Comparative gene expression profiling analysis of urothelial carcinoma of the renal pelvis and bladder

Expression Profiles of Hypoxia-Related Genes of Cancers Originating from Anatomically Similar Locations Using TCGA Database Analysis

Background: Hypoxia is a well-recognized characteristic of the tumor microenvironment of solid cancers. This study aimed to analyze hypoxia-related genes shared by groups based on tumor location. Methods: A total of 9 hypoxia-related pathways from the Kyoto Encyclopedia of Genes and Genomes database or the Reactome database were selected, and 850 hypoxia-related genes were analyzed. Based on their anatomical locations, 14 tumor types were categorized into 6 groups. The group-specific genetic risk score was classified as high- or low-risk based on mRNA expression, and survival outcomes were evaluated. Results: The risk scores in the Female Reproductive group and the Lung group were internally and externally validated. In the Female Reproductive group, CDKN2A, FN1, and ITGA5 were identified as hub genes associated with poor prognosis, while IL2RB and LEF1 were associated with favorable prognosis. In the Lung group, ITGB1 and LDHA were associated with poor prognosis, and GLS2 was associated with favorable prognosis. Functional enrichment analysis showed that the Female Reproductive group was enriched in relation to cilia and skin, while the Lung group was enriched in relation to cytokines and defense. Conclusions: This analysis may lead to better understanding of the mechanisms of cancer progression and facilitate establishing new biomarkers for prognosis prediction.

An Integrated Bioinformatics Analysis towards the Identification of Diagnostic, Prognostic, and Predictive Key Biomarkers for Urinary Bladder Cancer

Simple Summary

Bladder cancer is evidently a challenge as far as its prognosis and treatment are concerned. The investigation of potential biomarkers and therapeutic targets is indispensable and still in progress. Most studies attempt to identify differential signatures between distinct molecular tumor subtypes. Therefore, keeping in mind the heterogeneity of urinary bladder tumors, we attempted to identify a consensus gene-related signature between the common expression profile of bladder cancer and control samples. In the quest for substantive features, we were able to identify key hub genes, whose signatures could hold diagnostic, prognostic, or therapeutic significance, but, primarily, could contribute to a better understanding of urinary bladder cancer biology.

Abstract

Bladder cancer (BCa) is one of the most prevalent cancers worldwide and accounts for high morbidity and mortality. This study intended to elucidate potential key biomarkers related to the occurrence, development, and prognosis of BCa through an integrated bioinformatics analysis. In this context, a systematic meta-analysis, integrating 18 microarray gene expression datasets from the GEO repository into a merged meta-dataset, identified 815 robust differentially expressed genes (DEGs). The key hub genes resulted from DEG-based protein–protein interaction and weighted gene co-expression network analyses were screened for their differential expression in urine and blood plasma samples of BCa patients. Subsequently, they were tested for their prognostic value, and a three-gene signature model, including COL3A1, FOXM1, and PLK4, was built. In addition, they were tested for their predictive value regarding muscle-invasive BCa patients’ response to neoadjuvant chemotherapy. A six-gene signature model, including ANXA5, CD44, NCAM1, SPP1, CDCA8, and KIF14, was developed. In conclusion, this study identified nine key biomarker genes, namely ANXA5, CDT1, COL3A1, SPP1, VEGFA, CDCA8, HJURP, TOP2A, and COL6A1, which were differentially expressed in urine or blood of BCa patients, held a prognostic or predictive value, and were immunohistochemically validated. These biomarkers may be of significance as prognostic and therapeutic targets for BCa.

Upper urothelial tract high-grade carcinoma: comparison of urine cytology and DNA methylation analysis in urinary samples

Numerous studies showed that bladder urothelial carcinoma and upper urothelial tract carcinoma (UTUC) display clinical and genomic similarities. In order to analyze that the same panel of biomarkers used in the diagnosis of bladder urothelial carcinoma could be suitable for early detection of UTUC, we performed a retrospective study in which we analyzed Bladder EpiCheck scores in the urinary samples obtained by selective ureteral catheterization in a high-grade UTUC cohort, correlating the results with urinary cytology and diagnostic urethral biopsies. The present study represents a retrospective analysis of 82 patients with clinically localized high-grade UTUC (60 renal pelvis UTUC, 22 ureter UTUC) who had undergone a radical nephroureterectomy (RNU) at our Urology department from June 2018 to November 2020. Before any surgical procedure, one sample of urine, obtained by selective ureteral catheterization, was collected for each patient for cytological examination, and the remaining material was stored for the Bladder EpiCheck test. Our results showed that the sensitivity of the methylation test for high-grade UTUC was about 97.4%, significantly higher than the sensitivity of urinary cytology either considering the HGUC cytological diagnosis or including in the positive cases the SHGUC cytological diagnosis (97.4% versus 59% or 70.5%). The methylation analysis of urinary samples may represent a valid tool in the diagnostic process of patients with suspected UTUC. In cases with a difficult clinical decision after upper urinary tract biopsy and cytology, the methylation test could assist in the clinical management of UTUC patients.

Molecular Characterization of Upper Tract Urothelial Carcinoma in the Era of Next-generation Sequencing: A Systematic Review of the Current Literature

CONTEXT

While upper tract urothelial carcinoma (UTUC) share histological appearance with bladder cancer (BC), the former has differences in etiology and clinical phenotype consistent with characteristic molecular alterations.

OBJECTIVE

To systematically evaluate current genomic sequencing and proteomic data examining molecular alterations in UTUC.

EVIDENCE ACQUISITION

A systematic review using PubMed, Scopus, and Web of Science was performed in December 2019 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement.

EVIDENCE SYNTHESIS

A total of 46 publications were selected for inclusion in this report, including 13 studies assessing genome-wide alterations, 18 studies assessing gene expression or microRNA expression profiles, three studies assessing proteomics, one study assessing genome-wide DNA methylation, and 14 studies evaluating distinct pathway alteration patterns. Differences between sporadic and hereditary UTUC, and between UTUC and BC, as well as molecular profiles associated with exposure to aristolochic acid are highlighted. Molecular pathways relevant to UTUC biology, such as alterations in FGFR3, TP53, or microsatellite instability, are discussed. Our findings are limited by tumor and patient heterogeneity and different platforms used in the studies.

CONCLUSIONS

Molecular events in UTUC and BC can be shared or distinct. Consequently, molecular subtypes differ according to location. Further work is needed to define the epigenomic and proteomic features of UTUC, and understand the mechanisms by which they shape the clinical behavior of UTUC.

PATIENT SUMMARY

We report the current data on the molecular alterations specific to upper tract urothelial carcinoma (UTUC), resulting from novel genomic and proteomic technologies. Although UTUC biology is comparable with that of bladder cancer, the rates and UTUC-enriched alterations support its uniqueness and the need for precision medicine strategies for this rare tumor type.

Role of Microtubule-Associated Protein 1b in Urothelial Carcinoma: Overexpression Predicts Poor Prognosis

We sought to examine the relationship between microtubule-associated proteins (MAPs) and the prognosis of urothelial carcinoma by assessing the microtubule bundle formation genes using a reappraisal transcriptome dataset of urothelial carcinoma (GSE31684). The result revealed that microtubule-associated protein 1b (MAP1B) is the most significant upregulated gene related to cancer progression. Real-time reverse-transcription polymerase chain reaction was used to measure MAP1B transcription levels in urothelial carcinoma of the upper tract (UTUC) and the bladder (UBUC). Immunohistochemistry was conducted to detect MAP1B protein expression in 340 UTUC and 295 UBUC cases. Correlations of MAP1B expression with clinicopathological status, disease-specific survival, and metastasis-free survival were completed. To assess the oncogenic functions of MAP1B, the RTCC1 and J82 cell lines were stably silenced against their endogenous MAP1B expression. Study findings indicated that MAP1B overexpression was associated with adverse clinical features and could independently predict unfavorable prognostic effects, indicating its theranostic value in urothelial carcinoma.

