Molecular pathogenesis of bladder cancer. Int J Clin Oncol. 2008;13:287-297. [PMID: 18704628 DOI: 10.1007/s10147-008-0812-0]

Genetic insights into bladder cancer: the impact of SIRT1 gene polymorphism

Bladder cancer (BC) has shown a significant global health concern with distinct pathological, genetic, and epigenetic characteristics. Its prevalence is influenced by various risk factors, including age, gender, and genetic predisposition. This study investigates the association between BC and the Sirtuin 1 (SIRT1) gene polymorphism rs369274325 in the Turkish population. Genomic DNA was isolated from peripheral blood samples and genotyping of rs369274325 polymorphism in SIRT 1 was investigated in 200 individuals (in 100 Turkish bladder cancer patients and 100 healthy individuals as the control group.) by real-time PCR. Demographic information, smoking and alcohol consumption status was analyzed by statistical analysis. Statistical analysis was performed by Pearson's Chi-square test. Smoking and alcohol consumption were significantly higher in BC patients compared to controls (p < 0.00018 and p < 0.0001, respectively). The genotypic distribution of SIRT1 rs369274325 did not show a significant difference between BC patients and controls (p = 0.5550). BC, influenced by genetic and environmental factors, has been linked to various gene mutations. SIRT1, involved in diverse physiological processes, is proposed to play a role in BC. However, our study did not find a significant association between SIRT1 rs369274325 polymorphism and BC in the Turkish population.

Animal Models in Bladder Cancer

BACKGROUND

Bladder cancer (urothelial cancer of the bladder) is the most common malignancy affecting the urinary system with an increasing incidence and mortality. Mouse models of bladder cancer should possess a high value of reproducibility, predictability, and translatability to allow mechanistic, chemo-preventive, and therapeutic studies that can be furthered into human clinical trials.

OBJECTIVES

To provide an overview and resources on the origin, molecular and pathological characteristics of commonly used animal models in bladder cancer.

METHODS

A PubMed and Web of Science search was performed for relevant articles published between 1980 and 2021 using words such as: "bladder" and/or "urothelial carcinoma" and animal models. Animal models of bladder cancer can be categorized as autochthonous (spontaneous) and non-autochthonous (transplantable). The first are either chemically induced models or genetically engineered models. The transplantable models can be further subclassified as syngeneic (murine bladder cancer cells implanted into immunocompetent or transgenic mice) and xenografts (human bladder cancer cells implanted into immune-deficient mice). These models can be further divided-based on the site of the tumor-as orthotopic (tumor growth occurs within the bladder) and heterotopic (tumor growth occurs outside of the bladder).

CircNT5E promotes the proliferation and migration of bladder cancer via sponging miR-502-5p

Accumulating evidence suggest that circRNA RNAs (circRNAs) play important roles in tumor formation and development. circNT5E has been shown to be an oncogenic gene in several types of cancer, and the high expression of circNT5E lead to tumorigenesis and cancer progression. However, the precise role of circNT5E in bladder cancer (Bca) has not been characterized. In this study, we observed that circNT5E expression was augmented in Bca tissues compared with that in adjacent normal tissues, and its expression level was positively associated with larger tumor size and lower survival rate. Further experiments showed that suppression of circNT5E restrained the growth and metastasis of Bca cells in vitro. circNT5E was mainly distributed in the cytoplasm and it captured miR-502-5p to increase HOXC8 mRNA and protein expression. Moreover, decreased miR-502-5p obviously reversed the circNT5E silencing-mediated inhibition of Bca cell growth and migration. Thus, this study suggested that circNT5E may act as a pro-oncogene in the development and progression of Bca and it may become a useful tumor biomarker and promising therapeutic target for Bca treatment.

Effect of the Paris system for reporting urinary cytology with histologic follow-up

BACKGROUND

The Paris system (TPS) for Reporting Urinary Cytology provides a standardized reporting system whose main focus is the diagnosis of high-grade urothelial carcinoma (HGUC). We conducted a study to see the impact of The Paris System on our cytologic diagnoses with associated histology.

MATERIALS AND METHODS

We reviewed our pathology database regarding urinary specimens in the year before implementation of The Paris System and the year after. We gathered the data regarding cytologic diagnosis and concurrent/subsequent histology.

RESULTS

Over a 1-year period from 2016-2017, 486 urine cytology specimens were identified before implementation of The Paris System and diagnosed as follows: 83% benign/negative, 10% atypical, 2% suspicious, 5% HGUC, 0.2% low grade urothelial neoplasm (LGUN), and 0.2% unsatisfactory. Over a next 1-year period from 2017 to 2018, 602 specimens used TPS and diagnosed as follows: 85% negative for HGUC, 6% atypical, 3% suspicious, 4% HGUC, 0.17% LGUN, and 2% unsatisfactory. Although, not listed as a standardized category in The Paris System, our institution used "Negative for high-grade, cannot rule out low-grade urothelial neoplasm (NHL)" as a subcategory of Negative for HGUC. 4% of the cases fell into this category. Focusing on the Atypical category before TPS, histology was available in 15/49 (31%) cases. Of these, 40% had HGUC. Regarding the Atypical category after TPS, histology was available in 21/36 (58%) cases. Of these, 52% were HGUC. For the NHL category, concurrent histology was available in 13/26 (50%) cases. Of these, 67% were low grade urothelial neoplasms.

CONCLUSION

Our study showed that TPS lowered the rate of Atypical from 10% to 6%. After the implementation of TPS, Atypical corresponded to a higher rate of high-grade urothelial carcinoma. Also, the NHL subcategory had a high positive predictive value for diagnosing low grade urothelial neoplasms.

Analysis of FGFR3 and HRAS genes in patients with bladder cancer

Background: Bladder cancer is the most frequent malignancy that affects the urinary tract. Studies have shown different types of FGFR3 and HRAS genes mutations in human bladder cancer, with a comprehensive range of mutation number in various populations. This study aimed to determine the specific point mutations of these 2 genes among Iranian patients with bladder cancer. Methods: In this study, 100 specimens of patients with transitional cell carcinoma were analyzed. All samples were examined for FGFR3 and HRAS mutations using PCR and direct DNA sequencing methods. Results: A total of 9 pathogenic mutations and 9 polymorphisms were found in 2 exons (7 and 15) of the FGFR3 genes in patients with bladder cancer (S249Y, I633I, L645L, D646E, Y647*, D628V, P250T, Q263H, Y305H). However, no mutation was found in exon 10 of FGFR3 and exon 1 of HRAS genes. Conclusion: In this study, 5 mutations were found in FGFR3 gene that have not been detected previously. There was no mutation in exon 10 of FGFR3 and exon1 of HRAS. The results of this study confirmed the association of ethnic-genetic factors in the occurrence of bladder cancer, so that these variables may not be present in all ethnic groups.

