Calretinin as a blood-based biomarker for mesothelioma.

BACKGROUND: Malignant mesothelioma (MM) is a deadly cancer mainly caused by previous exposure to asbestos. With a latency period up to 50 years the incidence of MM is still increasing, even in countries that banned asbestos. Secondary prevention has been established to provide persons at risk regular health examinations. An earlier detection with tumor markers might improve therapeutic options. Previously, we have developed a new blood-based assay for the protein marker calretinin. Aim of this study was the verification of the assay in an independent study population and comparison with the established marker mesothelin. METHODS: For a case-control study in men, a total of 163 cases of pleural MM and 163 controls were available from Australia, another 36 cases and 72 controls were recruited in Germany. All controls had asbestosis and/or plaques. Calretinin and mesothelin were determined by ELISA (enzyme-linked immunosorbent assay) in serum or plasma collected prior to therapy. We estimated the performance of both markers and tested factors potentially influencing marker concentrations like age, sample storage time, and MM subtype. RESULTS: Calretinin was able to detect all major subtypes except for sarcomatoid MM. Calretinin showed a similar performance in Australian and German men. At a pre-defined specificity of 95% the sensitivity of calretinin reached 71% and that of mesothelin 69%, when excluding sarcomatoid MM. At 97% specificity, the combination with calretinin increased the sensitivity of mesothelin from 66% to 75%. Sample storage time did not influence the results. In controls the concentrations of calretinin increased 1.87-fold (95% CI 1.10-3.20) per 10 years of age and slightly more for mesothelin (2.28, 95% CI 1.30-4.00). CONCLUSIONS: Calretinin could be verified as a blood-based marker for MM. The assay is robust and shows a performance that is comparable to that of mesothelin. Retrospective analyses would not be limited by storage time. The high specificity supports a combination of calretinin with other markers. Calretinin is specific for epithelioid and biphasic MM but not the rarer sarcomatoid form. Molecular markers like calretinin and mesothelin are promising tools to improve and supplement the diagnosis of MM and warrant further validation in a prospective study.

Chromosomal alterations in exfoliated urothelial cells from bladder cancer cases and healthy men: a prospective screening study.

BACKGROUND: Chromosomal instability in exfoliated urothelial cells has been associated with the development of bladder cancer. Here, we analyzed the accumulation of copy number variations (CNVs) using fluorescence in situ hybridization in cancer cases and explored factors associated with the detection of CNVs in tumor-free men. METHODS: The prospective UroScreen study was designed to investigate the performance of UroVysion™ and other tumor tests for the early detection of bladder cancer in chemical workers from 2003-2010. We analyzed a database compiling CNVs of chromosomes 3, 7, and 17 and at 9p21 that were detected in 191,434 exfoliated urothelial cells from 1,595 men. We assessed the accumulation of CNVs in 1,400 cells isolated from serial samples that were collected from 18 cancer cases up to the time of diagnosis. A generalized estimating equation model was applied to evaluate the influence of age, smoking, and urine status on CNVs in cells from tumor-free men. RESULTS: Tetrasomy of chromosomes 3, 7 and 17, and DNA loss at 9p21 were the most frequently observed forms of CNV. In bladder cancer cases, we observed an accumulation of CNVs that started approximately three years before diagnosis. During the year prior to diagnosis, cells from men with high-grade bladder cancer accumulated more CNVs than those obtained from cases with low-grade cancer (CNV < 2: 7.5% vs. 1.1%, CNV > 2: 16-17% vs. 9-11%). About 1% of cells from tumor-free men showed polysomy of chromosomes 3, 7, or 17 or DNA loss at 9p21. Men aged ≥50 years had 1.3-fold more cells with CNVs than younger men; however, we observed no further age-related accumulation of CNVs in tumor-free men. Significantly more cells with CNVs were detected in samples with low creatinine concentrations. CONCLUSIONS: We found an accumulation of CNVs during the development of bladder cancer starting three years before diagnosis, with more altered cells identified in high-grade tumors. Also, a small fraction of cells with CNVs were exfoliated into urine of tumor-free men, mainly exhibiting tetraploidy or DNA loss at 9p21. Whether these cells are preferentially cleared from the urothelium or are artifacts needs further exploration.

Dinitrotoluene exposure in the copper mining industry and renal cancer: a case-cohort study.

