Insight into the Interplay of Gd-IgA1, HMGB1, RAGE and PCDH1 in IgA Vasculitis (IgAV).

The pathogenesis of IgAV, the most common systemic vasculitis in childhood, appears to be complex and requires further elucidation. We aimed to investigate the potential role of galactose-deficient immunoglobulin A1 (Gd-IgA1), high-mobility group box 1 (HMGB1), receptor for advanced glycation end products (RAGE) and protocadherin 1 (PCDH1) in the pathogenesis of IgAV. Our prospective study enrolled 86 patients with IgAV and 70 controls. HMGB1, RAGE, Gd-IgA1 and PCDH1 in serum and urine were determined by the enzyme-linked immunosorbent assay (ELISA) method at the onset of the disease and after a six-month interval in patients and once in the control group. Serum concentrations of HMGB1, RAGE and PCDH1 and urinary concentrations of HMGB1, RAGE, Gd-IgA1 and PCDH1 were significantly higher in patients with IgAV than in the control group (p < 0.001). Concentrations of HMGB1 (5573 pg/mL vs. 3477 pg/mL vs. 1088 pg/mL, p < 0.001) and RAGE (309 pg/mL vs. 302.4 pg/mL vs. 201.3 pg/mL, p = 0.012) in the serum of patients remained significantly elevated when the disease onset was compared with the six-month follow-up interval, and thus could be a potential marker of disease activity. Urinary concentration of HMGB1 measured in the follow-up period was higher in patients with nephritis compared to IgAV without nephritis (270.9 (146.7-542.7) ng/mmol vs. 133.2 (85.9-318.6) ng/mmol, p = 0.049) and significantly positively correlated with the urine albumine to creatinine ratio (τ = 0.184, p < 0.05), the number of erythrocytes in urine samples (τ = 0.193, p < 0.05) and with the outcome of nephritis (τ = 0.287, p < 0.05); therefore, HMGB1 could be a potential tool for monitoring patients with IgAV who develop nephritis. Taken together, our results imply a possible interplay of Gd-IgA1, HMGB1, RAGE and PCDH1 in the development of IgAV. The identification of sensitive biomarkers in IgAV may provide disease prevention and future therapeutics.

Improved urine DNA methylation panel for early bladder cancer detection.

BACKGROUND: Bladder cancer is one of the most common malignancies but the corresponding diagnostic methods are either invasive or limited in specificity and/or sensitivity. This study aimed to develop a urine-based methylation panel for bladder cancer detection by improving published panels and validate performance of the new panel with clinical samples. METHODS: Related researches were reviewed and 19 potential panels were selected. RRBS was performed on a cohort with 45 samples to reassess these panels and a new panel inherited best markers was developed. The new panel was applied with qMSP platform to 33 samples from the RRBS cohort and the results were compared to those of RRBS. Lastly, another larger cohort with 207 samples was used to validate new panel performance with qMSP. RESULTS: Three biomarkers (PCDH17, POU4F2 and PENK) were selected to construct a new panel P3. P3 panel achieved 100% specificity and 71% sensitivity with RRBS in corresponding cohort and then showed a better performance of 100% specificity and 84% sensitivity with qMSP platforms in a balanced cohort. When validated with 207-sample cohort, P3 with qMSP showed a performance of 97% specificity and 87% sensitivity which was modestly improved compared to the panels it derided from. CONCLUSIONS: Overall, the P3 panel achieved relatively high sensitivity and accuracy in bladder cancer detection.

HOXA9, PCDH17, POU4F2, and ONECUT2 as a Urinary Biomarker Combination for the Detection of Bladder Cancer in Chinese Patients with Hematuria.

