Epidemiology of urinary bladder cancer: from tumor development to patient’s death

Association between CYP1A2 gene variants -163 C/A (rs762551) and -3860 G/A (rs2069514) and bladder cancer susceptibility

BACKGROUND

Bladder cancer (BLCA) poses a significant global health challenge due to its high incidence, poor prognosis, and limited treatment options.

AIMS AND OBJECTIVES

This study aims to investigate the association between two specific polymorphisms, CYP1A2-163 C/A and CYP1A2-3860G/A, within the Cytochrome P450 1A2 (CYP1A2) gene and susceptibility to BLCA.

METHODS

The study employed a case-control design, genotyping 340 individuals using Polymerase Chain Reaction-High-Resolution Melting Curve (PCR-HRM). Various genetic models were applied to evaluate allele and genotype frequencies. Genetic linkage analysis was facilitated using R packages.

RESULTS

The study reveals a significant association with the - 163 C/A allele, particularly in the additive model. Odds ratio (OR) analysis links CYP1A2-163 C/A (rs762551) and CYP1A2-3860G/A(rs2069514) polymorphisms to BLCA susceptibility. The rs762551 C/A genotype is prevalent in 55% of BLCA cases and exhibits an OR of 2.21. The A/A genotype has an OR of 1.54. Regarding CYP1A2-3860G/A, the G/A genotype has an OR of 1.54, and the A/A genotype has an OR of 2.08. Haplotype analysis shows a predominant C-C haplotype at 38.2%, followed by a C-A haplotype at 54.7%, and a less frequent A-A haplotype at 7.1%. This study underscores associations between CYP1A2 gene variants, particularly rs762551 (CYP1A2-163 C/A), and an increased susceptibility to BLCA. Haplotype analysis of 340 individuals reveals a predominant C-C haplotype at 38.2%, followed by a C-A haplotype at 54.7%, and a less frequent A-A haplotype at 7.1%.

CONCLUSION

In conclusion, the - 163 C/A allele, C/A genotype of rs762551, and G/A genotype of rs2069514 emerge as potential genetic markers associated with elevated BLCA risk.

Revealing the potential of solute carrier family 31 (copper transporters), member 1: Insights into its role in bladder cancer progression and therapeutic implications

Introduction: Bladder cancer represents a significant public health concern with diverse genetic alterations influencing disease onset, progression, and therapy response. In this study, we explore the multifaceted role of Solute Carrier Family 31 Member 1 (SLC31A1) in bladder cancer, a pivotal gene involved in copper homeostasis. Methods: Our research involved analyzing the SLC31A1 gene expression via RT-qPCR, promoter methylation via targeted bisulfite sequencing, and mutational status via Next Generation Sequencing (NGS) using the clinical samples sourced by the local bladder cancer patients. Later on, The Cancer Genome Atlas (TCGA) datasets were utilized for validation purposes. Moreover, prognostic significance, gene enrichment terms, and therapeutic drugs of SLC31A1 were also explored using KM Plotter, DAVID, and DrugBank databases. Results: We observed that SLC31A1 was significantly up-regulated at both the mRNA and protein levels in bladder cancer tissue samples, suggesting its potential involvement in bladder cancer development and progression. Furthermore, our investigation into the methylation status revealed that SLC31A1 was significantly hypomethylated in bladder cancer tissues, which may contribute to its overexpression. The ROC analysis of the SLC31A1 gene indicated promising diagnostic potential, emphasizing its relevance in distinguishing bladder cancer patients from normal individuals. However, it is crucial to consider other factors such as cancer stage, metastasis, and recurrence for a more accurate evaluation in the clinical context. Interestingly, mutational analysis of SLC31A1 demonstrated only benign mutations, indicating their unknown role in the SLC31A1 disruption. In addition to its diagnostic value, high SLC31A1 expression was associated with poorer overall survival (OS) in bladder cancer patients, shedding light on its prognostic relevance. Gene enrichment analysis indicated that SLC31A1 could influence metabolic and copper-related processes, further underscoring its role in bladder cancer. Lastly, we explored the DrugBank database to identify potential therapeutic agents capable of reducing SLC31A1 expression. Our findings unveiled six important drugs with the potential to target SLC31A1 as a treatment strategy. Conclusion: Our comprehensive investigation highlights SLC31A1 as a promising biomarker for bladder cancer development, progression, and therapy.

Causal relationship between smoking status, smoking frequency and bladder cancer: a Mendelian randomization study

BACKGROUND

Smoking is a well-established risk factor for bladder cancer. However, it remained unclear that whether smoke status and smoke frequency increase bladder cancer.

OBJECTIVE

We aim to explore the causal relationship between smoking status, smoking frequency and the risk of bladder cancer by Mendelian randomization.

METHODS

Large sample size of the genome-wide association(GWAS) database of smoking status, smoking frequency and bladder cancer were obtained. Smoking status included never, previous and current whereas smoking frequency included cigarettes smoked per day, number of cigarettes currently smoked daily and pack years of smoking. Six sets of instrumental variables and 78 related single nucleotide polymorphic(SNP) loci were identified (P < 5 × 10-8. Linkage disequilibrium R2 < 0.001). The causal relationship between smoking status and bladder tumor was studied by inverse variance weighted (IVW), weighted median and MR-Egger regression. Sensitivity analysis were also performed.

RESULTS

There is no causal effect from smoke status on bladder cancer risk while significantly positive relationship between smoking frequency on bladder cancer risk were found. IVW results showed that cigarettes smoked per day, number of cigarettes currently smoked daily and pack years of smoking increase bladder cancer (OR 1.001, 95% CI 1.000-1.002, P = 0.047; OR 1.003, 95% CI 1.000-1.005, P = 0.028; OR 1.004, 95% CI 1.001-1.006, P = 0.003). Sensitivity analysis showed that genetic pleiotropy did not bias the results.

CONCLUSION

The results of two sample Mendelian randomization analysis show that there is a positive causal relationship between smoking frequency and the risk of bladder cancer.

Dietary N-nitroso compounds intake and bladder cancer risk: A systematic review and meta-analysis

Bladder cancer is the most common cancer of the urinary tract. While tobacco smoking is responsible for more than half of the bladder cancer cases, occupational exposures is also an established risk factor of bladder cancer. Strong evidence of carcinogenicity of N-nitroso compounds (NOCs) have been provided in animal and human studies, but the target organ of occurring cancer in human including bladder cancer is still obscure. A wide range of NOCs sources surrounded us like diet, drinking water, cigarette smoking, workplace, and indoor air population. We conducted a meta-analysis to elucidate the association between NOCs in drinking water and food source and bladder cancer risk. Ten articles were included after removing the duplicates and irrelevant articles. The majority studies of our meta-analysis was done on women, maybe because of cigarette smoking as a main risk factor among men which is more common among men than women. Although the number of articles was limited our meta-analysis showed no significant association between dietary intakes of NOCs and bladder cancer risk (OR = 0.96, 95% CI = 0.88, 1.05; I2 = 50%, P-value = 0.007), neither subgrouping of NOCS type and source of NOCs nor dose of nitrate and nitrite intake indicated any associations.

Identification of Let-7f-5p as a novel biomarker of recurrence in non-muscle invasive bladder cancer

BACKGROUND

Among patients diagnosed with non-muscle invasive bladder cancer (NMIBC), 30% to 70% experience recurrences within 6 to 12 years of diagnosis. The need to screen for these events every 3 to 6 months and ultimately annually by cystoscopy makes bladder cancer one of the most expensive malignancies to manage.

OBJECTIVE

The purpose of this study was to identify reproducible prognostic microRNAs in resected non-muscle invasive bladder tumor tissue that are predictive of the recurrent tumor phenotype as potential biomarkers and molecular therapeutic targets.