Targeting antisense mitochondrial noncoding RNAs induces bladder cancer cell death and inhibition of tumor growth through reduction of survival and invasion factors

Knockdown of the antisense noncoding mitochondrial RNAs (ASncmtRNAs) induces apoptotic death of several human tumor cell lines, but not normal cells, supporting a selective therapy against different types of cancer. In this work, we evaluated the effects of knockdown of ASncmtRNAs on bladder cancer (BCa). We transfected the BCa cell lines UMUC-3, RT4 and T24 with the specific antisense oligonucleotide Andes-1537S, targeted to the human ASncmtRNAs. Knockdown induced a strong inhibition of cell proliferation and increase in cell death in all three cell lines. As observed in UMUC-3 cells, the treatment triggered apoptosis, evidenced by loss of mitochondrial membrane potential and Annexin V staining, along with activation of procaspase-3 and downregulation of the anti-apoptotic factors survivin and Bcl-xL. Treatment also inhibited cell invasion and spheroid formation together with inhibition of N-cadherin and MMP 11. In vivo treatment of subcutaneous xenograft UMUC-3 tumors in NOD/SCID mice with Andes-1537S induced inhibition of tumor growth as compared to saline control. Similarly, treatment of a high-grade bladder cancer PDX with Andes-1537S resulted in a strong inhibition of tumor growth. Our results suggest that ASncmtRNAs could be potent targets for bladder cancer as adjuvant therapy.

Discoidin Domain Receptor 1 functionally interacts with the IGF-I system in bladder cancer

Bladder cancer is one of the most common and aggressive cancers and, regardless of the treatment, often recurs and metastasizes. Thus, a better understanding of the mechanisms regulating urothelial tumorigenesis is critical for the design and implementation of rational therapeutic strategies. We previously discovered that the IGF-IR axis is critical for bladder cancer cell motility and invasion, suggesting a possible role in bladder cancer progression. However, IGF-IR depletion in metastatic bladder cancer cells only partially inhibited anchorage-independent growth. Significantly, metastatic bladder cancer cells have decreased IGF-IR levels but overexpressed the insulin receptor isoform A (IR-A), suggesting that the latter may play a more prevalent role than the IGF-IR in bladder tumor progression. The collagen receptor DDR1 cross-talks with both the IGF-IR and IR in breast cancer, and previous data suggest a role of DDR1 in bladder cancer. Here, we show that DDR1 is expressed in invasive and metastatic, but not in papillary, non-invasive bladder cancer cells. DDR1 is phosphorylated upon stimulation with IGF-I, IGF-II, and insulin, co-precipitates with the IGF-IR, and the IR-A and transient DDR1 depletion severely inhibits IGF-I-induced motility. We further demonstrate that DDR1 interacts with Pyk2 and non-muscle myosin IIA in ligands-dependent fashion, suggesting that it may link the IGF-IR and IR-A to the regulation of F-actin cytoskeleton dynamics. Similarly to the IGF-IR, DDR1 is upregulated in bladder cancer tissues compared to healthy tissue controls. Thus, our findings provide the first characterization of the molecular cross-talk between DDR1 and the IGF-I system and could lead to the identification of novel targets for therapeutic intervention in bladder cancer. Moreover, the expression profiles of IGF-IR, IR-A, DDR1, and downstream effectors could serve as a novel biomarker signature with diagnostic and prognostic significance.

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We discovered that the collagen receptor DDR1 cross-talks with insulin growth factor I (IGF-I) signaling in bladder cancer

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DDR1 co-precipitates with the IGF-IR and the insulin receptor (IR), and is phosphorylated upon stimulation with IGF ligands

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This collagen receptor modulates IGF-I-evoked motility and anchorage-independent growth

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DDR1 complexes with Pyk2, myosin IIA, IGF-IR and/or IR and regulates actin dynamics

Circular RNA CEP128 promotes bladder cancer progression by regulating Mir-145-5p/Myd88 via MAPK signaling pathway

The present experiment was designed for exploring the regulatory mechanism of circ-CEP128/miR-145-5p/MYD88 axis in bladder cancer. MiRNAs and circRNAs expression data were derived from Gene Expression Omnibus database with bladder tumor tissues and paracarcinoma tissue samples. Differentially expressed genes in tumor were analyzed via R software. Interaction network of differently expressed miRNAs and differently expressed mRNA was established by means of Cytoscape software. CircCEP128 and miR-145-5p expression levels were determined using qRT-PCR. The expression of MAPK signaling-related proteins MYD88, p38, ERK and JNK was examined by western blot. The relationship between circCEP128 and miR-145-5p was validated using RNA immunoprecipitation. The level of cell propagation and migration was determined by CCK8 and wound healing assay, 5-bromo-2'-deoxyuridine assay and migration assay. Cell apoptosis rate and cell cycle were detected via flow cytometry. Tumor xenograft assay was implemented to investigate the function of circCEP128 in vivo. CircCEP128 and MYD88 were overexpressed in bladder cancer based on microarray analysis and miR-145-5p was a potential targeting factor in bladder cancer. CircCEP128 targeted miR-145-5p and miR-145-5p targeted MYD88. Expression of miR-145-5p was decreased in cancer samples. Knockdown of circCEP128 induced the inhibition of cell viability and mobility and cell cycle arrest. Overexpression of miR-145-5p or knockdown of circCEP128 promoted MAKP signaling pathway and related proteins expression. In addition, knockdown of circCEP128 suppressed the growth of bladder cancer tumor tissues in vivo. Overexpression of circCEP128 promoted bladder cancer progression through modulating miR-145-5p and MYD88 via MAKP signaling pathway.

miR-3622a promotes proliferation and invasion of bladder cancer cells by downregulating LASS2

As a tumor metastasis suppressor gene, LASS2 has been found to be negatively associated with the stage of bladder cancer and overall survival of patients. However, the mechanisms regulating LASS2 in bladder cancer remain poorly understood. Here, we aim to identify a miRNA that targets LASS2 from bladder cancer-associated miRNAs and to reveal its potential functions in bladder cancer cells. Through miRNA microarray and bioinformatics analyses, we identified miR-3622a as a negative regulator of LASS2. The expression levels of miR-3622a in bladder cancer tissues were negatively correlated with the overall survival of patients. Overexpression of miR-3622a significantly increased the proliferation and invasion abilities of bladder cancer cells. In conclusion, our results indicate that miR-3622a promotes the proliferation and invasion of bladder cancer cells by downregulating LASS2.

The functions of microRNA-124 on bladder cancer

Background: To detect the expression of miR-124 in bladder cancer (BC) cell lines and tissue specimens and to analyze its association with the growth of the BC cells.

Methods: Quantitative real-time polymerase chain reaction (qPCR) was applied to examine the expression of miR-124 in BC cell lines and tissues. The function of miR-124 in modulating cell proliferation was assessed in BC cells with miRNA-124 overexpression; the cell viability was identified by Cell Count Kit-8; flow cytometry was employed to detect the cell cycle; the expressions of E2F3, cyclin-dependent kinase 4 (CDK4), Ki-67 and vascular endothelial growth factor (VEGF) were tested by qPCR and Western blot; angiogenesis experiment was performed to analysis changes in angiogenesis rate; and bioinformatics prediction and dual luciferase reporter system were employed to identify the target of miR-124.

Results: Survival curve data showed that the expression of MicroRNA-124 was positively correlated with survival. MicroRNA-124 expression was significantly decreased in BC cell lines and tissues. Bioinformatics prediction and dual luciferase reporter system verified CDK4 as a direct target of miR-124, which regulated the proliferation of BC cells by directly inhibiting CDK4. BC cells over-expressing miR-124 showed significantly inhibited cell viability, decreased angiogenesis rate, prevented cell proliferation and diminished the expression of E2F3, CDK4, Ki-67 and VEGF. All of these changes were reversed by over-expressing CDK4.

Conclusion: MicroRNA-124 suppressed the proliferation of CRC cells by directly targeting CDK4, which provides a target for improving the therapeutic effect of BC.

