Bladder tumor antigen assay as compared to voided urine cytology in the diagnosis of bladder cancer

Upregulated GRB7 promotes proliferation and tumorigenesis of Bladder Cancer via Phospho-AKT Pathway

Growth factor receptor-bound protein 7 (GRB7) has been found closely related to the occurrence and development of various tumors, but its function in bladder cancer has not yet been elucidated. The study is aiming at investigating the expression and function of GRB7 in bladder cancer. The Cancer Genome Atlas (TCGA) database was selected to analyze mRNA levels of GRB7 in bladder cancer. RT-qPCR and Western blot were conducted to detect the expression of GRB7 in normal bladder epithelial cells, seven bladder cancer cell lines and eight pairs of malignant/nonmalignant bladder tissues. The role of GRB7 in tumor proliferation and tumorigenesis was explored by establishing stable cells, in vitro cell experiments and in vivo xenograft models. The molecular regulation mechanism of GRB7 in bladder cancer was investigated by treatment with AKT inhibitor. GRB7 mRNA was upregulated in bladder cancer samples compared with that in normal tissue samples. Overexpressing GRB7 significantly promoted the proliferation and tumorigenesis of bladder cancer. However, silencing GRB7 played the retarding part. GRB7 promoted G1/S transition by activating the AKT pathway. Our results indicate that GRB7 plays an important role in promoting proliferation and tumorigenesis of bladder cancer.

Fast Screening of Whole Blood and Tumor Tissue for Bladder Cancer Biomarkers Using Stochastic Needle Sensors

Bladder cancer is one of the most common urologic malignancies, which is more frequent in men than in women. The early diagnosis for this type of cancer still remains a challenge, therefore, the development of a fast screening test for whole blood and tumor tissue samples may save lives. Four biomarkers, p53, E-cadherin, bladder tumor antigen (BTA), and hyaluronic acid were considered for the screening tests using stochastic needle sensors. Three stochastic needle sensors, based on graphite powder and modified with three types of chitosan, were designed and characterized for the screening test. The proposed sensors showed low limits of quantification, and high sensitivity and selectivity levels. The recoveries of p53, E-cadherin, BTA, and hyaluronic acid in whole blood samples and tissue samples were higher than 95.00% with a relative standard deviation lower than 1.00%.

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.

Epigenetic markers as promising prognosticators for bladder cancer

Transitional cell carcinomas of the urinary bladder have diverse biological and functional characteristics. Surveillance strategies for bladder cancer recurrence have historically relied on the diagnostic combination of cystoscopy and urinary cytology. However, the accuracy of both tests depends on subjective and operator-dependent interpretations of the visible findings. In contrast, promoter hypermethylation of CpG islands is strongly associated with tumor development and prognosis of bladder cancer. Detection of DNA methylation in voided urine may be feasible and more sensitive than conventional urine cytology. Ultimately, all types of urological cancers may be screened in urine using a candidate panel of hypermethylated genes. The epigenetic silencing of tumor suppressor genes is interest from a clinical point of view because it is possible to reverse epigenetic changes and restore gene function to a cell. Methylation markers might therefore be more useful than conventional molecular markers for the treatment and prevention of bladder 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.

Intérêt des marqueurs urinaires dans le diagnostic et le suivi des tumeurs urothéliales de vessie

Urothelial bladder tumours require regular surveillance: cystoscopy associated with urine cytology are reference examinations. Several new markers currently under evaluation or already validated have recently been proposed to replace cytology and potentially reduce or even replace unnecessary cystoscopies. The biological fluid studied for all of these markers is the same as that of urine cytology, i.e. urine. The authors review the results of recent studies on these new urinary markers. The results of these markers demonstrate a better global sensitivity than urine cytology, but often a lower specificity. In the majority of cases, these tests are performed during patient follow-up (NMP22, BTA, CYFRA 21-l., etc.), but do not replace cystoscopy, due to a large number of false-positives. Other techniques, such as FISH, uCyt+ or microsatellites appear to be more promising, especially for the diagnosis of low-grade tumours. The best solution in practice may consist of a combination of several markers to further improve sensitivity and to decrease the false-positive rate responsible for unnecessary cystoscopies.