METHODS

Two independent cohorts of NMIBC patients were analyzed using a biomarker discovery and validation approach, respectively.

RESULTS

miRNA Let-7f-5p showed the strongest association with recurrence across both cohorts. Let-7f-5p levels in urine and plasma were both found to be significantly correlated with levels in tumor tissue. We assessed the therapeutic potential of targeting Lin28, a negative regulator of Let-7f-5p, with small-molecule inhibitor C1632. Lin28 inhibition significantly increased levels of Let-7f-5p expression and led to significant inhibition of viability and migration of HTB-2 cells.

CONCLUSIONS

We have identified Let-7f-5p as a miRNA biomarker of recurrence in NMIBC tumors. We further demonstrate that targeting Lin28, a negative regulator of Let-7f-5p, represents a novel potential therapeutic opportunity in NMIBC.

Correlation between immunohistochemical expression of Ki-67and P63 and aggressiveness of urinary bladder urothelial carcinoma

Urothelial carcinoma is the most common urinary malignancy with a wide proportion of cancer morbidity and mortality. The aim of the present study is to evaluate Ki-67 and p63 immunoexpression and their correlation with grade and stage of bladder urothelial carcinoma. Fifty cases of bladder urothelial carcinoma were investigated and were submitted to immunohistochemical staining for p63 and Ki-67, which were assessed qualitatively and quantitatively. A high percentage of p63 immunoexpression showed a significant association with low-grade tumors (P < .05), while Ki-67 mean percentage of expression was higher in high-grade tumors, advanced stage and multiple tumors compared to low grade, early-stage and single tumors without statistical association. Furthermore, the mean percentage of p63 was higher in urothelial carcinoma with squamous differentiation compared to pure urothelial carcinoma with an absence of statistical significance. P63 could help in the identification of bladder tumors with squamous differentiation since identifying these cases is important regarding prognostic and therapeutic aspects. Ki 67 seems to be associated with features of bladder tumor progression as multiplicity, high grade and advanced stage.

Gene-environment interaction with smoking for increased non-muscle-invasive bladder cancer tumor size

Background

Urinary bladder cancer (UBC) is one of few cancers with an established gene-environment interaction (GxE) with smoking. However, it is unknown whether the interaction with tobacco use is present non-muscle invasive bladder cancer (NMIBC) and characteristics of prognostic relevance. We aimed to investigate if smoking status and/or smoking intensity interact with the effect of discovered variants on key NMIBC characteristics of tumor grade, stage, size, and patient age within the Bladder Cancer Prognosis Programme (BCPP) cohort.

Methods

Analyzed sample consisted of 546 NMIBC patients with valid smoking data from the BCPP. In a previous genome-wide association study (GWAS), we have identified 61 single nucleotide polymorphisms (SNPs) potentially associated with the NMIBC characteristics of tumor stage, grade, size, and patient age. In the current analysis, we have tested these SNPs for GxE with smoking.

Results

Out of 61 SNPs, 10 have showed suggestion (statistical significance level of P<0.05) for GxE with NMIBC tumor size rs35225990, rs188958632, rs180910528, rs74603364, rs187040828, rs144383242, rs117587674, rs113705641, rs2937268, and chromosome 14:38247577. All SNPs were located across loci of 1p31.3, 3p26.1, 6q14.1, 14q21.1, and 13q14.13. In addition, two of the tested polymorphisms were suggestive for interaction with smoking intensity (chromosome 14:38247577 and rs2937268).

Conclusions

Our study suggests interaction between genetic variance and smoking behavior for increased NMIBC tumor size at the time of diagnosis. Further replication is required to validate these findings.

Interactions between Cisplatin and Quercetin at Physiological and Hyperthermic Conditions on Cancer Cells In Vitro and In Vivo

Quercetin (QU), a hyperthermic sensitizer, when combined with cisplatin (CP) affects tumor growth. To determine the effects of QU and CP and their interactions, multimodal treatment in vitro and in vivo models under physiological and hyperthermic conditions was performed. In vitro, different sensitivity of T24 and UMUC human bladder cancer cells was observed after short-term exposure to QU (2 h) and CP (1 h). Effects of both compounds were investigated at low and high micromolar concentrations (1 and 50 µM, respectively) under both thermal conditions. QU acted in additive or synergistic manner in combination with CP between physiological condition and hyperthermia. As determined by 3-(4,5-dimethylthiazol2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, short-term application of QU and CP reduced cell viability. Clonal assay also indicated that combined treatment with QU and CP is lethal to bladder cancer cells in both conditions. In vivo, CP (5 or 10 mg kg⁻¹) and QU (50 mg kg⁻¹) acted synergistically with hyperthermia (43 °C) and inhibited tumor growth, activated immune effectors and increased mice survival. Our results demonstrate that combined treatment with CP and QU may increase death of tumor cells in physiological and hyperthermic conditions which could be clinically relevant in locoregional chemotherapy.

Proteolytic parameter changes in the plasma of patients with bladder cancer – depending on tumor stage

Bladder cancer (BC) is a worldwide common disease with a high mortality rate. Recognizing the dynamic changes in plasma that proteases and their inhibitors undergo might be valuable in understanding the carcinogenesis of invasive bladder cancer and in identifying BC patients with poor prognosis. This study aims to determine the activity of the proteolytic enzyme system and their inhibitors in patients with BC. In this paper, the total proteolytic activity, the activity of matrix metalloproteases (MMPs) and serine proteases was analyzed by the method of caseinolytic activity. For detection of activity of some inhibitors of proteolysis, we used the unified method for determining the activity of alpha-1-antitrypsin (α1A) and alpha-2-Macroglobulin (α2M) in human plasma. The level of medium-mass molecules (MMM) was assessed spectrophotometrically by applying the Nikolaichik method.

The activity of MMPs was elevated in all groups of patients. Moreover, the activity of serine proteases was found to be enhanced in patients with Stage I, III and IV BC, while the activity of α1A was up by 1.4 and 1.3 times in patients with Stage I and Stage IV. The most significant increase was observed with regard to the activity of α2M in patients with I and III stages of BC. In addition, the level of MMM correlated with cancer stage. Indeed, the highest increase in the activity of protease inhibitors was observed in Stage I bladder cancer patients, which might signify their protective role at the onset of the bladder carcinogenesis. In contrast, significant growth in activity of α2M in patients with III stage of BC may point at a compensatory mechanism that inhibits tumor growth.

Mitigation of aflatoxin B1- and sodium arsenite-induced cytotoxicities in HUC-PC urinary bladder cells by curcumin and Khaya senegalensis

Background Concomitant exposure to environmental/occupational toxicants such as aflatoxin B1 (AFB1) and arsenic in some regions of the world has been well reported. Therefore, this calls for the assessment of the efficacy of agents such as phytochemicals, which are already known for their ethno-medicinal uses in prophylaxis/remediation. We investigated the possible cytotoxic bio-interactions between AFB1 and sodium arsenite (SA) in urinary bladder cells. We also assessed the cytoprotective effects of curcumin and the ethanol stem bark extract of Khaya senegalensis (K2S). Methods The cells were exposed to graded levels of AFB1, SA, curcumin, and K2S for 24, 48, and 72 h. Subsequently, using optimum toxic concentrations of AFB1 and SA, respectively, the influence of non-toxic levels of curcumin and/or K2S was tested on exposure of the cells to AFB1 and/or SA. Hoechst 33342/propidium iodide staining technique was used to determine the end-points due to cytotoxicity with changes in adenosine triphosphate (ATP) levels determined using Promega's CellTiter-Glo luminescent assay. Results Co-treatment of the cells with AFB1 and SA resulted in synergy in cytotoxic effects. Cytotoxicity was reduced by 3.5- and 2.9-fold by pre-treatment of the cells with curcumin and K2S before treatment with AFB1, while post-treatment resulted in 1.1- and 2.6-fold reduction, respectively. Pre-exposure of the cells with curcumin and K2S before treatment with SA ameliorated cytotoxicity by 3.8- and 3.0-fold, but post-treatment caused a 1.2- and 1.3-fold reduction, respectively. Conclusions Pre-treatment of the cells with either curcumin or K2S exhibited cytoprotective effects by ameliorating AFB1- and SA-induced cytotoxicity with inferred tendencies to prevent carcinogenesis.