Increased AURKA promotes cell proliferation and predicts poor prognosis in bladder cancer

Background

Bladder cancer (BC) is the most common cancer of the urinary bladder and upper tract, in which the clinical management is limited. AURKA (aurora kinase A) has been identified as an oncogene in cancer development; however, its potential role and underlying mechanisms in the progression of BC remain unknown.

Results

In this study, we evaluated Aurora kinase A (AURKA) expression in patient samples by performing gene expression profiling, and found that AURKA expression levels were significantly higher in BC tissues than in normal tissues. Increased AURKA in BC was strongly associated with stage and grade. Moreover, BC patients with elevated AURKA achieved poor overall survival rates. The experiments in vitro comprehensively validated the critical role of AURKA in promoting BC cell proliferation using the methods of gene overexpression and gene silencing. Furthermore, we proved that AURKA inhibitor MLN8237 arrested BC cell growth and induced apoptosis.

Conclusions

These findings implicate AURKA acting as an effective biomarker for BC detection and prognosis, as well as therapeutic target.

Expression pattern of p53-binding protein 1 as a new molecular indicator of genomic instability in bladder urothelial carcinoma

Copy number alterations and loss of heterozygosity are associated with increasing tumor grade and bladder cancer stage. Our previous study suggested that co-expression of Ki-67 and p53-binding protein 1 (53BP1) could provide an indicator of an abnormal DNA damage response (DDR) pathway. The present study investigated 53BP1 expression as a novel molecular marker in urothelial carcinoma (UC) using bladder tissues with in total of 40 cases including a normal urothelium, urothelial papilloma, low-grade UC, or high-grade UC. Double-label immunofluorescence was used to analyze 53BP1 and Ki-67 expression. This was compared with the level of chromosomal instability and with the expression of other DDR molecules catalytic subunit. This study identified clear differences in the 53BP1 expression patterns in urothelial carcinogenesis, and their close association with genomic instability. 53BP1 abnormal immunoreactivity, particularly with co-localization of Ki-67, was restricted to malignant tissues. Our analyses indicated that a cut-off of >4% of nuclei with 53BP1 abnormal expression plus Ki-67 immunoreactivity distinguished high-grade UC from low-grade UC with 80.0% sensitivity and 100% specificity. We therefore propose that double immunofluorescent analysis of 53BP1 and Ki-67 expression could provide a useful tool to estimate the chromosomal instability and malignant potential of urothelial tumors.

CREB1, a direct target of miR-122, promotes cell proliferation and invasion in bladder cancer

Bladder cancer (BC) is a prevalent cancer, which arises from the epithelial lining of the urinary bladder. CAMP-response element binding protein (CREB1) acts as a transcription factor, which regulates cell transcription through phosphorylation and dephosphorylation. The purpose of this study was to explore how miR-122 worked in BC on cell proliferation and invasion. RT-qPCR was applied to evaluate the mRNA levels of CREB1 and miR-122 in BC. CCK-8 and Transwell assays were employed to determine the migratory and invasive abilities. Dual luciferase reporter assay was applied to verify miR-122 targeting CREB1 in BC. CREB1 was upregulated in bladder tissues and T24, UM-UC-3 and J82 cells, while miR-122 upregulated and had negative correlation with CREB1. Moreover, knockdown of CREB1 inhibited cell proliferative and invasive capacities. In addition, CREB1 was directly targeted by miR-122 in BC and regulated its expression. We discovered that CREB1 could reverse partially the function of miR-122 on cell proliferation and invasion. CREB1 was mediated by miR-122, and regulated cell proliferation and invasiveness. The newly identified miR-122/CREB1 axis provides novel insight into the pathogenesis of BC.

Paris Interobserver Reproducibility Study (PIRST)

OBJECTIVES

In concert with the 2015 publication of The Paris System for Urinary Cytopathology (TPS), a Web-based interobserver study, co-sponsored by the American Society of Cytopathology (ASC) and International Academy of Cytology (IAC), was performed to determine diagnostic agreement among volunteer participants and with the TPS author consensus.

MATERIAL AND METHODS

Participants at various levels of training and certification were recruited through national and international cytopathology professional societies. Although the survey was open to all comers, potential participants were screened by two basic cytopathology questions. Information was collected on the level of training, practice patterns, and experience. Study participants evaluated 85 images (previously unpublished) chosen from the TPS atlas. These images spanned all diagnostic categories.

RESULTS

Of the 1993 attempts to access the survey, 1313 participants correctly answered the qualifying questions and were included in the survey. Respondents were concentrated in the United States, although many participants came from other countries. The majority of respondents were board-certified in anatomic pathology with cytopathology certification. A smaller number were cytotechnologists. Board-certified cytopathologists and specialist cytotechnologists outperformed other certifications. Practice type (academics versus non-academic), and country (US versus international) were not major factors in concordance. Diagnostic categories with the best agreement were Negative for High-Grade Urothelial Carcinoma (NHGUC; 71%), Low-Grade Urothelial Neoplasm (LGUN; 62%), and High-Grade Urothelial Carcinoma (HGUC; 57%). Indeterminate categories showed low concordance.

CONCLUSIONS

The NHGUC, LGUN, and HGUC were most correlated with diagnostic agreement among observers. This study can serve as a baseline for future comparisons.

MKAD-21 Suppresses the Oncogenic Activity of the miR-21/PPP2R2A/ERK Molecular Network in Bladder Cancer

Bladder cancer represents a disease associated with significant morbidity and mortality. MiR-21 has been found to have oncogenic activity in multiple cancers, including bladder cancer, whereas inhibition of its expression suppresses tumor growth. Here, we examine the molecular network regulated by miR-21 in bladder cancer and evaluate the effects of i.v. and i.p. administration of a novel miR-21 chemical inhibitor in vivo LNA miR-21 reduced the oncogenic potential of bladder cancer cells, whereas the MKAD-21 chemically modified antisense oligo against miR-21 dose-dependently blocked xenograft growth. I.v. administration of LNA miR-21 was more effective in suppressing tumor growth than was i.p. administration. Integration of computational and transcriptomic analyses in a panel of 28 bladder cancer lines revealed a 15-gene signature that correlates with miR-21 levels. Protein Phosphatase 2 Regulatory Subunit Balpha (PPP2R2A) was one of these 15 genes and was experimentally validated as a novel miR-21 direct target gene. Gene network and molecular analyses showed that PPP2R2A is a potent negative regulator of the ERK pathway activation and bladder cancer cell proliferation. Importantly, we show that PPP2R2A acts as a mediator of miR-21-induced oncogenic effects in bladder cancer. Integrative analysis of human bladder cancer tumors and a large panel of human bladder cancer cell lines revealed a novel 15-gene signature that correlates with miR-21 levels. Importantly, we provide evidence that PPP2R2A represents a new miR-21 direct target and regulator of the ERK pathway and bladder cancer cell growth. Furthermore, i.v. administration of the MKAD-21 inhibitor effectively suppressed tumor growth through regulation of the PPP2R2A-ERK network in mice. Mol Cancer Ther; 17(7); 1430-40. ©2018 AACR.

Biological significance of TERT promoter mutation in papillary urothelial neoplasm of low malignant potential

AIMS

Mutations in FGFR3 and the promoter region of the telomerase reverse transcriptase (TERT) gene have been found frequently in urothelial carcinoma of the urinary bladder. However, related data for papillary urothelial neoplasm of low malignant potential (PUNLMP) are limited. In this study, we investigated the mutation status of the TERT promoter, FGFR3 and HRAS in low-grade papillary urothelial neoplasms and evaluated their prognostic significance.

