Urinary bladder cancer risk factors: a Lebanese case- control study

Uncovering the epidemiology of bladder cancer in the Arab world: A review of risk factors, molecular mechanisms, and clinical features

Objective

Bladder cancer (BC) is a significant public health concern in the Middle East and North Africa, but the epidemiology and clinicopathology of the disease and contributors to high mortality in this region remain poorly understood. The aim of this systematic review was to investigate the epidemiological features of BC in the Arab world and compare them to those in Western countries in order to improve the management of this disease.

Methods

An extensive electronic search of the PubMed/PMC and Cochrane Library databases was conducted to identify all articles published until May 2022, following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. A total of 95 articles were included in the final analysis after title, abstract, and full-text screening, with additional data obtained from the GLOBOCAN and WHO 2020 databases.

Results

Most of the included articles were case-control studies examining the risk factors and molecular mechanisms of BC. These studies originated from 10 different countries, with Egypt being the most active contributor. While BC in the Arab world shares some common risk factors with Western countries, such as smoking and occupational exposure, it also exhibits unique features related to schistosomiasis. The high mortality rates in this region are alarming and can be attributed to various factors, including the prevalence of smoking, the impact of schistosomiasis, a combination of genetic and socioeconomic factors, treatment shortages, and limited access to care or inadequate assessment of the quality of care.

Conclusion

Despite the relatively low incidence of BC in Arab countries, the mortality rates are among the highest worldwide. BC tends to be more aggressive in the Arab world, making it essential to implement strategies to address this burden.

Pharmacogenomics in Lebanon: current status, challenges and opportunities

Pharmacogenomics (PGx) research and applications are of utmost relevance in Lebanon considering its population genetic diversity. Moreover, as a country with regional leadership in medicine and higher education, Lebanon holds a strong potential in contributing to PGx research and clinical implementation. In this manuscript, we first review and evaluate the available PGx research conducted in Lebanon, then describe the current status of PGx practice in Lebanon while reflecting on the local and regional challenges, and highlighting areas for action, and opportunities to move forward. We specifically expand on the status of PGx at the American University of Beirut Faculty of Medicine and Medical Center as a case study and guide for the further development of local and regional comprehensive PGx research, teaching, and clinical implementation programs. We also delve into the status of PGx knowledge and education, and prospects for further advancement such as with online courses and certificates.

Polymorphisms in drug-metabolizing genes and urinary bladder cancer susceptibility and prognosis: Possible impacts and future management

Epidemiological studies have shown the association of genetic variants with risks of occupational and environmentally induced cancers, including bladder (BC). The current review summarizes the effects of variants in genes encoding phase I and II enzymes in well-designed studies to highlight their contribution to BC susceptibility and prognosis. Polymorphisms in genes codifying drug-metabolizing proteins are of particular interest because of their involvement in the metabolism of exogenous genotoxic compounds, such as tobacco and agrochemicals. The prognosis between muscle-invasive and non-muscle-invasive diseases is very different, and it is difficult to predict which will progress worse. Web of Science, PubMed, and Medline were searched to identify studies published between January 1, 2010, and February 2023. We included 73 eligible studies, more than 300 polymorphisms, and 46 genes/loci. The most studied candidate genes/loci of phase I metabolism were CYP1B1, CYP1A1, CYP1A2, CYP3A4, CYP2D6, CYP2A6, CYP3E1, and ALDH2, and those in phase II were GSTM1, GSTT1, NAT2, GSTP1, GSTA1, GSTO1, and UGT1A1. We used the 46 genes to construct a network of proteins and to evaluate their biological functions based on the Reactome and KEGG databases. Lastly, we assessed their expression in different tissues, including normal bladder and BC samples. The drug-metabolizing pathway plays a relevant role in BC, and our review discusses a list of genes that could provide clues for further exploration of susceptibility and prognostic biomarkers.

Establishment and validation of nomograms to predict the overall survival and cancer-specific survival for non-metastatic bladder cancer patients: A large population-based cohort study and external validation

This study aimed to develop nomograms to accurately predict the overall survival (OS) and cancer-specific survival (CSS) of non-metastatic bladder cancer (BC) patients. Clinicopathological information of 260,412 non-metastatic BC patients was downloaded from the Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2020. LASSO method and Cox proportional hazard regression analysis were utilized to discover the independent risk factors, which were used to develop nomograms. The accuracy and discrimination of models were tested by the consistency index (C-index), the area under the subject operating characteristic curve (AUC) and the calibration curve. Decision curve analysis (DCA) was used to test the clinical value of nomograms compared with the TNM staging system. Nomograms predicting OS and CSS were constructed after identifying independent prognostic factors. The C-index of the training, internal validation and external validation cohort for OS was 0.722 (95%CI: 0.720-0.724), 0.723 (95%CI: 0.721-0.725) and 0.744 (95%CI: 0.677-0.811). The C-index of the training, internal validation and external validation cohort for CSS was 0.794 (95%CI: 0.792-0.796), 0.793 (95%CI: 0.789-0.797) and 0.879 (95%CI: 0.814-0.944). The AUC and the calibration curves showed good accuracy and discriminability. The DCA showed favorable clinical potential value of nomograms. Kaplan-Meier curve and log-rank test uncovered statistically significance survival difference between high- and low-risk groups. We developed nomograms to predict OS and CSS for non-metastatic BC patients. The models have been internally and externally validated with accuracy and discrimination and can assist clinicians to make better clinical decisions.