Overview of VI-RADS in Bladder Cancer

OBJECTIVE. The purpose of this article is to review the natural history and management of bladder cancer, with insight into MRI applications for the assessment of muscle invasiveness of bladder cancer using the newly developed Vesical Imaging Reporting and Data System (VI-RADS) score. CONCLUSION. Multiparametric MRI and the VI-RADS score have been consistently validated across several different institutions as appropriate tools for local staging of bladder cancer and have been proven to contribute to the diagnostic workup and management of urinary bladder cancer.

Genetic and molecular biology of bladder cancer among Iranian patients

Background

Bladder cancer (BC) is the sixth common cancer among Iranians. Various risk factors such as smoking, body mass index, chronic infection, age, and genetic factors are associated with BC progression.

Methods

It has been shown that a significant ratio of patients have tumors with muscle bladder layer invasion and poor prognosis at the time of diagnosis. Therefore, the early detection of tumors is required to reduce the mortality rate of BC cases. Since there is a wide geographical incidence variation in BC in Iran, it seems that the ethnic and genetic factors can be the main risk factors among Iranian BC patients.

Results

For the first time, in present review we have summarized all of the reported genes among Iranian BC patients until now which were significantly associated with tumorigenesis. Moreover, we categorized all of the reported genes based on their cell and molecular functions to clarify the genetic and molecular biology of BC among Iranian population.

Conclusion

This review paves the way of determination of a population‐based genetic panel markers for the early detection of BC in this population.

Intake of milk and other dairy products and the risk of bladder cancer: a pooled analysis of 13 cohort studies

BACKGROUND

Inconsistent associations between milk and other dairy product consumption and bladder cancer (BC) have been reported. We aimed to investigate possible associations with BC risk for total and individual dairy products by bringing together the world's data on this topic.

METHODS

Thirteen cohort studies, included in the BLadder cancer Epidemiology and Nutritional Determinants (BLEND) study, provided data for 3590 BC cases and 593,637 non-cases. Associations between milk and other dairy product consumption and BC risk were investigated using Cox proportional hazard regression analyses stratified by study center and adjusted for potential confounders.

RESULTS

Overall, total 'other' dairy product consumption was not associated with BC risk (HR comparing highest with lowest tertile: 0.97 (95% CI: 0.87-1.07; ptrend = 0.52) and likewise no association was observed for either liquid milk, processed milk, cream, cheese or icecream. However, an inverse association was observed between yoghurt consumption and BC risk when comparing those in the moderate (25-85 g/day) and high categories (>85 g/day) with non-consumers, with multivariate HR of 0.85 (95% CI: 0.75-0.96) and 0.88 (95% CI: 0.78-0.98), respectively.

CONCLUSIONS

We found no evidence of association between either total or individual dairy products and BC risk, but suggestive evidence that consumption of yoghurt may be associated with a decreased risk.

Prognostic Role of Epithelial-Mesenchymal Transition Markers "E-Cadherin, β-Catenin, ZEB1, ZEB2 and p63" in Bladder Carcinoma

Background

This study aimed to investigate the expression of epithelial-mesenchymal markers’ E-cadherin, β-catenin, zinc-finger E-box-binding homeobox 1 (ZEB1), zinc-finger E-box-binding homeobox 2 (ZEB2) and p63 in transitional cell carcinoma (TCC) and squamous cell carcinoma (SCC) variants of bladder carcinoma (BC) and their correlation with clinicopathological parameters of prognostic importance.

Methods

In this retrospective study, 91 patients were enrolled (66 with TCC and 25 with SCC). All patients had full clinical and follow-up data and available paraffin blocks. Immunohistochemical analysis was performed and correlated with clinicopathological factors.

Results

In TCC cases, reduced E-cadherin, β-catenin positivity and p63 expression rate were evident in the sitting of increased expression of ZEB1 and ZEB2. Patients with ZEB2 positive tumors were more likely to die compared to those with negative ZEB2 (P = 0.024). Moreover, in patients with muscle-invasive BCs, an intense p63 expression was associated with poor overall survival (OS) (P < 0.001). For patients with SCC, there was a reduction in E-cadherin and β-catenin positivity with elevated p63 expression and concomitant increased ZEB1 and ZEB2 expression. Poor prognosis was evident in association with reduced E-cadherin, positive nuclear β-catenin/reduced membranous β-catenin, ZEB1 and ZEB2 positive cases as well patients with elevated p63 expression (P < 0.001). TCC and SCC cases showed similar poor prognosis in association with elevated p63 expression (P < 0.001).

Conclusions

In both TCC and SCC variants, epithelial-mesenchymal transition (EMT) process is evident; however, its molecular mechanism shows some variations, specifically this notably different p63 expression pattern among two carcinoma variants with the similar impact of elevated p63 expression pattern on prognosis.

Apaziquone for Nonmuscle Invasive Bladder Cancer: Where Are We Now?

Apaziquone is an interesting drug for intravesical use in patients with nonmuscle invasive bladder cancer; however, more research is needed to prove its actual benefit. Although the apaziquone trials demonstrate the potential of this new drug, the singular phase 3 trials did not reach their primary endpoint. To date, no new trials are recruiting, so the development of apaziquone seems to have stopped.

In silico design and in vitro characterization of a recombinant antigen for specific recognition of NMP22

Although urine cytology and cystoscopy are current gold standard methods in diagnosis and surveillance of Bladder cancer (BC), they have some limitations which necessitates novel diagnostic approaches to compensate their drawbacks. In this regard, Nuclear Matrix Protein 22 (NMP22) is introduced as a potential tumor biomarker for BC detection (FDA approved). NMP22 determination mainly occurs through immunoassay platforms, raising a proper antibody against its antigen. Hence, development of such immunoassays seems crucial. Various bioinformatic tools were harnessed to select a region with lowest variability, highest density for linear and conformational epitopes, lowest post translational modifications, highest antigenicity, best physicochemical properties and reliable transcriptional properties. Subsequently, E. coli BL21 (DE3) and P. pastoris GS115 were applied for exogenous expression. Ultimately, protein purification and quantification was followed by ELISA test for antibody analyses. Both host successfully expressed the antigen, while the E. coli expression was with higher yield. The commercial anti-NMP22 antibodies showed relatively equal detection results. However, the slight better detection for the antigen with P. pastoris origin could be deduced as better structural properties for P. pastoris. These results indicate higher expression yields and lower costs for over-expression of this eukaryotic antigen.