OBJECTIVES: To evaluate the association between dinitrotoluene (DNT) exposure and renal cancer in a case-cohort study. METHODS: This case-cohort study was conducted among men born between 1920 and 1974 (n=16 441) who were gainfully employed between 1953 and 1990 in one of two copper mines in Mansfeld, Saxony-Anhalt, former German Democratic Republic, and followed up till 31 December 2006. The study included 109 cases with renal cancer identified by record linkage with the Common Cancer Registry of the New Federal States of Germany (GKR) or by a network of pathology institutes. A comparison subcohort of 999 cohort members was selected at random from the total cohort. Duration and intensity of inhalation and dermal exposure to DNT were assessed on the basis of a job exposure matrix. A time-dependent Cox proportional hazards model modified for case-cohort design was used to assess the relationship between cumulative inhalation and dermal DNT exposure and renal cancer. RESULTS: Elevated risks were found for medium (HR=2.73; 95% CI 1.00 to 7.42) and high (HR=1.81; 95% CI 0.75 to 4.33) dermal exposure to DNT. Relative risks for medium inhalation exposure to DNT were not increased (HR=0.93; 95% CI 0.48 to 1.79) while relative risks for high inhalation exposure to DNT were elevated to 1.36 (95% CI 0.84 to 2.21). We found a statistically significant HR of 2.12 (95% CI 1.03 to 4.37) for combined medium or high inhalation and medium or high dermal exposure to DNT. CONCLUSIONS: According to our case-cohort study, dermal and inhalation exposure to DNT is associated with increased renal cancer risk.

Cancer incidence among workers occupationally exposed to dinitrotoluene in the copper mining industry.

PURPOSE: Epidemiological and toxicological studies point to a potential carcinogenic effect of dinitrotoluene (DNT), particularly with respect to renal and urothelial cancer. METHODS: The cohort comprised all men born between 1920 and 1974 (n = 16,441) who were gainfully employed between 1953 and 1990 in one of two underground copper mines in Mansfeld, Saxony-Anhalt, former German Democratic Republic, and who were followed up for cancer incidence, 1961-2005. Incident cancer cases were identified by record linkage with the Common Cancer Registry of the New Laender. Standardized incidence ratios (SIR) were calculated with the general population of Saxony-Anhalt as the reference. RESULTS: Standardized incidence ratios for all cancers were not significantly elevated in the cohort (SIR = 1.04; 95 % confidence intervals (CI) 0.96-1.14). We found an increase in lung cancer (SIR = 1.29; 1.13-1.46), but not in kidney cancer (SIR = 1.01; 95 % CI 0.79-1.27) or bladder cancer (SIR = 1.04; 95 % CI 0.82-1.30). Standardized incidence ratios stratified by duration of employment with DNT exposure indicated moderately increased risks for kidney and bladder cancer in cohort members with longer exposure. CONCLUSIONS: The SIR analysis of workers in the copper mining industry in comparison with the general population of Saxony-Anhalt overall did not indicate increased risks for renal or bladder cancer. However, results by years of exposure to DNT suggested weakly increased risks for outcomes of a priori interest, bladder and kidney cancer. A subsequent case-cohort analysis including expert assessment of DNT exposure and identification of additional cancer cases from a network of pathology institutes will provide further insight into a potential etiologic role of DNT in renal and urothelial cancer.

Screening for bladder cancer with urinary tumor markers in chemical workers with exposure to aromatic amines.

PURPOSE: To validate urinary markers for the early detection of bladder cancer (BC) in chemical workers. METHODS: UroScreen was conducted as a validation study for tumor markers within the frame of a health surveillance program of the German Social Accident Insurance for active or retired workers with former exposure to aromatic amines. From 2003 to 2010, 1,609 men took part in voluntary annual screens. Cytology, the quantitative NMP22(®) assay, and UroVysion™ were applied to 7,091 urine samples. RESULTS: Fifteen out of 21 tumors were detected following test positivity. The UroVysion/NMP22 panel detected 14 out of 21 tumors versus 8 tumors with cytology alone (sensitivity 66.7 vs. 44.4 %, specificity 94.5 vs. 98.5 %). The sensitivity of the panel increased to 85.7 % in samples collected ≤12 months before diagnosis and when papillomas were excluded, compared to 58.3 % with cytology. About 3 % of NMP22 tests were false-positive. UroVysion results overlapped with cytology due to the preselection of atypical cells. NMP22 was less and UroVysion more frequently positive in diluted urine samples. Leukocytes confounded NMP22 but not UroVysion. The low incidence of BC in this study population yielded low positive predictive values of the markers and high costs per tumor detected with screening. CONCLUSIONS: UroVysion in combination with NMP22 detected more cases than cytology alone, at the expense of a lower specificity. High costs per detected case resulted from a lower BC incidence than in the past when levels of occupational exposure to aromatic amines were higher. Currently, it cannot be recommended to apply these markers for screening in asymptomatic workers. The increase in sensitivity is not balanced by the high costs of UroVysion and the false-positive tests of NMP22.