METHODS AND RESULTS

The cases included in this study comprised 21 inverted papillomas, 30 PUNLMPs and 34 low-grade non-invasive papillary urothelial carcinomas (NIPUCs). TERT promoter mutations were observed in 10 (33%) PUNLMPs and 17 (50%) low-grade NIPUCs, but not in any inverted papilloma. FGFR3 mutations were observed more frequently in PUNLMP and low-grade NIPUC than in inverted papillomas (P = 0.009), whereas the opposite trend was noted for HRAS mutations (P < 0.001). Regarding the clinical outcome, TERT promoter mutation was associated with a higher recurrence rate in PUNLMP (P = 0.024) but not in low-grade NIPUC (P = 0.530). Notably, PUNLMP cases with TERT promoter mutations had a similar recurrence rate to that in low-grade NIPUC cases (P = 0.487).

CONCLUSIONS

Our results suggest that the status of the TERT promoter mutation may serve as a biomarker of prognostic stratification in patients with PUNLMP.

SLC14A1: a novel target for human urothelial cancer

Urinary bladder cancer is the second commonly diagnosed genitourinary malignancy. Previously, bio-molecular alterations have been observed within certain locations such as chromosome 9, retinoblastoma gene and fibroblast growth factor receptor-3. Solute carrier family 14 member 1 (SLC14A1) gene encodes the type-B urea transporter (UT-B) which facilitates the passive movement of urea across cell membrane, and has recently been related with human malignancies, especially for bladder cancer. Herein, we discussed the SLC14A1 gene and UT-B protein properties, aiming to elucidate the expression behavior of SLC14A1 in human bladder cancer. Furthermore, by reviewing some well-established theories regarding the carcinogenesis of bladder cancer, including several genome wide association researches, we have bridged the mechanisms of cancer development with the aberrant expression of SLC14A1. In conclusion, the altered expression of SLC14A1 gene in human urothelial cancer may implicate its significance as a novel target for research.

Implementation of the Paris System for Reporting Urinary Cytology results in lower atypical diagnostic rates

INTRODUCTION

The Paris System for Reporting Urinary Cytology (PSRUC) provides a standardized reporting schema for urine cytology with defined criteria for each diagnostic category. We report the impact at our institution of adopting the PSRUC on the frequency and distribution of urine cytology diagnoses, with particular attention to the "atypical" category as it serves as a potential laboratory quality control measure.

MATERIALS AND METHODS

Urine cytology specimen diagnoses were evaluated during 5-month periods prior to and after the introduction of PSRUC. The number of cases in each diagnostic category by either the laboratory as a whole or by individual cytopathologists were analyzed. Following confidential feedback given to individual cytopathologists, a third 5-month period of cytology diagnosis analysis was performed.

RESULTS

The overall laboratory atypical call rate was significantly lower in the post-PSRUC as compared with the pre-PSRUC period (29.5% versus 21.8%; P < 0.0001), with individual cytopathologist atypical call rate lower post-PSRUC (range: 10.2%-37.9%) compared with pre-PSRUC (range: 12.2%-45.0%). The institution of feedback based on these findings did not result in any further statistical change in the atypical call rate (21.8% versus 22.2%).

CONCLUSIONS

Adoption of PSRUC resulted in a significant decrease in the number of atypical diagnoses with little change in the suspicious or malignant categories. Future studies are needed to determine the effect of decreased atypical call rates on the sensitivity/specificity of urine cytopathology, as well as to see if other measures (such as continued cytopathologist feedback or educational modules) can further reduce atypical rates.

Identification of a Novel UT-B Urea Transporter in Human Urothelial Cancer

The urea transporter UT-B is widely expressed and has been studied in erythrocyte, kidney, brain and intestines. Interestingly, UT-B gene has been found more abundant in bladder than any other tissue. Recently, gene analyses demonstrate that SLC14A1 (UT-B) gene mutations are associated with bladder cancer, suggesting that urea transporter UT-B may play an important role in bladder carcinogenesis. In this study, we examined UT-B expression in bladder cancer with human primary bladder cancer tissues and cancer derived cell lines. Human UT-B has two isoforms. We found that normal bladder expresses long form of UT-B2 but was lost in 8 of 24 (33%) or significantly downregulated in 16 of 24 (67%) of primary bladder cancer patients. In contrast, the short form of UT-B1 lacking exon 3 was detected in 20 bladder cancer samples. Surprisingly, a 24-nt in-frame deletion in exon 4 in UT-B1 (UT-B1Δ24) was identified in 11 of 20 (55%) bladder tumors. This deletion caused a functional defect of UT-B1. Immunohistochemistry revealed that UT-B protein levels were significantly decreased in bladder cancers. Western blot analysis showed a weak UT-B band of 40 kDa in some tumors, consistent with UT-B1 gene expression detected by RT-PCR. Interestingly, bladder cancer associate UT-B1Δ24 was barely sialylated, reflecting impaired glycosylation of UT-B1 in bladder tumors. In conclusion, SLC14A1 gene and UT-B protein expression are significantly changed in bladder cancers. The aberrant UT-B expression may promote bladder cancer development or facilitate carcinogenesis induced by other carcinogens.

MicroRNA-379-5p plays a tumor-suppressive role in human bladder cancer growth and metastasis by directly targeting MDM2

Bladder cancer is the second most common urological malignancy in the US and is the most frequently diagnosed urological malignancy in China. An increasing amount of evidence indicates that microRNAs perform extremely important functions in many biological processes related to the formation and progression of cancers, including bladder cancer. Previous studies have reported that microRNA‑379-5p (miR-379-5p) is involved in tumour initiation and development in human cancers. However, the expression pattern, biological functions and the underlying mechanisms of miR-379-5p in bladder cancer remain unknown. The present study demonstrated that the expression levels of miR‑379-5p in bladder cancer tissues and cell lines were lower than the levels in adjacent normal tissues and the human bladder epithelial immortalized SV-HUC-1 cell line. Restoration of the expression of miR-379-5p inhibited bladder cancer cell proliferation, migration and invasion. Mouse double minute 2 (MDM2) was identified as a direct target gene of miR-379-5p. Furthermore, similar to miR-379-5p overexpression in bladder cancer cells, inhibition of MDM2 exerted tumor-suppressive effects. Rescue experiments showed that upregulation of MDM2 reversed the inhibitory effects of miR-379-5p on bladder cancer cell proliferation, migration and invasion. MDM2 was highly expressed and inversely correlated with miR-379-5p expression in bladder cancer tissues. These findings suggest that the miR-379-5p/MDM2 pathway plays an important role in bladder cancer and could serve as a potential candidate for bladder cancer therapeutics.

Prognostic and predictive miRNA biomarkers in bladder, kidney and prostate cancer: Where do we stand in biomarker development?

PURPOSE

Defining reliable biomarkers is still a challenge in patients with urological tumors. Because miRNAs regulate diverse important cellular processes, these noncoding RNAs are putative molecular candidates. This review intends to give a critical overview about the current state of miRNAs as biomarkers in urological cancers with respect to prognostic stratification as well as for individual treatment selection.

METHODS

A comprehensive review of the published literature was conducted focusing at the clinical relevance of miRNAs in tissues and body fluids of prostate, bladder and kidney cancer. Using electronic database, 91 articles, published between 2009 and 2015, were selected and discussed regarding the robustness of miRNAs as valid biomarkers.

