Optical sensory arrays for the detection of urinary bladder cancer‐related volatile organic compounds

Non‐invasive detection of urinary bladder cancer remains a significant challenge. Urinary volatile organic compounds (VOCs) are a promising alternative to cell‐based biomarkers. Herein, we demonstrate a novel diagnosis system based on an optic fluorescence sensor array for detecting urinary bladder cancer VOCs biomarkers. This study describes a fluorescence‐based VOCs sensor array detecting system in detail. The choice of VOCs for the initial part was based on an extensive systematic search of the literature and then followed up using urinary samples from patients with urinary bladder transitional cell carcinoma. Canonical discriminant analysis and partial least squares discriminant analysis (PLS‐DA) were employed and correctly detected 31/48 urinary bladder cancer VOC biomarkers and achieved an overall 77.75% sensitivity and 93.25% specificity by PLS‐DA modelling. All five urine samples from bladder cancer patients, and five healthy controls were successfully identified with the same sensor arrays. Overall, the experiments in this study describe a real‐time platform for non‐invasive bladder cancer diagnosis using fluorescence‐based gas‐sensor arrays. Pure VOCs and urine samples from the patients proved such a system to be promising; however, further research is required using a larger population sample.      

Enterococcus faecalis Subverts and Invades the Host Urothelium in Patients with Chronic Urinary Tract Infection

Bacterial urinary tract infections (UTI) are a major growing concern worldwide. Uropathogenic Escherichia coli has been shown to invade the urothelium during acute UTI in mice and humans, forming intracellular reservoirs that can evade antibiotics and the immune response, allowing recurrence at a later date. Other bacterial species, such as Staphylococcus saprophyticus, Klebsiella pneumonia and Salmonella enterica have also been shown to be invasive in acute UTI. However, the role of intracellular infection in chronic UTI causing more subtle lower urinary tract symptoms (LUTS), a particular problem in the elderly population, is poorly understood. Moreover, the species of bacteria involved remains largely unknown. A previous study of a large cohort of non-acute LUTS patients found that Enterococcus faecalis was frequently found in urine specimens. E. faecalis accounts for a significant proportion of chronic bladder infections worldwide, although the invasive lifestyle of this uropathogen has yet to be reported. Here, we wanted to explore this question in more detail. We harvested urothelial cells shed in response to inflammation and, using advanced imaging techniques, inspected them for signs of bacterial pathology and invasion. We found strong evidence of intracellular E. faecalis harboured within urothelial cells shed from the bladder of LUTS patients. Furthermore, using a culture model system, these patient-isolated strains of E. faecalis were able to invade a transitional carcinoma cell line. In contrast, we found no evidence of cellular invasion by E. coli in the patient cells or the culture model system. Our data show that E. faecalis is highly competent to invade in this context; therefore, these results have implications for both the diagnosis and treatment of chronic LUTS.     

Proteomic strategies in bladder cancer

Here we review our current strategy for identifying phenotypic changes in the urothelium of bladder cancer patients with invasive disease, using a combination of proteomic technologies and immunowalking. This approach, which in principle can be applied to the study of any type of bladder cancer, makes use of proteomic technologies (for more information see http://biobase.dk/cgi-bin/celis) to reveal and identify proteins that are differentially expressed in fresh tumors and normal urothelium. Thereafter, specific antibodies against the differentially expressed proteins are used (immunowalking) to stain serial cryostat sections of cystectomies obtained from tumor-bearing patients who have undergone removal of the bladder for invasive disease. Since bladder cancer is a field disease--that is, a large part of the bladder lining is involved-the urothelium of these patients is expected to exhibit a spectrum of abnormalities, ranging from early stages of transformation to invasive disease. Besides highlighting the problems one faces when applying powerful proteomic technologies to the study of heterogeneous biopsy material, these studies show that it is feasible to study bladder cancer under experimental conditions that closely resemble the in vivo situation.     