Chromosomal instability and bladder cancer: the UroVysion(TM) test in the UroScreen study.

UNLABELLED: What's known on the subject? and what does the study add?: UroVysion™ is a multicolour fluorescence in situ hybridisation assay that detects DNA gain at chromosomes 3, 7 and 17 and loss at the 9p21 locus in exfoliated urothelial cells. This cell-based test is time-consuming and costly compared with voided urine cytology or other molecular markers for the early detection of bladder cancer. We determined copy number changes at chromosomes 3, 7 and 17 and at the 9p21 locus with UroVysion in a prospective screening study among chemical workers. Strong correlations between DNA gains yield a similar performance in detecting bladder cancer with just one of the probes for chromosomes 3, 7 or 17 instead of all, supporting the development of a simpler and cheaper assay. OBJECTIVE: To explore changes at chromosomes 3, 7, 17 and 9p21 in order to assess associations with bladder cancer for possible improvements of the UroVysion™ assay regarding screening. SUBJECTS AND METHODS: In all, 1609 men took part in the prospective study UroScreen. Annual screening for bladder cancer was offered to male chemical workers with former exposure to aromatic amines as a voluntary surveillance programme between 2003 and 2010. In all, 191 434 cells in 6517 UroVysion tests were analysed for copy number variations (CNV) at chromosome 3, 7, 17 (gains) and 9p21 (deletions) in 1595 men. We assessed CNVs at single or multiple loci using polysomy indices (PIs, called multiple PI and PI 3, PI 7 and PI 17). We calculated Spearman's rank correlation coefficients (rs ) between these PIs and receiver operating characteristic (ROC) curves with areas under the curves (AUCs). We applied Cox regression to estimate hazard ratios (HRs) to assess the risk of developing bladder cancer. RESULTS: Nine out of 21 bladder tumours detected in 20 participants ('cases') had a positive UroVysion test, including seven high-grade carcinomas and seven overlapping results with a positive cytology. Four cases with negative test results did not attend screening annually. No case was found because of a complete loss of 9p21 in at least 12 cells. There were strong correlations between pairwise combinations of gains at chromosome 3, 7 or 17, ranging between rs = 0.98 and rs = 0.99 in cases and between rs = 0.84 and rs = 0.88 in non-cases (P < 0.001). Associations were less pronounced with CNVs at 9p21 among cases and were lacking in non-cases. Estimates of the relative risk of DNA gain for developing a bladder tumour assessed with PIs (threshold 10% of cells) were 47.7 (95% confidence interval [CI] 18.3-124.1) for the multiple PI, 44.5 (95%CI 16.5-119.9) for PI 3, 34.7 (95%CI 13.1-92.1) for PI 7 and 52.4 (95%CI 20.7-132.6) for PI 17, as well as 7.9 (95%CI 3.0-20.6) for a complete loss of 9p21 (threshold 2.5% of cells), respectively. ROC analyses showed similar AUCs for multiple PI compared with PIs of single chromosomes 3, 7 and 17 (all AUCs between 0.79 and 0.80) and a lower AUC for a homozygous loss of 9p21 (AUC 0.72). CONCLUSIONS: The UroVysion assay showed a reasonable performance in detecting bladder cancer in the present study population and shared positive test results with cytology, which is much cheaper. A simpler, faster and cheaper version of the UroVysion assay might rely on the very strong correlations between gains at chromosomes 3, 7 and 17, resulting in a similar performance in detecting bladder cancer with single-probe PIs compared with the full set of these probes. Loss of 9p21 was less predictive for developing bladder cancer in UroScreen.