Evaluation of the Effects of Opium on the Expression of SOX2 and OCT4 in Wistar Rat Bladder

BACKGROUND

Bladder cancer is a malignancy greatly affected by behavioral habits. The aim of this study was to examine the effect of opium on changes in the expression of OCT4 and SOX2 in the bladder tissue of rats.

METHOD

Thirty six rats were divided into six groups: 24 rats in the addicted group received morphine and opium for 4 months with 12 rats in the control group. Blood testing was done for the evaluation of CBC, MDA, and TAC. The bladder tissue was removed and checked by histopathological examination. All total RNA was extracted, then cDNAs were synthesized and the OCT4 and SOX2 gene expressions were evaluated by Real-time PCR.

RESULTS

The OCT4 mRNA expression level in the opium group of rats was significantly increased compared to the control group (13.5 and 6.8 fold in males and females respectively). Also, in the morphine group, similar augmentation was detected (3.8 and 6.7 fold in males and females respectively). The SOX2 mRNA over-expression level was seen in the morphine group of both genders as compared to the control group (3.7 and 4.2 fold in male and female respectively) but in the opium group, enhancement of mRNA level was seen only in males (6.6 fold). Opium increases both OCT4 and SOX2 expression more than morphine in male rats, but in female rats, SOX2 is increased more by morphine.

CONCLUSION

Over expression of OCT4 and SOX2 was observed in rats treated with opium and morphine. Increased OCT4 and SOX2 expression was seen in opium-treated male rats, but in female rats, SOX2 was increased more by morphine.

Is there a promoting role for artificial sweeteners in the evolution of bladder cancer? A meta-analysis of current literature

INTRODUCTION

Urinary bladder cancer is a frequent neoplasia in the urogenital system. Ageing and smoking are the two main risk factors, however, some chemical agents such as artificial sweeteners could act as initiators or promoters.

EVIDENCE ACQUISITION

After identifying trends in scientific literature, we conducted a wide search in PubMed database and a meta-analysis was performed on extracted data to determine the role of artificial sweeteners in the development of urinary bladder cancer.

EVIDENCE SYNTHESIS

Twenty-one full reports were enrolled from screening of PubMed database into final analysis involving 116,568 subjects in comparisons. Overall, 13,682 and 102,886 cases were identified for bladder cancer patients and healthy controls, respectively. Among artificial sweetener users, 12.5% was the incidence of bladder cancer. In the control group, 11.2% of cases suffered from urothelial carcinoma of the bladder. About 40.7% of the patients suffering from urinary neoplasms and 37.8% of the healthy cases were artificial sweetener users, respectively. There were only minor differences in overall descriptive data. The incidence of urinary bladder cancer among artificial sweetener users and control cases showed no risk difference (RD: 0.00, CI: -0.06 to 0.06). The frequency of artificial sweetener use among patients suffering from urinary bladder neoplasms and healthy subjects was compared which showed equal occurrences (OR: 0.96, CI: 0.79 to 1.17).

CONCLUSIONS

According to our results, the carcinogenic risk of artificial sweeteners is not proven. Saccharin should not be kept as a promoter in urothelial malignant transformation.

Genetic Polymorphisms Involved in Bladder Cancer: A Global Review

Bladder cancer (BC) has been associated with genetic susceptibility. Single peptide polymorphisms (SNPs) can modulate BC susceptibility. A literature search was performed covering the period between January 2000 and October 2020. Overall, 334 articles were selected, reporting 455 SNPs located in 244 genes. The selected 455 SNPs were further investigated. All SNPs that were associated with smoking and environmental exposure were excluded from this study. A total of 197 genes and 343 SNPs were found to be associated with BC, among which 177 genes and 291 SNPs had congruent results across all available studies. These genes and SNPs were classified into eight different categories according to their function.

Non-sugar sweeteners and cancer: Toxicological and epidemiological evidence

Several toxicological and epidemiological studies were published during the last five decades on non-sugar sweeteners (NSS) and cancer. Despite the large amount of research, the issue still continues to be of interest. In this review, we provided a comprehensive quantitative review of the toxicological and epidemiological evidence on the possible relation between NSS and cancer. The toxicological section includes the evaluation of genotoxicity and carcinogenicity data for acesulfame K, advantame, aspartame, cyclamates, saccharin, steviol glycosides and sucralose. The epidemiological section includes the results of a systematic search of cohort and case-control studies. The majority of the 22 cohort studies and 46 case-control studies showed no associations. Some risks for bladder, pancreas and hematopoietic cancers found in a few studies were not confirmed in other studies. Based on the review of both the experimental data on genotoxicity or carcinogenicity of the specific NSS evaluated, and the epidemiological studies it can be concluded that there is no evidence of cancer risk associated to NSS consumption.