Proteomic analysis of urinary biomarker candidates for nonmuscle invasive bladder cancer

Nonmuscle invasive tumors of the bladder often recur and thereby bladder cancer patients need regular re-examinations which are invasive, unpleasant, and expensive. A noninvasive and less expensive method, e.g. a urine dipstick test, for monitoring recurrence would thus be advantageous. In this study, the complementary techniques mass spectrometry (MS) and Western blotting (WB)/dot blot (DB) were used to screen the urine samples from bladder cancer patients. High resolving MS was used to analyze and quantify the urinary proteome and 29 proteins had a significantly higher abundance (p<0.05) in bladder cancer samples compared with control urine samples. The increased abundance found in urine from bladder cancer patients compared with controls was confirmed with Western blot for four selected proteins; fibrinogen β chain precursor, apolipoprotein E, α-1-antitrypsin, and leucine-rich α-2-glycoprotein 1. Dot blot analysis of an independent urine sample set pointed out fibrinogen β chain and α-1-antitrypsin as most interesting biomarkers having sensitivity and specificity values in the range of 66-85%. Exploring the Human Protein Atlas (HPA) also revealed that bladder cancer tumors are the likely source of these proteins. They have the potential of being useful in diagnosis, monitoring of recurrence and thus may improve the treatment of bladder tumors, especially nonmuscle invasive tumors.     

Multiplexed quantification of 63 proteins in human urine by multiple reaction monitoring-based mass spectrometry for discovery of potential bladder cancer biomarkers

Three common urological diseases are bladder cancer, urinary tract infection, and hematuria. Seventeen bladder cancer biomarkers were previously discovered using iTRAQ - these findings were verified by MRM-MS in this current study. Urine samples from 156 patients with hernia (n=57, control), bladder cancer (n=76), or urinary tract infection/hematuria (n=23) were collected and subjected to multiplexed LC-MRM/MS to determine the concentrations of 63 proteins that are normally considered to be plasma proteins, but which include proteins found in our earlier iTRAQ study. Sixty-five stable isotope-labeled standard proteotypic peptides were used as internal standards for 63 targeted proteins. Twelve proteins showed higher concentrations in the bladder cancer group than in the hernia and the urinary tract infection/hematuria groups, and thus represent potential urinary biomarkers for detection of bladder cancer. Prothrombin had the highest AUC (0.796), with 71.1% sensitivity and 75.0% specificity for differentiating bladder cancer (n=76) from non-cancerous (n=80) patients. The multiplexed MRM-MS data was used to generate a six-peptide marker panel. This six-peptide panel (afamin, adiponectin, complement C4 gamma chain, apolipoprotein A-II precursor, ceruloplasmin, and prothrombin) can discriminate bladder cancer subjects from non-cancerous subjects with an AUC of 0.814, with a 76.3% positive predictive value, and a 77.5% negative predictive value. This article is part of a Special Section entitled: Understanding genome regulation and genetic diversity by mass spectrometry.     

尿液蛋白质组在膀胱癌临床诊治中的应用

膀胱癌是一种常见的泌尿系统疾病,尿细胞学检查与膀胱镜检查是膀胱癌的主要临床诊断手段,但尿细胞学检查敏感性较差,膀胱镜检查为侵入性检查,易给病人带来强烈的不适感;且膀胱癌具有易复发的特点,大部分患者必须面临频繁的检查,临床亟需发展舒适、准确的检查手段.尿液存储是膀胱的主要生理作用,尿液可以直接接触肿瘤实体,肿瘤分泌的一些蛋白质分子极可能进入尿液中,并且患者尿液样本便于足量多次收集.同时,蛋白质组技术以及尿液蛋白质组研究的快速发展,为我们利用尿液研究膀胱癌提供了便利的途径.本文系统总结了尿液蛋白质组研究的主要技术手段,重点关注膀胱癌尿液蛋白质组研究趋势和应用方向,以期为利用尿液蛋白质组研究膀胱癌提供助力.     