BACKGROUND: DNA methylation biomarkers for bladder cancer (BCa) have not been evaluated extensively in the Chinese population. OBJECTIVE: To develop and validate a urinary biomarker combination of methylation assays in a group of Chinese patients with hematuria. DESIGN, SETTING, AND PARTICIPANTS: A total of 192 urine samples were collected and evaluated from patients with microscopic or gross hematuria, including 97 BCa patients and 95 controls with benign diseases. A two-stage study was conducted: the first stage being assay construction and the second stage being assay validation. Eighty-one urine samples were analyzed for the hypermethylation of eight selected genes in stage 1 and then a four-gene panel was constructed. An additional 111 urine samples were analyzed using the four-gene panel (including HOXA9, PCDH17, POU4F2, and ONECUT2) for independent validation. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The positive predictive value (PPV) and negative predictive value (NPV) were calculated for the combination methylation assay. Uni- and multivariate binary logistic regression analyses (backward elimination, conditional) were performed to calculate the association between BCa and each predictor variable. RESULTS AND LIMITATIONS: The combination assay of HOXA9, PCDH17, POU4F2, and ONECUT2 was selected based on the results of multivariate logistic regression analysis in stage 1. Using a strategy of three-level risk stratification, the assay yielded a consistent PPV of 100%. With an estimated BCa prevalence of 10% in a general hematuria population, the assay would result in an overall NPV of 98%. This combined methylation biomarker would yield an overall area under the receiver operating characteristic curve of 0.871 (with a sensitivity of 90.5% and a specificity of 73.2%) if using the prediction model from multivariate regression analysis. In addition, over half of BCa cases would be predicted accurately and ∼60% of unnecessary cystoscopies could be spared. This study had several limitations. First, the sample size was relatively small. Second, it was performed in a case-control population rather than in a natural hematuria cohort. CONCLUSIONS: A combination methylation assay of HOXA9, PCDH17, POU4F2, and ONECUT2 resulted in high PPV and NPV in Chinese patients with hematuria. With accurate risk prediction, the urinary biomarker combination could spare a sizeable proportion of low-risk patients from extensive and invasive examination. PATIENT SUMMARY: In the present study, we looked at the predictive performance of a urinary biomarker combination of HOXA9, PCDH17, POU4F2, and ONECUT2. We found that this urinary biomarker combination may help discriminate bladder cancer from other benign diseases in patients with hematuria, resulting in a reduction of unnecessary invasive examination in patients at low risk.

Liquid biopsy biomarkers of renal interstitial fibrosis based on urinary exosome.

Renal interstitial fibrosis (RIF) is difficult to diagnose. This paper explored liquid biopsy markers in urinary exosomes derived from RIF patients. Urine samples from 32 patients with various degrees of RIF and 20 non-RIF patients were collected. The size and morphology of urinary exosomes isolated by polyethylene glycol were observed with electron microscopy. Protein biomakers of exosomes were analyzed by Western blot. qRT-PCR was used to detect the levels of biomarkers (miR-29c, miR-21, E-cadherin, and vimentin) of epithelial mesenchymal transition in urinary exosomes. The diagnostic value was detected with ROC curves. Results displayed successfully isolated urinary exosomes. The examined miRNAs and mRNAs were checked from all urinary exosomes samples, except for two cases of RIF which lacked E-cadherin mRNA. RNA levels were different in patients with diverse degrees of RIF. Urinary miR-29c was decreased with the progress of fibrosis. Levels of E-cadherin mRNA were first decreased and then increased. The contents of miR-21 and vimentin mRNA were also depended on the degrees of RIF. ROC curve analysis showed that the area under the curve (AUC) of miR-29c was 0.8621, statistically significant compared with the non-RIF group (P < 0.05). The miR-29c level within the urinary exosomes is a promising marker for the diagnosis of RIF.

sEcad and EGF Levels Increased in Urine of Non-ferrous Metal Workers and Medium of Uroepithelial Cell Line Treated by Arsenic.

Inorganic arsenic (iAs) is a carcinogen and could increase the risks of bladder, lung, and skin cancer. Mining and smelting of non-ferrous metals are common occupational arsenic exposures. In this study, 125 individuals working in non-ferrous metal smelting plants were separated into two groups according to urinary total arsenic (TAs) levels: group 1, TAs < 100 µg/g Cr; group 2, TAs ≥ 100 µg/g Cr. Demographic characteristics of participants were obtained by questionnaire interview. Levels of E-cadherin soluble ectodomain fragment (sEcad) and epidermal growth factor (EGF) in workers urine were determined by ELISA test. We found that concentrations of sEcad and EGF present in urine were significantly elevated in the high urinary arsenic group 2 compared with the low urinary arsenic group 1. Urinary levels of the shedding of E-cadherin soluble ectodomain fragment (sEcad) and epidermal growth factor (EGF) were positively related to the concentrations of iAs in urine after adjusting for the confounding effects. A positive correlation between sEcad and EGF concentrations in urine was also observed. In order to verify the effects of iAs on sEcad and EGF, the human uroepithelial cell line (SV-HUC-1) was treated with NaAsO2 for 24 h in vitro. sEcad and EGF levels in the 4 µM NaAsO2-treated SV-HUC-1 cell medium significantly increased compared to the control group. In conclusion, urinary levels of sEcad and EGF increased in higher urinary arsenic workers of non-ferrous metal plants and are closely associated with urinary iAs concentration. The results suggested that sEcad and EGF may potentially be preclinical prognostic factors of bladder injury and early detection in arsenic exposure individuals.