Arsenic exposure is associated with significant upper tract urothelial carcinoma health care needs and elevated mortality rates

PURPOSE

The aim of the study was to assess upper tract urothelial carcinoma (UTUC) health care needs and specific mortality rates in an arsenic-exposed region in Northern Chile and compare them to those of the rest of the country.

MATERIAL AND METHODS

Arsenic levels of drinking water were correlated with UTUC hospital discharges and cancer-specific mortality rates. Mortality and hospital admission rate ratios were estimated using a Poisson regression model.

RESULTS

There were 257 UTUC-specific deaths in Chile between 1990 and 2016; 81 (34%) of them occurred in Antofagasta, where only 3.5% of the population lives. The peak mortality rate observed in Antofagasta was 2.15/100,000 compared to 0.07/100,000 in the rest of the country. Mortality in the exposed region was significantly higher when compared to the rest of the country (MRR 17.6; 95%CI: 13.5-22.9). The same trend was observed for UTUC hospital discharges (RR 14.8; 95%CI: 11.5-19.1).

CONCLUSION

Even stronger than for bladder cancer, exposure to arsenic is related to a significant need for UTUC health care and high mortality rates, even 25 years after having controlled arsenic levels in drinking-water. Awareness of this ecologic factor in these affected regions is therefore mandatory.

Downregulation of the cytochrome P450 4B1 protein confers a poor prognostic factor in patients with urothelial carcinomas of upper urinary tracts and urinary bladder

The objective of this study was to examine the expression level of cytochrome P450 4B1 (CYP4B1) protein and its clinical significance in specimens from patients with urothelial carcinomas (UC) including upper tract urothelial carcinoma (UTUC, n = 340) and urinary bladder urothelial carcinoma (UBUC, n = 295). Data mining on public domains identified five potential candidate transcripts which were downregulated in advanced UBUCs, indicating that it might implicate in UC progression. Immunohistochemistry was performed to analyze the CYP4B1 protein levels on 635 tissues from UC patients retrospectively. Immunoexpression of CYP4B1 was further estimated using the H-score method. Correlations between CYP4B1 H-score and important clinicopathological factors, as well as the significance of CYP4B1 expression level for disease-specific and metastasis-free survivals were evaluated. In UTUCs and UBUCs, 118 (34.7%) and 92 (31.2%) patients, respectively, were identified to be of CYP4B1 downregulation. The CYP4B1 expression level was found to be associated with several clinicopathological factors and patient survivals. Downregulation of CYP4B1 protein was correlated to advanced primary tumor (p < 0.001), nodal metastasis (p < 0.001), high histological grade (p = 0.001), vascular invasion (p < 0.001), perineural invasion (p = 0.017) and mitotic rate (p = 0.036) in UTUCs and/or UBUCs. Low CYP4B1 protein level independently predicted inferior disease-specific (p = 0.009; p < 0.001) and metastasis-free (p = 0.035; p < 0.001) survivals in UTUC and UBUC patients. Our findings showed that downregulation of CYP4B1 protein level is an independent unfavorable prognosticator. Loss of the CYP4B1 gene expression may play an important role in UC progression.

[Instillation therapies for urothelial carcinoma of the upper urinary tract]

Traditionally, urothelial carcinoma of the upper urinary tract was a clear indication for radical nephroureterectomy with bladder cuff excision. It has been shown that in well-selected patients and depending on tumor stage, a kidney-sparing approach can be pursued with good oncological outcome and equivalent to the radical approach. The prevention of local and bladder recurrences is an important factor. Instillation therapies with bacillus Calmette-Guérin and/or mitomycin C have been successfully used to this end. Due to the low incidence of upper tract urothelial cancer and due to the usually retrospective nature of existing literature, however, data is limited. In this article, we provide a review of the indication, technical execution and results of instillation therapies of the upper urinary tract.

Detection of urothelial carcinoma, upper tract urothelial carcinoma, bladder carcinoma, and urothelial carcinoma with gross hematuria using selected urine-DNA methylation biomarkers: A prospective, single-center study

INTRODUCTION

Hematuria is the most common symptom of urothelial carcinomas (UC) but is often idiopathic. Cystoscopy is expensive which involves considerable patient discomfort, and conventional urine cytology for noninvasive UC detection and disease monitoring suffers from poor sensitivity. We aim to evaluate the performance of genes selected from a previous study in detecting UC, especially among patients with gross hematuria, as well as upper tract urothelial carcinoma (UTUC) and bladder carcinoma separately, in voided urine samples.

METHODS

Using methylation-specific polymerase chain reaction, we examined the promoter methylation status of 10 genes in voided urine samples among 473 patients at our institution, including 217 UC patients and 256 control subjects.

RESULTS

The final combination of VIM, CDH1, SALL3, TMEFF2, RASSF1A, BRCA1, GDF15, and ABCC6 identified UC with a sensitivity of 0.83 and a specificity of 0.60. Additionally, a panel of selected genes (CDH1, HSPA2, RASSF1A, TMEFF2, VIM, and GDF15) identified UTUC with a sensitivity of 0.82 and a specificity of 0.68, while a panel of selected genes (VIM, RASSF1A, GDF15, and TMEFF2) identified bladder carcinoma with a sensitivity of 0.82 and a specificity of 0.53. Remarkably, a different panel (CDH1, SALL3, THBS1, TMEFF2, VIM, and GDF15) identified UC in patients with gross hematuria with 0.89 sensitivity and 0.74 specificity, and sensitivity (0.91) and specificity (0.92) could be achieved when cytology was included.

CONCLUSIONS

The selected urine-DNA methylation biomarkers are reliable, noninvasive, and cost-effective diagnostic tools for bladder carcinoma and UTUC, especially among patients with gross hematuria.

Functional analysis of gene expression profiling-based prediction in bladder cancer

The present study aimed to analyze the modification of gene expression in bladder cancer (BC) by identifying significant differentially expressed genes (DEGs) and functionally assess them using bioinformatics analysis. To achieve this, two microarray datasets, GSE24152 (which included 10 fresh tumor tissue samples from urothelial bladder carcinoma patients and 7 benign mucosa samples from the bladder), and GSE42089 (which included 10 tissues samples from urothelial cell carcinoma patients and 8 tissues samples from the normal bladder), were downloaded from the Gene Expression Omnibus database for further analysis. Differentially expressed genes (DEGs) were screened between benign the mucosa and control groups in GSE24152 and GSE42089 datasets. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analysis were performed on overlapping DEGs identified in GSE24152 and GSE42089. Protein-protein interaction (PPI) networks and sub-networks were then constructed to identify key genes and main pathways. GO terms analysis was also performed for the selected clusters. In total, 1,325 DEGs in GSE24152 and 647 DEGs in GSE42089 were screened, in which 619 common DEGs were identified. The DEGs were mainly enriched in pathways and GO terms associated with mitotic and chromosome assembly, including nucleosome assembly, spindle checkpoint and DNA replication. In the interaction network, progesterone receptor (PGR), MAF bZIP transcription factor G (MAFG), cell division cycle 6 (CDC6) and members of the minichromosome maintenance family (MCMs) were identified as key genes. Histones were also considered to be significant factors in BC. Nucleosome assembly and sequence-specific DNA binding were the most significant clustered GO terms. In conclusion, the DEGs, including PGR, MAFG, CDC6 and MCMs, and those encoding the core histone family were closely associated with the development of BC via pathways associated with mitotic and chromosome assembly.