尿液诊断膀胱癌的研究进展

摘要：膀胱癌是临床常见的发生在泌尿系统的恶性肿瘤,该病的发病率呈现逐年升高的趋势,其复发率也相对较高。早期诊断和定期随访是保证膀胱癌患者长期生存的关键。对于膀胱癌的诊断以及患者的随访通常凭借膀胱镜检查或尿脱落细胞学的测定。然而,前者的检查费用较为昂贵,且属于有创诊断;后者则具有检查敏感性相对较低的特点,还存在较大程度受病理科诊断医生主观因素影响的局限,目前还没有尿液生物标志物可以替代传统的诊断方法。膀胱肿瘤具有广泛的异质性,不同的疾病表型具有不同的分子差异。因此,引入尿液生物标志物来诊断疾病,评估疾病的侵袭性、进展的风险、复发的可能性和预后具有重要的临床价值。本文总结了目前尿液所含生物标志物诊断膀胱癌的研究现状,并对此领域的主要研究进展进行综述。     

Insights into a multidrug resistant Escherichia coli pathogen of the globally disseminated ST131 lineage: genome analysis and virulence mechanisms

Escherichia coli strains causing urinary tract infection (UTI) are increasingly recognized as belonging to specific clones. E. coli clone O25b:H4-ST131 has recently emerged globally as a leading multi-drug resistant pathogen causing urinary tract and bloodstream infections in hospitals and the community. While most molecular studies to date examine the mechanisms conferring multi-drug resistance in E. coli ST131, relatively little is known about their virulence potential. Here we examined E. coli ST131 clinical isolates from two geographically diverse collections, one representing the major pathogenic lineages causing UTI across the United Kingdom and a second representing UTI isolates from patients presenting at two large hospitals in Australia. We determined a draft genome sequence for one representative isolate, E. coli EC958, which produced CTX-M-15 extended-spectrum β-lactamase, CMY-23 type AmpC cephalosporinase and was resistant to ciprofloxacin. Comparative genome analysis indicated that EC958 encodes virulence genes commonly associated with uropathogenic E. coli (UPEC). The genome sequence of EC958 revealed a transposon insertion in the fimB gene encoding the activator of type 1 fimbriae, an important UPEC bladder colonization factor. We identified the same fimB transposon insertion in 59% of the ST131 UK isolates, as well as 71% of ST131 isolates from Australia, suggesting this mutation is common among E. coli ST131 strains. Insertional inactivation of fimB resulted in a phenotype resembling a slower off-to-on switching for type 1 fimbriae. Type 1 fimbriae expression could still be induced in fimB-null isolates; this correlated strongly with adherence to and invasion of human bladder cells and bladder colonisation in a mouse UTI model. We conclude that E. coli ST131 is a geographically widespread, antibiotic resistant clone that has the capacity to produce numerous virulence factors associated with UTI.     

The systematic histologic elaboration of urinary bladders with different pathologic findings (urinary bladder carcinoma, tumor-free aging urinary bladders)

We report our systematic histological examinations of 16 urinary bladders (11 bladders with cancer, 5 bladders was tumour-free). All residual tumour-free portions in bladder with multiple or solitary cancers demonstrated various precancerous variations of urothelium, not only near the tumours. In 1 urinary bladder among 5 from elder patients, we diagnosed a clinically undetected cancer. In a few cases, we correlated histological examinations with graphical demonstration (through a computer) of the exophytic tumour portions. Our results agree with individual therapy of urinary bladder cancer.     