Development and Validation of Nomograms Predicting the 5- and 8-Year Overall and Cancer-Specific Survival of Bladder Cancer Patients Based on SEER Program

BACKGROUND

Bladder cancer is often prone to recurrence and metastasis. We sought to construct nomogram models to predict the overall survival (OS) and cancer-specific survival (CSS) of bladder cancer patients.

METHODS

A reliable random split-sample approach was used to divide patients into two groups: modeling and validation cohorts. Uni-variate and multivariate survival analyses were used to obtain the independent prognostic risk factors based on the modeling cohort. A nomogram was constructed using the R package, "rms". Harrell's concordance index (C-index), calibration curves and receiver operating characteristic (ROC) curves were applied to evaluate the discrimination, sensitivity and specificity of the nomograms using the R packages "hmisc", "rms" and "timeROC". A decision curve analysis (DCA) was used to evaluate the clinical value of the nomograms via R package "stdca.R".

RESULTS

10,478 and 10,379 patients were assigned into nomogram modeling and validation cohorts, respectively (split ratio ≈ 1:1). For OS and CSS, the C-index values for internal validation were 0.738 and 0.780, respectively, and the C-index values for external validation were 0.739 and 0.784, respectively. The area under the ROC curve (AUC) values for 5- and 8-year OS and CSS were all greater than 0.7. The calibration curves show that the predicted probability values of 5- and 8-year OS and CSS are close to the actual OS and CSS. The decision curve analysis revealed that the two nomograms have a positive clinical benefit.

CONCLUSION

We successfully constructed two nomograms to forecast OS and CSS for bladder cancer patients. This information can help clinicians conduct prognostic evaluations in an individualized manner and tailor personalized treatment plans.

Exploring the casual association between coffee intake and bladder cancer risk using Mendelian Randomization

Objective: Several observational studies have suggested that coffee consumption is associated with a lower risk of bladder cancer. However, observational studies are susceptible to confounding factors and reverse causality. We used a two-sample Mendelian randomization (MR) method to assess the causal nature of this association. Methods: At the genome-wide significance level (p < 5 × 10^-8), 12 single nucleotide polymorphisms (SNPs) strongly associated with coffee consumption were used as instrumental variables (IVs). Summary-level data on genetic variation in bladder cancer were obtained from the United Kingdom biobank (420,838 samples) and FinnGen consortium (175,121 samples). Multiple MR methods were used. Heterogeneity and horizontal pleiotropy were detected using Cochran's Q test and MR-Egger. Results: Twelve SNPs were included in the primary analysis. After excluding 8 SNPs with potential secondary phenotypes, the remaining 4 SNPs were included in the sensitivity analysis. In all analyses, Cochran's Q statistic indicated that there was no heterogeneity among SNPs, and the MR-Egger analysis did not reveal the existence of horizontal pleiotropy (p > 0.05). In the United Kingdom Biobank, the odds ratio (OR) for bladder cancer was 1.022 (95% confidence interval (CI), 0.679-1.537) for per 50% increase in coffee consumption. Consistent results were obtained in the FinnGen consortium (OR = 0.890, 95% CI, 0.467-1.697). Sensitivity analysis showed consistent results with primary analysis. Conclusion This study does not support a causal association between habitual coffee consumption and bladder cancer risk.

Waterpipe Smoking among Bladder Cancer Patients: A Cross-Sectional Study of Lebanese and Jordanian Populations

Background

Bladder cancer (BC) is the second most reported cancer in Lebanon and the fifth in Jordan. Its risk factors are mainly smoking and occupational exposure to aromatic amines. In these countries where smoking and bladder cancer are highly prevalent, the role of waterpipe smoking (WPS) in bladder cancer is less investigated. We aim to compare two sets of patients between Lebanon and Jordan, focusing on their smoking habits, WP use, occupational exposure, and the grade/invasiveness of their bladder cancer.

Methods

This is a cross-sectional study that compares the smoking culture between two sets of populations with bladder cancer, from two different countries. We recruited 274 bladder cancer patients over the 18 years of age at the American University of Beirut Medical Center (AUBMC), and 158 bladder cancer patients over the age of 18 years at the King Hussein Cancer Center (KHCC).

Results

7.7% of Lebanese patients had significantly more positive family history of bladder cancer compared to 13.9% of Jordanian patients (p = 0.045). Another significant finding is that the majority of Lebanese patients 70.7% reported being frequently exposed to secondhand smoking, mainly cigarettes, versus only 48.6% of Jordanian patients (p < 0.001). The increasing smoking trend among Lebanese females is remarkably the highest in the region, which contributed to the overall increase in smoking rates in the country. 17.1% of the Lebanese smoking patients are mainly but not exclusively WP smokers of which 6.3% are daily WP smokers, similarly 17.1% of the Jordanian patients of which 3.2% are daily WP smokers. There were 71.5% of Lebanese patients who had a noninvasive BC versus 40% of Jordanian patients (p < 0.001), and more than one-third reported an occupational exposure to one of the risk factors of BC in both groups.

Conclusions

Bladder cancer incidence is on the rise in both Jordan and Lebanon along with different smoking types. It is necessary to impose prevention policies to prevent and control the high smoking prevalence. Bladder cancer invasiveness is higher in Jordan compared to universal data.