RESULTS

A number of miRNAs have been identified with prognostic and predictive relevance in different urologic tumor types. However, the inconsistency of the published results and the lack of multivariate testing in independent cohorts do not allow an introduction into clinical decision making at present.

CONCLUSION

miRNA-based biomarkers are a promising tool for future personalized risk stratification and response prediction in urological cancers.

The Paris System for Reporting Urinary Cytology: The Quest to Develop a Standardized Terminology

The main purpose of urine cytology is to detect high-grade urothelial carcinoma. With this principle in mind, The Paris System (TPS) Working Group, composed of cytopathologists, surgical pathologists, and urologists, has proposed and published a standardized reporting system that includes specific diagnostic categories and cytomorphologic criteria for the reliable diagnosis of high-grade urothelial carcinoma. This paper outlines the essential elements of TPS and the process that led to the formation and rationale of the reporting system. TPS Working Group, organized at the 2013 International Congress of Cytology, conceived a standardized platform on which to base cytologic interpretation of urine samples. The widespread dissemination of this approach to cytologic examination and reporting of urologic samples and the scheme's universal acceptance by pathologists and urologists is critical for its success. For urologists, understanding the diagnostic criteria, their clinical implications, and limitations of TPS is essential if they are to utilize urine cytology and noninvasive ancillary tests in a thoughtful and practical manner. This is the first international/inclusive attempt at standardizing urinary cytology. The success of TPS will depend on the pathology and urology communities working collectively to improve this seminal paradigm shift, and optimize the impact on patient care.

Suppression of progranulin expression inhibits bladder cancer growth and sensitizes cancer cells to cisplatin

We have recently demonstrated a critical role for progranulin in bladder cancer. Progranulin contributes, as an autocrine growth factor, to the transformed phenotype by modulating Akt-and MAPK-driven motility, invasion and anchorage-independent growth. Progranulin also induces F-actin remodeling by interacting with the F-actin binding protein drebrin. In addition, progranulin is overexpressed in invasive bladder cancer compared to normal tissue controls, suggesting that progranulin might play a key role in driving the transition to the invasive phenotype of urothelial cancer. However, it is not established whether targeting progranulin could have therapeutic effects on bladder cancer. In this study, we stably depleted urothelial cancer cells of endogenous progranulin by shRNA approaches and determined that progranulin depletion severely inhibited the ability of tumorigenic urothelial cancer cells to migrate, invade and grow in anchorage-independency. We further demonstrate that progranulin expression is critical for tumor growth in vivo, in both xenograft and orthotopic tumor models. Notably, progranulin levels correlated with response to cisplatin treatment and were upregulated in bladder tumors. Our data indicate that progranulin may constitute a novel target for therapeutic intervention in bladder tumors. In addition, progranulin may serve as a novel biomarker for bladder cancer.

The Paris System for Reporting Urinary Cytology: The Quest to Develop a Standardized Terminology

The main purpose of urine cytology is to detect high-grade urothelial carcinoma (HGUC). With this principle in mind, The Paris System (TPS) Working Group, composed of cytopathologists, surgical pathologists, and urologists, has proposed and published a standardized reporting system that includes specific diagnostic categories and cytomorphologic criteria for the reliable diagnosis of HGUC. This paper outlines the essential elements of TPS and the process that led to the formation and rationale of the reporting system. The Paris System Working Group, organized at the 2013 International Congress of Cytology, conceived a standardized platform on which to base cytologic interpretation of urine samples. The widespread dissemination of this approach to cytologic examination and reporting of urologic samples and the scheme's universal acceptance by pathologists and urologists is critical for its success. For urologists, understanding the diagnostic criteria, their clinical implications, and the limitations of TPS is essential if they are to utilize urine cytology and noninvasive ancillary tests in a thoughtful and practical manner. This is the first international/inclusive attempt at standardizing urinary cytology. The success of TPS will depend on the pathology and urology communities working collectively to improve this seminal paradigm shift, and optimize the impact on patient care.

The Paris System for Reporting Urinary Cytology: the quest to develop a standardized terminology

The main purpose of urine cytology is to detect high-grade urothelial carcinoma (HGUC). With this principle in mind, The Paris System (TPS) Working Group, composed of cytopathologists, surgical pathologists, and urologists, has proposed and published a standardized reporting system that includes specific diagnostic categories and cytomorphologic criteria for the reliable diagnosis of HGUC. This paper outlines the essential elements of TPS and the process that led to the formation and rationale of the reporting system. The Paris System Working Group, organized at the 2013 International Congress of Cytology, conceived a standardized platform on which to base cytologic interpretation of urine samples. The widespread dissemination of this approach to cytologic examination and reporting of urologic samples and the scheme's universal acceptance by pathologists and urologists is critical for its success. For urologists, understanding the diagnostic criteria, their clinical implications, and the limitations of TPS is essential if they are to utilize urine cytology and noninvasive ancillary tests in a thoughtful and practical manner. This is the first international/inclusive attempt at standardizing urinary cytology. The success of TPS will depend on the pathology and urology communities working collectively to improve this seminal paradigm shift, and optimize the impact on patient care.

Quantitative genome-wide methylation analysis of high-grade non-muscle invasive bladder cancer

High-grade non-muscle invasive bladder cancer (HG-NMIBC) is a clinically unpredictable disease with greater risks of recurrence and progression relative to their low-intermediate-grade counterparts. The molecular events, including those affecting the epigenome, that characterize this disease entity in the context of tumor development, recurrence, and progression, are incompletely understood. We therefore interrogated genome-wide DNA methylation using HumanMethylation450 BeadChip arrays in 21 primary HG-NMIBC tumors relative to normal bladder controls. Using strict inclusion-exclusion criteria we identified 1,057 hypermethylated CpGs within gene promoter-associated CpG islands, representing 256 genes. We validated the array data by bisulphite pyrosequencing and examined 25 array-identified candidate genes in an independent cohort of 30 HG-NMIBC and 18 low-intermediate-grade NMIBC. These analyses revealed significantly higher methylation frequencies in high-grade tumors relative to low-intermediate-grade tumors for the ATP5G2, IRX1 and VAX2 genes (P<0.05), and similarly significant increases in mean levels of methylation in high-grade tumors for the ATP5G2, VAX2, INSRR, PRDM14, VSX1, TFAP2b, PRRX1, and HIST1H4F genes (P<0.05). Although inappropriate promoter methylation was not invariantly associated with reduced transcript expression, a significant association was apparent for the ARHGEF4, PON3, STAT5a, and VAX2 gene transcripts (P<0.05). Herein, we present the first genome-wide DNA methylation analysis in a unique HG-NMIBC cohort, showing extensive and discrete methylation changes relative to normal bladder and low-intermediate-grade tumors. The genes we identified hold significant potential as targets for novel therapeutic intervention either alone, or in combination, with more conventional therapeutic options in the treatment of this clinically unpredictable disease.

A novel role for drebrin in regulating progranulin bioactivity in bladder cancer

We recently established a critical role for the growth factor progranulin in bladder cancer insofar as progranulin promotes urothelial cancer cell motility and contributes, as an autocrine growth factor, to the transformed phenotype by modulating invasion and anchorage-independent growth. In addition, progranulin expression is upregulated in invasive bladder cancer tissues compared to normal controls. However, the molecular mechanisms of progranulin action in bladder cancer have not been fully elucidated. In this study, we searched for novel progranulin-interacting proteins using pull-down assays with recombinant progranulin and proteomics. We discovered that drebrin, an F-actin binding protein, bound progranulin in urothelial cancer cells. We characterized drebrin function in urothelial cancer cell lines and showed that drebrin is critical for progranulin-dependent activation of the Akt and MAPK pathways and modulates motility, invasion and anchorage-independent growth. In addition, drebrin regulates tumor formation in vivo and its expression is upregulated in bladder cancer tissues compared to normal tissue controls. Our data are translationally relevant as indicate that drebrin exerts an essential functional role in the regulation of progranulin action and may constitute a novel target for therapeutic intervention in bladder tumors. In addition, drebrin may serve as novel biomarker for bladder cancer.