Micro-brushing-based technique to gain fresh urothelial cells for gene expression analysis

The gold standard of saving fresh tissue in liquid nitrogen has some serious disadvantages in that this process is not available in daily medical routine practices even in many tumor centers. Our approach of a new minimally invasive technique is obtaining urothelial cells via micro-brushing the urinary bladder on the occasion of urological routine methods such as transurethral resection (TUR). Urothelial cells were obtained from 25 patients via two different micro-brushes from tumor tissue and from macroscopically healthy tissue during TUR. These cells were immediately transferred into RNA stabilization reagent and stored at -20°C. Later, mRNA was isolated, transcribed into cDNA, and amplified. cDNA was stored at -20°C until analysis. The mean RNA quantity was 99.5 ng/μl from tumor tissues and 66.3 ng/μl from macroscopically tumor-free tissue, enabling a considerable number of analyses. The quality of the gained cDNA allowed semi-quantitative PCR analysis of GSTM1 expression as well as quantitative PCR analysis of c-Myc expression. The new technique presents several important advantages. First, staging and grading of the stained tumor sample can be examined immediately, whereas fresh frozen sample is not examined until some days later. Further, this method can be applied in hospitals with no access to liquid nitrogen or without capability to provide an additional examination of frozen tumor sample by a pathologist. This presented minimally invasive method enables investigation of gene expression in the urinary bladder without disadvantages of the need for storage of fresh tissues in liquid nitrogen.

The prognostic and diagnostic value of circulating tumor cells in bladder cancer and upper tract urothelial carcinoma: a meta-analysis of 30 published studies

There are inconsistent conclusions in the association between circulating tumor cells (CTCs) and urothelial cancer (UC). We performed a meta-analysis to assess the prognostic and diagnostic value of CTCs in UC. We search Medline, Embase and Web of science for relevant studies. The study was set up according to the inclusion/exclusion criteria. 30 published studies with a total of 2161 urothelial cancer patients were included. Meta-analysis showed that CTC-positive was significantly associated with tumor stage (≤ II vs III, IV) (OR = 4.60, 95% CI: 2.34-9.03), histological grade (I, II vs III) (OR = 2.91, 95% CI: 1.92-4.40), metastasis (OR = 5.12, 95% CI: 3.47-7.55) and regional lymph node metastasis (OR = 2.47, 95% CI: 1.75-3.49). It was also significantly associated with poor overall survival (OS) (HR = 3.98, 95% CI: 2.20-7.21), progression/disease-free survival (PFS/DFS) (HR = 2.22, 95% CI: 1.80-2.73) and cancer-specific survival (CSS) (HR = 5.18, 95% CI: 2.21-12.13). Overall sensitivity and specificity of CTC detection assays were 0.35 (95% CI: 0.28-0.43) and 0.97 (95% CI: 0.92-0.99) respectively. In summary, our meta-analysis suggests that the presence of CTCs in the peripheral blood is an independent predictive indicator of poor outcomes for urothelial cancer patients. It can also be used as a noninvasive method for the confirmation of cancer diagnosis. More studies are required to further explore the role of this marker in clinical practice.

ASP5878, a selective FGFR inhibitor, to treat FGFR3-dependent urothelial cancer with or without chemoresistance

FGF/FGFR gene aberrations such as amplification, mutation and fusion are associated with many types of human cancers including urothelial cancer. FGFR kinase inhibitors are expected to be a targeted therapy for urothelial cancer harboring FGFR3 gene alternations. ASP5878, a selective inhibitor of FGFR1, 2, 3 and 4 under clinical investigation, selectively inhibited cell proliferation of urothelial cancer cell lines harboring FGFR3 point mutation or fusion (UM-UC-14, RT-112, RT4 and SW 780) among 23 urothelial cancer cell lines. Furthermore, ASP5878 inhibited cell proliferation of adriamycin-resistant UM-UC-14 cell line harboring MDR1 overexpression and gemcitabine-resistant RT-112 cell line. The protein expression of c-MYC, an oncoprotein, in gemcitabine-resistant RT-112 cell line was higher than that in RT-112 parental cell line and ASP5878 decreased the c-MYC expression in both RT-112 parental and gemcitabine-resistant RT-112 cell lines. Once-daily oral administration of ASP5878 exerted potent antitumor activities in UM-UC-14, RT-112 and gemcitabine-resistant RT-112 xenograft models without affecting body weight. These findings suggest that ASP5878 has the potential to be an oral targeted therapy against urothelial cancer harboring FGFR3 fusion or FGFR3 point mutation after the acquisition of gemcitabine- or adriamycin-resistance.

MicroRNA promoter methylation: a new tool for accurate detection of urothelial carcinoma

Background:

Urothelial carcinoma (UC) is the most common cancer affecting the urinary system, worldwide. Lack of accurate early detection tools entails delayed diagnosis, precluding more efficient and timely treatment. In a previous study, we found that miR-129-2 and miR-663a were differentially methylated in UC compared with other genitourinary tract malignancies. Here, we evaluated the diagnostic performance of those microRNAs in urine.

Methods:

Promoter methylation levels of miR-129-2 and miR-663a were assessed, using real-time quantitative methylation-specific PCR, in UC tissue samples (using normal urothelium as control) and, subsequently, in urine samples from UC and other genitourinary malignancies. Diagnostic and prognostic performances were evaluated by receiver operator characteristics curve and survival analyses, respectively.

Results:

Promoter methylation levels of both microRNAs were significantly higher in UC tissue samples compared with normal urothelium. In urine, the assay was able to distinguish UC from other genitourinary tract carcinomas with 87.7% sensitivity and 84% specificity, resulting in 85.85% overall accuracy.

Conclusions:

This panel of miRNAs promoter methylation accurately detects UC in urine, comparing well with other promising epigenetic-based biomarkers. This may constitute the basis for a non-invasive assay to detect UC.

Downregulation of RNF128 Predicts Progression and Poor Prognosis in Patients with Urothelial Carcinoma of the Upper Tract and Urinary Bladder

Background: The TP53 tumor suppressor gene plays a crucial role in the carcinogenesis of many malignancies, including urothelial carcinoma (UC). Overexpression of p53 is associated with poor prognosis in UC. Recently, RING finger protein 128 (RNF128) was shown to be involved in p53-induced apoptosis, forming a negative feedback loop. However, the significance of RNF128 in patients with UC remains unknown. In this study, our aim was to evaluate the expression of RNF128 in UC and to assess its predictive and prognostic value in a well-established cohort. Methods: Through data mining from a published transcriptome (GSE31684), RNF128 was identified as the most differentially expressed gene in UC among those associated with negative regulation of the cytokine biosynthetic process (GO:0042036). Its immunoexpression was further evaluated using the H-scores of 340 patients with upper urinary tract UC (UTUC) and 295 with urinary bladder UC (UBUC). The scores were correlated with clinicopathological features, disease-specific survival (DSS) and metastasis-free survival (MeFS). We also used Western blot analysis to evaluate RNF128 protein expression in human urothelial cell (HUC) lines. Results: Downregulation of RNF128 expression was significantly associated with advanced pT stage (p<0.001), high histological grade (UTUC, p<0.001; UBUC, p=0.035), nodal metastasis (UTUC, p<0.001; UBUC, p=0.001), vascular invasion (UTUC, p<0.001; UBUC, p=0.008) and high mitotic rate (UTUC, p=0.003; UBUC, p=0.023). Low expression of RNF128 was an adverse prognosticator for DSS (UTUC, p<0.0001; UBUC, p<0.0001) and MeFS (UTUC, p<0.0001; UBUC, p=0.0002). Moreover, low expression was predictive of poor DSS (UTUC, p=0.006; UBUC, p=0.003) and MeFS (UTUC, p=0.009; UBUC, p=0.036) in multivariate comparisons. Western blot analysis showed that the RNF128 protein was downregulated in invasive urothelial cancer cell lines. Conclusion: Our findings showed that downregulation of RNF128 was correlated with cancer invasiveness and metastasis as well as reduced survival in patients with UTUC and UBUC, identifying RNF128 as a prognostic factor in UC.