Transcriptomic profiling of urine extracellular vesicles reveals alterations of CDH3 in prostate cancer.

Extracellular vesicles (EV) are emerging structures with promising properties for intercellular communication. In addition, the characterization of EV in biofluids is an attractive source of non-invasive diagnostic, prognostic and predictive biomarkers. Here we show that urinary EV (uEV) from prostate cancer (PCa) patients exhibit genuine and differential physical and biological properties compared to benign prostate hyperplasia (BPH). Importantly, transcriptomics characterization of uEVs led us to define the decreased abundance of Cadherin 3, type 1 (CDH3) transcript in uEV from PCa patients. Tissue and cell line analysis strongly suggested that the status of CDH3 in uEVs is a distal reflection of changes in the expression of this cadherin in the prostate tumor. CDH3 was negatively regulated at the genomic, transcriptional, and epigenetic level in PCa. Our results reveal that uEVs could represent a non-invasive tool to inform about the molecular alterations in PCa.

Urine survivin, E-cadherin and matrix metalloproteinases as novel biomarkers in children with chronic kidney disease.

CONTEXT: Epithelial-mesenchymal transition (EMT) leads to renal fibrosis and chronic kidney disease (CKD). OBJECTIVE: The aim of this study was to assess the usefulness of survivin, E-cadherin and metalloproteinases (MMPs) as biomarkers of CKD-related complications. MATERIAL AND METHODS: Survivin, E-cadherin, MMP-2, MMP-9 and TGFbeta1 were assessed by ELISA in 41 children with CKD stages 3 to 5 and in 23 controls. RESULTS: The serum and urine values of analyzed parameters were significantly elevated in CKD patients versus controls and correlated with each other. CONCLUSIONS: The observed parameter changes indicate apoptosis, tissue remodeling and fibrosis in CKD children. Urine survivin may become a new biomarker of kidney-specific EMT.

Stage-specific quantitative changes in renal and urinary proteome during the progression and development of streptozotocin-induced diabetic nephropathy in rats.

Diabetic nephropathy (DN) is a microvascular complication associated with diabetes causing slow deterioration of kidneys leading to end-stage renal disease. Timely intervention and diagnosis are crucial in order to ameliorate and halt the progression of DN. Current diagnosis of DN consists of urine assays for detection of microalbuminuria, which have inadequate specificity and sensitivity. Hence, there arises a need to discover stage-specific biomarkers which can aid in the early detection of DN and also in identifying the mechanisms underlying pathogenesis of DN. Therefore the present study was undertaken to identify the differentially expressed proteins in the urine and to examine the pattern of proteomic changes occurring in the rat kidneys during the course of progression of streptozotocin-induced model of DN in rats. Two-dimensional gel electrophoresis coupled to MALDI-TOF mass spectrometry was employed to identify the differentially expressed proteins under diabetic conditions. Among the identified proteins Calgranulin A and Calgranulin B appeared in the urinary proteome at the fourth week of induction of diabetes while we recorded a time-dependent decrease in the expression of major urinary protein (alpha 2u globulin) in the urine as well as kidneys of diabetic rats. Parallel monitoring of targeted proteomic changes in the renal proteome revealed an increase in histone H2B phosphorylation at serine14 along with a gradual decrease in Bcl-2 and MMP-13 expression during the course of progression and development of streptozotocin-induced DN.

Urinary biomarkers in obstructive nephropathy.