Peptidyl Arginine Deiminase, Type II (PADI2) Is Involved in Urothelial Bladder Cancer

Peptidyl arginine deiminase, type II (PADI2) expression has been shown to potentiate multiple different carcinogenesis pathway including breast carcinoma and spontaneous skin neoplasia. The objective of this study was to examine the role of PADI2 in urothelial bladder cancer which has not been evaluated previously. Analysis of mutation and genome amplification of bladder cancer within The Cancer Genome Atlas (TCGA) showed that PADI2 is both mutated and amplified in a cohort of bladder cancer patients, with the largest number of mutations detected in urothelial bladder cancer. Even though PADI2 expression was not significantly correlated to survival in bladder cancer patients, it was significantly overexpressed at the mRNA and protein levels, as revealed by TCGA data and immunohistochemistry analysis, respectively. PADI2 showed wide expression pattern in bladder cancer tissues but was hardly detected in tumor adjacent normal tissue. RNAi mediated silencing of PADI2 in the bladder cancer cell line T24 did not result in a change of proliferation. Interestingly knockdown of PADI2 expression did not affect Snail1 protein, which is associated with metastatic progression, in these cells. However, PADI2 silencing remarkably attenuated both in vitro migration and invasion- in T24 cells indicating a Snail1-independent effect of PADI2 on invasive potential of urothelial bladder cancer. This was further corroborated by in vivo xenograft assays where PADI2 shRNA harboring T24 cells did not have detectable tumors by week 4 as compared to robust tumors in the control Luciferase shRNA harboring cells. PADI2 silencing did not affect proliferation rates and hence this would suggest that PADI2 knockdown is perhaps causing increased apoptosis as well as transition through the cell cycle, which needs to be confirmed in future studies. Our results reveal a yet undefined role of PADI2 as an oncogene in urothelial bladder cancer.

A review of incidence and mortality of colorectal, lung, liver, thyroid, and bladder cancers in Iran and compared to other countries

In Iran, a developing country in southwest Asia, an epidemiologic transition is underway from communicable to noncommunicable diseases. In Iran, cancer is the second largest group of chronic non-communicable diseases (NCDs) and the third most common cause of death following heart disease, accidents and other natural phenomena. There are some studies reporting an increasing trend in the incidence and mortality rate of a variety of cancers in Iran. Therefore, controlling and preventive interventions pertaining to cancers must be a main priority for health policy and it is recommended that the high-risk population receive earlier screening. In this review, incidence and mortality of colorectal, lung, liver, thyroid, and bladder cancers in Iran are reported.

MicroRNA Dysregulation and Non-Muscle-Invasive Bladder Cancer Prognosis

BACKGROUND

The high rate of non-muscle-invasive bladder cancer recurrence is a major challenge in patient management. miRNAs functionally regulate tumor cell proliferation and invasion, and have strong potential as biomarkers because they are robust to degradation. The objective of this project was to identify reproducible prognostic miRNAs in resected non-muscle-invasive bladder tumor tissue that are predictive of the recurrent tumor phenotype.

METHODS

We utilized patients diagnosed with primary non-muscle-invasive bladder cancer in three independent cohorts for a biomarker discovery/validation approach. Baseline tumor tissue from patients with the clinically challenging, non-muscle-invasive primary low stage (Ta), high grade, and T1 tumors (tumors extending into the lamina propria) comprised the discovery cohort (n = 38). We isolated the tumor tissue RNA and assessed a panel of approximately 800 miRNAs.

RESULTS

miR-26b-5p was the top-ranking prognostic tumor tissue miRNA, with a time-to-recurrence HR 0.043 for levels above versus below median, (P _adj = 0.0003). miR-26b-5p was related to a dose-response reduction in tumor recurrence, and levels above the median were also associated with reduced time-to-progression (P _adj = 0.02). We used two independent longitudinal cohorts that included both low-grade and high-grade Ta and T1 tumors for validation and found a consistent relationship between miR-26b-5p and recurrence and progression.

CONCLUSIONS

Our results suggest that miR-26b-5p levels may be prognostic for non-muscle-invasive bladder cancer recurrence, and can feasibly be assessed in baseline tumor tissue from a wide variety of clinical settings.

IMPACT

Early identification of those non-muscle-invasive bladder tumor patients with refractory phenotypes would enable individualized treatment and surveillance.

lncRNA MIR503HG functioned as a tumor suppressor and inhibited cell proliferation, metastasis and epithelial-mesenchymal transition in bladder cancer

Bladder cancer is the most common malignancy with high recurrence. Currently, the long noncoding RNAs (lncRNAs) have been suggested to play vital roles in the pathogenesis of bladder cancer. The present study investigated the role of lncRNA MIR503 host gene (MIR503HG) in the pathogenesis of bladder cancer by using both in vitro and in vivo functional assays. The expression of MIR503HG was downregulated in bladder cancer tissues and cell lines. Low expression of MIR503HG was associated with advanced tumor stage, advanced histological grade, and lymph node metastasis. Ectopic expression of MIR503HG inhibited cell proliferation, cell growth, cell invasion, and migration, and also promoted cell apoptosis and inhibited cell cycle progression in SW780 cells. In parallel, T24 cells were used for loss-of-function studies. Knockdown of MIR503HG promoted the cancer cell proliferation and increased the migration and invasion abilities of T24 cells. In addition, knockdown of MIR503HG reduced the cell apoptotic rate in cancer cells and promoted cell cycle progression. Furthermore, MIR503HG overexpression decreased the epithelial-mesenchymal transition-related mRNA and protein levels of ZEB1, Snail, N-cadherin, and vimentin, with an increase in E-cadherin level. Consistently, knockdown of MIR503HG showed the opposite effects. In vivo xenograft, nude mice results showed that overexpression of MIR503HG suppressed the tumor growth and tumor metastasis. In conclusion, our results identified a novel lncRNA MIR503HG that exhibited significant antiproliferation, antimigration/invasion effects on bladder cancer cells both in vitro and in vivo, which may hold a therapeutic promise to treat bladder cancer.

Urinary Bladder Tumors Clinical and Statistical Retrospective Study

Nowadays, urinary bladder cancer represents a major health problem, due to very high medical and social costs. This disease affects mainly the elderly. We performed a study on 1073 patients admitted to the Urology Clinic within the Emergency Clinical Hospital of Craiova, between 2013-2015 with bladder cancer. Of the 1073 cases, 741(69.06%) were diagnosed in men, and 332 (30.94%) were found in women, the men/ women ratio being of 2.23/1. The highest incidence of bladder tumors was recorded in individuals aged between 60 and 79 years old. In this age group, there were admitted 734 patients with bladder cancer, representing 68.44%. Regarding the tumor recurrence, out of 1073 bladder tumors, a number of 608 (56.66%) patients were diagnosed with primary tumors, while a number of 465 (43.34%) patients presented recurrent tumors. Of the symptoms presented by the patients, the most frequent were haematuria (present in about 87% of the patients), pollakiuria (present in 64% of the patients), dysuria (present in 55% of the patients) and urinary infections (present in about 23% of the patients).

The prognostic impact of incidental prostate cancer following radical cystoprostatectomy: a nationwide analysis

BACKGROUND

To determine the prevalence and prognostic impact of incidental prostate cancer in patients undergoing radical cystoprostatectomy.

METHODS

A nationwide population-based study of incidental prostate cancer diagnosed following radical cystoprostatectomy. Information on vital status, Gleason score, positive and negative tumor margins, pT-category and subsequent prostate cancer therapies were obtained from the Danish Prostate Cancer Registry and by manual chart review.

RESULTS

A total of 1,450 men who underwent radical cystoprostatectomy in Denmark from 1995-2011 were identified. Forty-six men were excluded from analysis, thus 1,404 patients were eligible. The median follow-up was 7.8 years. A total of 466 (33.2%) had incidental prostate cancer diagnosed. No statistical differences in 10- and 15-year cumulative overall mortality were observed when comparing men with, or without, incidental prostate cancer. In men diagnosed with incidental prostate cancer, neither Gleason score, positive surgical margins or locally advanced prostate cancer (pT3-4) was associated with mortality. Only 0.9% received post-operative prostate cancer-related treatment.