CEBPD amplification and overexpression in urothelial carcinoma: a driver of tumor metastasis indicating adverse prognosis

The molecular aberrations responsible for the progression of urothelial carcinoma (UC) remain largely obscure. To search candidate driver oncogenes in UC, we performed array-based genomic hybridization (aCGH) on 40 UBUC samples. Amplification of 8q11.21 was preferentially identified in patients who developed disease-specific death (53.8%) and distal metastasis (50.0%) but was barely detected in non-eventful cases (3.7% and 0%, respectively). In order to quantify the expression of candidate genes harbored in 8q11.21, laser-capture microdissection coupled with RT-PCR was performed on 32 of the 40 cases submitted to aCGH. With this, we identified CEBPD mRNA expression as most significantly associated with gains of 8q11.21, suggesting amplification-driven expression. By performing CEBPD-specific FISH and immunohistochemistry on 295 UBUCs, we confirmed CEBPD amplification (21.3%) and overexpression (29.8%) were strongly related to each other (p<0.001). Moreover, both were associated with adverse clinicopathologic features and worse outcomes. Furthermore, the clinical significance of CEBPD expression was also confirmed in an independent cohort comprised of 340 UCs from the upper urinary tract. Interestingly, CEBPD knockdown suppressed cell proliferation, migration and, most significantly, cell invasion ability in UC cells. The latter phenotype is attributed to downregulation of MMP2 as identified by RT2 Profiler PCR array. Moreover, expression of CEBPD significantly enhanced MMP2 expression and transcriptional activation by directly binding to its promoter region, as confirmed by promoter reporter assay and chromatin immunoprecipitation assay. Conclusively, CEBPD amplification is a mechanism driving increased mRNA and protein expression that confers aggressiveness in UC through MMP2-mediated cell invasiveness.

Prognostic Impact of Thrombospodin-2 (THBS2) Overexpression on Patients with Urothelial Carcinomas of Upper Urinary Tracts and Bladders

Purpose: Urothelial carcinoma (UC) is a type of tumor, especially of the urinary bladder, that affects people worldwide. Clarification of its detailed tumor biology and discovery of potential targets for developing treatment strategies are imperative because of frequent recurrences and poor prognosis of advanced UCs. By data mining a published dataset of UC of bladder (UCB) transcriptome (GSE31684) from Gene Expression Omnibus, National Center of Biotechnology Information (GEO, NCBI), we identified that THBS2 was the most significantly upregulated gene among those related to structural molecule activity (GO:0005198). Therefore, we evaluated the clinical significance and prognostic impact of thrombospondin-2 (THBS2) protein, A.K.A. TSP2, which encoded by THBS2 gene.

Materials and Methods: THBS2 immunostaining was performed in 340 UCs of upper urinary tract (UC-UUTs) and 295 UCBs; subsequently, both groups were dichotomized into high- and low-expression subgroups. Moreover, statistical analyses were performed to correlate the association between THBS2 expression and clinicopathological parameters with two survival indexes: disease-specific survival (DSS) and metastasis-free survival (MeFS).

Results: High THBS2 immunoexpression was significantly associated with advanced primary tumor status, nodal metastasis, and vascular invasion in both UC-UUT and UCB groups (all P ≤ .001). In addition, THBS2 overexpression was linked to adverse DSS and MeFS in univariate analyses and served as an independent prognosticator indicating poor outcomes in both groups in multivariate analyses.

Conclusion: THBS2 may play a crucial role in UC progression and may be a novel prognostic marker. Additional investigations to elucidate the molecular pathway are necessary for developing potential THBS2-targeted therapies for UCs.

Complement Component 1, s Subcomponent Overexpression is an Independent Poor Prognostic Indicator in Patients with Urothelial Carcinomas of the Upper Urinary Tract and Urinary Bladder

Purpose: Urothelial carcinoma of the urinary bladder and upper tract is prevalent. By subjecting a documented transcriptome data set of urothelial carcinoma of bladder (GSE31684) to data mining and focusing on genes linked to peptidase activity (GO:0008233), we recognized C1S as the most significantly upregulated gene related to an advanced tumor status and metastasis. We subsequently analyzed the association of both C1S mRNA and its encoded protein expression with the clinical and pathological significance.

Materials and Methods: We used real-time reverse transcription polymerase chain reaction to detect C1S transcription levels in 20 cases each of urothelial carcinoma of bladder and upper tract. An immunohistochemical stain was conducted to determine C1s protein expression levels in patients with urothelial carcinoma of upper tract (n = 340) and urinary bladder (n = 295). Furthermore, we examined the correlation of C1s expression with clinicopathological characteristics, disease-specific survival, and metastasis-free survival.

Results: C1S transcription levels were significantly high in patients with advanced-stage tumors of both groups (all P < .05). Immunohistochemical analysis revealed that C1s expression levels were significantly associated with adverse clinicopathological parameters in both groups of urothelial carcinoma (all P < .05). C1s overexpression predicted poor disease-specific and metastasis-free survival rates for both urothelial carcinoma groups in the univariate analysis, and it was also an independent prognostic factor in the multivariate analysis (all P < .05).

Conclusions: C1s may play a pivotal role in urothelial carcinoma progress and can represent a vital prognostic marker and a promising new therapeutic target in urothelial carcinoma.

CSF2 Overexpression Is Associated with STAT5 Phosphorylation and Poor Prognosis in Patients with Urothelial Carcinoma

Background: Urothelial carcinoma (UC) commonly occurs in the urinary bladder (UB) and rarely in upper the upper urinary tract (UT). Its molecular pathogenesis, however, remains obscure. Though the constitutive phosphorylation of Signal Transducer and Activator of Transcription 5 (STAT5) is an important part of carcinogenesis generally, researchers have not systematically investigated this process specifically in relation to UC. The present study addresses this gap. Through data mining a published transcriptomic database of UBUCs (GSE32894), it identified Colony Stimulating Factor 2 (CSF2) as the stepwise upregulated gene of much significance among those related to the positive regulation of tyrosine phosphorylation of STAT5 (GO:0042523). Since the phosphorylation of STAT5, a key process in the development of UC, is closely associated with CSF2, we then examine CSF2 transcript and protein expression, justifying their association with clinicopathological features and survival in our well-established cohort of patients with UC.

Design: Laser capture microdissection in conjunction with real-time qRT-PCR are used to detect CSF2 transcript levels in 24 UBUCs and 6 non-tumor urothelium samples. We then used the H-score method to evaluate the immunohistochemistry in order to determine CSF2 protein expression in 296 UBUCs and 340 UTUCs, respectively. After correlating protein expression status with key clinicopathological features, the prognostic significance of CSF2 protein expression was determined for disease-specific survival (DSS) and metastasis-free survival (MeFS).

Results: We exclusively detected the CSF2 transcript, which was stepwise upregulated in tumor lesions (p=0.010). In both groups of UC we found overexpression of CSF2 significantly related to incremental pT status (UTUC, p=0.011; UBUC, p<0.001), as well as with perineural invasion (UTUC, p=0.002; UBUC, p=0.001). Univariate analysis found a close correlation between CSF2 overexpression and unfavorable prognosis for both DSS (UTUC, p=0.0001; UBUC, p<0.0001) and MeFS (UTUC, p=0.0001; UBUC, p=0.0002). High expression of CSF2 still remained prognostically for DSS (UTUC, p=0.015; UBUC, p=0.004) and MeFS (UTUC, p=0.008; UBUC, p=0.027) in multivariate comparison.