BACKGROUND AND OBJECTIVES: Obstructive nephropathy is a leading cause of CKD in children. The assessment of severity of renal impairment and the prediction of which children will progress to renal failure are, however, challenging. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This case-control study measured the urinary excretion of candidate biomarkers in 27 prevalent case-patients with posterior urethral valves (PUVs) and 20 age-matched controls, correlated their urinary concentration with GFR, and analyzed receiver-operating characteristic (ROC) curve and regression analyses to assess their performance as tests for low GFR. RESULTS: The median urinary protein-to-creatinine ratio was higher in children with PUV (45 g/mol; range, 5-361 g/mol) than in controls (7 g/mol; range, 3-43 g/mol) (P<0.01) and correlated inversely with renal function (r = -0.44; P<0.05). In whole urine, excretion of aquaporin-2 was significantly decreased, whereas that of TGFß and L1 cell adhesion molecule (L1CAM) was significantly increased. Whole-urine TGFß excretion correlated inversely with GFR (r = -0.53; P<0.05). As tests for low GFR, whole-urine TGFß, L1CAM, and urinary protein-to-creatinine ratio performed best, with areas under the ROC curves of 0.788, 0.795, and 0.814, respectively. By linear regression analysis, whole-urine TGFß, L1CAM, and urinary protein-to-creatinine ratio were associated with low GFR in the case-patients. CONCLUSIONS: Candidate biomarkers of obstructive nephropathy can be readily measured in whole urine and in urine exosomes. In boys with PUV, these biomarkers correlate with GFR.

Plasma and urine proteomic profiles in childhood idiopathic nephrotic syndrome.

PURPOSE: Idiopathic nephrotic syndrome (NS) is characterized by proteinuria, edema, and hypoalbuminemia. The aim of the study was to identify differentially expressed proteins in urine and plasma during NS compared with remission. EXPERIMENTAL DESIGN: Plasma and urine samples were collected during NS and at remission. Proteomic profiling was performed by iTRAQ labeling followed by nano-LC-MS/MS to yield data on relative protein amounts. Protein validation was performed by ELISA. RESULTS: A total of 388 and 425 proteins were detected in plasma and urine, respectively. In total, 18 plasma and 38 urinary proteins were significantly altered (p <0.05). E-cadherin was one of the proteins with reduced urinary concentration during NS, a finding validated by ELISA. The slit diaphragm protein P-cadherin was identified by nano-LC-MS/MS and shown to be reduced in urine during NS by ELISA. CONCLUSIONS AND CLINICAL RELEVANCE: The present study identified more than 50 differentially altered proteins comparing NS with remission. Several proteins were found to be linked to the major clinical symptoms of NS, and further studies must elucidate if P-cadherin is involved in proteinuria during NS, and if low urinary E-cadherin level is linked to altered epithelial cell to cell contact in the distal part of the nephron.

Discovery and validation of a molecular signature for the noninvasive diagnosis of human renal allograft fibrosis.

BACKGROUND: Tubulointerstitial fibrosis (fibrosis), a histologic feature associated with a failing kidney allograft, is diagnosed using the invasive allograft biopsy. A noninvasive diagnostic test for fibrosis may help improve allograft outcome. METHODS: We obtained 114 urine specimens from 114 renal allograft recipients: 48 from 48 recipients with fibrosis in their biopsy results and 66 from 66 recipients with normal biopsy results. Levels of messenger RNAs (mRNAs) in urinary cells were measured using kinetic, quantitative polymerase chain reaction assays, and the levels were related to allograft diagnosis. A discovery set of 76 recipients (32 with allograft fibrosis and 44 with normal biopsy results) was used to develop a diagnostic signature, and an independent validation set of 38 recipients (16 with allograft fibrosis and 22 with normal biopsy results) was used to validate the signature. RESULTS: In the discovery set, urinary cell levels of the following mRNAs were significantly associated with the presence of allograft fibrosis: vimentin (P<0.0001, logistic regression model), hepatocyte growth factor (P<0.0001), α-smooth muscle actin (P<0.0001), fibronectin 1 (P<0.0001), perforin (P=0.0002), plasminogen activator inhibitor 1 (P=0.0002), transforming growth factor ß1 (P=0.0004), tissue inhibitor of metalloproteinase 1 (P=0.0009), granzyme B (P=0.0009), fibroblast-specific protein 1 (P=0.006), CD103 (P=0.02), and collagen 1A1 (P=0.04). A four-gene model composed of the levels of mRNA for vimentin, NKCC2, and E-cadherin and of 18S ribosomal RNA provided the most accurate, parsimonious diagnostic model of allograft fibrosis with a sensitivity of 93.8% and a specificity of 84.1% (P<0.0001). In the independent validation set, this same model predicted the presence of allograft fibrosis with a sensitivity of 77.3% and a specificity of 87.5% (P<0.0001). CONCLUSIONS: Measurement of mRNAs in urinary cells may offer a noninvasive means of diagnosing fibrosis in human renal allografts.

