Usefulness of the BTA STAT Test for the diagnosis of bladder cancer

Noninvasive Urine-Based Tests to Diagnose or Detect Recurrence of Bladder Cancer

Liquid biopsies are increasingly used for the diagnosis and follow-up of cancer patients. Urine is a body fluid that can be used to detect cancers and others diseases. It is noninvasive and easy to collect. To detect Bladder Cancer (BC), cytology is the first assay used. It is an effective way to detect high grade BC but has a high rate of equivocal results, especially for low grade BC. Furthermore, cystoscopy is used to confirm cytology results and to determine cancer status. Cystoscopy is also effective but highly invasive, and not well accepted by patients, especially for BC follow-up. In this review we survey the numerous assays recently developed in order to diagnose BC at an early stage, and to facilitate the follow-up of patients. We discuss their effectiveness, ease of use, and applications. Finally, we discuss assays that, in the future, could improve the diagnosis and management of BC patients.

Review of non-invasive urinary biomarkers in bladder cancer

Bladder cancer (BC) is the sixth-most prevalent cancer. The standard diagnostic tool of BC is cystoscopy, whereas cystoscopy has several disadvantages in terms of symptomatic invasiveness and operator-dependency. The urinary markers are attractive because the testing is non-invasive and cost-efficient, and sample collection is easy. Urinary marker is thereby a good tool to detect exfoliated tumor cell in the urine samples for the diagnosis and therapeutic surveillance of BC to supplement the limitations of the cystoscopy. However, they are not recommended as a population-based screening tool because of the low rate of BC prevalence. Although both cystoscopy and urine cytology improve BC diagnostic power, the field still needs additional non-invasive, cost-effective, and highly sensitive and specific diagnostic tools. Various urinary markers with different mechanisms and different targets have been developed and under investigation in these days. However, the accuracy of the urinary marker including its sensitivity and specificity is the most important factor for the diagnosis and surveillance in cancer that this review deals with multiple FDA-approved and non-FDA approved commercialized urinary markers with their accuracy in different purposes for BC. We then discuss more about the potential candidate targets for the future urinary markers in BC.

Urine biopsy technologies: Cancer and beyond

Since the discovery of circulating tumor cells in 1869, technological advances in the study of biomarkers from liquid biopsy have made it possible to diagnose disease in a less invasive way. Although blood-based liquid biopsy has been used extensively for the detection of solid tumors and immune diseases, the potential of urine-based liquid biopsy has not been fully explored. Advancements in technologies for the harvesting and analysis of biomarkers are providing new opportunities for the characterization of other disease types. Liquid biopsy markers such as exfoliated bladder cancer cells, cell-free DNA (cfDNA), and exosomes have the potential to change the nature of disease management and care, as they allow a cost-effective and convenient mode of patient monitoring throughout treatment. In this review, we addressed the advancement of research in the field of disease detection for the key liquid biopsy markers such as cancer cells, cfDNA, and exosomes, with an emphasis on urine-based liquid biopsy. First, we highlighted key technologies that were widely available and used extensively for clinical urine sample analysis. Next, we presented recent technological developments in cell and genetic research, with implications for the detection of other types of diseases, besides cancer. We then concluded with some discussions on these areas, emphasizing the role of microfluidics and artificial intelligence in advancing point-of-care applications. We believe that the benefits of urine biopsy provide diagnostic development potential, which will pave opportunities for new ways to guide treatment selections and facilitate precision disease therapies.

Biomarkers for Bladder Cancer Diagnosis and Surveillance: A Comprehensive Review

Bladder cancer (BC) ranks as the sixth most prevalent cancer in the world, with a steady rise in its incidence and prevalence, and is accompanied by a high morbidity and mortality. BC is a complex disease with several molecular and pathological pathways, thus reflecting different behaviors depending on the clinical staging of the tumor and molecular type. Diagnosis and monitoring of BC is mainly performed by invasive tests, namely periodic cystoscopies; this procedure, although a reliable method, is highly uncomfortable for the patient and it is not exempt of comorbidities. Currently, there is no formal indication for the use of molecular biomarkers in clinical practice, even though there are several tests available. There is an imperative need for a clinical non-invasive testing for early detection, disease monitoring, and treatment response in BC. In this review, we aim to assess and compare different tests based on molecular biomarkers and evaluate their potential role as new molecules for bladder cancer diagnosis, follow-up, and treatment response monitoring.

Unbiased enrichment of urine exfoliated cells on nanostructured substrates for sensitive detection of urothelial tumor cells

Background

Early detection of urothelial carcinoma (UC) by noninvasive diagnostic methods with high accuracy is still underscored. This study aimed to develop a noninvasive assay incorporating both enrichment of urine exfoliated cells and immunoassays for UC detection.