Conclusion: Our data showed that overexpression of CSF2 was inferred in advanced disease status and poor clinical outcomes for both UTUC and UBUC patients, suggesting that CSF2 may serve as an important prognosticator and a potential therapeutic target of UC.

Necdin Overexpression Predicts Poor Prognosis in Patients with Urothelial Carcinomas of the Upper Urinary Tract and Urinary Bladder

BACKGROUND AND AIMS

Oncogenesis is a multistep process, resulting from the accumulations of multiple mutations. Of these mutations, self-sufficiency in growth signals, i.e., disruption of cell growth regulation, is the first episode. Nonetheless, the genes associated with cell growth dysregulation have seldom been systematically evaluated in either urothelial carcinomas of upper urinary tract (UTUC) or urothelial carcinomas of urinary baldder (UBUC). By data mining a published transcriptomic dataset of UBUCs (GSE31684), we identified the NDN gene as one of the most significant of those associated with the regulation of cell growth and found this gene is associated with advanced tumor status and metastatic disease (GO:0001558). Accordingly, we analyzed NDN transcript and protein expression with their clinicopathological significance.

MATERIALS AND METHODS

We used real time RT-PCR to detect NDN transcript levels in 27 UTUCs and 27 UBUCs, respectively. Immunohistochemical study was performed to determine NDN protein (a.k.a. Necdin) expression evaluated by H-score method in 340 UTUCs and 295 UBUCs. NDN expression was further correlated with clinicopathological features and disease-specific survival (DSS) and metastasis-free survival (MeFS).

RESULTS

NDN transcriptional level was significantly higher in UCs of both sites with stepwise more advanced pT statuses. Through immunohistochemistry, we found NDN protein expression was significantly associated with adverse clinicopathological parameters, e.g., advanced pT status, nodal metastasis, high grade histological patterns, and frequent mitotses (all P<0.05). In univariate analysis, NDN overexpression not only predicted worse DSS and MeFS in both the UTUC and UBUC groups, it also served as an independent prognostic factor for DSS and MeFS in multivariate analysis (all P<0.05).

CONCLUSIONS

NDN may play an important role in tumor progression in UC and could serve as a prognostic biomarker and a potential novel therapeutic target in UC.

Comparative Gene Expression Analyses Identify Luminal and Basal Subtypes of Canine Invasive Urothelial Carcinoma That Mimic Patterns in Human Invasive Bladder Cancer

More than 160,000 people are expected to die from invasive urothelial carcinoma (iUC) this year worldwide. Research in relevant animal models is essential to improving iUC management. Naturally-occurring canine iUC closely resembles human iUC in histopathology, metastatic behavior, and treatment response, and could provide a relevant model for human iUC. The molecular characterization of canine iUC, however, has been limited. Work was conducted to compare gene expression array results between tissue samples from iUC and normal bladder in dogs, with comparison to similar expression array data from human iUC and normal bladder in the literature. Considerable similarities between enrichment patterns of genes in canine and human iUC were observed. These included patterns mirroring basal and luminal subtypes initially observed in human breast cancer and more recently noted in human iUC. Canine iUC samples also exhibited enrichment for genes involved in P53 pathways, as has been reported in human iUC. This is particularly relevant as drugs targeting these genes/pathways in other cancers could be repurposed to treat iUC, with dogs providing a model to optimize therapy. As part of the validation of the results and proof of principal for evaluating individualized targeted therapy, the overexpression of EGFR in canine bladder iUC was confirmed. The similarities in gene expression patterns between dogs and humans add considerably to the value of naturally-occurring canine iUC as a relevant and much needed animal model for human iUC. Furthermore, the finding of expression patterns that cross different pathologically-defined cancers could allow studies of dogs with iUC to help optimize cancer management across multiple cancer types. The work is also expected to lead to a better understanding of the biological importance of the gene expression patterns, and the potential application of the cross-species comparisons approach to other cancer types as well.

Molecular Analysis of Upper Tract and Bladder Urothelial Carcinoma: Results from a Microarray Comparison

Introduction

Prior studies have shown genetic similarities between upper tract and bladder urothelial carcinoma. However, upper tract urothelial carcinoma tends to be higher grade than bladder urothelial carcinoma and tends to form in patients with certain familial conditions (e.g. Lynch Syndrome), indicating there may be unique biologic processes in these tumors. The purpose of this study was to evaluate the differences in gene expression between upper tract and bladder urothelial carcinoma using microarray data.

Design, Setting, Participants

A search of publicly available microarray datasets identified a clinically annotated dataset of 12 upper tract and 20 bladder urothelial carcinoma specimens. Gene expression analysis of data derived from the Affymetrix HGU133Plus2 chip was performed. Bioconductor packages were used to evaluate clustering, differential gene expression, pathways relevant to oncology, and a basal/luminal signature in upper tract versus bladder urothelial carcinoma.

Results

When separated by pathologic T stage, there was evidence of differential clustering among pT3 tumors and significant gene expression differences in 81 genes. Pathway analysis revealed differences in HGF and TNF signaling pathways. Upper tract tumors tended to have high expression of genes associated with a luminal subtype. One of the genes most highly expressed in upper tract tumors, SLITRK6, is the target of an antibody drug conjugate (AGS15E) currently in phase I clinical trials.

Conclusions

This study provides evidence for molecular differences between upper tract and bladder urothelial carcinoma, some of which contribute to oncologic-relevant pathways. Upper tract tumors tended to express genes consistent with a luminal subtype. We also identify a marker, SLITRK6, as a potential target for patients with advanced upper tract urothelial carcinoma.

Identification of circulating microRNA signatures for upper tract urothelial carcinoma detection

The involvement of circulating microRNAs (miRNAs) in cancer and their potential as diagnostic and prognostic biomarkers are becoming increasingly known. However, the significance of circulating miRNAs in upper tract urothelial carcinoma (UTUC) has remained to be investigated. The present study performed a genome‑wide serum miRNA analysis using a deep sequencing platform for initial screening. Subsequently, serum samples of 46 UTUC patients and 30 cancer‑free individuals with hematuria were subjected to a quantitative reverse‑transcription polymerase chain reaction analysis. The expression of thirteen miRNAs (miR‑664a‑3p, miR‑423‑5p, miR‑431‑5p, miR‑191‑5p, miR‑92a‑3p, miR‑22‑3p, miR‑26a‑5p, miR‑33b‑3p, miR‑16‑5p, let‑7a‑5p, let‑7b‑5p, let‑7f‑5p and let‑7c) was significantly different in serum from UTUC patients compared with that in control samples. Receiver operator characteristic analysis showed that 10 miRNAs (miR‑664a‑3p, miR‑431‑5p, miR‑423‑5p, miR‑191‑5p, miR‑33b‑3p, miR‑26a‑5p, miR‑22‑3p, miR‑16‑5p, let‑7b‑5p and let‑7c) had the potential to distinguish individuals with UTUC from the controls (areas under the curve >0.8). The present study provided the first evidence for the potential use of circulating miRNAs as biomarkers for UTUC diagnosis, which remains to be verified by further studies.

Cytoplasmatic and Nuclear YAP1 and pYAP1 Staining in Urothelial Bladder Cancer

INTRODUCTION

Yes-associated protein 1 (YAP1), the nuclear effector of the Hippo pathway, plays an important role in many tumor entities. We evaluated staining and clinical significance of YAP1 and phosphorylated YAP1 (pYAP1) in urothelial bladder cancer (BCA).

MATERIALS AND METHODS

We used a tissue micorarray with samples of patients with muscle-invasive bladder cancer (MIBC, n = 192), non-muscle-invasive bladder cancer (NMIBC, n = 192) and normal urothelial bladder tissue (CTRL, n = 38) to determine the immunhistochemical staining of YAP1 and pYAP1. Cytoplasmatic and nuclear levels were evaluated. The t test was used for comparative analysis. Overall survival and progression-free survival were evaluated by Kaplan-Meier estimates and the Cox proportional hazard regression model.

