Bladder cancer risk from occupational and environmental exposures

Environmental and occupational exposures and prognosis in patients with non-muscle-invasive bladder cancer in the Be-Well Study

Bladder cancer is primarily diagnosed as non-muscle-invasive bladder cancer (NMIBC), with high recurrence and progression rates. Environmental and occupational exposures to carcinogens are well-known risk factors for developing bladder cancer, yet their effects on prognosis remain unknown. In the Be-Well Study, a population-based prospective cohort study of 1472 Kaiser Permanente patients newly diagnosed with NMIBC in California from 2015 to 2019, we examined history of environmental and occupational exposures in relation to tumor stage and grade at initial diagnosis by multivariable logistic regression, and subsequent recurrence and progression by Cox proportional hazards regression. Exposure to environmental and occupational carcinogens was significantly associated with increased risk of progression (hazard ratio (HR) = 1.79; 95% CI, 1.04-3.09), specifically with increased progression to muscle-invasive disease (HR = 2.28; 95% CI, 1.16-4.50). Exposures to asbestos and arsenic were associated with increased odds of advanced stage at diagnosis (asbestos: odds ratio (OR) = 1.43 [95% CI, 1.11-1.84]; arsenic: OR = 1.27 [95% CI, 1.01-1.63]), and formaldehyde exposure was associated with increased risk of recurrence (HR = 1.38; 95% CI, 1.12-1.69). Our findings suggest that considering a patient's history of these exposures may benefit current risk stratification systems in better tailoring clinical care and improving prognosis among patients with NMIBC.

Social Determinants of Cancer Disparities

Cancer is a major public health issue that is associated with significant morbidity and mortality across the globe. At its root, cancer represents a genetic aberration, but socioeconomic, environmental, and geographic factors contribute to different cancer outcomes for selected population subsets. The disparities in the delivery of healthcare affect all aspects of cancer management from early prevention to end-of-life care. In an effort to address the inequality in the delivery of healthcare among socioeconomically disadvantaged populations, the World Health Organization defined social determinants of health (SDOH) as conditions in which people are born, live, work, and age. These factors play a significant role in the disproportionate cancer burden among different population groups. SDOH are associated with disparities in risk factor burden, screening modalities, diagnostic testing, treatment options, and quality of life of patients with cancer. The purpose of this article is to describe a more holistic and integrated approach to patients with cancer and address the disparities that are derived from their socioeconomic background.

How Does Environmental and Occupational Exposure Contribute to Carcinogenesis in Genitourinary and Lung Cancers?

Environmental and occupational exposures have been associated with an increased risk of different types of cancers, although the exact mechanisms of higher carcinogenesis risk are not always well understood. Lung cancer is the leading cause of global cancer mortality, and, also, genitourinary neoplasms are among the main causes of cancer-related deaths in Western countries. The purpose of this review is to describe the main environmental and occupational factors that increase the risk of developing lung and genitourinary cancers and to investigate carcinogenesis mechanisms that link these agents to cancer onset. Further objectives are to identify methods for the prevention or the early detection of carcinogenic agents and, therefore, to reduce the risk of developing these cancers or to detect them at earlier stages.

Bacteria for Treatment: Microbiome in Bladder Cancer

The human body contains a variety of microbes. The distribution of microbes varies from organ to organ. Sequencing and bioinformatics techniques have revolutionized microbial research. Although previously considered to be sterile, the urinary bladder contains various microbes. Several studies have used urine and bladder tissues to reveal the microbiome of the urinary bladder. Lactic acid-producing bacteria, such as Bifidobacterium, Lactobacillus, and Lactococcus, are particularly beneficial for human health and are linked to bladder cancer. This review highlights the analysis protocols for microbiome research, the studies undertaken to date, and the microbes with therapeutic potential in bladder cancer.

Molecular Oncology of Bladder Cancer from Inception to Modern Perspective

Within the last forty years, seminal contributions have been made in the areas of bladder cancer (BC) biology, driver genes, molecular profiling, biomarkers, and therapeutic targets for improving personalized patient care. This overview includes seminal discoveries and advances in the molecular oncology of BC. Starting with the concept of divergent molecular pathways for the development of low- and high-grade bladder tumors, field cancerization versus clonality of bladder tumors, cancer driver genes/mutations, genetic polymorphisms, and bacillus Calmette-Guérin (BCG) as an early form of immunotherapy are some of the conceptual contributions towards improving patient care. Although beginning with a promise of predicting prognosis and individualizing treatments, "-omic" approaches and molecular subtypes have revealed the importance of BC stem cells, lineage plasticity, and intra-tumor heterogeneity as the next frontiers for realizing individualized patient care. Along with urine as the optimal non-invasive liquid biopsy, BC is at the forefront of the biomarker field. If the goal is to reduce the number of cystoscopies but not to replace them for monitoring recurrence and asymptomatic microscopic hematuria, a BC marker may reach clinical acceptance. As advances in the molecular oncology of BC continue, the next twenty-five years should significantly advance personalized care for BC patients.

Development, regeneration and tumorigenesis of the urothelium

The urothelium of the bladder functions as a waterproof barrier between tissue and outflowing urine. Largely quiescent during homeostasis, this unique epithelium rapidly regenerates in response to bacterial or chemical injury. The specification of the proper cell types during development and injury repair is crucial for tissue function. This Review surveys the current understanding of urothelial progenitor populations in the contexts of organogenesis, regeneration and tumorigenesis. Furthermore, we discuss pathways and signaling mechanisms involved in urothelial differentiation, and consider the relevance of this knowledge to stem cell biology and tissue regeneration.

Geographic distribution of racial differences in mortality in muscle-invasive bladder cancer patients: an opportunity for improvement

OBJECTIVES

To determine the geographic distribution of muscle-invasive bladder cancer mortality according to race in the United States (US). African Americans (AAs) have up to two times the risk of bladder cancer mortality compared to Caucasians. Bladder cancer mortality increases exponentially once it invades the muscle. Geographic heterogeneity in bladder cancer mortality according to race remains to be determined.

DESIGN

Analysis of Surveillance, Epidemiology, and End Results (SEER)-Medicare data for 6,044 patients aged 66-85 diagnosed with clinical stage T2-T4 N0M0 bladder cancer from 1 January 2002 to 31 December 2011. Fine and Gray-competing risks regression models were used to assess the association of race with bladder cancer-specific mortality (BCSM) according to tumor registry.

RESULTS

Out of 6,044 patients, 5,408 (89.5%) were Caucasian, 352 (5.82%) were non-Hispanic AA, 85 (1.4%) were Hispanic, and 199 (3.29%) were other. Of the 18 registries, AAs with bladder cancer were largely concentrated in Louisiana (19%), New Jersey (17.9%), and Georgia (17.6%). New Jersey was the only registry where AAs had increased risk of BCSM than Caucasians and only for stage T2 disease: (AHR, 1.74; 95% CI 1.22-2.47, p = 0.002). According to treatment, AAs in New Jersey had worse BCSM than Caucasians when they underwent radical cystectomy (AHR, 2.05; 95% CI 1.26-3.35, p = 0.0039) and radiotherapy or chemotherapy alone (AHR, 1.55; 95% CI 1.03-2.35, p = 0.0367).