Methods

Polystyrene dishes were exposed to oxygen plasma and modified with 3‐aminopropyltriethoxysilane to prepare amine‐functionalized nanostructured substrates (NS). Performance characterization of NS was evaluated by atomic force microscope and X‐ray photoelectron spectroscopy. Urine exfoliated cells were captured by NS and then immunostained to detect urinary tumor cells (UTCs), which was called UTC assay. The receiver operating characteristic (ROC) curve, area under ROC curve (AUC), and Youden index were used to find the cutoff value of UTC assay. ROC analysis and McNemar test were used to compare the diagnostic accuracy of UTC assay with cytology. Kappa test was used to analyze the agreement of UTC assay and cytology with pathological diagnosis.

Results

Nanostructured substrates had good cell binding yields of nucleated cells and tumor cells. CK20⁺CD45⁻CD11b⁻ cells were considered as UTCs. UTC number ≥ 1 per sample could be considered as a positive result. By AUC and Kappa analysis, UTC assay showed good performance in UC detection. McNemar test demonstrated that UTC assay had a superior sensitivity even in low‐grade subgroup and a similar specificity compared to cytology in UC diagnosis.

Conclusions

Nanostructured substrates could be used to enrich the exfoliated cells from urine samples. UTC assay with NS has the potential to play a role in UC detection. The value of this assay still needs additional validation by large, multi‐center studies.

Bladder Tumor Markers: A Review of the Literature

Bladder cancer is among the top eight most frequent cancers. Its natural history is related to a combination of factors that impact on its aggressiveness. Cystoscopy and urine cytology are the currently used techniques for the diagnosis and surveillance of non-invasive bladder tumors. The sensitivity of urine cytology for diagnosis is not high, particularly in low-grade tumors. The combination of voided urine cytology and new diagnostic urine tests would be ideal for the diagnosis and follow-up of bladder cancer. However, in order to have some clinical utility, new diagnostic and/or prognostic markers should achieve better predictive capacity that the currently used diagnostic tools. None of the markers evaluated over the last years showed remarkable sensitivity or specificity for the identification of any of the diverse types of bladder cancer in clinical practice. The limitations of the known prognostic markers have led to the research of new molecular markers for early detection of bladder cancer. This research focused in particular on the discovery of biomarkers capable of reducing the need for periodic cystoscopies or, ideally, offering a non-invasive examination instead. In this review, we will examine various new markers of bladder cancer and their value in the diagnosis and follow-up of non-muscle-invasive bladder cancer. When compared with urine cytology, which showed the highest specificity, most of these markers demonstrated an increased sensitivity.

Spectrophotometric photodynamic detection involving extracorporeal treatment with hexaminolevulinate for bladder cancer cells in voided urine

PURPOSE

To evaluate the feasibility of hexaminolevulinate (HAL) for the photodynamic detection of cancer cells in voided urine.

METHODS

This study included 50 patients with bladder cancer that was confirmed histologically after transurethral resection (bladder cancer group) and 50 outpatients without a history of urothelial carcinoma or cancer-related findings (no malignancy group). One third of the voided urine samples were incubated with aminolevulinic acid (ALA-treated samples), one third were incubated with HAL (HAL-treated samples), and the remaining samples were incubated without treatment (untreated samples). For detecting cellular protoporphyrin IX levels, the intensity of the samples at the excitation wavelength of 405 nm was measured using a spectrophotometer. The difference between the intensity of the ALA-treated or HAL-treated samples and the untreated samples at 635 nm was calculated.

RESULTS

HAL-induced fluorescence cytology (HFC) showed that the difference was significantly higher in patients with high-grade tumors than in those with low-grade tumors (p = 0.0003) and the difference was significantly higher in patients with low-grade tumors than in those without a history of urothelial carcinoma or cancer-related findings (p = 0.021). The areas under the receiver operating characteristic curves of ALA-induced fluorescence cytology (AFC) and HFC were 0.77 and 0.81, respectively. The AUC of HFC was significantly higher than that of AFC (p < 0.0001). The overall sensitivity values for conventional cytology, AFC, and HFC were 49, 74, and 74%, respectively. The overall specificity values for AFC and HFC were 70 and 94%, respectively.

CONCLUSIONS

Spectrophotometric photodynamic detection involving extracorporeal treatment with HAL for bladder cancer cells in voided urine showed high accuracy. This bladder cancer detection method is easy and cost-effective, and has the potential for clinical use.