Nuclear matrix protein-22: a prospective evaluation in a population at risk for bladder cancer. Results from the UroScreen study.

UNLABELLED: What's known on the subject? and What does the study add? The prognosis of bladder cancer significantly depends on tumour stage and time of diagnosis so early diagnosis is desirable to decrease mortality and treatment costs. The NMP22 test is approved for clinical application by the Food and Drug Administration (FDA) of the US. Previous studies have reported values of 47-100% for sensitivity and 58-91% for specificity with this test, but there is no new data on the predictive value of NMP22 for screening bladder cancer (BC). The most important risk factor for BC is the tobacco consumption but occupational exposure to carcinogenic substances, especially aromatic amines, is regarded as another risk factor. The UroScreen study is a prospective longitudinal study for the early detection of BC. To our knowledge, it is the largest prospective validation study conducted over the longest period of time. The study results led us to conclude that, based on the currently available data, NMP22 should not be regarded as an alternative to endoscopy, and we could not make a general recommendation for screening or follow-up. The UroScreen results indicate that urine-based molecular markers could be a suitable addition to urine cytology and the detection of microhaematuria. OBJECTIVE: To evaluate the value of nuclear matrix protein-22 (NMP22) in bladder cancer (BC) screening, and its effect on variables in a prospective study in a high-risk population. PATIENTS AND METHODS: A total of 1772 chemical workers (mean age 62 years) exposed to carcinogenic aromatic amines were enrolled in the study. In all, 7091 screening check-ups in 1609 subjects were performed. Urine samples were collected for a quantitative NMP22 immunoassay, urine analysis and creatinine concentration assessment. Cystoscopy and subsequent transurethral resection were performed where there were suspicious findings. RESULTS: Histopathological analysis found three papillary urothelial neoplasms of low malignant potential, five recurrent BCs and 13 primary BCs. Three tumours were at a muscle-invasive stage (pT2, pT3a or pT3b). We found higher NMP22 concentrations (>10 U/mL) in 224 patients, which correctly predicted BC in six cases (sensitivity 97.29%, specificity 28.57%; negative predictive value 99.04%, positive predictive value 12.24%). Gross haematuria affected NMP22 results (odd ratio [OR] 3.49, 95% confidence interval [CI] 1.81-6.73). Infection also affected NMP22 results (OR 4.13, 95% CI 2.31-7.35). NMP22 was more frequently positive in urine with creatinine concentration >2.5 g/L (OR 1.61, 95% CI 0.91-2.86). CONCLUSIONS: NMP22 outcomes are affected by haematuria, infection and concentrated urine. NMP22 alone cannot be recommended for primary screening in a high-risk population nor as an alternative to cystoscopy during follow-up. A NMP22 test might be a useful adjunct to urine cytology.

Exposure to inhalable, respirable, and ultrafine particles in welding fume.

This investigation aims to explore determinants of exposure to particle size-specific welding fume. Area sampling of ultrafine particles (UFP) was performed at 33 worksites in parallel with the collection of respirable particles. Personal sampling of respirable and inhalable particles was carried out in the breathing zone of 241 welders. Median mass concentrations were 2.48 mg m(-3) for inhalable and 1.29 mg m(-3) for respirable particles when excluding 26 users of powered air-purifying respirators (PAPRs). Mass concentrations were highest when flux-cored arc welding (FCAW) with gas was applied (median of inhalable particles: 11.6 mg m(-3)). Measurements of particles were frequently below the limit of detection (LOD), especially inside PAPRs or during tungsten inert gas welding (TIG). However, TIG generated a high number of small particles, including UFP. We imputed measurements

Stability of targeted metabolite profiles of urine samples under different storage conditions.