Slow N-acetylation as a possible contributor to bladder carcinogenesis

Bladder cancer (BCa) is an exophytic tumor that presents as either noninvasive confined to the mucosa (NMIBC) or invading the detrusor muscle (MIBC), and was recently further subgrouped into molecular subtypes. Arylamines, major BCa environmental and occupational risk factors, are mainly metabolized by the genetically polymorphic N-acetyltransferases 1, NAT1 and NAT2. In this study, we investigated the association between N-acetyltransferases genetic polymorphism and key MIBC and NMIBC tumor biomarkers and subtypes. A cohort of 250 males with histologically confirmed urothelial BCa was identified. Tumors were genotyped for NAT1 and NAT2 using real-time polymerase chain reaction (PCR), and characterized for mutations in TP53, RB1, and FGFR3 by PCR-restriction fragment length polymorphism. Pathology data and patients' smoking status were obtained from medical records. Pearson χ² and Fisher exact tests were used to check for associations and interactions. Results show that NAT1 G⁵⁶⁰ A polymorphism is significantly associated with higher muscle-invasiveness (MIBC vs NMIBC; P = .001), higher tumor grade (high grade vs low grade; P = .011), and higher FGFR3 mutation frequency within the MIBC subgroup (P = .042; .027). NAT2 G⁸⁵⁷ A polymorphism is also found to be significantly associated with higher muscle-invasiveness (MIBC vs NMIBC; P = .041). Our results indicate that slow N-acetylation is a contributor to bladder carcinogenesis and muscle-invasiveness. These findings highlight NAT1 as a biomarker candidate in BCa and a potential target for drug development.

Coffee consumption and risk of bladder cancer: a pooled analysis of 501,604 participants from 12 cohort studies in the BLadder Cancer Epidemiology and Nutritional Determinants (BLEND) international study

Recent epidemiological studies have shown varying associations between coffee consumption and bladder cancer (BC). This research aims to elucidate the association between coffee consumption and BC risk by bringing together worldwide cohort studies on this topic. Coffee consumption in relation to BC risk was examined by pooling individual data from 12 cohort studies, comprising of 2601 cases out of 501,604 participants. Pooled multivariate hazard ratios (HRs), with corresponding 95% confidence intervals (CIs), were obtained using multilevel Weibull regression models. Furthermore, dose-response relationships were examined using generalized least squares regression models. The association between coffee consumption and BC risk showed interaction with sex (P-interaction < 0.001) and smoking (P-interaction = 0.001). Therefore, analyses were stratified by sex and smoking. After adjustment for potential confounders, an increased BC risk was shown for high (> 500 ml/day, equivalent to > 4 cups/day) coffee consumption compared to never consumers among male smokers (current smokers: HR = 1.75, 95% CI 1.27-2.42, P-trend = 0.002; former smokers: HR = 1.44, 95% CI 1.12-1.85, P-trend = 0.001). In addition, dose-response analyses, in male smokers also showed an increased BC risk for coffee consumption of more than 500 ml/day (4 cups/day), with the risk of one cup (125 ml) increment as 1.07 (95% CI 1.06-1.08). This research suggests that positive associations between coffee consumption and BC among male smokers but not never smokers and females. The inconsistent results between sexes and the absence of an association in never smokers indicate that the associations found among male smokers is unlikely to be causal and is possibly caused by residual confounding of smoking.

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.

Distribution and Role of N-acetyltransferase 2 Genetic Polymorphisms in Bladder Cancer Risk in a Lebanese Population

Background:

In Lebanon, bladder cancer (BC) has an unusually high prevalence. Individuals who are exposed to aromatic amines from smoking or certain occupations and carrying the slow N-acetyl transferase 2 (NAT2) acetylator’ phenotype may be at a higher risk.

Methods:

Data and DNA from 115 Lebanese BC cases and 306 controls were examined. Ten NAT2 single nucleotide polymorphisms were genotyped, seven of which were then included in haplotype and phenotype analysis.

Results:

BC patients were more likely to be males (87.8% vs. 54.9%) and current smokers (60.9% vs. 26.5%) when compared to controls. In both groups, most participants had the slow NAT2 acetylator phenotype (66.1% of BC cases vs 62.7% of controls; P=0.302) with the NAT2*5B and *6A haplotypes being the most common. The odds ratio (95%CI) of having BC among slow NAT2 acetylators was 1.157 (0.738-1.815) and remained non-significant after adjustment [1.097 (0.666-1.806)]. Sensitivity analysis with a subgroup of 113 cases and 84 controls for which occupational history was available revealed a statistically significant association between slow NAT2 acetylators and BC in females only. The sample size was however very small and the CI quite wide.

Conclusions:

This is the first study to evaluate the distribution of NAT2 haplotypes and their potential role in BC in a Lebanese population. The absence of any significant association may be due to the relatively small sample size, the unavailability of matching by gender, and the lack of evaluation of genetic interactions with extent of active and passive smoking, exposure to environmental pollutants, diet, and other genes. The potential association limited to females needs further evaluation.