Proteomic identification of human urinary biomarkers in diabetes mellitus type 2.

BACKGROUND: During the proteomic era, one of the most rapidly growing areas in biomedical research is biomarker discovery, particularly using proteomic technologies. The urinary proteome is known to be a valuable field of study and has become one of the most attractive subdisciplines in clinical proteomics for human diseases. We have described the levels of protein biomarkers specific to diabetes mellitus type 2 in the Pakistani population using proteomic technology. METHODS: One hundred type 2 diabetes patients with 50 age- and sex-matched normal healthy controls were recruited from Sheikh Zayed Hospital, Lahore, Pakistan. Urinary proteins were analyzed by two-dimensional liquid chromatography, using chromatofocusing in the first dimension and reverse-phase chromatography in the second, followed by mass spectrometric analysis. Levels of the proteins, which were found to vary in the diabetes type 2 patients compared to the controls, were then determined by enzyme-linked immunosorbent assay in all the samples. RESULTS: Levels of transthyretin, α-1-microglobulin/bikunin precursor, and haptoglobin precursor decreased by 30.8%, 55.2%, and 81.45%, whereas levels of albumin, zinc α2 glycoprotein, retinol binding protein 4, and E-cadherin increased by 486.5%, 29.23%, 100%, and 693%, respectively, in the diabetes patients compared to the controls. CONCLUSIONS: Variation in the levels of these identified protein biomarkers have been reported in other pathological states. Assessment of the levels of these biomarkers will be helpful not only in early diagnosis but also in prognosis of diabetes mellitus type 2.

Increase sensitivity in detecting superficial, low grade bladder cancer by combination analysis of hypermethylation of E-cadherin, p16, p14, RASSF1A genes in urine.

OBJECTIVES: To identify a better set of DNA methylation markers to detect superficial, low grade cancer cell in urine sediment for improving cancer treatment, morbidity, and mortality. MATERIALS AND METHODS: Methylation-specific PCR (MSP) assay was used to detect promoter hypermethylation in 4 genes (E-cadherin, p16, p14, and RASSF1A) to identify reliable biomarkers for bladder cancer diagnosis in primary tumor DNA and urine sediment DNA from 57 bladder cancer patients. Urine DNA was compared with 20 healthy controls. RESULTS: Fifty-one (90%) tumor DNA and 47 urine DNA (83%) samples from bladder cancer patients revealed hypermethylation in at least 1 of the 4 analyzed genes, whereas all urine samples from normal controls were negative. The sensitivity of MSP assay for detecting E-cadherin, p16, p14 and RASSF1A in tumor cells in voided urine was 35%, 35%, 33%, and 65%, respectively. Diagnostic sensitivity was 75% for combining RASSF1A and p14, and 83% for RASSF1A, p14 and E-cadherin. Urine cytology, however, detect only 13 (28%) cases of cancer or suspicious cancer. For detecting superficial and invasive bladder tumor, urine cytology revealed a sensitivity of 23% (6/26) and 35% (7/20), respectively. In contrast, MSP detected hypermethylation in the urine of 80% (37/46) bladder cancer patients. Moreover, hypermethylation analysis of E-cadherin, p14 or RASSF1A genes in urine sediment DNA detected in 85% (22/26) of superficial, 85% (11/13) of low grade, 75% (15/20) of invasive and 79% (26/33) of high grade bladder cancers. Importantly, hypermethylation was detected in the urine DNA of 90% (18/20) superficial tumors with negative or atypia cytology. CONCLUSIONS: Hypermethylation of E-cadherin, p14 or RASSF1A in urine sediment DNA is a potential biomarker for detecting superficial, low grade cancer. Besides, hypermethylation of these 3 genes is a valuable adjunct diagnostic marker to urine cytology, which can enhance the diagnostic accuracy and follow-up treatment of bladder cancer patients.

Urinary peptidome may predict renal function decline in type 1 diabetes and microalbuminuria.