Molecular and Functional Diagnostic Tools in Precision Oncology for Urological Malignancies

Urological malignancies, represented mainly by prostate, bladder, and renal cancers, are some of the leading causes of cancer-related mortalities worldwide. Despite various efforts over decades to develop early detection tests and effective therapeutic paradigms, the response rate to the existing treatments remains low for both primary and late stage/recurrent phases of these cancers. The evolving landscape of molecular diagnostics, aiming to make the diagnosis and treatment more patient-driven, underpins precision oncology and particularly intends to rationally profile individual tumors and highlight the mechanistic insight and complexity of tumor microenvironment in order to develop biomarkers of toxicity risks and response prediction in a clinically oriented dynamical setting. The present review is an effort to capture some of the recent developments in the area of molecular diagnostics and functional testing platforms and their potential application in clinical decision making in the premises of precision oncology of urological malignancies.

Elevated preoperative plasma fibrinogen level is an independent predictor of malignancy and advanced stage disease in patients with bladder urothelial tumors

PURPOSE

To investigate the association between preoperative plasma fibrinogen levels and clinicopathological features in patients with bladder urothelial tumors.

METHODS

In this retrospective single-center study, we evaluated preoperative plasma fibrinogen levels in 503 patients newly diagnosed with bladder urothelial tumors between January 2009 and October 2014. All patients received surgical intervention as the primary treatment method. Associations between preoperative plasma fibrinogen levels and clinicopathological parameters were analyzed. Univariate and multivariate logistic regression analyses were performed to identify independent associations.

RESULTS

The mean preoperative fibrinogen level in patients with bladder urothelial carcinoma (BUC) was significantly higher than that in patients with papilloma or papillary urothelial neoplasm of low malignant potential (PUNLMP) (P = 0.004). Additionally, patients with BUC with advanced-stage disease showed elevated plasma fibrinogen levels compared to patients with early-stage disease (high-grade BUC vs. low-grade BUC: P = 0.002; muscle-invasive BUC vs. non-muscle-invasive BUC: P = 0.010). In a multivariate regression model, a plasma fibrinogen level >3.04 g/L was identified to be independently associated with the presence of BUC (hazard ratio [HR] = 1.653, P = 0.047), high-grade BUC (HR = 1.869, P = 0.004), and muscle-invasive BUC (HR = 1.870, P = 0.044).

CONCLUSIONS

Elevated preoperative plasma fibrinogen level is an independent predictor of malignancy as well as advanced-stage carcinoma in patients with bladder urothelial tumors, suggesting that plasma fibrinogen may be a promising diagnostic and prognostic biomarker for bladder tumors.

Highly sensitive and specific novel biomarkers for the diagnosis of transitional bladder carcinoma

Transitional bladder carcinoma (BCa) is prevalent in developed countries, particularly among men. Given that these tumors frequently recur or progress, the early detection and subsequent monitoring of BCa at different stages is critical. Current BCa diagnostic biomarkers are not sufficiently sensitive for substituting or complementing invasive cystoscopy. Here, we sought to identify a robust set of urine biomarkers for BCa detection. Using a high-resolution, mass spectrometry-based, quantitative proteomics approach, we measured, compared and validated protein variations in 451 voided urine samples from healthy subjects, non-bladder cancer patients and patients with non-invasive and invasive BCa. We identified five robust biomarkers: Coronin-1A, Apolipoprotein A4, Semenogelin-2, Gamma synuclein and DJ-1/PARK7. In diagnosing Ta/T1 BCa, these biomarkers achieved an AUC of 0.92 and 0.98, respectively, using ELISA and western blot data (sensitivity, 79.2% and 93.9%; specificity, 100% and 96.7%, respectively). In diagnosing T2/T3 BCa, an AUC of 0.94 and 1.0 was attained (sensitivity, 86.4% and 100%; specificity, 100%) using the same methods. Thus, our multiplex biomarker panel offers unprecedented accuracy for the diagnosis of BCa patients and provides the prospect for a non-invasive way to detect bladder cancer.

Biomarkers for non-muscle invasive bladder cancer: Current tests and future promise

The search continues for optimal markers that can be utilized to improve bladder cancer detection and to predict disease recurrence. Although no single marker has yet replaced the need to perform cystoscopy and urine cytology, many tests have been evaluated and are being developed. In the future, these promising markers may be incorporated into standard practice to address the challenge of screening in addition to long-term surveillance of patients who have or are at risk for developing bladder cancer.

Urinary biomarkers of bladder cancer: an update and future perspectives

Bladder cancer is one of the most prevalent cancers worldwide. Early detection of bladder tumors is critical for improved patient outcomes. The standard method for detection and surveillance of bladder tumors is cystoscopy with urinary cytology. Limitations of cystoscopy and urinary cytology have brought to light the need for more robust diagnostic assays. Ideally, such assays would be applicable to noninvasively obtained, voided urine, and be designed not only for diagnosis, but also for monitoring disease recurrence and response to therapy. Consequently, the development of a noninvasive urine-based assay would be of tremendous benefit to both patients and healthcare systems. This article reports some of the more prominent urine-based biomarkers reported in the literature. In addition, some new technologies that have been used to identify novel urinary biomarkers are highlighted.