Health outcomes of non-nutritive sweeteners: analysis of the research landscape

BACKGROUND

Food products containing non-nutritive sweeteners (NNSs) instead of sugar have become increasingly popular in the last decades. Their appeal is obviously related to their calorie-free sweet taste. However, with the dramatic increase in their consumption, it is reasonable and timely to evaluate their potential health benefits and, more importantly, potential adverse effects. The main aim of this scoping review was to map the evidence about health outcomes possibly associated with regular NNS consumption by examining the extent, range, and nature of research activity in this area.

METHODS

We systematically searched Ovid MEDLINE, EMBASE and the Cochrane CENTRAL databases for studies on NNSs (artificial sweeteners or natural, non-caloric sweeteners, either used individually or in combination) using text terms with appropriate truncation and relevant indexing terms. All human studies investigating any health outcomes of a NNS intervention or exposure were eligible for inclusion. No studies were excluded based on language, study design or methodological quality. Data for each health outcome were summarized in tabular form and were discussed narratively.

RESULTS

Finally, we included 372 studies in our scoping review, comprising 15 systematic reviews, 155 randomized controlled trials (RCTs), 23 non-randomized controlled trials, 57 cohort studies, 52 case-control studies, 28 cross sectional studies and 42 case series/case reports. In healthy subjects, appetite and short term food intake, risk of cancer, risk of diabetes, risk of dental caries, weight gain and risk of obesity are the most investigated health outcomes. Overall there is no conclusive evidence for beneficial and harmful effects on those outcomes. Numerous health outcomes including headaches, depression, behavioral and cognitive effects, neurological effects, risk of preterm delivery, cardiovascular effects or risk of chronic kidney disease were investigated in fewer studies and further research is needed. In subjects with diabetes and hypertension, the evidence regarding health outcomes of NNS use is also inconsistent.

CONCLUSIONS

This scoping review identifies the needs for future research to address the numerous evidence gaps related to health effects of NNSs use.It also specifies the research questions and areas where a systematic review with meta-analyses is required for the proper evaluation of health outcomes associated to regular NNSs consumption.

Opium and bladder cancer: A systematic review and meta-analysis of the odds ratios for opium use and the risk of bladder cancer

Objective

The association between opium use and bladder cancer has been investigated in many studies, with varying reporting results reported. This study aims to estimate the total odds ratio for the association between bladder cancer and opium consumption using meta-analysis.

Methods

The study was designed according to PRISMA guidelines. Two independent researchers searched for the relevant studies using PubMed, Web of Science, Scopus, OVID, Embase, and Google Scholar. After systematic screening of the studies identified during the first step, Cochrane risk of bias tool was determined for the selected studies. The case-control and the cohort studies were investigated to assess risk of bladder cancer due to opium use. In addition, the cross-sectional studies were analysed separately to assess frequency of opium consumption. These estimates were combined using the inverse variance method. Fixed or random effect models were applied to combine the point odds ratios. The heterogeneity between the primary results was assessed using the Cochran test and I-square index. The suspected factors for heterogeneity were investigated using meta-regression models. An Egger test was conducted to identify any probable publication bias. Forest plots illustrated the point and pooled estimates. All analyses were performed using Stata version 14 software and RevMan version 5.3.

Results

We included 17 primary studies (11 case-control, one cohort and five cross-sectional) in the final meta-analysis. The total odds ratios (95% confidence intervals) for developing bladder cancer by opium use alone, and concurrent use of opium and cigarettes were estimated as 3.85 (3.05–4.87) and 5.7 (1.9–16.3) respectively. The odds ratio (95% confidence interval) for opium use with or without cigarette smoking was estimated as 5.3 (3.6–7.7).

Conclusion

This meta-analysis showed that opium use similar to cigarette smoking and maybe with similar mechanisms can be a risk factor for bladder cancer. It is therefore expected to be a risk factor for other cancers.

Proportion of cancer in a Middle eastern country attributable to established risk factors

Background

Providing an estimate of the percentage of cancer in Lebanon by 2018 that is due to the exposure to risk factors in 2008. Factors include: smoking, body mass index (BMI), physical inactivity, dietary factors, alcohol consumption, infections, and air pollution in adults.

Method

Population Attributable Fraction (PAF) was calculated using the proportion of the population exposed and relative risks for each risk factor from meta-analyses. The PAF estimates the proportion of cases in which exposure may have played a causal role.

Results

Smoking caused most cancer cases, and it will further add a total of 1800 new cases by 2018. Among many other cancers, lung cancer had the largest proportion attributable of around 75%. BMI is expected to increase colorectal, liver and gastric cardia carcinoma specifically in males. High physical activity has a an average of 15% protection rate on cancer on colorectal cancer. Minimal adherence to Mediterranean diet will affect gastric cancer incidence by 7%. Cases of oropharyngeal and esophageal cancer will be the result of alcohol consumption mainly in males. H.Pylori infection is expected to result in half of the gastric cases by 2018. The high exposure to air pollution is expected to contribute by 13% to lung cancer cases in 2018.

Conclusion

The highest benefits can be achieved by controlling tobacco smoking. Interrelated and small changes in weight, physical activity and healthy diet with limited alcohol consumption can protect against several GI cancers in the long run. These results can be used to determine public health interventions that target important risk factors in the general population.

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.