CONCLUSION

In this population-based cohort of patients with incidental prostate cancer diagnosed at radical cystoprostatectomy, we found no impact of incidental prostate cancer on overall mortality, regardless of Gleason score, surgical margin status and pathological T-category. Patients diagnosed with incidental prostate cancer following radical cystoprostatectomy are unlikely to benefit from additional follow-up.

Targeted and Untargeted Detection of DNA Adducts of Aromatic Amine Carcinogens in Human Bladder by Ultra-Performance Liquid Chromatography-High-Resolution Mass Spectrometry

Epidemiological studies have linked aromatic amines (AAs) from tobacco smoke and some occupational exposures with bladder cancer risk. Several epidemiological studies have also reported a plausible role for structurally related heterocyclic aromatic amines present in tobacco smoke or formed in cooked meats with bladder cancer risk. DNA adduct formation is an initial biochemical event in bladder carcinogenesis. We examined paired fresh-frozen (FR) and formalin-fixed paraffin-embedded (FFPE) nontumor bladder tissues from 41 bladder cancer patients for DNA adducts of 4-aminobiphenyl (4-ABP), a bladder carcinogen present in tobacco smoke, and 2-amino-9 H-pyrido[2,3- b]indole, 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine and 2-amino-3,8-dimethylimidazo[4,5- f]quinoxaline, possible human carcinogens, which occur in tobacco smoke and cooked meats. These chemicals are present in urine of tobacco smokers or omnivores. Targeted DNA adduct measurements were done by ultra-performance liquid chromatography-electrospray ionization multistage hybrid Orbitrap MS. N-(2'-Deoxyguanosin-8-yl)-4-ABP ( N-(dG-C8)-4-ABP) was the sole adduct detected in FR and FFPE bladder tissues. Twelve subjects (29%) had N-(dG-C8)-4-ABP levels above the limit of quantification, ranging from 1.4 to 33.8 adducts per 109 nucleotides (nt). DNA adducts of other human AA bladder carcinogens, including 2-naphthylamine (2-NA), 2-methylaniline (2-MA), 2,6-dimethylaniline (2,6-DMA), and lipid peroxidation (LPO) adducts, were screened for in bladder tissue, by our untargeted data-independent adductomics method, termed wide-selected ion monitoring (wide-SIM)/MS2. Wide-SIM/MS2 successfully detected N-(dG-C8)-4-ABP, N-(2'-deoxyadenosin-8-yl)-4-ABP and the presumed hydrazo linked adduct, N-(2'-deoxyguanosin- N2-yl)-4-ABP, and several LPO adducts in bladder DNA. Wide-SIM/MS2 detected multiple DNA adducts of 2-NA, 2-MA, and, 2,6-DMA, when calf thymus DNA was modified with reactive intermediates of these carcinogens. However, these AA-adducts were below the limit of detection in unspiked human bladder DNA (<1 adduct per 108 nt). Wide-SIM/MS2 can screen for many types of DNA adducts formed with exogenous and endogenous electrophiles and will be employed to identify DNA adducts of other chemicals that may contribute to the etiology of bladder cancer.

Bladder Cancer in Lebanon: Incidence and Comparison to Regional and Western Countries

Lebanon has one of the highest estimated age-standardized incidence rate (ASR(w)) of bladder cancer (BC) worldwide. The aim of this study is to analyze the incidence rates for BC in Lebanon over a period of 7 years and to compare them to the rates in other countries. Data were obtained from the Lebanese National Cancer Registry for the currently available years 2005 to 2011. The calculated ASR(w) and age-specific rates were expressed as per 100 000 population. From 2005 to 2011, BC has been ranked as the third most common cancer in Lebanon. It accounted for 9.0% of all newly diagnosed cancer cases excluding nonmelanoma skin cancer. It ranked second in males and ninth in females. The average ASR(w) over this period was 31.2 in men and 7.3 in women. These incidence rates are among the highest worldwide across all age groups in both sexes. This study shows that the incidence of BC in Lebanon is high and it is among the highest worldwide. It is important to reduce the risk of BC through tobacco control and by decreasing exposure to avoidable environmental and occupational risk factors.

High expression of spindle and kinetochore- associated protein 1 predicts early recurrence and progression of non-muscle invasive bladder cancer

BACKGROUND

Spindle and kinetochore-associated protein 1 (SKA1) is a component of SKA, which is essential for proper chromosome segregation. Recently, SKA1 was found to be over-expressed in several types of human cancers. However, reports on the relationship between SKA1 expression and the prognosis of bladder cancer, in particular, are lacking.

OBJECTIVES

To clarify the clinical significance of SKA1 as a prognostic biomarker for early recurrence and progression of patients with non-muscle invasive bladder cancer (NMIBC).

METHODS

The differential expression levels of SKA1 of 148 NMIBC tissues were determined by immunohistochemical staining. Quantitative real-time PCR and western blot analysis were further performed to confirm the immunohistochemistry results. Recurrence and progression free interval were assessed by Kaplan-Meier method and differences between groups calculated by log-rank statistics. The prognostic value of SKA1 for early recurrence and progression was analyzed by multivariate Cox proportional hazard regression models.

RESULTS

SKA1 expression was significantly different in various NMIBC tissues. Kaplan-Meier analysis revealed that patients with high SKA1 expression showed high early recurrence (p< 0.001) and progression (p< 0.05) rates. Although univariate Cox regression analysis revealed that several other factors had an impact on recurrence and progression, upon multivariate analysis, high SKA1expression was the only independent predictor for early recurrence (hazards ratio [HR], 0.246; 95% confidence interval [CI], 0.131-0.461; p= 0.000) and progression (HR, 0.194; 95% CI, 0.052-0.715; p= 0.014).

CONCLUSIONS

High SKA1 expression is associated with early recurrence and progression in patients with NMIBC, indicating SKA1 may serve as a promising prognostic biomarker for this disease.

Increased CD4+ T cell lineage commitment determined by CpG methylation correlates with better prognosis in urinary bladder cancer patients

Background

Urinary bladder cancer is a common malignancy worldwide. Environmental factors and chronic inflammation are correlated with the disease risk. Diagnosis is performed by transurethral resection of the bladder, and patients with muscle invasive disease preferably proceed to radical cystectomy, with or without neoadjuvant chemotherapy. The anti-tumour immune responses, known to be initiated in the tumour and draining lymph nodes, may play a major role in future treatment strategies. Thus, increasing the knowledge of tumour-associated immunological processes is important. Activated CD4⁺ T cells differentiate into four main separate lineages: Th1, Th2, Th17 and Treg, and they are recognized by their effector molecules IFN-γ, IL-13, IL-17A, and the transcription factor Foxp3, respectively. We have previously demonstrated signature CpG sites predictive for lineage commitment of these four major CD4⁺ T cell lineages. Here, we investigate the lineage commitment specifically in tumour, lymph nodes and blood and relate them to the disease stage and response to neoadjuvant chemotherapy.

Results

Blood, tumour and regional lymph nodes were obtained from patients at time of transurethral resection of the bladder and at radical cystectomy. Tumour-infiltrating CD4⁺ lymphocytes were significantly hypomethylated in all four investigated lineage loci compared to CD4⁺ lymphocytes in lymph nodes and blood (lymph nodes vs tumour-infiltrating lymphocytes: IFNG -4229 bp p < 0.0001, IL13 -11 bp p < 0.05, IL17A -122 bp p < 0.01 and FOXP3 -77 bp p > 0.05). Examination of individual lymph nodes displayed different methylation signatures, suggesting possible correlation with future survival. More advanced post-cystectomy tumour stages correlated significantly with increased methylation at the IFNG -4229 bp locus. Patients with complete response to neoadjuvant chemotherapy displayed significant hypomethylation in CD4⁺ T cells for all four investigated loci, most prominently in IFNG p < 0.0001. Neoadjuvant chemotherapy seemed to result in a relocation of Th1-committed CD4⁺ T cells from blood, presumably to the tumour, indicated by shifts in the methylation patterns, whereas no such shifts were seen for lineages corresponding to IL13, IL17A and FOXP3.

