methylation urine test for bladder cancer

INTRODUCTION

Abnormal gene methylation has been observed in several cancers. A prior study reported methylation of TWIST1 and NID2 as a quantitative biomarker for urothelial carcinoma, but external validation has yet to be performed. We sought to externally validate a urine-based methylation assay combining TWIST1 and NID2 and assess its clinical utility.

METHODS

A prospective trial was conducted comparing the methylation assay to cystoscopy and biopsy in patients with hematuria or prior non-muscle invasive bladder cancer. Sensitivity, specificity, negative and positive predictive values, and likelihood ratios of the methylation assay were calculated. Area under the receiver operating characteristic curves for each gene and the combined assay were computed. Bayesian analyses were performed to assess utility of the assay for a variety of clinical scenarios.

RESULTS

Complete data were available for 111 patients. In validating the prior assay definition in the current cohort, sensitivity and specificity were 79% and 63%, respectively, and when optimized for the current cohort were 75% and 71%, respectively. The area under the curve for the assay was 0.73 compared with biopsy and 0.71 compared with cystoscopy.

CONCLUSIONS

We failed to replicate the excellent performance of the methylation assay in this external validation; however, this assay may have utility for screening or surveillance for non-muscle invasive bladder cancer.

Peptide-conjugated glass slides for selective capture and purification of diagnostic cells: Applications in urine cytology

Obtaining a clear view of the cells of interest in diagnostic cytology can be challenging when specimens are contaminated with blood or other obscuring cells. In this study, we present a powerful technique for the selective capture of diagnostic epithelial cells directly on a microscope slide, highlighting its applications in urine cytology and immunocytochemistry (ICC). Using phage-display biopanning, we identified and synthesized a series of peptides that bind with high affinity to urothelial cells but not blood cells. We developed methods for conjugating the peptides to glass slides, and we used these slides to selectively capture both normal and cancerous epithelial cells from urine contaminated with blood cells. Unlike non-selective microscope slides, the peptide-conjugated slides selectively retained the cells of interest, recovering up to 75% of urothelial cells, while up to 98% of blood cells were washed away. The slides are compatible with Papanicolaou and hematoxylin and eosin (H&E) staining for cytology preparations, as well as ICC for detecting membrane-associated and nuclear cancer markers. We successfully detected the expression of carcinoembryonic antigen and survivin, two commonly measured bladder cancer markers. In addition to bladder cancer diagnostics, this technology has broad applications for increasing the quality of sample preparations in slide-based diagnostic testing.

Urinary calprotectin: a new diagnostic marker in urothelial carcinoma of the bladder

PURPOSE

Recently, a proteomic study of sera from patients with bladder cancer identified S100A8 and S100A9 as tumor-associated proteins. The present cross-sectional study investigates whether calprotectin, the heterodimer of S100A8/S100A9 may serve as a urinary biomarker for the detection of urothelial bladder cancer.

METHODS

Urinary calprotectin concentrations were assessed in a population of 181 subjects including 46 cases of bladder cancer. 41 cases of renal cell cancer, 54 cases of prostate cancer, and 40 healthy subjects served as control. Acute kidney injury, urinary tract infection, previous BCG-treatment and secondary transurethral resection of the bladder tumor were defined as exclusion criteria. Assessment was performed by enzyme-linked immunosorbent assay and immunohistochemistry detecting calprotectin.

RESULTS

Median calprotectin concentrations (ng/ml) were significantly higher in patients with bladder cancer than in healthy controls (522.3 vs. 51.0, p < 0.001), renal cell cancer (90.4, p < 0.001), and prostate cancer (71.8, p < 0.001). In urothelial carcinoma prominent immunostaining occurred in a subset of tumor cells and in infiltrating myeloid cells. Receiver operating characteristic analysis provided an area under the curve of 0.88 for the differentiation of bladder cancer and healthy control. A cut-off value of 140 ng/ml (determined by Youden's index) resulted in sensitivity and specificity values of 80.4 and 92.5 %. Low grade tumors were associated with significantly lower calprotectin concentrations than high grade tumors (351.9 vs. 1635.2 ng/ml, p = 0.004).

CONCLUSIONS

Urothelial malignancies are associated with highly increased concentrations of calprotecin in the urine. In absence of renal failure and pyuria, calprotectin constitutes a promising biomarker for the detection of bladder cancer.