Bladder cancer detection and monitoring: assessment of urine- and blood-based marker tests

Bladder cancer is one of the most prevalent cancers worldwide, but the treatment and management of this disease can be very successful if the disease is detected early. The development of molecular assays that could diagnose bladder cancer accurately, and at an early stage, would be a significant advance. Ideally, such molecular assays would be applicable to non-invasively obtained body fluids, and be designed not only for diagnosis but also for monitoring disease recurrence and response to treatment. In this article, we assess the performance of current diagnostic assays for bladder cancer and discuss some of the emerging biomarkers that could be developed to augment current bladder cancer detection strategies.

Detection of microRNAs in archival cytology urine smears

MicroRNAs’ dysregulation and profiling have been demonstrated to be clinically relevant in urothelial carcinoma (UC). Urine cytology is commonly used as the mainstay non-invasive test for secondary prevention and follow-up of UC patients. Ancillary tools are needed to support cytopathologists in the diagnosis of low-grade UC. The feasibility and reliability of microRNAs profiling by qRT-PCR analysis (miR-145 and miR-205) in archival routine urine cytology smears (affected by fixation/staining [Papanicolau] and room temperature storage) was tested in a series of 15 non-neoplastic and 10 UC urine specimens. Only samples with >5,000 urothelial cells and with <50% of inflammatory cells/red blood cells clusters were considered. Overall, a satisfactory amount of total RNA was obtained from all the considered samples (mean 1.27±1.43 µg, range 0.06–4.60 µg). Twenty nanograms of total RNA have been calculated to be the minimal total RNA concentration for reliable and reproducible miRNAs expression profiling analysis of archival cytological smears (slope = -3.4084; R-squared = 0.99; efficiency = 1.94). miR-145 and miR-205 were significantly downregulated in UC samples in comparison to non-tumor controls. These findings demonstrate that urine archival cytology smears are suitable for obtaining high-quality RNA to be used in microRNAs expression profiling. Further studies should investigate if miRNAs profiling can be successfully translated into clinical practice as diagnostic or prognostic markers.

Molecular diagnostic trends in urological cancer: biomarkers for non-invasive diagnosis

The early detection of urological cancers is pivotal for successful patient treatment and management. The development of molecular assays that can diagnose disease accurately, or that can augment current methods of evaluation, would be a significant advance. Ideally, such molecular assays would be applicable to non-invasively obtained body fluids, enabling not only diagnosis of at risk patients, but also asymptomatic screening, monitoring disease recurrence and response to treatment. The advent of advanced proteomics and genomics technologies and associated bioinformatics development is bringing these goals into focus. In this article we will discuss the promise of biomarkers in urinalysis for the detection and clinical evaluation of the major urological cancers, including bladder, kidney and prostate. The development of urine-based tests to detect urological cancers would be of tremendous benefit to both patients and the healthcare system.

A candidate molecular biomarker panel for the detection of bladder cancer

BACKGROUND

Bladder cancer is among the five most common malignancies worldwide, and due to high rates of recurrence, one of the most prevalent. Improvements in noninvasive urine-based assays to detect bladder cancer would benefit both patients and health care systems. In this study, the goal was to identify urothelial cell transcriptomic signatures associated with bladder cancer.

METHODS

Gene expression profiling (Affymetrix U133 Plus 2.0 arrays) was applied to exfoliated urothelia obtained from a cohort of 92 subjects with known bladder disease status. Computational analyses identified candidate biomarkers of bladder cancer and an optimal predictive model was derived. Selected targets from the profiling analyses were monitored in an independent cohort of 81 subjects using quantitative real-time PCR (RT-PCR).

RESULTS

Transcriptome profiling data analysis identified 52 genes associated with bladder cancer (P ≤ 0.001) and gene models that optimally predicted class label were derived. RT-PCR analysis of 48 selected targets in an independent cohort identified a 14-gene diagnostic signature that predicted the presence of bladder cancer with high accuracy.

CONCLUSIONS

Exfoliated urothelia sampling provides a robust analyte for the evaluation of patients with suspected bladder cancer. The refinement and validation of the multigene urothelial cell signatures identified in this preliminary study may lead to accurate, noninvasive assays for the detection of bladder cancer.

IMPACT

The development of an accurate, noninvasive bladder cancer detection assay would benefit both the patient and health care systems through better detection, monitoring, and control of disease.

Diagnostic potential of urinary α1-antitrypsin and apolipoprotein E in the detection of bladder cancer

PURPOSE

The ability to reliably diagnose bladder cancer in voided urine samples would be a major advance. Using high throughput technologies, we identified a panel of bladder cancer associated biomarkers with potential clinical usefulness. In this study we tested 4 potential biomarkers for the noninvasive detection of bladder cancer.