Mechanisms of Progranulin Action and Regulation in Genitourinary Cancers

The growth factor progranulin has emerged in recent years as a critical regulator of transformation in several cancer models, including breast cancer, glioblastomas, leukemias, and hepatocellular carcinomas. Several laboratories, including ours, have also demonstrated an important role of progranulin in several genitourinary cancers, including ovarian, endometrial, cervical, prostate, and bladder tumors, where progranulin acts as an autocrine growth factor thereby modulating motility and invasion of transformed cells. In this review, we will focus on the mechanisms of action and regulation of progranulin signaling in genitourinary cancers with a special emphasis on prostate and bladder tumors.

Cell adhesion and urothelial bladder cancer: the role of cadherin switching and related phenomena

Cadherins are mediators of cell-cell adhesion in epithelial tissues. E-cadherin is a known tumour suppressor and plays a central role in suppressing the invasive phenotype of cancer cells. However, the abnormal expression of N- and P-cadherin ('cadherin switching', CS) has been shown to promote a more invasive and m̀alignant phenotype of cancer, with P-cadherin possibly acting as a key mediator of invasion and metastasis in bladder cancer. Cadherins are also implicated in numerous signalling events related to embryonic development, tissue morphogenesis and homeostasis. It is these wide ranging effects and the serious implications of CS that make the cadherin cell adhesion molecules and their related pathways strong candidate targets for the inhibition of cancer progression, including bladder cancer. This review focuses on CS in the context of bladder cancer and in particular the switch to P-cadherin expression, and discusses other related molecules and phenomena, including EpCAM and the development of the cancer stem cell phenotype.

The MDM2 SNP309T>G polymorphism increases bladder cancer risk among Caucasians: a meta-analysis

Published studies have evaluated associations between the MDM2 SNP309T>G polymorphism and bladder cancer susceptibility. However, these generated inconsistent results. The aim of the present investigation was to quantify the strength of association between MDM2 SNP309T>G polymorphism and bladder cancer risk by conducting a meta-analysis. We searched PubMed and Embase for related studies that had been published in English before April 1, 2014 and associations were assessed by summarizing the odds ratios (ORs) with the corresponding 95% confidence intervals (CIs). Five case-control studies with a total of 972 cases and 1,012 controls were finally identified to be eligible for the meta-analysis. Overall, the results indicated that there was no significant association between the MDM2 SNP309T>G polymorphism and bladder cancer risk (for the allele model G vs. T: OR=1.08, 95% CI 0.85-1.36, p=0.54; for the co-dominant model GG vs. TT: OR=1.20, 95% CI 0.74-1.93, p=0.46; for the dominant model GG+GT vs. TT: OR=0.98, 95% CI 0.80-1.20, p=0.83; for the recessive model GG vs. GT+TT: OR=1.20, 95% CI 0.83-1.74, p=0.33). However, on subgroup analysis by ethnicity, significant associations were found in Caucasians in three models (for the allele model G vs. T: OR=1.41, 95% CI 1.10-1.81, p=0.006; for the co-dominant model GG vs. TT: OR=2.16, 95% CI 1.28-3.63, p=0.004; for the recessive model GG vs. GT+TT: OR=2.06, 95% CI 1.31-3.22, p=0.002). In summary, the present meta-analysis provides evidence that the genotype for the MDM2 SNP309T>G polymorphism may be associated with genetic susceptibility to bladder cancer among Caucasians.

Bladder Tumor Heterogeneity: The Impact on Clinical Treatment

Bladder cancer relapse and treatment failure in most patients have often been attributed to chemoresistance in tumor cells and metastasis. Emerging evidence indicates that tumor heterogeneity may play an equally important role and extends to virtually all measurable properties of cancer cells. Although the idea of tumor heterogeneity is not new, little attention has been paid to applying it to understand and control bladder cancer progression. With the development of biotechnology, such as Gene sequencing, recent advances in understanding its generation model, original basis, consequent problems, and derived therapies provide great potential for tumor heterogeneity to be considered a new insight in the treatment of bladder cancers.

Molecular biology of bladder cancer

Classic as well as more recent large-scale genomic analyses have uncovered multiple genes and pathways important for bladder cancer development. Genes involved in cell-cycle control, chromatin regulation, and receptor tyrosine and PI3 kinase-mammalian target of rapamycin signaling pathways are commonly mutated in muscle-invasive bladder cancer. Expression-based analyses have identified distinct types of bladder cancer that are similar to subsets of breast cancer, and have prognostic and therapeutic significance. These observations are leading to novel therapeutic approaches in bladder cancer, providing optimism for therapeutic progress.

Expression of survivin in squamous cell carcinoma and transitional cell carcinoma of the urinary bladder: a comparative immunohistochemical study

Purpose

To compare the expression of survivin and its association with clinicopathological criteria in major types of urinary bladder carcinoma, specifically, transitional cell carcinoma with and without squamous differentiation and squamous cell carcinoma.

Materials and Methods

Immunohistochemical staining for survivin and Ki67 was performed on paraffin-embedded sections of 104 carcinomas: 52 transitional cell carcinoma, 20 transitional cell carcinoma with squamous differentiation, and 32 squamous cell carcinoma. Expression of survivin in >10% of tumor cells was described as altered survivin status. Ki67 staining in >20% of tumor cells was described as a high proliferation index.

Results

Altered survivin expression was detected in 60/104 specimens (58%) and was significantly more frequent in transitional cell carcinoma (78%) than in squamous cell carcinoma (38%) or transitional cell carcinoma with squamous differentiation (40%) (p<0.0001). In transitional cell carcinoma but not in squamous cell carcinoma, altered survivin status was associated with higher tumor grade, higher proliferation index, and recurrence. In the whole specimens, altered survivin expression was significantly associated with advanced stage (p<0.001), recurrence (p=0.005), distant metastasis (p<0.001), and death (p=0.001). In the multivariate analysis, altered survivin was an independent poor prognostic factor for recurrence.

Conclusions

Unlike in transitional cell carcinoma, alteration of survivin expression in squamous cell carcinoma occurs less frequently and is not associated with features of tumor aggression or patient outcome. These findings raise a question: are urinary bladder carcinoma patients with squamous cell carcinoma type suitable candidates for survivin vaccine? This is an important question to be answered before approving the vaccine in management.

Modelling bladder cancer in mice: opportunities and challenges

The prognosis and treatment of bladder cancer have improved little in the past 20 years. Bladder cancer remains a debilitating and often fatal disease, and is among the most costly cancers to treat. The generation of informative mouse models has the potential to improve our understanding of bladder cancer progression, as well as to affect its diagnosis and treatment. However, relatively few mouse models of bladder cancer have been described, and in particular, few that develop invasive cancer phenotypes. This Review focuses on opportunities for improving the landscape of mouse models of bladder cancer.