CONCLUSIONS

We observed geographic variation in bladder cancer mortality which impacted only one registry with one of the largest population of AAs. These findings support further investigation into the social determinants of race (i.e., socioeconomic status and distance to healthcare facility) and culturally centered healthcare decision making which may drive these results.

A 25-year perspective on evaluation and understanding of biomarkers in urologic cancers

The past 25 years have witnessed an explosion of investigative attempts to identify clinically useful biomarkers which can have meaningful impacts for patients with urologic cancers. However, in spite of the enormous amount of research aiming to identify markers with the hope of impacting patient care, only a handful have proven to have true clinical utility. Improvements in targeted imaging, pan-omics evaluation, and genetic sequencing at the tissue and single-cell levels have yielded many potential targets for continued biomarker investigation. This article, as one in this series for the 25th Anniversary Issue of Urologic Oncology: Seminars and Original Investigations, serves to give a perspective on our progress and failures over the past quarter-century in our highest volume urologic cancers: prostate, bladder, and kidney cancers.

The efficacy of public health information for encouraging radon gas awareness and testing varies by audience age, sex and profession

Radioactive radon inhalation is a leading cause of lung cancer and underlies an ongoing public health crisis. Radon exposure prevention strategies typically begin by informing populations about health effects, and their initial efficacy is measured by how well and how fast information convinces individuals to test properties. This communication process is rarely individualized, and there is little understanding if messages impact diverse demographics equally. Here, we explored how 2,390 people interested in radon testing differed in their reaction to radon's public health information and their subsequent decision to test. Only 20% were prompted to radon test after 1 encounter with awareness information, while 65% required 2-5 encounters over several months, and 15% needed 6 to > 10 encounters over many years. People who most delayed testing were more likely to be men or involved in engineering, architecture, real estate and/or physical science-related professions. Social pressures were not a major factor influencing radon testing. People who were the least worried about radon health risks were older and/or men, while negative emotional responses to awareness information were reported more by younger people, women and/or parents. This highlights the importance of developing targeted demographic messaging to create effective radon exposure prevention strategies.

Younger North Americans are exposed to more radon gas due to occupancy biases within the residential built environment

Residential buildings can concentrate radioactive radon gas, exposing occupants to particle radiation that increases lung cancer risk. This has worsened over time in North America, with newer residences containing greater radon. Using data from 18,971 Canadian households, we calculated annual particle radiation dose rates due to long term residential radon exposure, and examined this as a function of occupant demographics. The current particle radiation dose rate to lungs from residential radon in Canada is 4.08 mSv/y from 108.2 Bq/m³, with 23.4% receiving 100–2655 mSv doses that are known to elevate human cancer risk. Notably, residences built in the twenty-first century are occupied by significantly younger people experiencing greater radiation dose rates from radon (mean age of 46 at 5.01 mSv/y), relative to older groups more likely to occupy twentieth century-built properties (mean age of 53 at 3.45–4.22 mSv/y). Newer, higher radon-containing properties are also more likely to have minors, pregnant women and an overall higher number of occupants living there full time. As younger age-of-exposure to radon equates to greater lifetime lung cancer risk, these data reveal a worst case scenario of exposure bias. This is of concern as, if it continues, it forecasts serious future increases in radon-induced lung cancer in younger people.

Pegylated Recombinant Human Arginase 1 Induces Autophagy and Apoptosis via the ROS-Activated AKT/mTOR Pathway in Bladder Cancer Cells

Bladder cancer is one of the most commonly diagnosed cancers worldwide, especially in males. Current therapeutic interventions, including surgery, radiation therapy, chemotherapy, and immunotherapy, have not been able to improve the clinical outcome of bladder cancer patients with satisfaction. Recombinant human arginase (rhArg, BCT-100) is a novel agent with great anticancer effects on arginine-auxotrophic tumors. However, the effects of BCT-100 on bladder cancer remain unclear. In this study, the in vitro anticancer effects of BCT-100 were assessed using four bladder cancer cell lines (J82, SCaBER, T24, and 5637), while the in vivo effects were evaluated by establishing T24 nude mice xenograft models. Intracellular arginine level was observed to be sharply decreased followed by the onset of apoptotic events. Furthermore, BCT-100 was found to induce H2O2 production and mitochondrial membrane depolarization, leading to the release of mitochondrial cytochrome c and Smac to the cytosol. Treatment with BCT was observed to upregulate the expression of LC3B and Becllin-1, but downregulate the expression of p62 in a time-dependent manner. Autophagic flux was also observed upon BCT-100 treatment. Besides, the phosphorylation of the AKT/mTOR pathway was suppressed in a time-dependent fashion in BCT-100-treated T24 cells. While N-acetyl-L-cysteine was shown to alleviate BCT-100-induced apoptosis and autophagy, chloroquine, MK-2206, and rapamycin were found to potentiate BCT-100-triggered apoptosis. Finally, BCT-100 was demonstrated to induce autophagy and apoptosis via the ROS-mediated AKT/mTOR signaling pathway in bladder cancer cells.

The Scope of Astrocyte Elevated Gene-1/Metadherin (AEG-1/MTDH) in Cancer Clinicopathology: A Review

Since its initial cloning in 2002, a plethora of studies in a vast number of cancer indications, has strongly established AEG-1 as a bona fide oncogene. In all types of cancer cells, overexpression and knockdown studies have demonstrated that AEG-1 performs a seminal role in regulating proliferation, invasion, angiogenesis, metastasis and chemoresistance, the defining cancer hallmarks, by a variety of mechanisms, including protein-protein interactions activating diverse oncogenic pathways, RNA-binding promoting translation and regulation of inflammation, lipid metabolism and tumor microenvironment. These findings have been strongly buttressed by demonstration of increased tumorigenesis in tissue-specific AEG-1 transgenic mouse models, and profound resistance of multiple types of cancer development and progression in total and conditional AEG-1 knockout mouse models. Additionally, clinicopathologic correlations of AEG-1 expression in a diverse array of cancers establishing AEG-1 as an independent biomarker for highly aggressive, chemoresistance metastatic disease with poor prognosis have provided a solid foundation to the mechanistic and mouse model studies. In this review a comprehensive analysis of the current and up-to-date literature is provided to delineate the clinical significance of AEG-1 in cancer highlighting the commonality of the findings and the discrepancies and discussing the implications of these observations.