MATERIALS AND METHODS

We examined voided urine specimens from 124 patients, including 63 newly diagnosed with bladder cancer and 61 controls. Concentrations of proteins were assessed by enzyme-linked immunosorbent assay, including α1-antitrypsin, apolipoprotein E, osteopontin and pentraxin 3. Data were compared to the results of urinary cytology and the BTA Trak® enzyme-linked immunosorbent assay based bladder cancer detection assay. We used the AUC of ROC curves to compare the usefulness of each biomarker to detect bladder cancer.

RESULTS

Urinary levels of α1-antitrypsin, apolipoprotein E and bladder tumor antigen were significantly increased in subjects with bladder cancer. α1-Antitrypsin (AUC 0.9087, 95% CI 0.8555-0.9619) and apolipoprotein E (AUC 0.8987, 95% CI 0.8449-0.9525) were the most accurate biomarkers. The combination of α1-antitrypsin and apolipoprotein E (AUC 0.9399) achieved 91% sensitivity, 89% specificity, and a positive and negative predictive value of 89% and 90%, respectively. Multivariate regression analysis highlighted only apolipoprotein E as an independent predictor of bladder cancer (OR 24.9, 95% CI 4.22-146.7, p = 0.0004).

CONCLUSIONS

Alone or in combination, α1-antitrypsin and apolipoprotein E show promise for the noninvasive detection of bladder cancer (OR 24.9, 95% CI 4.22-146.7, p = 0.0004). Larger, prospective studies including more low grade, low stage tumors are needed to confirm these results.

A multi-analyte assay for the non-invasive detection of bladder cancer

Accurate urinary assays for bladder cancer (BCa) detection would benefit both patients and healthcare systems. Through genomic and proteomic profiling of urine components, we have previously identified a panel of biomarkers that can outperform current urine-based biomarkers for the non-invasive detection of BCa. Herein, we report the diagnostic utility of various multivariate combinations of these biomarkers. We performed a case-controlled validation study in which voided urines from 127 patients (64 tumor bearing subjects) were analyzed. The urinary concentrations of 14 biomarkers (IL-8, MMP-9, MMP-10, SDC1, CCL18, PAI-1, CD44, VEGF, ANG, CA9, A1AT, OPN, PTX3, and APOE) were assessed by enzyme-linked immunosorbent assay (ELISA). Diagnostic performance of each biomarker and multivariate models were compared using receiver operating characteristic curves and the chi-square test. An 8-biomarker model achieved the most accurate BCa diagnosis (sensitivity 92%, specificity 97%), but a combination of 3 of the 8 biomarkers (IL-8, VEGF, and APOE) was also highly accurate (sensitivity 90%, specificity 97%). For comparison, the commercial BTA-Trak ELISA test achieved a sensitivity of 79% and a specificity of 83%, and voided urine cytology detected only 33% of BCa cases in the same cohort. These datashow that a multivariate urine-based assay can markedly improve the accuracy of non-invasive BCa detection. Further validation studies are under way to investigate the clinical utility of this panel of biomarkers for BCa diagnosis and disease monitoring.

CCL18 in a multiplex urine-based assay for the detection of bladder cancer

The early detection of bladder cancer (BCa) is pivotal for successful patient treatment and management. Through genomic and proteomic studies, we have identified a number of bladder cancer-associated biomarkers that have potential clinical utility. In a case-control study, we examined voided urines from 127 subjects: 64 tumor-bearing subjects and 63 controls. The urine concentrations of the following proteins were assessed by enzyme-linked immunosorbent assay (ELISA); C-C motif chemokine 18 (CCL18), Plasminogen Activator Inhibitor 1 (PAI-1) and CD44. Data were compared to a commercial ELISA-based BCa detection assay (BTA-Trak©) and voided urinary cytology. We used analysis of the area under the curve of receiver operating characteristic curves to compare the ability of CCL18, PAI-1, CD44, and BTA to detect BCa in voided urine samples. Urinary concentrations of CCL18, PAI-1, and BTA were significantly elevated in subjects with BCa. CCL18 was the most accurate biomarker (AUC; 0.919; 95% confidence interval [CI], 0.8704-0.9674). Multivariate regression analysis highlighted CCL18 (OR; 18.31; 95% CI, 4.95-67.70, p<0.0001) and BTA (OR; 6.43; 95% CI, 1.86-22.21, p = 0.0033) as independent predictors of BCa in voided urine samples. The combination of CCL18, PAI-1 and CD44 improved the area under the curve to0.938. Preliminary results indicate that CCL18 was a highly accurate biomarker for BCa detection in this cohort. Monitoring CCL18 in voided urine samples has the potential to improve non-invasive tests for BCa diagnosis. Furthermore using the combination of CCL18, PAI-1 and CD44 may make the model more robust to errors to detect BCa over the individual biomarkers or BTA.