Bladder Cancer Screening in Lebanese Population: There is Nothing more Unequal than the Equal Treatment of Unequal People

Bladder cancer screening has been perplexing the uro-oncological community for the last decade. In this commentary, we ruminate on the feasibility of bladder cancer screening in our population based on epidemiological proponents.

Combined use of Epithelial Membrane Antigen and Nuclear Matrix Protein 52 as Sensitive Biomarkers for Detection of Bladder Cancer

Background

The advent of noninvasive urine-based markers as well as other novel modalities has yielded improved diagnostic accuracy. However, the new markers failed to reach higher sensitivity and specificity. We therefore evaluated the potential role of epithelial membrane antigen (EMA) and nuclear matrix protein 52 (NMP-52) singly and combined as noninvasive biomarkers for the detection of bladder cancer (BC).

Methods

A total of 160 individuals including 66 patients with BC, 54 patients with benign urologic disorders and 40 healthy volunteers were investigated. Urinary EMA at 130 kDa and NMP at 52 kDa were identified, purified and quantified by Western blot, electroelution and enzyme-linked immunosorbent assay (ELISA). The diagnostic performance of each biomarker and their combination were compared using area under receiver operating characteristic curves (AUC).

Results

Mean urinary EMA, 2.42 µg/mL, and NMP-52, 17.85 µg/mL, were significantly elevated in patients with BC compared to controls, 1.18 and 3.44 µg/mL, respectively (p<0.0001). The combined use of these markers yielded values which were increased 4.4- and 13.7-fold in the benign and malignant disease groups, respectively, with respect to the normal group. The values of EMA and NMP-52 were significantly higher in patients with higher-grade tumors than those with lower-grade tumors (p<0.0001). Moreover, this combination could predict all BC stages and grades with 0.91 AUC, 94% sensitivity and 80% specificity.

Conclusions

EMA and NMP-52 in combination could be promising noninvasive biomarkers for BC detection.

A diversity of cancer incidence and mortality in West Asian populations

BACKGROUND

Western Asia comprises a large proportion of the world population with different ethnicities and religions inhabiting areas of diverse geographic features. The countries of this region have experienced rapid economic growth over the latter half of the 20th century, which continues to this day, resulting in major changes in lifestyle of the population.

OBJECTIVES

The aim of this study was to compare the incidence and mortality of cancer in West Asia using the estimates reported by the International Agency for Research on Cancer (IARC) in Globocan-2012.

METHODS

Countries with high-quality data or national data (based on the definition of the Globocan-2012) were included in the analysis. These included Bahrain, Iran, Jordan, Kuwait, Lebanon, Oman, Qatar, Saudi Arabia, and Turkey. We also found high-quality cancer data from regional cancer registries in 3 Iranian and 3 Turkish provinces. Data on cancer incidence and mortality were collected and described in tables and graphs. Spearman's correlation test was used to assess the correlation between geographic coordinates and the incidence age-standardized rate (ASR; per 100,000 person-years) of cancers.

FINDINGS

Nine countries and 6 regional registries were included. Cancers of the lung (ASR, 33.3), prostate (24.9), bladder (19.1), stomach (16.5), and colorectal (15.9) were the most common malignancies in men. The most common cancers in women were those of the breast (35.4), colorectal (12.1), thyroid (10.3), stomach (9.2), and lung (6.7). The incidence rates of upper gastrointestinal and lung cancers were considerably higher in the northern part of this region, including Turkey and northern Iran compared with southern countries. High incidences of breast, colorectal, prostate, and bladder cancers were found in countries located in the northwest including Jordan, Lebanon, and Turkey.

CONCLUSIONS

The most common cancers differed by country. Consequently, cancer control programs must be tailored to the most common types of cancers in each country. Lack of high-quality data for some West Asian countries was the major limitation of this study. Therefore, as the first step of cancer control programs, it is recommended that well-structured population-based cancer registries be established in all of these countries.

Interleukin-12 and interleukin-6 gene polymorphisms and risk of bladder cancer in the Iranian population

Interleukin-12 (IL-12) as an antitumor and interleukin-6 (IL-6) as an inflammatory cytokine, are immunomodulatory products that play important roles in responses in cancers and inflammation. We tested the association between two polymorphisms of IL-12(1188A>C; rs3212227) and IL-6 (-174 C>G) and the risk of bladder cancer in 261 patients and 251 healthy individuals. We also investigated the possible association of these SNPs in patients with high-risk jobs and smoking habits with the incidence of bladder cancer. The genotype distributions of IL-6 (-174 C/G) genotype were similar between the cases and the control groups; however, among patients with smoking habits, the association between IL-6 gene polymorphism and incidence of bladder cancer was significant. After a control adjustment for age and sex, the following results were recorded: CC genotype (OR= 2.11, 95%CI=1.56-2.87, p=0.007), GC genotype (OR=2.18, 95%CI=1.16-4.12, p=0.014) and GC+ CC (OR=2.6, 95%CI=1.43-4.47, p=0.011). A significant risk of bladder cancer was observed for the heterozygous genotype (AC) of IL-12 (OR=1.47, 95%CI=1.01-2.14, p=0.045) in all cases, and among smokers (AC) (OR=3.13, 95%CI=1.82-5.37, p=0.00014), combined AC+CC (OR=3.05, 95%CI=1.8-5.18, p=0.000015). Moreover among high risk job patients, there was more than a 3-fold increased risk of cancer in the carriers of IL-12 beta heterozygous (OR=3.7, 95%CI=2.04-6.57, p=0.000056) and combined AC+CC(OR=3.29, 95%CI=1.58-5.86, p=0.00002) genotypes as compared with the AA genotype with low-risk jobs. As a conclusion, this study suggests that IL-12(3'UTR A>C) and IL-6 (-174 C>G) genotypes are significantly associated with an increased risk of bladder cancer in the Iranian population with smoking habits and/or performing high-risk jobs.