RESULTS

Nuclear YAP1 as well as cytoplasmatic pYAP1 levels were higher in CTRL than in BCA, whereby both--NMIBC and MIBC--had lower levels than CTRL. Among patients with MIBC, cytoplasmatic YAP1 and pYAP1 staining decreased with advanced stage. YAP1 and pYAP1 staining did not correlate with the recurrence rate, progression-free, cancer-specific or overall survival.

CONCLUSIONS

Immunhistochemical staining and subcellular localization of YAP1 and pYAP1 are different for BCA, NMIBC, MIBC and CTRL, indicating that the Hippo pathway is involved in urothelial carcinogenesis.

HAS3 underexpression as an indicator of poor prognosis in patients with urothelial carcinoma of the upper urinary tract and urinary bladder

Via data mining a published transcriptomic database of UBUC (GSE31684), we discovered hyaluronan synthase-3 (HAS3) as the most significant gene stepwise downregulated from early tumorigenesis to progression among those associated with hyaluronan synthase activity (GO:0050501). We consequently analyzed HAS3 protein expression and their association with clinicopathological factors and survival in our well-characterized cohort of urothelial carcinoma of upper urinary tract (UTUC) and urinary bladder (UBUC). HAS3 expression was assessed by immunohistochemistry and evaluated by using H score method in 295 UBUCs and 340 UTUCs, respectively. HAS3 protein expression statuses were further correlated with clinicopathological parameters and evaluated the prognostic significance for disease-specific survival (DSS) and metastasis-free survival (MeFS). HAS3 protein underexpression was significantly associated with advanced pT status, nodal metastasis, high histological grade, vascular invasion, and frequent mitoses in both groups of UCs. HAS3 underexpression not only predicted poorer DSS and MeFS with univariate analysis, but also indicated dismal DSS and MeFS in multivariate analysis. HAS3 underexpression is associated with advanced tumor stage and adverse pathological features, as well as implies inferior clinical outcomes for both groups of patients with UTUCs and UBUCs, suggesting its critical role in tumor progression in UCs and may serve as a prospective prognostic biomarker and a novel therapeutic target in UCs.

CDCA5 overexpression is an indicator of poor prognosis in patients with urothelial carcinomas of the upper urinary tract and urinary bladder

AIMS

Urothelial carcinoma (UC) is the most common tumor involving upper urinary tract (UTUC) and urinary bladder (UBUC) whose molecular survival determinants remains obscured. By computerizing a public transcriptomic database of UBUCs (GSE32894), we identified cell division cycle associated 5 (CDCA5) as the most significantly upregulated gene among those associated with G1-S transition of the mitotic cell cycle (GO:0000082). We therefore analyzed the clinicoptaological significance of CDCA5 expression in our well-characterized UC cohort.

METHODS AND RESULTS

Quantigene assay was used to detect CDCA5 transcript levels in 36 UTUCs and 30 UBUCs. We used immunohistochemistry evaluated by H-scores to determine CDCA5 protein expression in 295 UBUCs and 340 UTUCs, respectively. CDCA5 expression was further correlated with clinicopathological features and disease-specific survival (DSS) and metastasis-free survival (MeFS). For both groups of UCs, increments of CDCA5 transcript levels were associated with higher pT status, CDCA5 protein overexpression was also significantly associated with advanced pT status, nodal metastasis, high histological grade, vascular invasion, and frequent mitoses. CDCA5 overexpression was predictive for worse DSS and MeFS in univariate and multivariate analysis.

CONCLUSIONS

CDCA5 overexpression is associated with advanced clinical features of UC, suggesting its potential value as a prognostic biomarker and a novel therapeutic target.

GPX2 underexpression indicates poor prognosis in patients with urothelial carcinomas of the upper urinary tract and urinary bladder

PURPOSE

Oxidative stress is believed to be one of the important etiologies in carcinogenesis that has not been systemically investigated in urothelial carcinoma (UC). Through data mining from a published transcriptomic database of UC of urinary bladders (UBUCs) (GSE31684), glutathione peroxidase 2 (GPX2) was identified as the most significant downregulated gene among those response to oxidative stress (GO:0006979). We therefore analyze GPX2 transcript and protein expressions and its clinicopathological significance.

METHODS

Real-time RT-PCR assay was used to detect GPX2 mRNA level in 20 fresh UBUC specimens. Immunohistochemistry was used to determine GPX2 protein expression in 340 urothelial carcinomas of upper tracts (UTUCs) and 295 UBUCs with mean/median follow-up of 44.7/38.9 and 30.8/23.1 months, respectively. Its expression status was further correlated with clinicopathological features and evaluated for its impact on disease-specific survival and metastasis-free survival (MeFS).

RESULTS

Decrease in GPX2 transcript level was associated with both higher pT and positive nodal status in 20 UBUCs (all p < 0.05). GPX2 protein underexpression was also significantly associated with advanced pT status, nodal metastasis, high histological grade, vascular invasion, and frequent mitoses in both groups of UCs (all p < 0.05). GPX2 underexpression not only predicted dismal DDS and MeFS at univariate analysis, but also implicated worse DDS (UTUC, p = 0.002; UBUC, p = 0.029) and MeFS (UTUC, p = 0.001; UBUC, p = 0.032) in multivariate analysis.

CONCLUSIONS

GPX2 underexpression is associated with advanced tumor status and implicated unfavorable clinical outcome of UCs, suggesting its role in tumor progression and may serve as a theranostic biomarker of UCs.

Contralateral upper tract urothelial carcinoma after nephroureterectomy: the predictive role of DNA methylation

Background

Aberrant methylation of genes is one of the most common epigenetic modifications involved in the development of urothelial carcinoma. However, it is unknown the predictive role of methylation to contralateral new upper tract urothelial carcinoma (UTUC) after radical nephroureterectomy (RNU). We retrospectively investigated the predictive role of DNA methylation and other clinicopathological factors in the contralateral upper tract urothelial carcinoma (UTUC) recurrence after radical nephroureterectomy (RNU) in a large single-center cohort of patients.

Methods

In a retrospective design, methylation of 10 genes was analyzed on tumor specimens belonging to 664 consecutive patients treated by RNU for primary UTUC. Median follow-up was 48 mo (range: 3–144 mo). Gene methylation was accessed by methylation-sensitive polymerase chain reaction, and we calculated the methylation index (MI), a reflection of the extent of methylation. The log-rank test and Cox regression were used to identify the predictor of contralateral UTUC recurrence.

Results

Thirty (4.5%) patients developed a subsequent contralateral UTUC after a median follow-up time of 27.5 (range: 2–139) months. Promoter methylation for at least one gene promoter locus was present in 88.9% of UTUC. Fewer methylation and lower MI (P = 0.001) were seen in the tumors with contralateral UTUC recurrence than the tumors without contralateral recurrence. High MI (P = 0.007) was significantly correlated with poor cancer-specific survival. Multivariate analysis indicated that unmethylated RASSF1A (P = 0.039), lack of bladder recurrence prior to contralateral UTUC (P = 0.009), history of renal transplantation (P < 0.001), and preoperative renal insufficiency (P = 0.002) are independent risk factors for contralateral UTUC recurrence after RNU.

Conclusions

Our data suggest a potential role of DNA methylation in predicting contralateral UTUC recurrence after RNU. Such information could help identify patients at high risk of new contralateral UTUC recurrence after RNU who need close surveillance during follow up.