[Tumor marker tests in bladder cancer]

The gold standard for detecting bladder cancer is cystoscopy which identifies nearly all papillary and sessile lesions. However, it is an invasive procedure causing some discomfort for patients. Urine cytology is the standard non-invasive marker with very high specificity, but unfavourable poor sensitivity for Ta, G1, and T1 bladder tumors. To improve early detection of bladder cancer as well as to monitor treatment response and tumor recurrence, bladder tumor markers are eligible. An ideal bladder cancer test would have the potential to replace or delay cystoscopy in the follow-up of bladder cancer patients. In recent years, the FDA approved non-invasive tumor marker tests ImmunoCyt / uCyt+, BTA TRAK, BTA stat, NMP22, NMP22 BladderChek, and UroVysion have been investigated. The tests demonstrated higher sensitivity for diagnosis of bladder cancer compared to urine cytology. Overall, the mean sensitivity and mean specificity was 64-80% and 71-95% and the mean positive and negative predictive values to detect malignancy were 49-84% and 79-95%, respectively. BTA TRAK, BTA stat, NMP22, and NMP22 BladderChek assays are limited by false-positive results in patients with benign urological diseases such as hematuria, urocystitis, renal calculi or urinary tract infections. Due to low specificity BTA TRAK, BTA stat, NMP22, and NMP22 BladderChek should not be used without first ruling out benign or malignant genitourinary disease other than bladder cancer. With the exception of UroVysion achieving 80% sensitivity and 94% specificity, none of these non-invasive tests revealed a high sensitivity and specificity at the same time, which is a main demand to be made on an ideal tumor marker. Insufficient sensitivity along with limited specificity does not allow replacing cystoscopy in diagnosis of bladder cancer or treatment decisions based on a positive test result.

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.

DNA breaks as measured by the alkaline comet assay in exfoliated cells as compared to voided urine cytology in the diagnosis of bladder cancer: a study of 105 subjects

In this study we evaluated the clinical usefulness of identifying urothelial cells with increased DNA damage with the alkaline comet assay and compare it with voided urine cytology for the assessment of markers indicative of bladder cancer. The analysis was carried out on 105 subjects having clinical suspicion of bladder cancer, and who had undergone cytology for the first time. Urine cytology and alkaline comet assay were performed on the same fresh urine samples obtained from each patient. The subjects were divided according to negative or positive cytology. The Mann-Whitney U-test showed that the comet parameters (tail moment, tail length, and % of DNA in the tail) and the numbers of comets (cells with an arbitrary cut-off value of head intensity <90% of DNA content) in subjects positive in both tests were significantly higher than in the negative group. Sensitivity, specificity, and positive and negative predictive value of the comet assay were compared with those of cytology, which is regarded as the gold standard. Sensitivity was 71.4%, specificity was 91.8%, positive and negative predictive values were 38.5 and 97.8, respectively. Two subjects negative in the comet assay were positive in cytology. Eight patients were positive in the comet assay and negative for cytology. Interestingly, one of these eight patients was later found positive for cytology. Logistic regression analysis indicates that the tail moment is significantly associated with an increased risk for positive cytology.

Tumor markers in the diagnosis of primary bladder cancer. A systematic review

PURPOSE

We systematically reviewed the available evidence, and obtained and compared summary estimates of the sensitivity and specificity of cytology and the urine based markers bladder tumor antigen, BTA stat (Polymedco, Redmond, Washington), BTA TRAK (Polymedco), NMP22 (Matritech, Cambridge, Massachusetts), telomerase and fibrin degradation product in detecting primary bladder cancer.

MATERIALS AND METHODS

Studies on the diagnosis of primary bladder cancer published from 1990 through November 2001 in English and German were retrieved from MEDLINE and EMBASE data bases. In our research we included studies that evaluated 1 or more of the markers, used cystoscopy as the reference standard and allowed the construction of a 2 x 2 contingency table for a per patient analysis. The data plus items on study and clinical characteristics were extracted by 2 observers. Sensitivity and specificity for each marker were estimated using a bivariate random effect meta-analysis. A multivariable analysis was performed to explain study variation.

RESULTS

A total of 42 studies were included in our review. Only 2 studies were available on fibrin degradation product, hence a meta-analysis was not possible. Cytology had the best specificity at 94% (95% CI: 90% to 96%). This figure was significantly better than that of the other markers except for telomerase (specificity 86% [71% to 94%]). Telomerase had the best sensitivity (75% [71% to 79%]) but it was not significantly better than that of BTA stat (70% [66% to 74%]). Case control designs yielded lower values for sensitivity for the tumor markers cytology, bladder tumor antigen and BTA stat.

CONCLUSIONS

Cytology has the best specificity and telomerase the best sensitivity. However, none of the markers studied here is sensitive enough to be recommended for daily routine.