Discovery of Apo-A1 as a potential bladder cancer biomarker by urine proteomics and analysis

Bladder cancer is clinically characterized by high recurrent rate and poor prognosis and thereby patients need regular re-examinations which are invasive, unpleasant, and expensive. A noninvasive and less expensive method for detecting and monitoring bladder cancer would thus be advantageous. In this study, by using the two-dimensional electrophoresis (2-DE) approach with subsequent mass spectrometry (MS), we demonstrated the increased expression of apolipoprotein-A1 (Apo-A1) in individual urine from patients with bladder cancer, which was confirmed by Western blot results. A further analysis of the urinary Apo-A1 levels by an enzyme-linked immunosorbent assay yielded results that were consistent with the Western blot, and suggested Apo-A1 could provide diagnostic utility to distinguish patients with bladder cancer from healthy controls at 19.21 ng/ml. Further validation assay in a larger number of urine samples (n = 379) showed that Apo-A1 could be used as a biomarker to diagnosis bladder cancer with a sensitivity and specificity of 89.2% and 84.6% respectively. Moreover, the application of exfoliative urinary cytology in combination with the urine Apo-A1 detection could significantly increased the sensitivity in detecting bladder cancer. Our data showed a significant relationship of expressed Apo-A1 was established between bladder cancer and normal controls. Apo-A1 could be a potential biomarker for the diagnosis of bladder cancer.     

非肌层侵润性膀胱癌的治疗

膀胱癌是一种全球性疾病。在我国泌尿外科肿瘤中的发病率和死亡率均占首位,非肌层侵润性膀胱癌占初发膀胱肿瘤的70%。对膀胱癌的研究已成为目前学术界的热点话题。目前学界对于非肌层侵润性膀胱癌主要采用以外科手术为主的综合治疗方案。为探讨该类肿瘤的治疗方法,本文就近年来对非肌层侵润性膀胱癌的各种治疗措施进行了比较系统的阐述。我们希望能尽可能的找到高效低风险并且经济的方法,为膀胱癌的诊断和治疗提供新途径。     

NMR-based metabolomics study of canine bladder cancer

Bladder cancer is one of the leading lethal cancers worldwide. With the high risk of recurrence for bladder cancer following the initial diagnoses, lifelong monitoring of patients is necessary. The lack of adequate sensitivity and specificity of current noninvasive monitoring approaches including urine cytology, other urine tests, and imaging, underlines the importance of studies that focus on the detection of more reliable biomarkers for this cancer. The emerging area of metabolomics, which deals with the analysis of a large number of small molecules in a single step, promises immense potential for discovering metabolite markers for screening and monitoring treatment response and recurrence in patients with bladder cancer. Since naturally-occurring canine transitional cell carcinoma of the urinary bladder is very similar to human invasive bladder cancer, spontaneous canine transitional cell carcinoma has been applied as a relevant animal model of human invasive transitional cell carcinoma. In this study, we have focused on profiling the metabolites in urine from dogs with transitional cell carcinoma and healthy control dogs combining nuclear magnetic resonance spectroscopy and statistical analysis methods. ¹H NMR-based metabolite profiling analysis was shown to be an effective approach for differentiating samples from dogs with transitional cell carcinoma and healthy controls based on a partial least square-discriminant analysis of the NMR spectra. In addition, there were significant differences in the levels of six individual metabolites between samples from dogs with transitional cell carcinoma and the control group based on the Student's t-test. These metabolites were selected to build a separate partial least square‐discriminant analysis model that was then used to test the classification accuracy. The result showed good classification between transitional cell carcinoma and control groups with the area under the receiver operating characteristic curve of 0.85. The sensitivity and specificity of the model were 86% and 78%, respectively. These results suggest that urine metabolic profiling may have potential for early detection of bladder cancer and of bladder cancer recurrence following treatment, and may enhance our understanding of the mechanisms involved.     

Metatarsal metastasis from transitional cell cancer of the urinary bladder

Urinary bladder cancers can be grouped into three general categories: superficial, invasive and metastatic. Approximately 90% of malignant tumors of the urinary bladder are of epithelial origin and the majority of them are transitional cell carcinomas (TCC). Metastatic spread of urinary bladder cancers usually includes regional lymph nodes, the lung, the liver and the bones. The presence of metastasis tends to correlate with muscular wall invasion as often demonstrated at the initial diagnosis; consequently clinical bladder cancer represents a late phase of the disease. Although skeletal metastases of bladder cancers are rather common, they have been rarely described to occur in distal bones. For that reason, we report metatarsal metastasis from transitional cell cancer of the urinary bladder in a 59-year-old woman.     