Global gene expression profiling identifies ALDH2, CCNE1 and SMAD3 as potential prognostic markers in upper tract urothelial carcinoma

Background

Current knowledge about the molecular properties and prognostic markers of upper tract urothelial carcinoma (UTUC) is sparse and often based on bladder urothelial carcinoma (UC), which is thought to share common risk factors with UTUC. However, studies have suggested that differences exist regarding tumor behavior and molecular biology of these cancers, comprehensive investigations are needed to guide the clinical management of UTUC. In recent years, massively parallel sequencing has allowed insights into the biology of many cancers, and molecular prognostic markers based on this approach are rapidly emerging. The goal of this study was to characterize the gene expression patterns of UTUC using massively parallel sequencing, and identify potential molecular markers for prognosis in patients with UTUC.

Methods

We compared the genome-wide mRNA expression profile of cancer and matched normal tissues from 10 patients with UTUC to identify significantly deregulated genes. We also examined the protein levels of prognostic marker candidates in 103 patients with UTUC, and tested the association of these markers with overall survival using Kaplan-Meier model and Cox regression.

Results

Functional enrichment of significantly deregulated genes revealed that expression patterns of UTUC were characterized by disorders of cell proliferation and metabolism. And we also compared the expression profile of UTUC with that of bladder UC. Our results highlighted both shared (e.g. disorders of cell cycling and growth signal transduction) and tumor-specific (e.g. abnormal metabolism in UTUC and disruptions of adhesion pathways in bladder UC) features of these two cancers. Importantly, we identified that low protein expression of ALDH2 while high CCNE1 and SMAD3 were significantly associated with increased depth (*P <0.05) and lower overall survival (***P <0.0001) in an independent set of 103 patients. Multivariate Cox regression revealed that all these three genes were independent prognostic indicators in patients with UTUC (***P <0.001).

Conclusions

In conclusion, our study characterized the comprehensive expression profile of UTUC and highlighted both commons and differences in expression patterns between UTUC and bladder UC. And we, for the first time, revealed that ALDH2, CCNE1 and SMAD3 are associated with prognosis in patients with UTUC.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-836) contains supplementary material, which is available to authorized users.

[Carcinogenic pathways and natural history of upper tract urothelial carcinomas: state-of-the-art review for the yearly scientific report of the French National Association of Urology]

OBJECTIVE

To describe natural history and carcinogenesis of upper tract urothelial carcinoma (UTUC).

METHODS

A systematic review of the scientific literature was performed in the Medline database (Pubmed) using different associations of the following keywords: upper tract urothelial carcinoma; clonality; carcinogenesis; mutation; chromosomal instability; Lynch syndrome; genetic polymorphism.

RESULTS

Local development of UTUC is characterized by a highly prevalent multifocality that might be explained by the overlap of "field change" and "intraluminal seeding and implantation" theories. UTUC and bladder tumors share common carcinogenesis mechanisms such as mutations of FGFR3 and TP53 defining two distinct pathways of pathogenesis. Epigenetic alterations corresponding to the hypermethylation of different promoters regulating genes expression and chromosomal instability such as chromosome 9 deletions are also involved in UTUC carcinogenesis. Furthermore, specific genetic risk factors fro UTUC including Lynch syndrome and different polymorphisms might explain an individual susceptibility for developing these tumors.

CONCLUSIONS

Significant advances have been done in the field of basic research in UTUCs in recent years and have been of particular interest to provide better descriptions of their natural history. Despite these important findings however, some carcinogenic mechanisms remains not elucidated and unknown in the field of UTUC so far.

Toll-like receptor 6 and connective tissue growth factor are significantly upregulated in mitomycin-C-treated urothelial carcinoma cells under hydrostatic pressure stimulation

BACKGROUND

Urothelial carcinoma (UC) is the most common histologic subtype of bladder cancer. The administration of mitomycin C (MMC) into the bladder after transurethral resection of the bladder tumor (TURBT) is a common treatment strategy for preventing recurrence after surgery. We previously applied hydrostatic pressure combined with MMC in UC cells and found that hydrostatic pressure synergistically enhanced MMC-induced UC cell apoptosis through the Fas/FasL pathways. To understand the alteration of gene expressions in UC cells caused by hydrostatic pressure and MMC, oligonucleotide microarray was used to explore all the differentially expressed genes.

RESULTS

After bioinformatics analysis and gene annotation, Toll-like receptor 6 (TLR6) and connective tissue growth factor (CTGF) showed significant upregulation among altered genes, and their gene and protein expressions with each treatment of UC cells were validated by quantitative real-time PCR and immunoblotting.

CONCLUSION

Under treatment with MMC and hydrostatic pressure, UC cells showed increasing apoptosis using extrinsic pathways through upregulation of TLR6 and CTGF.

Highlights from the first symposium on upper tract urothelial carcinoma

OBJECTIVES

Upper tract urothelial carcinoma (UTUC) is a rare disease in Western countries and garners little focused attention in urologic and oncologic circles. We report highlights from the first symposium on UTUC.

METHODS

All participants were asked to provide a summary of their presentation to be included as part of these proceedings. Submitted summaries were synthesized into this document. All contributors reviewed and provided input on the final draft.

RESULTS

Five highlights are included in this report, including landmark research that not only reveals the likely cause of Balkan endemic nephropathy and associated UTUC but also links it directly to UTUC in Taiwan. Because of the ubiquitous use of Aristolochia plants in these herbal remedies, a public health problem of considerable magnitude is anticipated in Asian countries. Gene expression signatures reveal some differential expression in bladder carcinoma, such as CLCA2 and GABRE. Few urinary markers have proven utility for the diagnosis and follow-up of UTUC, and no tissue or blood-based markers are currently undergoing clinical application. Novel endoscopic therapies provide some hope of improving tissue sampling, diagnosis, and kidney-sparing therapeutics, but the greatest potential lies in improving clinical (preoperative) risk stratification, which is critically limited in this disease. Biomarkers, currently untested, hold promise in identifying patients most likely to benefit from perioperative chemotherapy and at high risk from cisplatin-induced nephrotoxicity.

CONCLUSIONS

Despite its rarity in the West, UTUC is reaching potentially epidemic proportions in the East because of exposure to carcinogenic herbal remedies. Critical trials are needed to improve our understanding and treatment of UTUC. Because of the broad range of comorbid conditions in patients suffering from this disease, it is the consensus of the participants that future clinical trials should be practical in design and applicable to a broad range of patients, diverging from the current dogma of narrow patient selection criteria in clinical trials. Practical designs would maximize accrual for a still uncommon disease, and their findings would be applicable to a larger proportion of patients than current narrowly selected designs.

Gene profiling suggests a common evolution of bladder cancer subtypes

Background

Bladder cancer exists as several distinct subtypes, including urothelial carcinoma (UCa), squamous cell carcinoma (SCCa), adenocarcinoma and small cell carcinoma. These entities, despite showing distinct morphology and clinical behavior, arise from the urothelial lining and are often accompanied by similar precursor/in situ findings. The relationship between these subtypes has not been explored in detail.

Methods

We compared gene expression analysis of the two most common subtypes of bladder cancer, UCa (n = 10) and SCCa (n = 9), with an additional comparison to normal urothelium from non-cancer patients (n = 8) using Affymetrix GeneChip Human genome arrays (Affymetrix, Santa Clara, CA). The results were stratified by supervised and unsupervised clustering analysis, as well as by overall fold change in gene expression.

Results

When compared to normal urothelium, UCa showed differential expression of 155 genes using a 5-fold cut-off. Examples of differentially regulated genes included topoisomerases, cancer-related transcription factors and cell cycle mediators. A second comparison of normal urothelium to SCCa showed differential expression of 503 genes, many of which were related to squamous-specific morphology (desmosomal complex, intermediate filaments present within squamous epithelium, squamous cornifying proteins, and molecules upregulated in squamous carcinomas from other anatomic sites). When compared, 137 genes were commonly dysregulated in both UCa and SCCa as compared to normal urothelium. All dysregulated genes in UCa were shared in common with SCCa, with the exception of only 18 genes. Supervised clustering analysis yielded correct classification of lesions in 26/27 (96%) of cases and unsupervised clustering analysis yielded correct classification in 25/27 (92.6%) of cases.