Conclusion

Increased lineage commitment in CD4⁺ T cells, as determined by demethylation in predictive CpG sites, is associated with lower post-cystectomy tumour stage, complete response to neoadjuvant chemotherapy and overall better outcome, suggesting epigenetic profiling of CD4⁺ T cell lineages as a useful readout for clinical staging.

Electronic supplementary material

The online version of this article (10.1186/s13148-018-0536-6) contains supplementary material, which is available to authorized users.

Enhancer RNA - P2RY2e induced by estrogen promotes malignant behaviors of bladder cancer

Enhancers are transcriptional regulatory elements that increase target gene expression. It has reported that enhancers could universally transcribe into enhancer RNAs (eRNAs) with stimulation. Increasing evidence showed eRNAs participated in various disease processes including malignant tumors. P2RY2 enhancer RNA (P2RY2e) is an estrogen-responsive eRNA and involved in the development of breast cancer. However, the relationship between P2RY2e and bladder cancer (BCa) is unclear. In the study, we discovered that P2RY2e was upregulated in BCa tissues and estrogen-treated cells. Estrogen promoted the malignant abilities of BCa cells. P2RY2e knockdown by CRISPR-Cas13a inhibit the cell multiplication, invasion and migration. Additionally, the cell apoptosis was facilitated. What's more, downregulation of P2RY2e could weaken the cancer-promoting effects of estrogen on BCa. Our study revealed that P2RY2e played a carcinogenic role in BCa and estrogen might promote the initiation of BCa by inducing P2RY2e. We provide a potential therapeutic target for BCa and a new perspective for the tumorigenesis of bladder cancer.

Pioglitazone use in patients with diabetes and risk of bladder cancer: a systematic review and meta-analysis

Pioglitazone has been reported to increase the risk of bladder cancer but the conclusions of published clinical studies are confusing. We conducted a systematic review and meta-analysis of all eligible randomized controlled trial (RCT) studies and observational studies, in order to identify a more precise relationship between pioglitazone and risk of bladder cancer. We searched for publications up to January 24, 2018, in PubMed, EMBASE, Scopus, Web of Science, Cochrane register, and Chinese National Knowledge Infrastructure databases, and the references of the retrieved articles and relevant reviews were also checked. Relative risk and 95% confidence interval (CI) were used to assess this correlation. A dose-related meta-analysis was performed as well. Data on RCT studies showed a null association between pioglitazone and bladder cancer. The pooled RR estimates of the 12 included studies illustrated that pioglitazone is associated with a 14% increased risk of bladder cancer (95% CI 1.03-1.26). No evidence of publication bias was detected. In the dose effect analysis, patients who used a higher dose of pioglitazone had an increased risk of bladder cancer. In conclusion, this meta-analysis indicated that pioglitazone is associated with an increased risk of bladder cancer. Further research should be conducted to confirm our findings and reveal the potential biological mechanisms.

Differential expression of cytokeratin 14 and 18 in bladder cancer tumorigenesis

It has been previously suggested that cytokeratins (CKs) are important diagnostic and prognostic biomarkers for urothelial lesions. Hence it is imperative to understand the expression pattern of cytokeratins during formation of papillary bladder cancer, which was the objective of the current study. Expression pattern of CK14 and CK18 were examined using immunohistochemical staining in a mice model of papillary bladder cancer. Twenty female mice were divided into two groups-group 1 (NT) and group 2, which received N-butyl- N-(4-hydroxybutyl) nitrosamine (BBN) for 20 weeks plus one week without treatment. Following histological classification of bladder lesions, CK14 and CK18 immunostaining was assessed according to its distribution and intensity. In NT animals, both basal cells and umbrella cells showed sporadic positive staining for CK14 and CK18, respectively. In BBN group, hyperplastic lesions showed significantly more CK14 and significantly less CK18 staining ( P < 0.05 in each case). Invasive carcinomas showed increased CK14 immunostaining in all epithelial layers. Cumulatively, our data indicate that altered CK14 (high) and CK18 (low) expression is perhaps an early event in bladder cancer tumorigenesis in females at least and is characteristic of both urothelial superficial pre-neoplastic and neoplastic lesions. Impact statement Studies have shown that expression of cytokeratins (CKs) or their altered distribution affects the bladder cancer pathogenesis and disease outcome, while the underlying mechanisms are not clear. The present study aims to explore the expression pattern of CK14 and CK18 during formation of papillary bladder cancer. The results showed that hyperplastic lesions showed significantly more CK14 and significantly less CK18 staining and invasive carcinomas showed increased CK14 immunostaining in all epithelial layers in N-butyl- N-(4-hydroxybutyl)nitrosamine (BBN)-induced mouse model. The results indicate that altered CK14 (high) and CK18 (low) expression is perhaps an early event in bladder cancer tumorigenesis and is characteristic of both urothelial superficial pre-neoplastic and neoplastic lesions, which may provide the early diagnosis index.

Environment and bladder cancer: molecular analysis by interaction networks

Bladder cancer (BC) is the 9th most common cancer worldwide, and the 6th most common cancer in men. Its development is linked to chronic inflammation, genetic susceptibility, smoking, occupational exposures and environmental pollutants. Aim of this work was to identify a sub-network of genes/proteins modulated by environmental or arsenic exposure in BC by computational network approaches. Our studies evidenced the presence of HUB nodes both in "BC and environment" and "BC and arsenicals" networks. These HUB nodes resulted to be correlated to circadian genes and targeted by some miRNAs already reported as involved in BC, thus suggesting how they play an important role in BC development due to environmental or arsenic exposure. Through data-mining analysis related to putative effect of the identified HUB nodes on survival we identified genes/proteins and their mutations on which it will be useful to focus further experimental studies related to the evaluation of their expression in biological matrices and to their utility as biomarkers of BC development.

Long noncoding RNA GAS5 inhibits malignant proliferation and chemotherapy resistance to doxorubicin in bladder transitional cell carcinoma

PURPOSE

Bladder cancer is the most general malignant cancer in genitourinary system, more than 90% of BCs are bladder transitional cell carcinomas (BTCC). This study aimed to investigate the clinical significance of growth arrest-specific 5 (GAS5) gene and its regulatory effects of malignant proliferation and chemotherapy resistance to doxorubicin in BTCC cells.

METHODS

The expression of GAS5 was detected by quantitative real-time PCR. Statistical analysis was used to determine the relationship between GAS5 expression and clinical features and the prognostic value of GAS5 for disease free survival. MTT assay was used to detect cell proliferation ability and chemosensitivity. Dual-color flow cytometric method was used to detect cell apoptosis. The expression of Bcl-2 protein was examined by western blot.

RESULTS

In this study, we found that GAS5 low-expressed in BTCC tissues and cells, and its low expression level had positive correlation with higher pathological grades of BTCC. Moreover, GAS5 was a prognostic biomarker of disease free survival for BTCC patients. GAS5 over-expression could inhibit cell proliferation of BTCC J82 and T24 cells significantly. The IC50 to doxorubicin in T24/DOX cells (resistance to doxorubicin) presented a conspicuous depression, GAS5 enhancement reduced the chemotherapy resistance to doxorubicin. GAS5 over-expression promoted apoptosis induced by doxorubicin in T24/DOX cells, and depressed the expression of anti-apoptosis protein Bcl-2. The results indicated that GAS5 regulated the chemotherapy resistance to doxorubicin via Bcl2 partly.