Evaluation of acridine orange fluorescence in exfoliative urinary cytology for diagnosing bladder carcinoma

PURPOSE

This study reviewed acridine orange fluorescence (AO-F) in exfoliative urinary cytology results of 1,016 inpatients with urothelial cell carcinoma of the bladder and 804 outpatients to investigate the value of AO-F in the diagnosis of bladder cancer.

METHODS

A total of 1,016 bladder cancer inpatients from October 1995 to October 2005 and 804 outpatients from January 2004 to January 2006 were enrolled in this study. Each patient provided the morning urine specimen of 30-50 ml in a sterile container. Urine sediments were stained by acridine orange and observed with a fluorescence microscope; 60 bladder cancer inpatients from January 2006 to July 2007 were also chosen for the control study of three different detection methods, including AO-F, hematoxylin and eosin and Feulgen staining.

RESULTS

Of the 1,016 bladder carcinoma samples analyzed, 793 were AO-F positive. Total positive rate of AO-F was 78.05 %. The positive rate was 74.69 % (611/818) for non-muscle invasive bladder carcinoma and 91.91 % (182/198) for muscle invasive bladder carcinoma. A significant correlation of AO-F positivity with clinical stage was observed (P < 0.01). The positive rates among various pathological grades were 66.7 % (32/48) for G1, 67.5 % (319/474) for G2 and 90.4 % (413/457) for G3 with significant differences (P < 0.01). For the 804 outpatients, the sensitivity and specificity of bladder carcinoma were 77.11 and 85.29 %, respectively.

CONCLUSIONS

With its high sensitivity and specificity, AO-F is superior to other detection methods for bladder carcinoma detection. In addition, it is familiar, non-invasive, quick, cheap and easily repeatable.

Urinary glycoprotein biomarker discovery for bladder cancer detection using LC/MS-MS and label-free quantification

BACKGROUND

Cancers of the urinary bladder are the fifth most commonly diagnosed malignancy in the United States. Early clinical diagnosis of bladder cancer remains a major challenge, and the development of noninvasive methods for detection and surveillance is desirable for both patients and health care providers.

APPROACH

To identify urinary proteins with potential clinical utility, we enriched and profiled the glycoprotein component of urine samples by using a dual-lectin affinity chromatography and liquid chromatography/tandem mass spectrometry platform.

RESULTS

From a primary sample set obtained from 54 cancer patients and 46 controls, a total of 265 distinct glycoproteins were identified with high confidence, and changes in glycoprotein abundance between groups were quantified by a label-free spectral counting method. Validation of candidate biomarker alpha-1-antitrypsin (A1AT) for disease association was done on an independent set of 70 samples (35 cancer cases) by using an ELISA. Increased levels of urinary A1AT glycoprotein were indicative of the presence of bladder cancer (P < 0.0001) and augmented voided urine cytology results. A1AT detection classified bladder cancer patients with a sensitivity of 74% and specificity of 80%.

SUMMARY

The described strategy can enable higher resolution profiling of the proteome in biological fluids by reducing complexity. Application of glycoprotein enrichment provided novel candidates for further investigation as biomarkers for the noninvasive detection of bladder cancer.

Diagnosis of urothelial carcinoma from urine

Urine cytology is the most widely used noninvasive test to detect urothelial tumors. However, it is limited by its low sensitivity. On the other hand, cystoscopy is the gold standard procedure to follow patients with a history of bladder cancer but this test is invasive and costly. Therefore, there is a real need to develop new tests that can be used in bladder cancer surveillance. Several soluble and cell-based markers have been developed and most of them improve the sensitivity of cytology but the specificity is invariably decreased. Of the cell-based tests, two obtained Food and Drug Administration approval. ImmunoCyt/uCyt is a fluorescent test that uses three monoclonal antibodies and UroVysion is an in situ hybridization test, which uses four different probes to different chromosomes. Both tests have a high sensitivity to detect cancer cells and can help to predict urothelial cancer recurrence. ImmunoCyt/uCyt is somewhat better at detecting low-grade tumors but UroVysion is not affected by prior BCG treatment. However, both tests use fluorescent dyes, are time-consuming and require trained personnel. Because of their high negative predictive value, both tests may help the urologist to postpone a number of cystoscopies, especially in patients with low-risk urothelial cancer.

Proteomic strategies in bladder cancer: From tissue to fluid and back

We have applied protein expression profiling technologies in combination with immunohistochemistry, using fresh tissue and urine samples, to assess bladder cancer heterogeneity and prognosis as well as to generate protein markers for tumor progression and early diagnosis of the disease. Here, we review some selected lines of investigation and approaches undertaken by our laboratory, drawing on more than 15 years of experience in bladder cancer proteomics, to highlight a number of issues that may be useful for researchers entering the field. In particular, we address the identification of markers for bladder cancer progression and exemplify the potential of gel-based proteomic profiling of urine samples for the early detection of urothelial carcinomas. In addition, we provide a brief description of a novel and highly promising source of biomarkers, the tumor interstitial fluid (TIF) that perfuses the tumor microenvironment.