INTRODUCTION: Few studies have investigated the influence of storage conditions on urine samples and none of them used targeted mass spectrometry (MS). OBJECTIVES: We investigated the stability of metabolite profiles in urine samples under different storage conditions using targeted metabolomics. METHODS: Pooled, fasting urine samples were collected and stored at -80 °C (biobank standard), -20 °C (freezer), 4 °C (fridge), ~9 °C (cool pack), and ~20 °C (room temperature) for 0, 2, 8 and 24 h. Metabolite concentrations were quantified with MS using the AbsoluteIDQ™ p150 assay. We used the Welch-Satterthwaite-test to compare the concentrations of each metabolite. Mixed effects linear regression was used to assess the influence of the interaction of storage time and temperature. RESULTS: The concentrations of 63 investigated metabolites were stable at -20 and 4 °C for up to 24 h when compared to samples immediately stored at -80 °C. When stored at ~9 °C for 24 h, few amino acids (Arg, Val and Leu/Ile) significantly decreased by 40% in concentration (P < 7.9E-04); for an additional three metabolites (Ser, Met, Hexose H1) when stored at ~20 °C reduced up to 60% in concentrations. The concentrations of four more metabolites (Glu, Phe, Pro, and Thr) were found to be significantly influenced when considering the interaction between exposure time and temperature. CONCLUSION: Our findings indicate that 78% of quantified metabolites were stable for all examined storage conditions. Particularly, some amino acid concentrations were sensitive to changes after prolonged storage at room temperature. Shipping or storing urine samples on cool packs or at room temperature for more than 8 h and multiple numbers of freeze and thaw cycles should be avoided.

Circulating miR-132-3p as a Candidate Diagnostic Biomarker for Malignant Mesothelioma.

The use of circulating microRNAs as biomarkers has opened new opportunities for diagnosis of cancer because microRNAs exhibit tumor-specific expression profiles. The aim of this study was the identification of circulating microRNAs in human plasma as potential biomarkers for the diagnosis of malignant mesothelioma. For discovery, TaqMan Low Density Array Human MicroRNA Cards were used to analyze 377 microRNAs in plasma samples from 21 mesothelioma patients and 21 asbestos-exposed controls. For verification, individual TaqMan microRNA assays were used for quantitative real-time PCR in plasma samples from 22 mesothelioma patients and 44 asbestos-exposed controls. The circulating miR-132-3p showed different expression levels between mesothelioma patients and asbestos-exposed controls. For discrimination, sensitivity of 86% and specificity of 61% were calculated. Circulating miR-132-3p in plasma was not affected by hemolysis and no impact of age or smoking status on miR-132-3p levels could be observed. For the combination of miR-132-3p with the previously described miR-126, sensitivity of 77% and specificity of 86% were calculated. The results of this study indicate that miR-132-3p might be a new promising diagnostic biomarker for malignant mesothelioma. It is indicated that the combination of miR-132-3p with other individual biomarkers improves the biomarker performance.

Development of a multi-compartment pharmacokinetic model to characterize the exposure to Hexamoll® DINCH®.

We developed and calibrated a multi compartment pharmacokinetic (PK) model to predict urinary concentrations after oral exposure of four specific DINCH metabolites: MINCH, OH-MINCH, cx-MINCH, and oxo-MINCH. This descriptive model has 4 compartments: a "stomach" (SC) compartment, a "holding" (HC) compartment, a "blood" (BC) compartment and a "bladder" (BLC) compartment. DINCH is assumed to first deposit into the SC, with transfer split between the HC and the BC. Unmetabolized DINCH from the HC then transfers to the BC. The DINCH metabolism is assumed to occur in the BC before excretion via the BLC. At each urination event, all the metabolite mass in the BLC is excreted. The model was calibrated using published urine metabolite data from 3 different male volunteers, each orally dosed with 50mg DINCH. Full urine voids were taken for 48 h after dosage. The predicted values showed a good agreement with the observed urinary DINCH metabolite concentrations, with a Spearman correlation coefficient exceeding 0.7 for all oxidized metabolites. We showed the importance of a holding reservoir. Without it, a good agreement could not be found. We applied the model to a set of 24-h general population samples measured for DINCH metabolites. The model was unable to duplicate the ratio of metabolites seen in the 24-h samples. Two possibilities were offered to explain the difference: the exposure pattern in the general population did not match the oral exposure in the dosing experiments, or the long-term toxicokinetics of DINCH was not captured in the 48-h controlled dosing experiments.

Levels and predictors of airborne and internal exposure to chromium and nickel among welders--results of the WELDOX study.