CONCLUSIONS

In summary, lncRNA GAS5 was a prognostic biomarker of disease free survival in BTCC patients, and acted as a tumor-suppressing gene to inhibit malignant proliferation and resistance to doxorubicin in BTCC cells. LncRNA GAS5 might be a novel potential therapeutic target for BTCC.

Red and processed meat consumption and risk of bladder cancer: a dose-response meta-analysis of epidemiological studies

Background/objectives

Several epidemiological studies have analyzed the associations between red and processed meat and bladder cancer risk but the shape and strength of the associations are still unclear. Therefore, we conducted a dose–response meta-analysis to quantify the potential association between red and processed meat and bladder cancer risk.

Methods

Relevant studies were identified by searching the PubMed database through January 2016 and reviewing the reference lists of the retrieved articles. Results were combined using random-effects models.

Results

Five cohort studies with 3262 cases and 1,038,787 participants and 8 cases–control studies with 7009 cases and 27,240 participants met the inclusion criteria. Red meat was linearly associated with bladder cancer risk in case–control studies, with a pooled RR of 1.51 (95% confidence interval (CI) 1.13, 2.02) for every 100 g increase per day, while no association was observed among cohort studies (P heterogeneity across study design = 0.02). Based on both case–control and cohort studies, the pooled relative risk (RR) for every 50 g increase of processed meat per day was 1.20 (95% CI 1.06, 1.37) (P heterogeneity across study design = 0.22).

Conclusions

This meta-analysis suggests that processed meat may be positively associated with bladder cancer risk. A positive association between red meat and risk of bladder cancer was observed only in case–control studies, while no association was observe in prospective studies.

Electronic supplementary material

The online version of this article (doi:10.1007/s00394-016-1356-0) contains supplementary material, which is available to authorized users.

Parity, Age at First Birth, and Risk of Death from Bladder Cancer: A Population-Based Cohort Study in Taiwan

The evidence is limited on the relationship between reproductive factors and bladder cancer (BC). We studied 1,292,462 women who had a first and singleton delivery between 1 January 1978 and 31 December 1987. Each woman in the study cohort was tracked from their first childbirth to 31 December 2009. Vital status of the women was determined by crosswalking records with a computerized mortality database. We used Cox proportional hazard regression models to estimate the hazard ratios (HRs) of death from BC associated with maternal age at first birth and parity. The data showed 63 BC deaths during 34,980,246 person-years of follow-up. BC mortality rate was 0.90 cases for every 100,000 person-years. Compared with women who gave birth under the age of 23, the adjusted HR was 1.24 (95% confidence interval (CI) = 0.66–2.35) for women who gave birth between age 23 and 26 and 2.30 (95% CI = 1.21–4.39) for women who gave birth over the age of 26. Increasing age at first birth (p for trend = 0.01) is associated with a trend in increasing risk of BC mortality. Relative to women who had a single childbirth, the adjusted HRs were 1.17 (95% CI = 0.51–2.69) for women who gave birth to two children, and 1.31 (95% CI = 0.56–3.10) for women with three or more childbirths, respectively. These results were not statistically significant. Study results suggests that giving birth at an early age may confer a protective effect on the risk of death from BC.

Comparison between standard and reduced volume radiotherapy in bladder preservation trimodality protocol for muscle-invasive bladder cancer patients

Aim

Our aim is to compare the toxicity, pelvic nodal relapse, and overall survival of whole bladder irradiation only to the standard technique of whole pelvis irradiation followed by bladder boost in patients with muscle-invasive bladder carcinoma undergoing bladder preservation protocol.

Material and method

A total of 60 patients with transitional cell carcinoma, stage T2-3, N0, M0 bladder cancer were subjected to maximal transurethral resection bladder tumour (TURB). Then, the patients were randomised into two groups: group I (30 patients) to receive whole pelvis radiotherapy 44 Gy followed by 20 Gy bladder boost. While group II (30 patients) were randomised to receive whole bladder radiotherapy alone for a total dose of 64 Gy. In both groups, concomitant cisplatin and paclitaxel were given weekly throughout the whole course of radiotherapy where conventional 2 Gy/fraction were used. Additionally, four cycles of adjuvant cisplatin and paclitaxel were given after the end of the chemoradiotherapy induction course.

Results

The first assessment after the induction chemoradiotherapy showed that complete response was achieved in 73.3% of patients in group I and 76.7% of the patients in group II. After a median follow-up of 2 years, regional relapse occurred in 7.1% of patients in group I and 10.3% in group II. (p = 1). Distant metastases were detected in 17.9% of patient in group I and 13.8% in group II (p = 0.73). The 2-year disease-free survival was 60% in group I and 63.3% in group II (p = 0.79). The whole 2-year overall survival was 75% in group I and 79.3% in group II (p = 0.689). Radiation gastrointestinal (GI) acute toxicity was higher in group I than in group II (p = 0.001), while late GI radiation toxicity was comparable in both groups.

Conclusion

Treating the bladder only, without elective pelvic nodal irradiation, did not compromise pelvic control rate, but significantly decreased the acute radiation toxicity.

Significant association of catechol-O-methyltransferase Val158Met polymorphism with bladder cancer instead of prostate and kidney cancer

BACKGROUND

Urological cancers occur worldwide. Many factors, among which the catechol-O-methyltransferase (COMT) Val158Met polymorphism, are said to be associated with the cancer risk. We conducted a meta-analysis to investigate the association between urological cancer susceptibility and COMT Val158Met in different genetic models.

METHODS

This study was based on material obtained from the PubMed, HuGENet and Embase databases. Four models including dominant (AA + AG vs. GG), recessive (AA vs. AG + GG), codominant (AA vs. AG, AA vs. GG) and per-allele analysis (A vs. G) were applied. Odds ratios (OR) and the corresponding 95% confidence intervals (CI) were used to evaluate the power of the associations.

RESULTS

Fourteen eligible studies comprising 3,285 cases and 3,594 controls were included. Although we could not detect a positive function of the COMT Val158Met polymorphism in urological cancers, the polymorphism might be significantly associated with bladder cancer risk (dominant model [AA + AG vs. GG]: OR = 0.736, 95% CI = 0.586-0.925, I2 = 0.00%; recessive model [AA vs. AG + GG]: OR = 0.822, 95%CI = 0.653-1.035, I2 = 6.30%; codominant model [AA vs. AG]: OR = 0.908, 95% CI = 0.710-1.161, I2 = 0.00%; codominant model [AA vs. GG]: OR = 0.693, 95% CI = 0.524-0.917, I2 = 30.20%; allele analysis [A vs. G]: OR = 0.826, 95%CI = 0.717-0.951, I2 = 30.20%). The same significant associations were not found for kidney cancer and prostate cancer risk in different ethnicities. There also seemed to be no distinct effect of the polymorphism on benign prostatic hyperplasia.

CONCLUSIONS

We suggest that bladder cancer but not prostate cancer and kidney cancer could be significantly associated with the Val158Met polymorphism. Interaction of COMT genetic and related environmental factors for urological cancers should not be ignored in future.