Bladder tumor markers beyond cytology: International Consensus Panel on bladder tumor markers

This is the first of 2 articles that summarize the findings of the International Consensus Panel on cytology and bladder tumor markers. The objectives of our panel were to reach a consensus on the areas where markers are needed, to define the attributes of an ideal tumor marker, and to identify which marker(s) would be suitable for diagnosis and/or surveillance of bladder cancer. Our panel consisted of urologists and researchers from Europe, Asia, and the United States who reviewed original articles, reviews, and book chapters on individual bladder tumor markers published in the English language mainly using the PubMed search engine. Panel members also met during 3 international meetings to write recommendations regarding bladder tumor markers. The panel found that the most practical use of noninvasive tests is to monitor bladder cancer recurrence, thereby reducing the number of surveillance cystoscopies performed each year. Markers also may be useful in the screening of high-risk individuals for early detection of bladder cancer. However, more prospective studies are needed to strengthen this argument. Case-control and cohort studies show that several markers have a higher sensitivity to detect bladder cancer. However, cytology is the superior marker in terms of specificity, although some markers in limited numbers of studies have shown specificity equivalent to that of cytology. Our panel believes that several bladder tumor markers are more accurate in detecting bladder cancer than prostate-specific antigen (PSA) is in detecting prostate cancer. However, bladder tumor markers are held to a higher standard than PSA. Therefore, use of bladder tumor markers in the management of patients with bladder cancer will require the willingness of both urologists and clinicians to accept them.

Non-invasive diagnostic tests for bladder cancer: a review of the literature

Transitional cell carcinoma of the bladder is the second most common malignancy of the genitourinary tract. Cystoscopy and urine cytology are the traditional most used techniques for diagnosis and surveillance of superficial bladder cancer. Urine cytology is specific for diagnosis of bladder cancer but sensitivity results not high, particularly in low-grade disease. Voided urine can be easily obtained and therefore additional diagnostic urine tests would be ideal for screening or follow-up of transitional cell carcinoma. A number of studies have focused on the evaluation of urinary markers that hold promise as non-invasive adjuncts to conventional diagnostic or surveillance techniques. In this review we discuss several new urinary markers (test for bladder tumor antigen, NMP22, fibrin degradation products, telomerase, fluorescence in situ hybridization test, flow cytometry) and their role in detection and follow-up of bladder cancer. Most of these markers have higher sensitivity than urine cytology, but voided urine cytology has the highest specificity.

ImmunoCyt/uCyt+ improves the sensitivity of urine cytology in patients followed for urothelial carcinoma

ImmunoCyt/uCyt is a fluorescent test combining three monoclonal antibodies. In this study, it has been tested as a complement to cytology in the detection of urothelial carcinoma in urine. It has been performed simultaneously with standard cytology and cystoscopy on 870 urine analyses from one hospital. In 136 cases, one or more bladder tumors were found. Overall sensitivity of cytology, ImmunoCyt/uCyt and combined analyses reached 29, 74 and 84%, respectively, and overall specificity was 98, 62 and 61%. The negative predictive value of cytology, ImmunoCyt/uCyt and both analyses was 88, 93 and 95%, respectively, and the positive predictive value was 70, 26 and 29%. The sensitivity of cytology for low malignant potential neoplasms, low- and high-grade papillary carcinomas was 6, 18 and 53%, while it reached 71, 79 and 93% when combined with ImmunoCyt/uCyt. The sensitivity of cytology for stages Ta, T1, T2 and over and Tis tumors was 12, 67, 47 and 50%, while it reached 78, 83, 79 and 100% when combined with ImmunoCyt/uCyt. In the absence of tumor on cystoscopy but with positive ImmunoCyt/uCyt, 18% of patients developed a tumor, 2-6 months later. Of the 109 cases diagnosed as suspicious for malignancy by cytology, a tumor was present in 30 cases and ImmunoCyt/uCyt was positive in 22 (73%) of them. In conclusion, ImmunoCyt/uCyt may be used to postpone cystoscopies in patients followed for bladder cancer and may help to save cytologist and pathologist screening time.