Predictive value of β-catenin in bladder cancer: a systematic review and meta-analysis

Recently, some studies have suggested that the abnormal expression of β-catenin in bladder cancer (BC) is associated with the progression and survival of BC, but there are still some controversies. Hence, we elaborated on the relationship between β-catenin expression and BC through a systematic literature review and meta-analysis. As of March 2020, Embase, PubMed, the Cochrane Library, Science Direct/Elsevier, Medline and CNKI were used for systematic literature retrieval to investigate the correlation between β-catenin expression and BC. Meta-analysis was performed using Review Manager and Stata software. Fourteen studies were included, including 865 BC tissues and 106 controls. Combined ORs were identified with 95% confidence intervals (95% CIs) in a random- or fixed-effects model. We illustrated that there was a significant correlation between β-catenin and BC, that there was abnormally high expression of β-catenin in BC tissues compared with normal bladder tissues (P<0.05), and that the combined OR was 14.69 [5.73, 37.65]. Furthermore, the aberrant expression rates of β-catenin in high-grade and invasive bladder neoplasm tissues were greater than those in low-grade and non-muscle-invasive bladder tissues (P<0.05), and the combined ORs were 0.31 [0.23, 0.43] and 0.21 [0.15, 0.29]. Finally, we found through meta-analysis that the higher the expression level of β-catenin, the shorter was the progression-free survival (PFS) of patients with BC (P<0.05), and the combined OR was 2.74 [1.22, 6.14]. The present study suggests that the abnormal expression of β-catenin is associated with aggressive behavior and poor prognosis of BC, and β-catenin may be a molecular marker of the malignant degree and poor prognosis of BC.

Elevated exposure to polycyclic aromatic hydrocarbons (PAHs) may trigger cancers in Pakistan: an environmental, occupational, and genetic perspective

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic compounds which are emitted through incomplete combustion of organic materials, fossil fuels, consumption of processed meat, smoked food, and from various industrial activities. High molecular mass and mobility make PAHs widespread and lethal for human health. A cellular system in human detoxifies these toxicants through specialized enzymatic machinery called xenobiotic-metabolizing (CYP450) and phase-II (GSTs) enzymes (XMEs). These metabolizing enzymes include cytochromes P450 family (CYP1, CYP2), glutathione s-transferases, and ALDHs. Gene polymorphisms in XMEs encoding genes can compromise their metabolizing capacity to detoxify ingested carcinogens (PAHs etc.) that may lead to prolong and elevated exposure to ingested toxicants and may consequently lead to cancer. Moreover, PAHs can induce cancer through reprograming XMEs' gene functions by altering their epigenetic markers. This review article discusses possible interplay between individual's gene polymorphism in XMEs' genes, their altered epigenetic markers, and exposure to PAHs in cancer susceptibility in Pakistan.

Development and validation of a nomogram to predict the prognosis of patients with squamous cell carcinoma of the bladder

Background: The present study aimed to develop and validate a nomogram based on expanded TNM staging to predict the prognosis for patients with squamous cell carcinoma of the bladder (SCCB).

Methods: A total of 595 eligible patients with SCCB identified in the Surveillance, Epidemiology, and End Results (SEER) dataset were randomly divided into training set (n = 416) and validation set (n = 179). The likelihood ratio test was used to select potentially relevant factors for developing the nomogram. The performance of the nomogram was validated on the training and validation sets using a C-index with 95% confidence interval (95% CI) and calibration curve, and was further compared with TNM staging system.

Results: The nomogram included six factors: age, T stage, N stage, M stage, the method of surgery and tumor size. The C-indexes of the nomogram were 0.768 (0.741–0.795) and 0.717 (0.671–0.763) in the training and validation sets, respectively, which were higher than the TNM staging system with C-indexes of 0.580 (0.543–0.617) and 0.540 (0.484–0.596) in the training and validation sets, respectively. Furthermore, the decision curve analysis (DCA) proved that the nomogram provided superior clinical effectiveness.

Conclusions: We developed a nomogram that help predict individualized prognosis for patients with SCCB.

Identification of the Key Factors Related to Bladder Cancer by lncRNA-miRNA-mRNA Three-Layer Network

Bladder cancer is the most common malignant tumor of the urinary system, and it has high incidence, high degree of malignancy, and easy recurrence after surgery. The etiology and pathogenesis of bladder cancer are not fully understood, but more and more studies have shown that its development may be regulated by some core molecules. To identify key molecules in bladder cancer, we constructed a three-layer network by merging lncRNA-miRNA regulatory network, miRNA-mRNA regulatory network, and lncRNA-mRNA coexpression network, and further analyzed the topology attributes of the network including the degree, betweenness centrality and closeness centrality of nodes. We found that miRNA-93 and miRNA-195 are controllers for a three-layer network and regulators of numerous target genes associated with bladder cancer. Functional enrichment analysis of their target mRNAs revealed that miRNA-93 and miRNA-195 may be closely related to bladder cancer by disturbing the homeostasis of the cell cycle or HTLV-I infection. In addition, since E2F1 and E2F2 are enriched in various KEGG signaling pathways, we conclude that they are important target genes of miRNA-93, and participate in the apoptotic process by forming a complex with a certain protein or transcription factor activity, sequence-specific DNA binding in bladder cancer. Similarly, AKT3 is an important target gene of miRNA-195, its expression is associated with PI3K-Akt-mTOR signaling pathway and AMPK-mTOR signaling pathway. Therefore, we speculate that AKT3 may participate in proliferation and apoptosis of bladder cancer cells through these pathways, and ultimately affect the biological behavior of tumor cells. Furthermore, through survival analysis, we found that miRNA-195 and miRNA-93 are associated with poor prognosis of bladder cancer. And the Kaplan-Meier curve showed that 24 mRNAs and nine lncRNAs are closely related to overall survival of bladder cancer.

Scented Candles as an Unrecognized Factor that Increases the Risk of Bladder Cancer; Is There Enough Evidence to Raise a Red Flag?

The causes of bladder cancer are not yet fully uncovered, however the research has identified a number of factors that may increase the risk of developing this cancer. The chemical carcinogenesis of bladder cancer due to chronic exposure to aromatic hydrocarbons has been well-established. The identification of this correlation led to an improvement of safety measures in chemical industry and a gradual decrease of bladder cancer cases among workers. Nevertheless, in the majority of bladder cancer cases, the specific cause of the disease still can't be specified. It makes the question of unrecognized factors associated with bladder cancer development even more relevant. Taking under consideration known chemical carcinogenesis of bladder cancer, this minireview takes under investigation the possible link between using scented candles and a risk of bladder cancer development. Burning scented candles contain many of the substances that are associated with a bladder cancer. Furthermore the scented candles are not only very popular but also widely available on the market, with limited quality regulations and unspecified raw materials determining a spectrum of potentially dangerous substances emitted during burning.

Contribution of prostate stem cell antigen variation rs2294008 to the risk of bladder cancer

OBJECTIVE

Number of studies have been performed to evaluate the relationship between prostate stem cell antigen (PSCA) variation rs2294008 and bladder cancer risk, but the sample size was small and the results were conflicting. This meta-analysis was conducted to comprehensively evaluate the overall association.