Human Neural Stem Cells Overexpressing a Carboxylesterase Inhibit Bladder Tumor Growth

Bladder cancer is a significant clinical and economic problem. Despite intravesical chemotherapy and immunotherapy, up to 80% of patients with non-muscle-invasive bladder cancer develop recurrent tumors, of which 20% to 30% evolve into more aggressive, potentially lethal tumors. Recently, bladder cancer cells are considered to be mediators of resistance to current therapies and therefore represent strong candidates as biologic targets. No effective chemotherapy has yet been developed for advanced bladder cancer. It is desirable that a drug can be delivered directly and specifically to bladder cancer cells. Stem cells have selective migration ability toward cancer cells, and therapeutic genes can be easily transduced into stem cells. In suicide gene therapy for cancer, stem cells carry a gene encoding a carboxylesterase (CE) enzyme that transforms an inert CPT-11 prodrug into a toxic SN-38 product, a topoisomerase 1 inhibitor. In immunodeficient mice, systemically transplanted HB1.F3.CE stem cells migrated toward the tumor implanted by the TCCSUP bladder cancer cell line, and, in combination with CPT-11, the volume of tumors was significantly reduced. These findings may contribute to the development of a new selective chemotherapeutic strategy against bladder cancer. Mol Cancer Ther; 15(6); 1201-7. ©2016 AACR.

Small-area spatio-temporal analyses of bladder and kidney cancer risk in Nova Scotia, Canada

BACKGROUND

Bladder and kidney cancers are the ninth and twelfth most common type of cancer worldwide, respectively. Internationally, rates vary ten-fold, with several countries showing rising incidence. This study describes the spatial and spatio-temporal variations in the incidence risk of these diseases for Nova Scotia, a province located in Atlantic Canada, where rates for bladder and kidney cancer exceed those of the national average by about 25% and 35%, respectively.

METHODS

Cancer incidence in the 311 Communities of Nova-Scotia was analyzed with a spatial autoregressive model for the case counts of bladder and kidney cancers (3,232 and 2,143 total cases, respectively), accounting for each Community's population and including variables known to influence risk. A spatially-continuous analysis, using a geostatistical Local Expectation-Maximization smoothing algorithm, modeled finer-scale spatial variation in risk for south-western Nova Scotia (1,810 bladder and 957 kidney cases) and Cape Breton (1,101 bladder, 703 kidney).

RESULTS

Evidence of spatial variations in the risk of bladder and kidney cancer was demonstrated using both aggregated Community-level mapping and continuous-grid based localized mapping; and these were generally stable over time. The Community-level analysis suggested that much of this heterogeneity was not accounted for by known explanatory variables. There appears to be a north-east to south-west increasing gradient with a number of south-western Communities have risk of bladder or kidney cancer more than 10% above the provincial average. Kidney cancer risk was also elevated in various northeastern communities. Over a 12 year period this exceedance translated in an excess of 200 cases. Patterns of variations in risk obtained from the spatially continuous smoothing analysis generally mirrored those from the Community-level autoregressive model, although these more localized risk estimates resulted in a larger spatial extent for which risk is likely to be elevated.

CONCLUSIONS

Modelling the spatio-temporal distribution of disease risk enabled the quantification of risk relative to expected background levels and the identification of high risk areas. It also permitted the determination of the relative stability of the observed patterns over time and in this study, pointed to excess risk potentially driven by exposure to risk factors that act in a sustained manner over time.

Correlation between XRCC1 Arg399Gln genetic polymorphisms and susceptibility to bladder cancer: a meta-analysis

The relationship between XRCC1 polymorphisms and bladder cancer has been widely studied. Here, our meta-analysis was conducted to evaluate the correlations between common genetic polymorphisms in XRCC1 and susceptibility to bladder cancer. In order to derive a more precise estimation of the association, 27 clinical case-control studies (which met all the inclusion criteria) were included in this meta-analysis. A total of 8,539 cancer cases and 10,750 controls were involved in this meta-analysis. Overall, no significant association was detected in allelic model (A allele vs T allele odds ratio [OR] =0.87, 95% confidence interval [CI], 0.71–1.06), homozygote comparison (AA vs GG OR =1.12, 95% CI, 0.68–1.85), heterozygote comparison (AT vs TT OR =1.01, 95% CI, 0.81–1.26), dominant model (AA + AG vs GG OR =0.93, 95% CI, 0.85–1.02), and recessive model (AA vs AG + GG OR =1.01, 95% CI, 0.88–1.15), but a moderately significant association was found for AG vs GG (OR =0.241, 95% CI =0.17–0.35). Subgroup analysis based on ethnicity. Ethnicity analysis suggested that genetic polymorphisms in XRCC1 were not correlated with increased bladder cancer risk among Asians (all P>0.05). Therefore, we concluded that XRCC1 genetic polymorphism may not contribute to bladder cancer susceptibility in the present meta-analysis, and further well-designed studies with a large sample size are warranted to validate our conclusion.

"Lassie," "Toto," and fellow pet dogs: poised to lead the way for advances in cancer prevention

Cancer causes substantial morbidity and takes the lives of over 8 million people worldwide each year. Advances in cancer prevention research are crucial, and animal models are key to this. There are many valuable experimentally induced cancer models, but these do not fully meet the needs for cancer prevention studies. Pet dogs with risks for naturally occurring cancer can fill important gaps in cancer prevention research. Using invasive urothelial carcinoma (iUC) as an example, the advantages of utilizing pet dogs include: (1) close similarities between dogs and humans in carcinogenesis, molecular and cellular features, invasive and metastatic behavior, and response to treatment, thus providing high relevance for comparative studies, (2) shared environment between dogs and humans to help identify not-yet-known environmental iUC risks, (3) strong breed-associated risk (5- to 21-fold increased risk compared with mixed breeds) that facilitates investigation of gene-environment interactions, screening, and early intervention, (4) large size of dogs (versus rodents) that allows collection of fluids and tissues via cystoscopy, and detailed imaging at multiple time points, and (5) acceptance for studies in which each participating dog can benefit while enjoying life in their family environment, and in which findings will help other dogs and humans. An ongoing 3-year study in Scottish Terriers (comparable to a 15- to 20-year study in humans) is aimed at defining genetic and environmental risk factors for iUC, effective methods for screening/early detection, and a successful secondary cancer prevention approach with very promising results to date. Pet dogs can indeed propel cancer prevention research.

Knockout of phospholipase Cε attenuates N-butyl-N-(4-hydroxybutyl) nitrosamine-induced bladder tumorigenesis

Bladder cancer frequently shows mutational activation of the oncogene Ras, which is associated with bladder carcinogenesis. However, the signaling pathway downstream of Ras remains to be fully elucidated. N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) is able to induce bladder cancer by driving the clonal expansion of initiated cells carrying the activated form of Ras. Phospholipase Cε (PLCε) is the main target of BBN, while the tumor promoting role of PLCε remains controversial. The present study examined the role of PLCε in BBN-induced bladder carcinogenesis of mice with genetically inactivated PLCε. Using light and electron microscopy, the present study demonstrated that PLCε^−/− mice were resistant to BBN-induced bladder carcinogenesis. Furthermore, it was demonstrated that cyclooxygenase 2 and vascular endothelial growth factor-A were affected by the PLCε background of the mice, suggesting that the role of PLCε in tumor promotion may be ascribed to augmentation of inflammatory responses and angiogenesis. These results indicated that PLCε is crucial for BBN-induced bladder carcinogenesis as well as signaling downstream of Ras, and that PLCε is a candidate molecular target for the development of anti-cancer drugs.

Epidemiology of bladder cancer

Bladder cancer incidence is higher in old men, shows geographic variation, and is mostly an environmental disease. Cigarette smoking, occupational exposures, water arsenic, Schistosoma haematobium infestation, and some medications are the best established risk factors. Low-penetrance genetic factors also contribute to its origin, some through interaction with environmental factors. Bladder cancer has high prevalence and a low mortality, being largely a chronic disease. Data on environmental and genetic factors involved in the disease outcome are inconclusive.