One third of patients with type 1 diabetes and microalbuminuria experience an early, progressive decline in renal function that leads to advanced stages of chronic kidney disease and ESRD. We hypothesized that the urinary proteome may distinguish between stable renal function and early renal function decline among patients with type 1 diabetes and microalbuminuria. We followed patients with normal renal function and microalbuminuria for 10 to 12 yr and classified them into case patients (n = 21) with progressive early renal function decline and control subjects (n = 40) with stable renal function. Using liquid chromatography matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, we identified three peptides that decreased in the urine of patients with early renal function decline [fragments of alpha1(IV) and alpha1(V) collagens and tenascin-X] and three peptides that increased (fragments of inositol pentakisphosphate 2-kinase, zona occludens 3, and FAT tumor suppressor 2). In renal biopsies from patients with early nephropathy from type 1 diabetes, we observed increased expression of inositol pentakisphosphate 2-kinase, which was present in granule-like cytoplasmic structures, and zona occludens 3. These results indicate that urinary peptide fragments reflect changes in expression of intact protein in the kidney, suggesting new potential mediators of diabetic nephropathy and candidate biomarkers for progressive renal function decline.

Identification of urinary soluble E-cadherin as a novel biomarker for diabetic nephropathy.

BACKGROUND: Currently, early diagnosis of diabetic nephropathy (DN) remains a major challenge. Thus, more investigations into new DN-related biomarkers are needed. METHODS: We employed urinary proteomic approach of fluorescence-based difference gel electrophoresis (DIGE) and mass spectrometry to identify novel biomarkers in urine samples, which were from type 2 diabetes patients with normoalbuminuria (DM group), microalbuminuria (DN1 group), macroalbuminuria (DN2 group) and control group (n=8 in each group). The identified biomarker was further studied by western blot in urine samples (n=6 in each group) and immunohistochemistry in renal biopsies. Besides, the urinary level of biomarker was detected and analyzed using enzyme-linked immunosorbent assay(ELISA) method (n=40 in each group). RESULTS: A novel DN-related biomarker, urinary E-cadherin, was identified by proteomic methods, which up-regulated 1.3-fold, 5.2-fold and 8.5-fold in DM, DN1 and DN2 groups compared with control group. Meanwhile, high expression of urinary soluble 80 kDa fragment of E-cadherin (sE-cadherin) was verified in DN groups by western blot. The ELISA data also demonstrated that urinary sE-cadherin-to-creatinine ratio was significantly increased in DN1 and DN2 groups versus DM group or control group (2751.5+/-164 and 5839.6+/-428 vs 721.9+/-93 or 652.7+/-87 microg/g; p<0.001). The sensitivity and specificity of urinary sE-cadherin for diagnosis of DN were calculated as 78.8% (95% CI, 74-83%) and 80% (95% CI, 65-91%). Besides, immunohistochemical stain showed that E-cadherin expression was markedly decreased in renal tubular epithelial cells of patients with DN versus healthy controls. CONCLUSIONS: Urinary sE-cadherin has a potential clinical diagnostic value for DN and E-cadherin may participate in the pathogenesis of DN.

E-cadherin tissue expression and urinary soluble forms of E-cadherin in patients with bladder transitional cell carcinoma.

OBJECTIVE: To investigate the clinical significance of E-cadherin (E-CD) expression in human bladder transitional cell carcinoma (TCC) tissue and soluble forms of E-cadherin (sE-CD) in the urine of patients with TCC. MATERIALS AND METHODS: One hundred and two specimens of bladder TCC and 10 normal bladder tissues were stained immunohistochemically with anti-E-CD monoclonal antibody. The urinary sE-CD from 59 subjects with TCC or controls was measured with enzyme-linked immunosorbent assay (ELISA). All results were analyzed statistically between groups. RESULTS: The expression of E-CD in bladder TCC correlated well with grade and stage but had no significant correlation with the size or number of the tumors. Normal expression rate of E-CD is significantly higher in primary than in recurrent tumors. The level of urinary sE-CD was higher in patients with TCC than in normal controls or patients with benign disorders of the urinary system. Urinary sE-CD levels were strongly correlated with tumor grade but showed no significant correlation with the stage, size and number of the tumors. The urinary sE-CD level is significantly higher in the recurrent group than in the primary group. CONCLUSIONS: Expression of E-CD in the tissue of TCC and the urinary level of sE-CD are very closely associated with the biological behaviors of bladder TCC.

Soluble N-cadherin in human biological fluids.