METHODS

Pubmed, Web of science, Embase, China biology medical literature database (CBM), China National Knowledge Infrastructure (CNKI), Wan Fang and Weipu databases were searched before June 30, 2018. The strength of associations was assessed using odds ratios (ORs) and 95% confidence intervals (CIs). All of the statistical analyses were conducted using Review Manager 5.3 and Stata 14.0.

RESULTS

Ten studies involved 14,021 cases and 26,871 controls. Overall, significant association was observed between the PSCA gene variant rs2294008 polymorphism and bladder cancer (T vs C: OR = 1.16, 95%CI = 1.12-1.20; TT vs CC: OR = 1.32, 95%CI = 1.24-1.41; TT vs CT+CC: OR = 1.15, 95%CI = 1.09-1.22; TT+CT vs CC: OR = 1.27, 95%CI = 1.21-1.34). In subgroup analysis by ethnic group, a statistically significant association was observed in Asians (T vs C: OR = 1.23, 95%CI = 1.15-1.31) and Caucasians (T vs C: OR = 1.14, 95%CI = 1.10-1.18). The sensitivity analysis confirmed the reliability and stability of the meta-analysis.

CONCLUSION

Our meta-analysis supports that the PSCA gene variant rs2294008 polymorphism might contribute to individual susceptibility to bladder cancer.

Low molecular weight proteins and enzymes in the urine of patients with bladder cancer - a pilot study

Introduction

A steady increase in cases of bladder cancer (BC) has been observed. Detection of unfavorable changes, especially in the early stages of disease, is crucial to medical procedure. There is still a need to search for new, non-invasive biomarkers of BC. The aim of this study was to estimate the levels of selected low molecular weight proteins (LMWP) and enzymes in the urine of patients at different BC stages and grades.

Material and methods

Urine samples from 46 patients with BC and 16 healthy controls were examined. We measured levels of LMWP such as: retinol-binding protein (RBP), β2 -microglobulin (β2M), enzymes: N-acetyl-β-D-glucosaminidase (NAG), isoform (NAG-B) and also neutrophil gelatinase-associated lipocalin (NGAL).

Results

The levels of all examined parameters differed between patients and healthy subjects. Levels of NAG (p = 0.031), NAG-B (p = 0.023) and NGAL (p = 0.008), and total protein (p = 0.007) concentrations, were significantly higher in the BC patients than in the control group. Among the examined parameters, positive significant correlations were observed only between urinary NGAL concentration and tumor stages and grades. The highest percentages of changes in NGAL concentration were observed in tumor in situ (TIS) and G3grade patients.

Conclusions

Our study showed that urinary NGAL concentrations, as well as NAG and NAG-B activity, could be helpful noninvasive parameters for the diagnosis of BC. The most promising seems to be NGAL determination, but further study is needed on a larger group of participants in order to confirm this observation.

Association of CYP2E1 gene polymorphisms with bladder cancer risk: A systematic review and meta-analysis

BACKGROUND

Human cytochrome P450 (CYP) is an enzyme responsible for the metabolic activation of many carcinogens, including nitrosamines. CYP2E1 represents a major CYP isoform and is expressed in the human urothelial cells. Recent studies have investigated the association of CYP2E1 gene polymorphisms with bladder cancer risk but have shown contradictory results. Hence, we performed a systematic literature review and meta-analysis to assess the association between CYP2E1 gene polymorphisms and bladder cancer.

METHODS

Systematic literature searches were conducted with PubMed, Excerpt Medica Database, Science Direct/Elsevier, China National Knowledge Infrastructure, and the Cochrane Library up to January 2018 for studies that involved the association of CYP2E1 gene polymorphisms with bladder cancer risk. A meta-analysis was performed with Review Manager and Stata software. Combined odds ratios (ORs) were identified with 95% confidence intervals (CIs) in a random or fixed effects model.

ETHICS

The protocol was approved by the institutional review board of each study center. Written informed consent will be obtained from all patients before registration, in accordance with the Declaration of Helsinki.

RESULTS

Eight studies were identified, including 1733 cases of bladder cancer and 1814 normal controls. Our results illustrated that there are significant associations between CYP2E1 gene polymorphisms and bladder cancer in all genetic models (P < .05). The combined ORs and 95% CIs were as follows for each model: additive model [OR 0.56; 95% CI (0.38-0.82)]; dominant model [OR 0.79; 95% CI (0.67-0.93)]; recessive model [OR 0.61; 95% CI (0.41-0.89)]; codominant model [OR 0.80; 95% CI (0.67-0.96)]; allele model [OR 0.75; 95% CI (0.59-0.95)]. A subgroup study showed that there are also significant associations between CYP2E1 gene polymorphisms and bladder cancer in Asian people. However, there are no significant associations between CYP2E1 gene polymorphisms and bladder cancer in Caucasian populations.

CONCLUSIONS

The present study provides evidence for an association between CYP2E1 gene polymorphisms and bladder cancer progression, and suggests that CYP2E1 gene polymorphisms might be a protective factor against bladder cancer in Asian people. However, studies with larger sample sizes are needed to confirm the correlation between CYP2E1 gene polymorphisms and bladder cancer.

Accuracy and Readability of Websites on Kidney and Bladder Cancers

The aim of this study was to assess the scientific accuracy and the readability level of websites on kidney and bladder cancers. The search engines Google™, Yahoo™ and Bing™ were searched independently by assessors in November 2014 using the following keywords: "bladder cancer", "kidney cancer", "patient bladder cancer", "patient kidney cancer" and "bladder and kidney cancer". Only English-language websites were selected on the bases of predetermined inclusion and exclusion criteria. Assessors independently reviewed the findings and evaluated the accuracy and quality of each website by using the DISCERN and the LIDA instruments. The readability of the websites was calculated using the Flesch-Kincaid Grade Level Index and the Coleman-Liau Readability Index. Sixty-two websites were finally included in the study. The overall accuracy scores varied; for the DISCERN, the range was 28 to 76; out of 80 (mean ± SD, 47.1 ± 12.1; median = 46.0, interquartile range (IQR) = 19.2), and for the LIDA, the range was 52 to 125; out of 144 (mean ± SD, 101.9 ± 15.2; median, 103; IQR, 16.5). The creators of these websites were universities and research centres (n = 25, 40%), foundations and associations (n = 10, 16%), commercial and pharmaceutical companies (n = 13, 21%), charities and volunteer work (n = 4, 6%) and non-university educational bodies (n = 10, 16%). The readability scores (mean ± SD) were 11.2 ± 2.2 for the Flesch-Kincaid Grade Level Index and 11.2 ± 1.6 for the Coleman-Liau Readability Index. The accuracy and the quality of the websites on kidney and bladder cancers varied. In most websites, there were deficiencies in clarity of aims, presenting symptoms, investigations and treatment options. The readability matched grades 10-11 literacy levels-a level above the public readability level. The study highlights the needs for further improvement of the online information created for public and patients with kidney and bladder cancers.