Low- and high-grade bladder cancer determination via human serum-based metabolomics approach

To address the shortcomings of urine cytology and cystoscopy for probing and grading urinary bladder cancer (BC), we applied (1)H nuclear magnetic resonance (NMR) spectroscopy as a surrogate method for the identification of BC. This study includes 99 serum samples comprising low-grade (LG; n = 36) and high-grade (HG; n = 31) BC as well as healthy controls (HC; n = 32). (1)H NMR-derived serum data were analyzed using orthogonal partial least-squares discriminant analysis (OPLS-DA). OPLS-DA-derived model validity was confirmed using an internal and external cross-validation. Internal validation was performed using the initial samples (n = 99) data set. External validation was performed on a new batch of suspected BC patients (n = 106) through a double-blind study. Receiver operating characteristic (ROC) curve analysis was also performed. OPLS-DA-derived serum metabolomics (six biomarkers, ROC; 0.99) were able to discriminate 95% of BC cases with 96% sensitivity and 94% specificity when compared to HC. Likewise (three biomarkers, ROC; 0.99), 98% of cases of LG were able to differentiate from HG with 97% sensitivity and 99% specificity. External validation reveals comparable results to the internal validation. (1)H NMR-based serum metabolic screening appears to be a promising and less invasive approach for probing and grading BC in contrast to the highly invasive and painful cystoscopic approach for BC detection.

Urinary metabotyping of bladder cancer using two-dimensional gas chromatography time-of-flight mass spectrometry

Cystoscopy is the gold standard clinical diagnosis of human bladder cancer (BC). As cystoscopy is expensive and invasive, it compromises patients' compliance toward surveillance screening and challenges the detection of recurrent BC. Therefore, the development of a noninvasive method for the diagnosis and surveillance of BC and the elucidation of BC progression become pertinent. In this study, urine samples from 38 BC patients and 61 non-BC controls were subjected to urinary metabotyping using two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOFMS). Subsequent to data preprocessing and chemometric analysis, the orthogonal partial least-squares discriminant analysis (OPLS-DA, R2X=0.278, R2Y=0.904 and Q2Y (cumulative)=0.398) model was validated using permutation tests and receiver operating characteristic (ROC) analysis. Marker metabolites were further screened from the OPLS-DA model using statistical tests. GC×GC-TOFMS urinary metabotyping demonstrated 100% specificity and 71% sensitivity in detecting BC, while 100% specificity and 46% sensitivity were observed via cytology. In addition, the model revealed 46 metabolites that characterize human BC. Among the perturbed metabolic pathways, our clinical finding on the alteration of the tryptophan-quinolinic metabolic axis in BC suggested the potential roles of kynurenine in the malignancy and therapy of BC. In conclusion, global urinary metabotyping holds potential for the noninvasive diagnosis and surveillance of BC in clinics. In addition, perturbed metabolic pathways gleaned from urinary metabotyping shed new and established insights on the biology of human BC.

A novel precision-engineered microfiltration device for capture and characterisation of bladder cancer cells in urine

BACKGROUND

Sensitivity of standard urine cytology for detecting urothelial carcinoma of the bladder (UCB) is low, attributable largely to its inability to process entire samples, paucicellularity and presence of background cells.

OBJECTIVE

Evaluate performance and practical applicability of a novel portable microfiltration device for capture, enumeration and characterisation of exfoliated tumour cells in urine, and compare it with standard urine cytology for UCB detection.

METHODS

A total of 54 urine and bladder wash samples from patients undergoing surveillance for UCB were prospectively evaluated by standard and microfilter-based urine cytology. Head-to-head comparison of quality and performance metrics, and cost effectiveness was conducted for both methodologies.

RESULTS

Five samples were paucicellular by standard cytology; no samples processed by microfilter cytology were paucicellular. Standard cytology had 33.3% more samples with background cells that limited evaluation (p<0.001). Microfilter cytology was more concordant (κ=50.4%) than standard cytology (κ=33.5%) with true UCB diagnosis. Sensitivity, specificity and accuracy were higher for microfilter cytology compared to standard cytology (53.3%/100%/79.2% versus 40%/95.8%/69.9%, respectively). Microfilter-captured cells were amenable to downstream on-chip molecular analyses. A 40 ml sample was processed in under 4 min by microfilter cytology compared to 5.5 min by standard cytology. Median microfilter cytology processing and set-up costs were approximately 63% cheaper and 80 times lower than standard cytology, respectively.