The involvement of miR-100 in bladder urothelial carcinogenesis changing the expression levels of mRNA and proteins of genes related to cell proliferation, survival, apoptosis and chromosomal stability

Introduction

MicroRNAs (miRNA) are small non-coding RNAs that play an important role in the control of gene expression by inhibiting protein translation or promoting messenger RNA degradation. Today, miRNAs have been shown to be involved in various physiological and pathological cellular processes, including cancer, where they can act as oncogenes or tumor suppressor genes. Recently, lowered expression of miR-100, resulting in upregulation of FGFR3, has been correlated with low-grade, non-invasive bladder urothelial cancer, as an alternative oncogenesis pathway to the typical FGFR3 gene mutation. Our aim is to analyze the role of miR-100 in bladder cancer cell lines in controlling the expression of some of its possible target genes, including FGFR3 and its relationship with proliferation, apoptosis and DNA ploidy.

Methods

The bladder cancer cell lines RT4 and T24 were transfected with pre-miR 100, anti-miR 100 and their respective controls using a lipid-based formulation. After transfection mRNA and protein levels of its supposed target genes THAP2, BAZ2A, mTOR, SMARCA5 and FGFR3 were analyzed by quantitative real time polymerase chain reaction (qRT-PCR) and western blotting. Cell proliferation, apoptosis and DNA ploidy were analyzed by flow cytometry. For statistical analysis, a t-test was applied, p < 0.05 was considered significant.

Results

After miR-100 transfection, there was a significant reduction in the mRNA of mTOR (p = 0.006), SMARCA5 (p = 0.007) and BAZ2A (p = 0.029) in RT4, mTOR (p = 0.023) and SMARCA5 (p = 0.015) in T24. There was a reduction in the expression of all proteins, variable from 22.5% to 57.1% in both cell lines. In T24 miR-100 promoted an increase in cell proliferation and anti-miR 100 promoted apoptosis characterizing miR-100 as an oncomiR in this cell line representative of a high-grade urothelial carcinoma.

Conclusion

miR-100 transfection reduces expression of BAZ2A, mTOR and SMARCA5 mRNA and protein in BC cell lines. miR-100 would be classified as an oncomiR in T24 cells representative of high grade urothelial carcinoma promoting increase in cell proliferation and reduction in apoptosis. The knowledge of miRNA role in tumors will allow their use as tumor markers and targets for new therapies.

Metabonomic profiling of bladder cancer

Early diagnosis and life-long surveillance are clinically important to improve the long-term survival of bladder cancer patients. Currently, a noninvasive biomarker that is as sensitive and specific as cystoscopy in detecting bladder tumors is lacking. Metabonomics is a complementary approach for identifying perturbed metabolic pathways in bladder cancer. Significant progress has been made using modern metabonomic techniques to characterize and distinguish bladder cancer patients from control subjects, identify marker metabolites, and shed insights on the disease biology and potential therapeutic targets. With its rapid development, metabonomics has the potential to impact the clinical management of bladder cancer patients in the future by revolutionizing the diagnosis and life-long surveillance strategies and stratifying patients for diagnostic, surgical, and therapeutic clinical trials. An introduction to metabonomics, typical metabonomic workflow, and critical evaluation of metabonomic investigations in identifying biomarkers for the diagnosis of bladder cancer are presented.

MiRNA in bladder carcinogenesis: A review

Bladder cancer (BC) is the second urological malignancy in incidence, currently being one of the most neoplasms studied with profile and biology poorly defined. In the world, BC is responsible by about 386000 new cases and 150000 deaths annually with considerable economic impact and high costs for health systems. After its discovery more than 20 years, micro RNAs (miRNAs) have been recognized as molecules that work specifically in post-transcriptional control in majority of eukaryote genomes. MiRNAs are a family of small non-coding RNAs of 19-25 nucleotides in length, expressed in a wide variety of organisms, comprising plants, worms and mammals, including humans. They have a fundamental role in physiological and pathological processes in organs and tissues in a context-dependent manner. This review brings new roles of protective and oncogenic miRNAs linked to carcinogenesis of urothelial carcinoma of the bladder, and associated with behavior of disease. Many studies have demonstrated promising roles of miRNAs working as diagnostic and prognostic biomarkers or involved in target therapies, consolidating miRNAs as crucial players in human cancer. This review allowed a reflection about the true functions of miRNAs in bladder carcinogenesis. Not only by their wide capacities of action, but also by abilities in define the cell date. The future of anti-tumor target therapies will be based not in one, but in groups of miRNAs working together in several steps of carcinogenic process, being able to identify the disease, predicting behavior and effectively treat bladder cancer.

A new tumor suppressor role for the Notch pathway in bladder cancer

The Notch signaling pathway controls cell fates through interactions between neighboring cells by positively or negatively affecting the processes of proliferation, differentiation and apoptosis in a context-dependent manner. This pathway has been implicated in human cancer as both an oncogene and a tumor suppressor. Here we report new inactivating mutations in Notch pathway components in over 40% of human bladder cancers examined. Bladder cancer is the fourth most commonly diagnosed malignancy in the male population of the United States. Thus far, driver mutations in fibroblast growth factor receptor 3 (FGFR3) and, less commonly, in RAS proteins have been identified. We show that Notch activation in bladder cancer cells suppresses proliferation both in vitro and in vivo by directly upregulating dual-specificity phosphatases (DUSPs), thus reducing the phosphorylation of ERK1 and ERK2 (ERK1/2). In mouse models, genetic inactivation of Notch signaling leads to Erk1/2 phosphorylation, resulting in tumorigenesis in the urinary tract. Collectively our findings show that loss of Notch activity is a driving event in urothelial cancer.

miR-19a acts as an oncogenic microRNA and is up-regulated in bladder cancer

Background

The application of microRNAs (miRNAs) as potential biomarkers and therapy targets has been widely investigated in many kinds of cancers. The discovery of tumor associated miRNAs in serum of patients supported the use of plasma/serum miRNAs as noninvasive means of cancer detection. However, the aberrant expression of miRNAs in bladder cancer patients and their intensive roles and mechanisms in bladder cancer are poorly understood.

Methods

Taqman probe stem-loop real-time PCR was used to accurately measure the levels of miR-19a in bladder cancer cell lines, 100 pairs of bladder cancer tissues and the adjacent non-neoplastic tissues and also the plasma collected from bladder cancer patients and normal controls. miR-19a mimics and inhibitors were transfected into bladder cancer cells to investigate its role on regulating cell proliferation which was measured by CCK-8 and colony formation assay. The target of miR-19a was identified by western blot and whether its regulatory role depends on its target was improved by a rescue experiment with miR-19a mimic and PTEN expression plasmid.

Results

miR-19a was significantly up-regulated in bladder cancer tissues and high-level of miR-19a was correlative with more aggressive phenotypes of bladder cancer. Meanwhile, gain or loss of function of miR-19a demonstrated that miR-19a can promote cell growth of bladder cancer cells and the further mechanism studies indicated that its oncogenic role was dependent on targeting PTEN. Furthermore, investigation of miR-19a expression in the plasma of bladder cancer patients showed that miR-19a was also increased in plasma of bladder cancer patients which strongly supported miR-19a could be developed as potential diagnostic marker of bladder cancer.