Aberrant methylation of CDH11 predicts a poor outcome for patients with bladder cancer

DNA methylation is one of the major mechanisms via which tumor suppressor gene inactivation occurs. For example, hypermethylation of the promoter region of cadherin 11 (CDH11), a novel tumor suppressor gene, frequently occurs in human cancer. In the current study, the methylation status of CDH11 was investigated in bladder cancer tissue samples, and the correlation with clinicopathological features and patient outcome was assessed. The methylation status of CDH11 was detected in 146 bladder cancer tissues and 37 normal bladder epithelial tissues using methylation-specific polymerase chain reaction (PCR). In addition, CDH11 mRNA expression levels were examined by quantitative PCR. Subsequently, associations between CDH11 methylation and specific clinicopathological characteristics, as well as patient outcome, were analyzed. Aberrant CDH11 promoter hypermethylation was detected in 63.0% (92/146) of bladder cancer tissues, however, no CDH11 methylation was identified in the control samples; this difference was significant (P<0.05). Furthermore, CDH11 mRNA expression levels were significantly lower in the tumor samples with methylated CDH11 compared with the normal bladder epithelium and tumor samples with unmethylated CDH11 (P<0.05). When the methylation status of CDH11 was correlated with the clinicopathological features, it was identified that CDH11 methylation was significantly associated with poor differentiation (P=0.0440), an advanced disease stage (P=0.0350), a larger tumor size (P=0.0013) and multiple tumors (P=0.0390). In addition, patients with methylated CDH11 exhibited significantly poorer outcomes than patients with unmethylated CDH11 (P=0.0004). Furthermore, multivariate Cox proportional hazard analysis indicated that CDH11 methylation was independently associated with a poor outcome in the patients with bladder cancer, with a relative risk of mortality of 6.852 (P=0.0082; 95% confidence interval, 3.461-16.177). The current findings indicate that aberrant CDH11 methylation frequently occurs in bladder cancer, and correlates with malignant behavior and poor outcome. Thus, CDH11 methylation status may be used as an independent prognostic biomarker for patients with bladder cancer.

Incidence of renal carcinoma in non-functioning kidney due to renal pelvic stone disease

The objective of This study was to report our pathological findings in nephrectomy specimens from patients treated for non-functioning hydronephrotic kidney due to renal pelvic stone disease. A total of 97 patients who underwent nephrectomy for non-functioning hydronephrotic kidneys between January, 2011 and June, 2014 were retrospectively reviewed. A non-functioning kidney was defined as one having paper-thin parenchyma on urinary ultrasound or computed tomography, exhibiting no contrast visualization in the collecting duct system on intravenous urography and having a split renal function of <10% on nuclear renal function studies. Following pathological evaluation, 9 patients were diagnosed with xanthogranulomatous pyelonephritis, 9 with malignant tumors and 79 with chronic pyelonephritis. Of the patients with chronic pyelonephritis, 2 also had renal adenomas. The malignant tumors included 3 transitional cell carcinomas (TCC), 2 squamous cell carcinomas (SCC), 3 renal cell carcinomas (RCC) (1 sarcomatoid, 1 papillary and 1 clear cell RCC), whereas 1 patient had concurrent RCC and TCC. In conclusion, non-functioning kidneys, particularly those with kidney stones, should be managed as possible malignancies, due to the higher incidence of malignant tumors in such patients compared with the normal population.

Significance of suppressor of cytokine signaling-3 expression in bladder urothelial carcinoma in relation to proinflammatory cytokines and tumor histopathological grading

BACKGROUND

Bladder cancer is among the five most common malignancies worldwide. Altered expression of suppressor of cytokine signaling -3 (SOCS-3) has been implicated in various types of human cancers; however, its role in bladder cancer is not well established.

AIM

The present study was undertaken to investigate the mRNA expression of SOCS-3 in normal and cancerous bladder tissue and to explore its correlation with urinary levels of some proinflammatory cytokines, cytokeratin-18 (CK -18) and with tumor histopathological grading, in order to evaluate their role as potential diagnostic markers.

MATERIALS AND METHODS

SOCS3 mRNA expression levels were evaluated using quantitative real time PCR. Urinary levels of interleukins 6 and 8 were estimated by enzyme linked immunosorbent assay (ELISA). Cytokeratin-18 expression was analyzed by immuunohistochemistry then validated by ELISA.