Genetic Variations in the 3'-untranslated Regions of Genes Involved in the Cell Cycle and Apoptosis Pathways Affect Bladder Cancer Risk

BACKGROUND

Key genes related to cell cycle and apoptosis pathways play critical roles in bladder cancer. Single nucleotide polymorphisms (SNPs) in the 3'-untranslated regions (3'-UTR) of genes may impact microRNA (miRNA)-messenger RNA (mRNA) binding capacity and alter gene expression to contribute to the susceptibility of cancers. However, an association of genetic variations in cell cycle and apoptosis pathways with bladder cancer risk, has not been reported.

MATERIALS AND METHODS

We selected SNPs in the 3'-UTR of cell cycle and apoptosis pathways genes and genotyped them with a case-control study consisting of 578 bladder cancer patients and 1,006 cancer-free subjects. Dual luciferase reporter gene assay was performed to validate the biological function of important SNPs.

RESULTS

We found that 5 SNPs might change the binding ability of miRNA to their target genes, among which PPP3CC rs7431 A>G located in the 3'-untranslated regions with the minimum p-value (p=5.75×10^-4). Analysis revealed that the rs7431 disrupted miR-212 and miR-132 targeting sites. Logistic regression revealed a significantly decreased risk of bladder cancer associated with the PPP3CC rs7431 A>G polymorphism with an odds ratio (OR) of 0.76 [95% confidence interval (CI)=0.66-0.89, p=5.75×10^-4]. Luciferase report assay showed that both miR-212 and miR-132 could lead to significantly increased PPP3CC expression levels in the construct with the G allele compared to the A allele.

CONCLUSION

PPP3CC rs7431 may alter miRNA binding ability of miR-212 and miR-132, and thus decrease bladder cancer risk.

The N-butyl-N-4-hydroxybutyl Nitrosamine Mouse Urinary Bladder Cancer Model

Urinary bladder cancer (UBC) is a common and complex malignancy, with a multifactorial etiology, like environmental factors, such as cigarette smoking, occupational exposure, and genetic factors.UBC exhibits considerable genotypic and phenotypic heterogeneity. Among all UBC lesions, urothelial carcinoma is the most frequently observed histological type. Despite all the developments made in urologic oncology field, therapeutic options remain inadequate. There is urgency for the identification and development of new antineoplastic drugs to replace or improve current protocols and in vivo models have been proven to be essential for this step. There are different animal models of UBC: Spontaneous and experimentally induced models (genetically engineered, transplantable-xenograft and syngeneic animals- and chemically induced models). N-butyl-N(4-hydroxybutil)nitrosamine (BBN) is the most suitable reagent to generate chemically induced in vivo models of UBC and to study bladder carcinogenesis. BBN has proven, over the years, to be very realistic and reliable. It is bladder specific, and induces high tumor incidence.

Differentiation-associated urothelial cytochrome P450 oxidoreductase predicates the xenobiotic-metabolizing activity of "luminal" muscle-invasive bladder cancers

Extra-hepatic metabolism of xenobiotics by epithelial tissues has evolved as a self-defence mechanism but has potential to contribute to the local activation of carcinogens. Bladder epithelium (urothelium) is bathed in excreted urinary toxicants and pro-carcinogens. This study reveals how differentiation affects cytochrome P450 (CYP) activity and the role of NADPH:P450 oxidoreductase (POR). CYP1A1 and CYP1B1 transcripts were inducible in normal human urothelial (NHU) cells maintained in both undifferentiated and functional barrier-forming differentiated states in vitro. However, ethoxyresorufin O-deethylation (EROD) activity, the generation of reactive BaP metabolites and BaP-DNA adducts, were predominantly detected in differentiated NHU cell cultures. This gain-of-function was attributable to the expression of POR, an essential electron donor for all CYPs, which was significantly upregulated as part of urothelial differentiation. Immunohistology of muscle-invasive bladder cancer (MIBC) revealed significant overall suppression of POR expression. Stratification of MIBC biopsies into "luminal" and "basal" groups, based on GATA3 and cytokeratin 5/6 labeling, showed POR over-expression by a subgroup of the differentiated luminal tumors. In bladder cancer cell lines, CYP1-activity was undetectable/low in basal PORlo T24 and SCaBER cells and higher in the luminal POR over-expressing RT4 and RT112 cells than in differentiated NHU cells, indicating that CYP-function is related to differentiation status in bladder cancers. This study establishes POR as a predictive biomarker of metabolic potential. This has implications in bladder carcinogenesis for the hepatic versus local activation of carcinogens and as a functional predictor of the potential for MIBC to respond to prodrug therapies.

A Versatile Assay for Detection of Aberrant DNA Methylation in Bladder Cancer

Urothelial carcinoma of the bladder is one of the most common malignancies in the industrialized world, mainly caused by smoking and occupational exposure to chemicals. The favorable prognosis of early stage bladder cancer underscores the importance of early detection for the treatment of this disease. The high recurrence rate of this malignancy also highlights the need for close post-diagnosis monitoring of bladder cancer patients. As for other malignancies, aberrant DNA methylation has been shown to play a crucial role in the initiation and progression of bladder cancer, and thus holds great promise as a diagnostic and prognostic biological marker. Here, we describe a protocol for a versatile DNA methylation enrichment method, the Methylated CpG Island Recovery Assay (MIRA), which enables analysis of the DNA methylation status in individual genes or across the entire genome. MIRA is based on the ability of the methyl-binding domain (MBD) proteins, the MBD2B/MBD3L1 complex, to specifically bind methylated CpG dinucleotides. This easy-to-perform method can be used to analyze the methylome of bladder cancer or urothelial cells shed in the urine to elucidate the evolution of bladder carcinogenesis and/or identify epigenetic signatures of chemicals known to cause this malignancy.

Association of nineteen polymorphisms from seven DNA repair genes and the risk for bladder cancer in Gansu province of China

Background

Balance of DNA damage and proper repair plays an important role in progression of bladder cancer. Here we aimed to assess the associations of nineteen polymorphisms from seven DNA repair–associated genes (PRAP1, OGG1, APEX1, MUTYH, XRCC1, XRCC2 and XRCC3) with bladder cancer and their interactions in the disease in a Han Chinese population.

Methodology/Principal Findings

A chip-based TaqMan genotyping for the candidate genes was performed on 227 bladder cancer patients and 260 healthy controls. APEX1 rs3136817, MUTYH rs3219493, three SNPs (rs3213356, rs25487 and rs1799782) in XRCC1, and three SNPs (rs1799794, rs861531 and rs861530) in XRCC3 showed significant associations with the risk of bladder cancer. In haplotype analysis, elevated risks of bladder cancer were observed in those with either haplotype GT (OR = 1.56, P = 0.003) of APEX1, or GGGTC (OR = 2.05, P = 0.002) of XRCC1, whereas decreased risks were in individuals with either GCGCC (OR = 0.40, P = 0.001), or GCGTT (OR = 0.60, = 0.005) of XRCC1, or CCC (OR = 0.65, P = 0.004) of MUTYH, or TTTAT (OR = 0.36, P = 0.009) of XRCC3. Interaction analysis showed that the two-loci model (rs1799794 and rs861530) was the best with the maximal testing accuracy of 0.701, and the maximal 100% cross-validation consistency (P = 0.001).