Classical cadherins such as E-, P- and N-cadherin are transmembrane proteins that mediate cell-cell adhesion, and are important in embryogenesis, maintenance of tissue integrity and cancer. Proteolytic shedding of the extracellular domain results in the generation of soluble E-, P- or N-cadherin ectodomains. Circulating soluble E- and P-cadherin have been described in the serum, and elevated levels were detected in cancer patients when compared with healthy persons. Here we report the presence of soluble N-cadherin, a 90-kD protein fragment, in the serum of both healthy persons and cancer patients, using a direct ELISA and immunoprecipitation. A correlation was found between prostate specific antigen and soluble N-cadherin, and significantly elevated levels were detected in prostate cancer follow-up patients. The N-cadherin protein is neo-expressed by carcinomas of the prostate, and is responsible for epithelial to fibroblastic transition. This is reflected by the higher concentrations of soluble N-cadherin in prostate cancer patients than in healthy persons.

Urinary levels of soluble e-cadherin in the detection of transitional cell carcinoma of the urinary bladder.

OBJECTIVE: To test the hypothesis that elevated urinary levels of soluble E-cadherin (sE-cadherin) would aid in the detection of transitional cell carcinoma (TCC) of the urinary bladder. METHODS: We performed sE-cadherin staining of one murine (MBT2) and four human (RT4, 5637, T24, and TCCSUP) bladder cancer cell lines. sE-cadherin levels were also determined in voided urine of 188 consecutive subjects at risk for TCC recurrence, 31 patients with other uro-pathologic conditions, and 10 healthy subjects using a commercially-available ELISA kit. sE-cadherin was analyzed continuously and categorically on the basis of its median distribution. RESULTS: Moderately and poorly differentiated bladder cancer cell lines had decreased cellular E-cadherin expression, whereas RT4, a well differentiated cell line, had preserved expression. All cell lines had measurable sE-cadherin levels in their conditioned media. The area under the ROC curve of sE-cadherin for the detection of TCC was 0.719 (95%CI, 0.637-0.801; p<0.001). Higher levels of sE-cadherin were associated with positive cytology results (p=0.012) and muscle invasive tumor stage (p=0.009). Urinary sE-cadherin was more sensitive, but less specific than urinary cytology for the detection of bladder TCC. In a multivariable logistic regression analysis, higher sE-cadherin and positive cytology were both associated with an increased risk of bladder TCC (p=0.048 and p<0.001, respectively). Combination of cytology and sE-cadherin allowed categorization of patients into three significantly different risk groups for bladder cancer. Adjustment of sE-cadherin for urinary creatinine levels did not affect any of the outcomes. CONCLUSIONS: Urinary level of sE-cadherin may add information to cytology in the detection of bladder TCC.

Hypermethylation of multiple genes in tumor tissues and voided urine in urinary bladder cancer patients.

PURPOSE: We aimed to investigate the methylation pattern in bladder cancer and assess the diagnostic potential of such epigenetic changes in urine. EXPERIMENTAL DESIGN: The methylation status of 7 genes (RARbeta, DAPK, E-cadherin, p16, p15, GSTP1, and MGMT) in 98 cases of bladder transitional cell carcinoma and 4 cases of carcinoma in situ was analyzed by methylation-specific PCR. Twenty-two cases had paired voided urine samples for analysis. RESULTS: In transitional cell carcinoma tumor tissues, aberrant methylation was frequently detected in RARbeta (87.8%), DAPK (58.2%), E-cadherin (63.3%), and p16 (26.5%), whereas methylation of p15 (13.3%), GSTP1 (5.1%), and MGMT (5.1%) is not common. No association between methylation status and grading or muscle invasiveness was demonstrated. In 22 paired voided urine samples of bladder cancer, methylation of DAPK, RARbeta, E-cadherin, and p16 could be detected in 45.5%, 68.2%, 59.1%, and 13.6% of the cases, respectively. The sensitivity of methylation analysis (90.9%) was higher than that of urine cytology (45.5%) for cancer detection. Methylation of RARbeta(50%), DAPK (75%), and E-cadherin (50%) was also detected in carcinoma in situ. In 7 normal urothelium samples and 17 normal urine controls, no aberrant methylation was detected except for RARbeta methylation in 3 normal urothelium samples (42.9%) and 4 normal urine samples (23.5%), respectively. CONCLUSIONS: Our results demonstrated a distinct methylation pattern in bladder cancer with frequent methylation of RARbeta, DAPK, E-cadherin, and p16. Detection of gene methylation in routine voided urine using selected markers appeared to be more sensitive than conventional urine cytology.