CONCLUSIONS

The microfiltration device represents a novel non-invasive UCB detection system that is economical, rapid, versatile and has potentially better quality and performance metrics than routine urine cytology, the current standard-of-care.

Republished: non-invasive urine based tests for the detection of bladder cancer

Bladder cancer is the fourth most frequently diagnosed malignant neoplasm and cause of cancer-related deaths in men and eighth in women. Patients with bladder cancer undergo repeated cystoscopic examinations of the bladder to monitor for tumour recurrence which is invasive, costly and lacks accuracy. Therefore, the development of non-invasive urine based tests for the early detection of bladder cancer would be of tremendous benefit to both patients and healthcare systems. A number of urine based markers are available for the early diagnosis of bladder cancer. The diagnosis of bladder cancer relies on identifying malignant cells in the urine. All urinary markers have a higher sensitivity as compared with cytology but they score lower in specificity. Many soluble and cell based markers have been developed. Only two of the soluble and cell based markers have obtained the Food and Drug Administration approval. In the current review, the most recent literature of urinary markers is summarised. This article reports some of the more prominent urine markers and new technologies used nowadays.

Clinical applications of recent molecular advances in urologic malignancies: no longer chasing a "mirage"?

As our understanding of the molecular events leading to the development and progression of genitourologic malignancies, new markers of detection, prognostication, and therapy prediction can be exploited in the management of these prevalent tumors. The current review discusses the recent advances in prostate, bladder, renal, and testicular neoplasms that are pertinent to the anatomic pathologist.

Proteomic studies of urinary biomarkers for prostate, bladder and kidney cancers

Urine is an ideal body fluid for the detection of protein markers produced by urological cancers as it can be sampled noninvasively and contains secreted and directly shed proteins from the prostate, bladder and kidney. Major challenges of working with urine include high inter-individual and intra-individual variability, low protein concentration, the presence of salts and the dynamic range of protein expression. Despite these challenges, significant progress is being made using modern proteomic methods to identify and characterize protein-based markers for urological cancers. The development of robust, easy-to-use clinical tests based on novel biomarkers has the potential to impact upon diagnosis, prognosis and monitoring and could revolutionize the treatment and management of these cancers.

Prognostic value of cell-cycle regulation biomarkers in bladder cancer

The determination of prognosis in bladder cancer is currently based on staging methods that rely primarily on the pathological stage of a tumor with limited objective correlates. The development and progression of bladder cancer involve alterations in several cellular pathways. Dysregulation in markers associated with cell-cycle regulation has been the most extensively examined molecular aberration in this cancer. Individual alterations of these markers have been associated with disease outcome, with several observations suggesting that their prognostic potential is independent of pathological stage. While many individual molecules in the cell growth receptor signaling, p53, and retinoblastoma (Rb) pathways have been identified, there is a general lack of consensus on which markers can be adopted in the clinical setting. More recent studies have suggested that the combination of markers as concise panels may be more beneficial in determining the degree of aggressiveness of a given tumor and its impending outcome than individual markers alone. This review will discuss alterations in molecules within pathways controlling cell-cycle regulation in the context of bladder cancer, and their impact on patient outcome when examined individually and in combination.

Molecular Pathology of Bladder Cancer

This article focuses on several promising candidate biomarkers that may soon make their transition to the realm of clinical management of bladder cancer. Presented are superficial and muscle-invasive urothelial carcinoma of the bladder and the genetic tests currently available in testing for diagnosis and prognosis of these diseases.

Urine telomerase for diagnosis and surveillance of bladder cancer

Bladder cancer has increased incidence during last decades. For those patients with nonmuscle involved tumors, noninvasive diagnosis test and surveillance methods must be designed to avoid current cystoscopies that nowadays are done regularly in a lot of patients. Novel urine biomarkers have been developed during last years. Telomerase is important in cancer biology, improving the division capacity of cancer cells. Even urinary telomerase could be a potentially useful urinary tumor marker; its use for diagnosis of asymptomatic and symptomatic patients or its impact during surveillance is still unknown. Moreover, there will need to be uniformity and standardization in the assays before it can become useful in clinical practice. It does not seem to exist a real difference between the most classical assays for the detection of urine telomerase (TRAP and hTERT). However, the new detection methods with modified TeloTAGGG telomerase or with gold nanoparticles must also be taken into consideration for the correct development of this diagnosis method. Maybe the target population would be the high-risk groups within screening programs. To date there is no enough evidence to use it alone and to eliminate cystoscopies from the diagnosis and surveillance of these patients. The combination with cytology or FISH is still preferred.