Conclusions

Polymorphisms and haplotypes of DNA repair genes are associated with the risk of bladder cancer, and of which the SNPs (rs1799794 and rs861530) in XRCC3 gene might be two major loci in relation to the susceptibility to bladder cancer in a northwest Chinese population.

Strong associations between chromosomal aberrations in blood lymphocytes and the risk of urothelial and squamous cell carcinoma of the bladder

Chromosomal aberrations (CAs) in blood lymphocytes have been shown to be associated with overall cancer risk and aging. However, their relationship to bladder cancer risk remains to be elucidated. In a case-control study of bladder cancer in Egypt, we examined the relationship between the increased frequency of CAs in blood lymphocytes and bladder cancer risk. High frequency of CAs was significantly associated with an increased risk of bladder cancer [adjusted odds ratios (OR) = 3.90, 95% confidence interval (CI) = 2.65-5.73]. The associations were somewhat stronger in squamous cell carcinomas (SCC, OR = 4.90) than in urothelial carcinomas (UC, OR = 3.62). We also identified chromosome specific CAs for chromosomes 3, 4, 5, 8, 9, 10, 11, 12, 17, 19 that were significantly associated with an increased risk of bladder cancer. We observed particularly strong associations between aberrations of chromosomes 12, 13, 17 and risk of SCC (OR = 7.06, 6.91 and 6.23, respectively).

CONCLUSION

increased frequency of chromosomal aberrations in blood lymphocytes was significantly associated with bladder cancer risk. Overall and chromosome specific aberrations in blood lymphocytes may be a unique set of biomarkers for risk assessments of SCC and UC.

The Diagnostic Value of Nuclear Matrix Proteins in Bladder Cancer in the Aspect of Environmental Risk from Carcinogens

BACKGROUND

The interaction of environmental factors with genetic susceptibility and detoxification level seems to be an important causative factor in bladder cancer (BC). The aim of this study was to look for a BC marker panel which reflects the environmental risk. The nuclear matrix protein 22 (NMP22), bladder cancer-4 (BLCA-4), and total level proteins NMP22 and BLCA-4 (NMBL) in BC patients with genetic predisposition NAT2 (classified as slow acetylators, SA), DNA damage (8-OHdG), and detoxification by isoenzyme GSTπ activity were measured.

MATERIALS AND METHODS

The urine and blood from 91 BC patients and controls were examined, also according to tumor stage (T) and grade (G). The participants completed a questionnaire in order to evaluate environmental risk.

RESULTS

Most patients (75.3%) were previous or actual smokers. The levels of 8-OHdG, NMP22, BLCA-4, NMBL, and GSTπ were significantly higher in BC (p ≤ 0.001). The majority of patients (59.3%) were slow acetylators (SA). The highest BLCA-4/8-OHdG correlation was observed in total BC and SA smokers.

CONCLUSIONS

The total pool of nuclear matrix proteins in the urine (NMBL) has a higher diagnostic value in bladder cancer than single proteins. The particular value of BLCA-4 and GSTπ in the aspect of environmental risk was noted.

George DM, Loffredo CA, Amr S. Nonoccupational exposure to agricultural work and risk of urinary bladder cancer among Egyptian women

This study examined the associations between nonoccupational exposure to agricultural work, through husband or head of household (H/HH) occupation, and urinary bladder cancer risk among Egyptian women. A total of 1,167 women (388 bladder cases and 779 age- and residence-matched, population-based controls) from a multicenter case-control study were included in the analysis. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were estimated using logistic regression. Among married women, those who reported H/HH to be an agricultural worker were at increased risk for bladder cancer as compared to those with H/HH in other occupations, AOR = 1.54, 95% CI [1.09, 2.18]; among unmarried women the risk was not increased, AOR = 0.77, 95% CI [0.45, 1.32]. Nonoccupational exposure to agricultural work, defined as living with an agricultural worker, increased the risk for bladder cancer among married Egyptian women.

Combined Genetic Biomarkers Confer Susceptibility to Risk of Urothelial Bladder Carcinoma in a Saudi Population

We evaluated the associations between seven single nucleotide polymorphisms and susceptibility to urothelial bladder carcinoma (UBC) in a Saudi population. Genomic DNA was taken from buccal cells of 52 patients with UBC and 104 controls for genotyping of GSTT1, GSTM1, rs4646903, rs1048943, TP53 rs1042522, rs1801133, and rs1801394 using PCR and TaqMan® assays. The rs1801133 and rs1801394 variants showed strong associations with UBC (OR = 2.3, P = 0.0002; OR = 2.6, P = 0.0001, resp.). Homozygosity of Pro72 conferred a significant double risk in cases compared with controls (30.8% versus 15.4%), but the homozygote Arg/Arg had no effect on risk. Genotypic combinations of GSTM1/GSTT1, rs4646903/rs1048943, and rs1801133/rs1801394 exhibited significant linkage with the disease (χ² = 10.3, P = 0.006; χ² = 13.9, P = 0.003; and χ² = 20.4, P = 0.0004, resp.). The GSTM1 and rs1042522Arg and rs1801394G variant alleles were more frequent in current smokers with UBC (52.4%, 52.5%, and 64.3%, resp.) than were the corresponding wild-types. Despite some variants having only a slight effect on UBC risk, the interaction effect of combined genetic biomarkers-or even the presence of one copy of a variant allele-is potentially much greater. Perhaps more studies regarding next-generation genetic sequencing and its utility can add to the risk of UBC.

Combined Genetic Biomarkers Confer Susceptibility to Risk of Urothelial Bladder Carcinoma in a Saudi Population

We evaluated the associations between seven single nucleotide polymorphisms and susceptibility to urothelial bladder carcinoma (UBC) in a Saudi population. Genomic DNA was taken from buccal cells of 52 patients with UBC and 104 controls for genotyping of GSTT1, GSTM1, rs4646903, rs1048943, TP53 rs1042522, rs1801133, and rs1801394 using PCR and TaqMan® assays. The rs1801133 and rs1801394 variants showed strong associations with UBC (OR = 2.3, P = 0.0002; OR = 2.6, P = 0.0001, resp.). Homozygosity of Pro72 conferred a significant double risk in cases compared with controls (30.8% versus 15.4%), but the homozygote Arg/Arg had no effect on risk. Genotypic combinations of GSTM1/GSTT1, rs4646903/rs1048943, and rs1801133/rs1801394 exhibited significant linkage with the disease (χ² = 10.3, P = 0.006; χ² = 13.9, P = 0.003; and χ² = 20.4, P = 0.0004, resp.). The GSTM1 and rs1042522Arg and rs1801394G variant alleles were more frequent in current smokers with UBC (52.4%, 52.5%, and 64.3%, resp.) than were the corresponding wild-types. Despite some variants having only a slight effect on UBC risk, the interaction effect of combined genetic biomarkers-or even the presence of one copy of a variant allele-is potentially much greater. Perhaps more studies regarding next-generation genetic sequencing and its utility can add to the risk of UBC.