Tumor markers (CEA, TPA and CA 19-9) in urine of bladder cancer patients

This study was carried out to evaluate the usefulness of determining urinary levels of carcinoembryogenic antigen (CEA), tissue-polypeptide antigen (TPA), and gastro-intestinal cancer antigen (Ca19-9) in addition to the usual diagnostic procedures for bladder cancer. Sixty-seven patients with transitional bladder cancer, 40 healthy controls and 20 patients with inflammatory diseases of the urinary tract were considered. All urine samples were obtained from patients with intact renal function and no urinary tract infection. TPA and Ca19-9 urinary levels in patients with G3 bladder tumors were significantly higher than in those with lower graded neoplasms. The sensitivity, specificity, and predictive value of a positive (PV+) or negative (PV-) test and the diagnostic accuracy were also evaluated. Ca19-9 was the best urinary marker for bladder cancer (sensitivity 71.6%, specificity 91.6%, PV+ 90.5%, PV- 74.3%, diagnostic accuracy 81%).     

Percutaneous nephrostomy--a retrospective study focused on palliative indications

We present an overview of the fast development of less invasive techniques in intrarenal surgery all based on percutaneous nephrostomy. Life-long urinary diversion with nephrostomy is often necessary in patients with malignant disease and such patients have more postnephrostomy complications than patients with kidney stones and their survival is short. In a follow-up of 246 patients with 275 nephrostomies performed consecutively over two years, mean survival after urinary diversion was only 7.9 months in 38 prostate cancer patients with ureteral obstruction and only 5.3 months in 20 patients with advanced bladder cancer. We emphasize the necessity of informing the patient and his/her family of the expected outcome of the procedure and the importance of using carefully chosen and realistic indications.     

The use of hierarchic classification in the image analysis of a complex cell population. Experience with the sediment of voided urine

Microscopic analysis of cells in the sediment of voided urine is the principal noninvasive method of diagnosing and detecting cancer of the lower urinary tract, mainly the bladder. The sediments contain several populations of cells of unequal diagnostic value. By applying a system of hierarchic classification to the computer analysis of digitized cell images, we were able to eliminate from diagnostic consideration cells that are difficult to classify, such as degenerated cells, multinucleated cells, cell clusters, renal tubular cells and cells infected by the human polyomavirus. When this method of triage was applied to the images of sequentially encountered epithelial cells and clusters, the cell images accepted for final analysis by the computer were sufficient in number and quality to automatically construct cytologic profiles of documented diagnostic value in 15 patients with bladder cancer. The method proved to be applicable to smears and quantitative cytocentrifuge preparations processed by methods developed in our laboratory. This work clearly documents the feasibility of automated analysis of cells in voided urine for the purpose of diagnosing bladder cancer. It also confirms prior observations suggesting that a relatively small sample of sequential images of epithelial cells (200 to 300) is sufficient to establish a diagnostic profile of clinical value on patients with high-grade cancer of the urinary bladder.     

Macrophage inflammatory protein-2, neutrophil recruitment and bacterial persistence in an experimental mouse model of urinary tract infection

This study analyzed macrophage inflammatory protein-2 (MIP-2) production and neutrophil recruitment in urinary tract in response to Pseudomonas aeruginosa in an ascending model of urinary tract infection (UTI) in mice. Both planktonic and biofilm cells of P. aeruginosa were used for inducing UTI in mice. MIP-2 levels determined in urine, bladder and kidney showed maximum MIP-2 production 6 h postinfection, which correlated with neutrophil recruitment. Biofilm cells showed significantly more MIP-2 production and neutrophil recruitment. However, no correlation between bacterial numbers and neutrophil recruitment was observed in urine and kidney tissue. The role of MIP-2 and neutrophils in relation to the persistence of P. aeruginosa in the urinary tract of mice is discussed.