Non-invasive urine based tests for the detection of bladder cancer

Bladder cancer is the fourth most frequently diagnosed malignant neoplasm and cause of cancer-related deaths in men and eighth in women. Patients with bladder cancer undergo repeated cystoscopic examinations of the bladder to monitor for tumour recurrence which is invasive, costly and lacks accuracy. Therefore, the development of non-invasive urine based tests for the early detection of bladder cancer would be of tremendous benefit to both patients and healthcare systems. A number of urine based markers are available for the early diagnosis of bladder cancer. The diagnosis of bladder cancer relies on identifying malignant cells in the urine. All urinary markers have a higher sensitivity as compared with cytology but they score lower in specificity. Many soluble and cell based markers have been developed. Only two of the soluble and cell based markers have obtained the Food and Drug Administration approval. In the current review, the most recent literature of urinary markers is summarised. This article reports some of the more prominent urine markers and new technologies used nowadays.

Emerging critical role of molecular testing in diagnostic genitourinary pathology

CONTEXT

The unprecedented advances in cancer genetics and genomics are rapidly affecting clinical management and diagnostics in solid tumor oncology. Molecular diagnostics is now an integral part of routine clinical management in patients with lung, colon, and breast cancer. In sharp contrast, molecular biomarkers have been largely excluded from current management algorithms of urologic malignancies.

OBJECTIVE

To discuss promising candidate biomarkers that may soon make their transition to the realm of clinical management of genitourologic malignancies. The need for new treatment alternatives that can improve upon the modest outcome so far in patients with several types of urologic cancer is evident. Well-validated prognostic molecular biomarkers that can help clinicians identify patients in need of early aggressive management are lacking. Identifying robust predictive biomarkers that will stratify response to emerging targeted therapeutics is another crucially needed development. A compiled review of salient studies addressing the topic could be helpful in focusing future efforts.

DATA SOURCES

A PubMed (US National Library of Medicine) search for published studies with the following search terms was conducted: molecular , prognostic , targeted therapy , genomics , theranostics and urinary bladder cancer , prostate adenocarcinoma , and renal cell carcinoma . Articles with large cohorts and multivariate analyses were given preference.

CONCLUSIONS

Our recent understanding of the complex molecular alterations involved in the development and progression of urologic malignancies is yielding novel diagnostic and prognostic molecular tools and opening the doors for experimental targeted therapies for these prevalent, frequently lethal solid tumors.

Long interspersed nuclear element-1 hypomethylation and oxidative stress: correlation and bladder cancer diagnostic potential

Although, increased oxidative stress and hypomethylation of long interspersed nuclear element-1 (LINE-1) associate with bladder cancer (BCa) development, the relationship between these alterations is unknown. We evaluated the oxidative stress and hypomethylation of the LINE-1 in 61 BCa patients and 45 normal individuals. To measure the methylation levels and to differentiate the LINE-1 loci into hypermethylated, partially methylated and hypomethylated, peripheral blood cells, urinary exfoliated cells and cancerous tissues were evaluated by combined bisulfite restriction analysis PCR. The urinary total antioxidant status (TAS) and plasma protein carbonyl content were determined. The LINE-1 methylation levels and patterns, especially hypomethylated loci, in the blood and urine cells of the BCa patients were different from the levels and patterns in the healthy controls. The urinary TAS was decreased, whereas the plasma protein carbonyl content was increased in the BCa patients relative to the controls. A positive correlation between the methylation of LINE-1 in the blood-derived DNA and urinary TAS was found in both the BCa and control groups. The urinary hypomethylated LINE-1 loci and the plasma protein carbonyl content provided the best diagnostic potential for BCa prediction. Based on post-diagnostic samples, the combination test improved the diagnostic power to a sensitivity of 96% and a specificity of 96%. In conclusion, decreased LINE-1 methylation is associated with increased oxidative stress both in healthy and BCa subjects across the various tissue types, implying a dose-response association. Increases in the LINE-1 hypomethylation levels and the number of hypomethylated loci in both the blood- and urine-derived cells and increase in the oxidative stress were found in the BCa patients. The combination test of the urinary hypomethylated LINE-1 loci and the plasma protein carbonyl content may be useful for BCa screening and monitoring of treatment.