Conclusions

Our data indicated that miR-19a might act as an oncogenic microRNA in bladder cancer and was significantly up-regulated in bladder cancer carcinogenesis. The oncogenic role of miR19a in bladder cancer was dependent on targeting PTEN.

miR-19a acts as an oncogenic microRNA and is up-regulated in bladder cancer

BACKGROUND

The application of microRNAs (miRNAs) as potential biomarkers and therapy targets has been widely investigated in many kinds of cancers. The discovery of tumor associated miRNAs in serum of patients supported the use of plasma/serum miRNAs as noninvasive means of cancer detection. However, the aberrant expression of miRNAs in bladder cancer patients and their intensive roles and mechanisms in bladder cancer are poorly understood.

METHODS

Taqman probe stem-loop real-time PCR was used to accurately measure the levels of miR-19a in bladder cancer cell lines, 100 pairs of bladder cancer tissues and the adjacent non-neoplastic tissues and also the plasma collected from bladder cancer patients and normal controls. miR-19a mimics and inhibitors were transfected into bladder cancer cells to investigate its role on regulating cell proliferation which was measured by CCK-8 and colony formation assay. The target of miR-19a was identified by western blot and whether its regulatory role depends on its target was improved by a rescue experiment with miR-19a mimic and PTEN expression plasmid.

RESULTS

miR-19a was significantly up-regulated in bladder cancer tissues and high-level of miR-19a was correlative with more aggressive phenotypes of bladder cancer. Meanwhile, gain or loss of function of miR-19a demonstrated that miR-19a can promote cell growth of bladder cancer cells and the further mechanism studies indicated that its oncogenic role was dependent on targeting PTEN. Furthermore, investigation of miR-19a expression in the plasma of bladder cancer patients showed that miR-19a was also increased in plasma of bladder cancer patients which strongly supported miR-19a could be developed as potential diagnostic marker of bladder cancer.

CONCLUSIONS

Our data indicated that miR-19a might act as an oncogenic microRNA in bladder cancer and was significantly up-regulated in bladder cancer carcinogenesis. The oncogenic role of miR19a in bladder cancer was dependent on targeting PTEN.

microRNA-99a acts as a tumor suppressor and is down-regulated in bladder cancer

BACKGROUND

Increasing evidences have documented that microRNAs (miRNAs) act as oncogenes or tumor suppressors in a variety types of cancer. The discovery of tumor associated miRNAs in serum of patients gives rise to extensive investigation of circulating miRNAs in many human cancers which support the use of plasma/serum miRNAs as noninvasive means of cancer detection. However, the aberrant expression of miRNAs and the circulating miRNAs in bladder cancer are less reported.

METHODS

We used Taqman probe stem-loop real-time PCR to accurately measure the levels of miR-99a in bladder cancer cell lines, 100 pairs of bladder cancer tissues, the adjacent non-neoplastic tissues and plasma collected from bladder cancer patients or control patients. miR-99a mimics were re-introduced into bladder cancer cells to investigate its role on regulating cell proliferation which was measured by CCK-8 assay and cell cycle analysis.

RESULTS

miR-99a was significantly down-regulated in bladder cancer tissues, and even the lower expression of miR-99a was correlative with the more aggressive phenotypes of bladder cancer. Meanwhile, enforced expression of miR-99a can inhibit the cell proliferation of bladder cancer cells. Furthermore, investigation of the expression of miR-99a in plasma of bladder cancer patients showed that miR-99a was also decreased in plasma of bladder cancer patients. The results strongly supported miR-99a as the potential diagnostic marker of bladder cancer.

CONCLUSIONS

Our data indicated that miR-99a might act as a tumor suppressor in bladder cancer and was significantly down-regulated in development of bladder cancer.

Fibroblast growth factor receptor 3 activation plays a causative role in urothelial cancer pathogenesis in cooperation with Pten loss in mice

Although somatic mutations and overexpression of the tyrosine kinase fibroblast growth factor receptor 3 (FGFR3) are strongly associated with bladder cancer, evidence for their functional involvement in the pathogenesis remains elusive. Previously we showed that activation of Fgfr3 alone is not sufficient to initiate urothelial tumourigenesis in mice. Here we hypothesize that cooperating mutations are required for Fgfr3-dependent tumourigenesis in the urothelium and analyse a mouse model in which an inhibitor of Pi3k-Akt signalling, Pten, is deleted in concert with Fgfr3 activation (UroIICreFgfr3(+/) (K644E) Pten(flox) (/flox)). Two main phenotypical characteristics were observed in the urothelium: increased urothelial thickness and abnormal cellular histopathology, including vacuolization, condensed cellular appearance, enlargement of cells and nuclei, and loss of polarity. These changes were not observed when either mutation was present individually. Expression patterns of known urothelial proteins indicated the abnormal cellular differentiation. Furthermore, quantitative analysis showed that Fgfr3 and Pten mutations cooperatively caused cellular enlargement, while Pten contributed to increased cell proliferation. Finally, FGFR3 overexpression was analysed along the level of phosphorylated mTOR in 66 T1 urothelial tumours in tissue microarray, which supported the occurrence of functional association of these two signalling pathways in urothelial pathogenesis. Taken together, this study provides evidence supporting a functional role of FGFR3 in the process of pathogenesis in urothelial neoplasms. Given the wide availability of inhibitors specific to FGF signalling pathways, our model may open the avenue for FGFR3-targeted translation in urothelial disease.

Identification of LDH-A as a therapeutic target for cancer cell killing via (i) p53/NAD(H)-dependent and (ii) p53-independent pathways

Most cancer cells use aerobic glycolysis to fuel their growth. The enzyme lactate dehydrogenase-A (LDH-A) is key to cancer's glycolytic phenotype, catalysing the regeneration of nicotinamide adenine dinucleotide (NAD(+)) from reduced nicotinamide adenine dinucleotide (NADH) necessary to sustain glycolysis. As such, LDH-A is a promising target for anticancer therapy. Here we ask if the tumour suppressor p53, a major regulator of cellular metabolism, influences the response of cancer cells to LDH-A suppression. LDH-A knockdown by RNA interference (RNAi) induced cancer cell death in p53 wild-type, mutant and p53-null human cancer cell lines, indicating that endogenous LDH-A promotes cancer cell survival irrespective of cancer cell p53 status. Unexpectedly, however, we uncovered a novel role for p53 in the regulation of cancer cell NAD(+) and its reduced form NADH. Thus, LDH-A silencing by RNAi, or its inhibition using a small-molecule inhibitor, resulted in a p53-dependent increase in the cancer cell ratio of NADH:NAD(+). This effect was specific for p53(+/+) cancer cells and correlated with (i) reduced activity of NAD(+)-dependent deacetylase sirtuin 1 (SIRT1) and (ii) an increase in acetylated p53, a known target of SIRT1 deacetylation activity. In addition, activation of the redox-sensitive anticancer drug EO9 was enhanced selectively in p53(+/+) cancer cells, attributable to increased activity of NAD(P)H-dependent oxidoreductase NQO1 (NAD(P)H quinone oxidoreductase 1). Suppressing LDH-A increased EO9-induced DNA damage in p53(+/+) cancer cells, but importantly had no additive effect in non-cancer cells. Our results identify a unique strategy by which the NADH/NAD(+) cellular redox status can be modulated in a cancer-specific, p53-dependent manner and we show that this can impact upon the activity of important NAD(H)-dependent enzymes. To summarise, this work indicates two distinct mechanisms by which suppressing LDH-A could potentially be used to kill cancer cells selectively, (i) through induction of apoptosis, irrespective of cancer cell p53 status and (ii) as a part of a combinatorial approach with redox-sensitive anticancer drugs via a novel p53/NAD(H)-dependent mechanism.