RESULTS

SOC3 m RNA expression levels were significantly lower in high grade urothelial carcinoma (0.36±0.12) compared to low grade carcinoma (1.22±0.38) and controls (4.08±0.88), (p<0.001). However, in high grade urothelial carcinoma the urinary levels of IL-6, IL-8, total CK-18(221.33±22.84 pg/ml, 325.2±53.6 pg/ ml, 466.7±57.40 U/L respectively) were significantly higher than their levels in low grade carcinoma (58.6±18.6 pg/ ml, 58.3±50.2 pg/ml, 185.5±60.3 U/L respectively) and controls (50.9±23.0 pg/ml, 7.12±2.74 pg/ml, 106.7±47.3U/L respectively), (p<0.001).

CONCLUSIONS

Advanced grade of urothelial bladder carcinoma is significantly associated with lowered mRNA expression of SOC3 as well as elevated urinary levels of proinflammatory cytokines and CK-18. Furthermore, our results suggested that urinary IL-8, IL-6 and CK-18 may benefit as noninvasive biomarkers for early detection as well as histopathological subtyping of urothelial carcinoma.

Are bladder neoplasms more aggresive in patients with a smoking-related second malignancy?

BACKGROUND

Relationships between smoking and bladder neoplasms, one of the common malignancies, are well-known. Different smoking-related malignancies may occur together. In this study, we evaluated the stage and grade of bladder neoplasms in patients also featuring lung or larynx cancer.

MATERIALS AND METHODS

From January 2006 to February 2012, patients who underwent surgery for bladder neoplasms in our clinic were screened retrospectively. In the evaluation, 5 patients had larynx cancer and 20 patients have lung cancer in addition, all having been smoking for a long time. The bladder tumor stage and grade were investigated in these 25 cases.

RESULTS

Mean age of patients was 66.8 (49-78). In the evaulation, all of 5 patients who had larnyx cancer also had high grade urothelial cancer. One had T2 urothelial, and 3 T1 urothelial cancer. In the same way, all of the 20 patients with lung cancer also have high grade urothelial cancer, three T2, and 13 T1. Bladder cancer stage and grade were determined to be significantly increased in patients with concomitant bladder and lung or larynx cancer.

CONCLUSIONS

In the patients who have smoking releated second malignancy, bladder cancer prognosis appears more aggressive. We now need a larger series and multi-center studies for understanding relevant pathophysiology.

Toxicogenetic profile and cancer risk in Lebanese

An increasing number of genetic polymorphisms in drug-metabolizing enzymes (DME) were identified among different ethnic groups. Some of these polymorphisms are associated with an increased cancer risk, while others remain equivocal. However, there is sufficient evidence that these associations become significant in populations overexposed to environmental carcinogens. Hence, genetic differences in expression activity of both Phase I and Phase II enzymes may affect cancer risk in exposed populations. In Lebanon, there has been a marked rise in reported cancer incidence since the 1990s. There are also indicators of exposure to unusually high levels of environmental pollutants and carcinogens in the country. This review considers this high cancer incidence by exploring a potential gene-environment model based on available DME polymorphism prevalence, and their impact on bladder, colorectal, prostate, breast, and lung cancer in the Lebanese population. The examined DME include glutathione S-transferases (GST), N-acetyltransferases (NAT), and cytochromes P-450 (CYP). Data suggest that these DME influence bladder cancer risk in the Lebanese population. Evidence indicates that identification of a gene-environment interaction model may help in defining future research priorities and preventive cancer control strategies in this country, particularly for breast and lung cancer.

Can reproductive characteristics predict bladder cancer in women with haematuria?

BACKGROUND

Among women with haematuria, defining individuals under high risk for bladder cancer based on reproductive factors prior to cystoscopy would be of great benefit in the management of this condition. The aim of this study was to compare age and reproductive factors such as menopausal status, parity, age at first delivery and age at the last delivery between women who have haematuria with or without bladder cancer.

MATERIALS AND METHODS

A total of 463 patients underwent diagnostic cystoscopy in Duzce University Faculty of Medicine between 1 June 2008 and 1 June 2013. Female patients who presented with persistent microscopic or macroscopic haematuria and underwent standard evaluation for haematuria including urinalysis, urine culture, urine cytology, urinary tract imaging with excretory urography or computerized tomography with contrast enhancement and endoscopic evaluation of the urethra and bladder were included in this study. Exclusion criteria were tobacco use and high risk occupations for bladder cancer such as textile, dry cleaning, painting and etc. Fourteen women had hematuria due to benign conditions, and 18 due to bladder cancer. Data were retrospectively retrieved from the medical records of Duzce University Hospital.

RESULTS

Patients with haematuria due to benign reasons did not significantly differ from patients who were found to have bladder cancer in terms of age (p=0.28), menopausal status (p=0.29), mean parity (p=0.38), being nulliparous (p=0.57), parity ≥ 3 (p=0.22), age ≤ 18 years at first delivery (p=1.00), age ≥ 30 years at last delivery (p=0.26), age ≥ 35 years at last delivery (p=0.23) and percentage of the patients with advanced age (≥ 65 years) (p=0.18).

CONCLUSIONS

It is difficult to predict a high risk for developing bladder cancer in women with haematuria based solely on reproductive factors.