Investigation of the association between mitochondrial DNA and p53 gene mutations in transitional cell carcinoma of the bladder

Bladder carcinoma is the most common malignancy of the urinary tract. The major aim of the present study is to investigate the association between mitochondrial DNA (mtDNA) and p53 gene mutations in bladder carcinoma. A total of 30 patients with transitional cell carcinoma and 27 controls were recruited for the study. Bladder cancer tissues were obtained by radical cystectomy or transurethral resection. Genomic DNA was extracted from peripheral blood. mtDNA and p53 genes were amplified by polymerase chain reaction and sequenced directly. A total of 37 polymorphisms were identified, among which, 2 mutations were significant in the patient group, and 1 mutation was significant in the control group. Additionally, 5 different moderate positive correlations between mtDNA mutations and 3 different positive correlations between p53 gene and mtDNA mutations were detected. The high incidence of mtDNA and p53 gene mutations in bladder cancer suggests that these genes could be important in carcinogenesis.

Falling bladder cancer incidence from 1990 to 2009 is not producing universal mortality improvements

Objective

The objective of this article is to obtain up-to-date epidemiological statistics of bladder cancer in England.

Methods

We collected incidence from the National Cancer Data Repository (NCDR), survival from the national Cancer Information System (CIS), ethnicity information from the Hospital Episode Statistics (HES), mortality and smoking rates from the Office for National Statistics (ONS).

Results

Incidence of bladder cancer has fallen continuously. Mortality has reduced less, leading to worsening survival. Bladder cancer mainly affects men, the most deprived, and the elderly. The gender gap is decreasing, and the deprivation gap is unchanged. Mortality is unchanged in the youngest, oldest and least deprived females. Mortality has recently increased in the oldest males. The highest incidence and mortality is found in industrial areas. This study is limited by i) its retrospective design using existing databases, allowing identification of associations and statistical differences, but not causation; and ii) very restricted ethnicity data.

onclusion

Reductions in bladder cancer incidence and mortality in England coincide with a decrease in high-risk occupations and public health measures to reduce smoking. Some risk factors in modern living may as yet be unidentified. It remains paramount to ensure equity of access and treatment regardless of gender, age, region and social deprivation to further improve mortality.

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.

Incidental Diagnosis of Bladder Cancer in a 17-year-old Patient

Bladder cancer is the fourth most common type of cancer among males and the ninth most common cause of cancer death. Bladder cancer can occur at any age. This paper reports the incidental diagnosis of bladder cancer in a 17-year-old female patient. Data on bladder cancer at this age are uncommon in the literature.

Integrative Pathway Analysis of Metabolic Signature in Bladder Cancer: A Linkage to The Cancer Genome Atlas Project and Prediction of Survival

Purpose

We used targeted mass spectrometry to study the metabolic fingerprint of urothelial cancer and determine whether the biochemical pathway analysis gene signature would have a predictive value in independent cohorts of patients with bladder cancer.

Materials and Methods

Pathologically evaluated, bladder derived tissues, including benign adjacent tissue from 14 patients and bladder cancer from 46, were analyzed by liquid chromatography based targeted mass spectrometry. Differential metabolites associated with tumor samples in comparison to benign tissue were identified by adjusting the p values for multiple testing at a false discovery rate threshold of 15%. Enrichment of pathways and processes associated with the metabolic signature were determined using the GO (Gene Ontology) Database and MSigDB (Molecular Signature Database). Integration of metabolite alterations with transcriptome data from TCGA (The Cancer Genome Atlas) was done to identify the molecular signature of 30 metabolic genes. Available outcome data from TCGA portal were used to determine the association with survival.

Results

We identified 145 metabolites, of which analysis revealed 31 differential metabolites when comparing benign and tumor tissue samples. Using the KEGG (Kyoto Encyclopedia of Genes and Genomes) Database we identified a total of 174 genes that correlated with the altered metabolic pathways involved. By integrating these genes with the transcriptomic data from the corresponding TCGA data set we identified a metabolic signature consisting of 30 genes. The signature was significant in its prediction of survival in 95 patients with a low signature score vs 282 with a high signature score (p = 0.0458).

Conclusions

Targeted mass spectrometry of bladder cancer is highly sensitive for detecting metabolic alterations. Applying transcriptome data allows for integration into larger data sets and identification of relevant metabolic pathways in bladder cancer progression.

Trends in cancer of the urinary bladder and urinary tract in elderly in Denmark, 2008-2012

BACKGROUND

The aim of this study was to examine the trends in incidence, mortality, survival, and prevalence of cancers of the urinary bladder and urinary tract in Denmark from 1980 to 2012 with particular focus on elderly patients over age 70 years.

DESIGN

Cancer of the urinary bladder and urinary tract was defined as ICD-10 codes C67.9, D09.0, D41.4. Data were derived from the NORDCAN database with comparable data on cancer incidence, mortality, prevalence and relative survival in the Nordic countries, where the Danish data were delivered from the Danish Cancer Registry and the Danish Cause of Death Registry.

RESULTS

The average annual number of bladder cancers increased from 1478 to 1810 (22%) from 1980 to 2012, with close to 60% occurring in the elderly population. The incidence rates were 7-10 times higher in persons aged 70 years or more compared with younger persons. Mortality rates were decreasing with time in all age groups but 90+-year-old men. The one- and five-year relative survival improved significantly with time for all age groups both in men and women. The prevalence increased two times from 6014 in 1980 to 12 359 in 2012 among men and from 1974 to 4454 among women. There was a relatively higher proportional increase in prevalence among elderly men compared to younger patients.

CONCLUSION

More prospective data are needed, preferably as randomized clinical trials, for determining the influence of age on the decisions of the surgical approach as well as chemo/radiotherapy for the elderly patients with urothelial cancers compared to younger patients.