Conclusions

The results from this analysis suggest that bladder SCCa shares a significant number of gene expression changes with conventional UCa, but also demonstrates an additional set of alterations that is unique to this entity that defines the squamous phenotype. The similarity in deregulated gene products suggests that SCCa may be a much more closely related entity at the molecular level to conventional UCa than previously hypothesized.

Accurate detection of upper tract urothelial carcinoma in tissue and urine by means of quantitative GDF15, TMEFF2 and VIM promoter methylation

AIM OF THE STUDY

Upper tract urothelial carcinoma (UTUC) accounts for 5-10% of all urothelial tumours. It is mostly diagnosed at advanced stages, entailing a worse prognosis, owing to the lack of early and specific symptoms as well as of effective diagnostic tools. We previously identified a panel of epigenetic biomarkers (GDF15, TMEFF2 and VIM promoter methylation) that accurately identifies bladder cancer in urine. Herein, we assessed the performance of the same panel for UTUC detection and prognosis, in tissue and urine.

MATERIAL AND METHODS

Methylation levels of reference and target genes were determined using real-time quantitative methylation-specific polymerase chain reaction (MSP) in bisulphite-modified DNA of 57 UTUC tissues, 36 normal upper tract urothelium (NUTUs), 22 urines from UTUC suspects and 20 urines from controls. Receiver operator characteristics (ROC)-curve analysis was performed to determine the performance of the biomarker panel and survival analyses were conducted to evaluate their prognostic value.

RESULTS

Methylation levels of GDF15, TMEFF2 and VIM were significantly higher in UTUC compared to NUTUs (P=0.022; P<0.001; P<0.001, respectively). The panel accurately identified UTUC with 100% and 91% sensitivity, corresponding to an area under the curve of 1.000 and 0.923 in tissue and urines, respectively, with 100% specificity. Low VIM promoter methylation levels independently predicted poor disease-specific survival.

CONCLUSIONS

GDF15, TMEFF2 and VIM promoter methylation allows for accurate identification of UTUC, in tissue and urine and VIM methylation provides relevant prognostic information, especially in high-stage disease. This assay may improve the clinical management of UTUC patients.

IGFBP-5 overexpression as a poor prognostic factor in patients with urothelial carcinomas of upper urinary tracts and urinary bladder

BACKGROUND

Urothelial carcinoma (UC) is prevalent worldwide. Dysregulation of cell growth is a critical event of tumorigenesis and has not been assessed systemically in UC. We thus assessed the published transcriptome of urinary bladder urothelial carcinoma (UBUC) and identified insulin-like growth factor-binding protein-5 (IGFBP-5) as the most significantly upregulated gene associated with the regulation of cell growth. Moreover, validated by using public domain data set, IGFBP-5 expression also significantly predicted worse outcome. IGFBP-5 is one of the binding proteins that regulate insulin-like growth factors (IGFs) and its significance has not been comprehensively evaluated in UCs.

METHODS

Using immunohistochemistry, we evaluated the IGFBP-5 expression status and its associations with clinicopathological features and survival in 340 cases of upper urinary tract urothelial carcinoma (UTUC) and 295 cases of UBUC. Western blot analysis was used to evaluate IGFBP-5 protein expression in human urothelial cell (HUC) lines.

RESULTS

IGFBP-5 overexpression was significantly associated with advanced pT stage (p<0.001), high histological grade (UTUC, p<0.001; UBUC, p=0.035), lymph node metastasis (UTUC, p=0.006; UBUC, p=0.004), vascular invasion (UTUC, p<0.001; UBUC, p=0.003), perineural invasion (UTUC, p=0.034; UBUC, p=0.021) and frequent mitosis (UTUC, p<0.001; UBUC, p=0.023). IGFBP-5 overexpression also independently predicted poor disease-specific survival and metastasis-free survival in both groups of patients. Western blot analysis showed IGFBP-5 protein as overexpressed in human urothelial cancer cell lines and not in normal urothelial cancer cells.

CONCLUSIONS

IGFBP-5 plays an important role in tumour progression in UC. Its overexpression is associated with advanced tumour stage and conferred poorer clinical outcome.

Distinct patterns and behaviour of urothelial carcinoma with respect to anatomical location: how molecular biomarkers can augment clinico-pathological predictors in upper urinary tract tumours

PURPOSE

Upper urinary tract urothelial carcinoma (UTUC) shares many similarities with bladder-UC, but there is strong evidence on a clinical, aetiological, epidemiological and genetic level that key differences exist. In this review, we aim to highlight how UTUC differs from bladder-UC and report on the utility of molecular markers in the diagnosis and management of UTUC.

MATERIALS AND METHODS

A systematic literature search was conducted using the Medline and Embase databases and specific keyword combinations: 'urothelial carcinoma', 'bladder cancer', 'transitional cell carcinoma', 'upper tract', 'upper urinary tract', 'genetics', 'prognosis' and 'biomarkers'.

RESULTS

UTUC has specific acquired (e.g. Balkans nephropathy, phenacetin abuse) and genetic hereditary non-polyposis colorectal cancer risk factors compared with bladder-UC. In general, the molecular biology of UC is broadly similar, irrespective of location in the urinary tract. However, there are distinct genetic (microsatellite instability) and epigenetic (hypermethylation) differences between some UTUC and bladder-UC. Clinical-pathological variables (e.g. hydronephrosis, tumour architecture, tumour location, stage and grade) have independent predictive power in UTUC, but tissue and urinary biomarkers can improve the clinical prediction of recurrence, invasion and survival in UTUC, though the evidence level is weak.

CONCLUSIONS

UTUC shares many similarities with bladder-UC, but there is strong evidence that they should be considered as distinct urothelial entities. Prospective multi-institutional studies investigating molecular markers are urgently needed to augment clinic-pathological predictors in UTUC.

FXYD3: A Promising Biomarker for Urothelial Carcinoma

Objective:

Urothelial carcinoma (UC) of the kidney is a relatively rare but aggressive form of kidney cancer. Differential diagnosis of renal UC from renal cell carcinoma (RCC) can be difficult, but is critical for correct patient management. We aimed to use global gene expression profiling to identify genes specifically expressed in urothelial carcinoma (UC) of the kidney, with purpose of finding new biomarkers for differential diagnosis of UC of both upper and lower tract from normal tissues.

Materials and methods:

Microarray gene expression profiling was performed on a variety of human kidney tumor samples, including clear cell, papillary, chromophobe, oncocytoma, renal UC and normal kidney controls. Differentially expressed mRNAs in various kidney tumor subtypes were thus identified. Protein expression in human UC tumor samples from both upper and lower urinary tract was evaluated by immunohistochemistry.

Results:

FXYD3 (MAT-8) mRNA was specifically expressed in UC of the kidney and not in normal kidney tissue or in any RCC tumor subtypes. FXYD3 mRNA levels displayed equal or better prediction rate for the detection of renal UC than the mRNA levels of selected known UC markers as p63, vimentin, S100P, KRT20 and KRT7. Finally, immunohistochemical staining of clinical UC samples showed that FXYD3 protein is overexpressed in majority of UC of the upper genitourinary tract (encompassing the kidney, ∼90%) and in majority of high grade bladder UC (∼84%, it’s <40% in low grade tumors, P < 0.001) compared to normal kidney and bladder tissues.

Conclusion:

FXYD3 may be a promising novel biomarker for the differential diagnosis of renal UC and a promising prognosis marker of UC from bladder. Because it was identified genome-widely, FXYD3 may have important biological ramifications for the genetic study of UC.