Identification of genes up-regulated in urothelial tumors: the 67-kd laminin receptor and tumor-associated trypsin inhibitor

Studies investigating changes in gene expression in urothelial carcinoma have generally compared tumors of different stages and grades but comparisons between low-grade, noninvasive tumors and normal urothelium are needed to identify genes involved in early tumor development. We isolated the urothelium from a low-grade tumor and corresponding normal mucosa by laser capture microdissection on frozen sections. The RNA extracted was amplified to generate suppressive subtractive cDNA libraries. Random sequencing of cDNA clones identified approximately 100 unique species. Of these 83% were known genes, 15% had homology to genes with an unknown function in humans, and 2% did not show homology to any published gene sequence. Two of the known genes, the 67-kd laminin receptor (67LR) and tumor-associated trypsin inhibitor (TATI), had previously been associated with metastatic progression in many tumor types, although 67LR has not been investigated in urothelial tumors. Immunolabeling of the original tissue with antibodies against these two genes confirmed overexpression, validating our strategy: 67LR was not expressed in the normal urothelium but was present in the tumor, whereas TATI expression was confined to umbrella cells in the normal urothelium, but extended to all cell layers in the tumor. We investigated both markers further in a separate series of tumors of different stages and grades. TATI was more consistently overexpressed than 67LR in all tumor grades and stages. Levels of secreted TATI were significantly higher in urine samples from patients with tumors compared to controls. Our strategy, combining laser capture microdissection and cDNA library construction, has identified genes that may be involved in the early phases of urothelial tumor development rather than with disease progression, highlighting the importance of comparing tumor with normal rather than just tumors of different stages and grades.

Current bladder cancer tests: unnecessary or beneficial?

Bladder cancer is currently diagnosed using cystoscopy and cytology in patients with suspicious signs and symptoms. These same tests are used to monitor patients with a history of bladder cancer for recurrence. The recurrence rate for bladder cancer is high, thus necessitating long-term follow-up. Urine cytology requires an experienced cytopathologist and is costly. It has high specificity, but low sensitivity for low-grade bladder tumors. Recently many non-invasive bladder cancer tests, utilizing markers found in the urine, have been developed. The FDA has approved several of these for the use is bladder cancer diagnosis, and many others are undergoing development and investigation. An ideal bladder cancer test would be non-invasive, highly sensitive and specific, inexpensive, easy to perform, and yield highly reproducible results. Many of the tests reviewed meet some, but not all, of these criteria.

Are false-positive urine markers for the detection of bladder carcinoma really wrong or do they predict tumor recurrence?

INTRODUCTION AND OBJECTIVES

A problem in the interpretation of noninvasive urine tests for detection of bladder carcinoma is the finding of false-positive results. Several authors have described that patients with false-positive results are at high risk for tumor recurrence or progression. Only few data are available for comparing the clinical course of patients with false-positive test results and patients with true-negative results. We studied whether patients with false-positive results of various urine test had a higher recurrence rate than patients with true-negative results.

METHODS

Urine samples from 61 patients without evidence of active bladder carcinoma were included. Of the 61 patients, 51 had a history of bladder cancer, and 10 underwent transurethral resection for suspect of bladder carcinoma but had negative pathologic findings. Immunocytology (Lewis X and 486p3/12) was performed on bladder washings, and BTAstat and NMP22 were performed on urine samples.

RESULTS

During the follow-up period, 22 patients had one or more false-positive BTAstat test results, 25 patients had one or more false-positive NMP22 tests, 42 patients had at least one false-positive Lewis X test, and 11 patients had one or more false-positive 486p3/12 test. During a follow-up period of 3-39 months (median, 17.6 months) four patients expected a tumor recurrence. Among patients with false-positive urine test results 2 of 22 (9.1%, BTAstat), 2 of 25 (8%, NMP22), 4 of 42 (9.5%, Lewis X), and 3 of 11 (27.2%, 486p3/12) suffered from tumor recurrence. In contrast, among patients with true-negative test results 2 of 39 (5.2%, BTAstat), 2 of 36 (5.6%, NMP22), 0 of 18 (0%, Lewis X), 1 of 50 (2.0%, 486p3/12) had a tumor recurrence.

CONCLUSIONS

Patients with a false-positive urine test result do not generally have a greater risk of tumor recurrence or progression than patients with a true-negative result. In our series, only patients with false-positive 486p3/12 test result had a higher recurrence rate. Our findings do not justify a more aggressive adjuvant treatment or surveillance for patients with false-positive urine tests.

Can biological markers replace cystoscopy? An update

Cystoscopy is currently considered the gold standard for the detection of bladder tumors. The role of urine cytology in the initial detection and follow-up of patients is under discussion. New elaborative and rapid assays are available that may circumvent the low sensitivity and poor reproducibility of urine cytology. The methods that have been tested extensively are the nuclear matrix protein (NMP22) assay, the BTA stat assay, and the BTA TRAK enzyme-linked immunosorbent assay. Both outperform cytology in the detection of low-grade lesions. The specificity of both assays, however, lags behind that of cytology. The data from retrospective analyses are insufficient to justify clinical integration, and the need to replace cystoscopy with these novel assays remains to be proven.