Arsenic in Drinking Water, Transition Cell Cancer and Chronic Cystitis in Rural Bangladesh

In earlier analyses, we demonstrated dose-response relationships between renal and lung cancer and local arsenic concentrations in wells used by Bangladeshi villagers. We used the same case-referent approach to examine the relation of arsenic to biopsy confirmed transition cell cancer (TCC) of the ureter, bladder or urethra in these villagers. As the International Agency for Research on Cancer (IARC) has conclude that arsenic in drinking water causes bladder cancer, we expected to find higher risk with increasing arsenic concentration. We used histology/cytology results from biopsies carried out at a single clinic in Dhaka, Bangladesh from January 2008 to October 2011. We classified these into four groups, TCC (n = 1466), other malignancies (n = 145), chronic cystitis (CC) (n = 844) and other benign (n = 194). Arsenic concentration was estimated from British Geological Survey reports. Odds ratios were calculated by multilevel logistic regression adjusted for confounding and allowing for geographic clustering. We found no consistent trend for TCC with increasing arsenic concentration but the likelihood of a patient with benign disease having CC was significantly increased at arsenic concentrations >100 µg/L. We conclude that the expected relationship of TCC to arsenic was masked by over-matching that resulted from the previously unreported relationship between arsenic and CC. We hypothesize that CC may be a precursor of TCC in high arsenic areas.

Gender and Bladder Cancer: A Collaborative Review of Etiology, Biology, and Outcomes

CONTEXT

The incidence of bladder cancer is three to four times greater in men than in women. However, women are diagnosed with more advanced disease at presentation and have less favorable outcomes after treatment.

OBJECTIVE

To review the literature on potential biologic mechanisms underlying differential gender risk for bladder cancer, and evidence regarding gender disparities in bladder cancer presentation, management, and outcomes.

EVIDENCE ACQUISITION

A literature search of English-language publications that included an analysis of the association of gender with bladder cancer was performed using Pubmed. Ninety-seven articles were selected for analysis with the consensus of all authors.

EVIDENCE SYNTHESIS

It has been shown that the gender difference in bladder cancer incidence is independent of differences in exposure risk, including smoking status. Potential molecular mechanisms include disparate metabolism of carcinogens by hepatic enzymes between men and women, resulting in differential exposure of the urothelium to carcinogens. In addition, the activity of the sex steroid hormone pathway may play a role in bladder cancer development, with demonstration that both androgens and estrogens have biologic effects in bladder cancer in vitro and in vivo. Importantly, gender differences exist in the timeliness and completeness of hematuria evaluation, with women experiencing a significantly greater delay in urologic referral and undergoing guideline-concordant imaging less frequently. Correspondingly, women have more advanced tumors at the time of bladder cancer diagnosis. Interestingly, higher cancer-specific mortality has been noted among women even after adjusting for tumor stage and treatment modality.

CONCLUSIONS

Numerous potential biologic and epidemiologic factors probably underlie the gender differences observed for bladder cancer incidence, stage at diagnosis, and outcomes. Continued evaluation to define clinical applications for manipulation of the sex steroid pathway and to improve the standardization of hematuria evaluation in women may improve future patient outcomes and reduce these disparities.

PATIENT SUMMARY

We describe the scientific basis and clinical evidence to explain the greater incidence of bladder cancer in men and the adverse presentation and outcomes for this disease in women. We identify goals for improving patient survival and reducing gender disparities in bladder cancer.

Genetic variation in PSCA is associated with bladder cancer susceptibility in a Korean population

BACKGROUND

Genetic factors play important roles in the pathogenesis of human cancer. A recent genome wide association study (GWAS) identified an association between the rs2294008 polymorphism of the prostate stem cell antigen (PSCA) gene and bladder cancer risk in Caucasians. The aim of this study was to determine whether the rs2294008 polymorphism is similarly associated with bladder cancer susceptibility in a Korean population.

MATERIALS AND METHODS

We conducted a case-control study of 411 bladder cancer patients and 1,700 controls.

RESULTS

The frequencies of the CC, CT, and TT genotypes of the rs2294008 polymorphism were 16.9, 54.0, and 28.8% in bladder cancer patients and 24.4, 48.1, and 27.5% in controls, respectively. We found that the combined CT/TT genotypes were associated with a significantly increased risk of bladder cancer (OR CT/TT=1.58, 95% CI=1.15-2.17), compared with the CC genotype. Smoking habits, tumor grade and tumor stage did not modify the association between rs2294008 and the risk of bladder cancer.

CONCLUSIONS

Our study showed that the rs2294008 polymorphism in the PSCA gene is associated with the risk of bladder cancer in a Korean population, providing evidence that it may contribute to bladder carcinogenesis regardless of ethnicity.

Involvement of epigenetics and EMT-related miRNA in arsenic-induced neoplastic transformation and their potential clinical use

Exposure to toxicants leads to cumulative molecular changes that overtime increase a subject's risk of developing urothelial carcinoma. To assess the impact of arsenic exposure at a time progressive manner, we developed and characterized a cell culture model and tested a panel of miRNAs in urine samples from arsenic-exposed subjects, urothelial carcinoma patients, and controls. To prepare an in vitro model, we chronically exposed an immortalized normal human bladder cell line (HUC1) to arsenic. Growth of the HUC1 cells was increased in a time-dependent manner after arsenic treatment and cellular morphology was changed. In a soft agar assay, colonies were observed only in arsenic-treated cells, and the number of colonies gradually increased with longer periods of treatment. Similarly, invaded cells in an invasion assay were observed only in arsenic-treated cells. Withdrawal of arsenic treatment for 2.5 months did not reverse the tumorigenic properties of arsenic-treated cells. Western blot analysis demonstrated decreased PTEN and increased AKT and mTOR in arsenic-treated HUC1 cells. Levels of miR-200a, miR-200b, and miR-200c were downregulated in arsenic-exposed HUC1 cells by quantitative RT-PCR. Furthermore, in human urine, miR-200c and miR-205 were inversely associated with arsenic exposure (P = 0.005 and 0.009, respectively). Expression of miR-205 discriminated cancer cases from controls with high sensitivity and specificity (AUC = 0.845). Our study suggests that exposure to arsenic rapidly induces a multifaceted dedifferentiation program and miR-205 has potential to be used as a marker of arsenic exposure as well as a maker of early urothelial carcinoma detection.

Pesticides, gene polymorphisms, and bladder cancer among Egyptian agricultural workers

This study examined the associations between pesticide exposure, genetic polymorphisms for

NAD(P)H

quinone oxidoreductase I (NQO1) and superoxide dismutase 2 (SOD2), and urinary bladder cancer risk among male agricultural workers in Egypt. Logistic regression was used to analyze data from a multicenter case-control study and estimate adjusted odds ratio (OR) and 95% confidence interval (CI). Exposure to pesticides was associated with increased bladder cancer risk (odds ratio (95% confidence interval): 1.68 (1.23-2.29)) in a dose-dependent manner. The association was slightly stronger for urothelial (1.79 (1.25-2.56)) than for squamous cell (1.55 (1.03-2.31)), and among participants with combined genotypes for low NQO1 and high SOD2 (2.14 (1.19-3.85)) activities as compared with those with high NQO1 and low SOD2 genotypes (1.53 (0.73-3.25)). In conclusion, among male agricultural workers in Egypt, pesticide exposure is associated with bladder cancer risk and possibly modulated by genetic polymorphism.