The objective of this analysis was to investigate levels and determinants of exposure to airborne and urinary chromium (Cr, CrU) and nickel (Ni, NiU) among 241 welders. Respirable and inhalable welding fume was collected during a shift, and the metal content was determined using inductively coupled plasma mass spectrometry. In post-shift urine, CrU and NiU were measured by means of graphite furnace atom absorption spectrometry, with resulting concentrations varying across a wide range. Due to a large fraction below the limits of quantitation we applied multiple imputations to the log-transformed exposure variables for the analysis of the data. Respirable Cr and Ni were about half of the concentrations of inhalable Cr and Ni, respectively. CrU and NiU were determined with medians of 1.2 µg/L (interquartile range <1.00; 3.61) and 2.9 µg/L (interquartile range <1.50; 5.97). Furthermore, Cr and Ni correlated in respirable welding fume (r=0.79, 95% CI 0.74-0.85) and urine (r=0.55, 95% CI 0.44-0.65). Regression models identified exposure-modulating variables in form of multiplicative factors and revealed slightly better model fits for Cr (R(2) respirable Cr 48%, CrU 55%) than for Ni (R(2) respirable Ni 42%, NiU 38%). The air concentrations were mainly predicted by the metal content in electrodes or base material in addition to the welding technique. Respirable Cr and Ni were good predictors for CrU and NiU, respectively. Exposure was higher when welding was performed in confined spaces or with inefficient ventilation, and lower in urine when respirators were used. In conclusion, statistical modelling allowed the evaluation of determinants of internal and external exposure to Cr and Ni in welders. Welding parameters were stronger predictors than workplace conditions. Airborne exposure was lowest inside respirators with supply of purified air.

Prospective evaluation of fluorescence-in situ-hybridization to detect bladder cancer: results from the UroScreen-Study.

BACKGROUND: UroScreen is a prospective study for early diagnosis of bladder cancer (BC) in chemical workers formerly exposed to aromatic amines, aimed to assess the performance of molecular tumor markers in comparison with urinary cytology. Here we evaluate the cancer-predictive values and potential effect modifiers of fluorescence-in-situ-hybridization (FISH). SUBJECTS AND METHODS: A FISH test was performed in 7,091 urine samples from 1,609 subjects between 2007 and 2010. Cystoscopy was recommended in case of positive or suspicious findings. Logistic regression models were applied to estimate the influence of potential test confounders like urinary creatinine and hematuria on detecting BC. Receiver operating characteristic (ROC) curves for FISH were adjusted for test confounders. Cancer-predictive values were calculated from test results in the last sample before diagnosis. RESULTS: Histopathology revealed 16 incidental BCs and 5 recurrent tumors in 20 study participants. FISH was positive in 9 BC cases of which 7 were high grade. Cytology detected 8 tumors. FISH overlapped with cytology in 7 cases. Sensitivity was 45.0% and PPV (positive predictive value) was 16.4% in all and 53.85% and 13.21% in high-grade tumors. Specificity and negative predictive value (NPV) were 96.97% and 99.26% in all bladder tumors. BC detected during UroScreen was associated with an odds ratio (OR) of 6.88 (95% CI 1.72-27.44) for positive FISH and with an OR of 8.81 (95% CI 1.41-54.96) for gross hematuria. The adjusted area under the curve was 0.77 (95% CI 0.62-0.92) for all and for high-grade lesions (0.85; 95% CI 0.69-1.00). CONCLUSIONS: FISH showed a performance in detecting bladder cancer comparable to cytology but a larger number or false-positive results. It remains to be investigated if chromosomal instability can be detected earlier than morphologic changes of exfoliated bladder cancer cells.

N-acetyltransferase 2 phenotype, occupation, and bladder cancer risk: results from the EPIC cohort.

BACKGROUND: An association between N-acetyltransferase 2 (NAT2) slow acetylation and bladder cancer has been consistently observed in epidemiologic studies. However, evidence has been mainly derived from case-control studies and was sparse from cohort studies. We evaluated the association between NAT2 slow acetylation and bladder cancer in a case-control study nested in the European Prospective Investigation into Cancer and Nutrition. METHODS: Exposure to aromatic amines and polycyclic aromatic hydrocarbons (PAH) could be assessed for 754 cases and 833 controls for whom occupational information was documented. A semiquantitative job-exposure matrix was applied to at-risk occupations to estimate the exposure as low, medium, or high based on tertiles of the distribution of the exposure score in controls. Using a comprehensive genotyping, NAT2 acetylation status could be categorized from 6-single-nucleotide polymorphism genotypes as slow or fast in 607 cases and 695 controls with DNA from archived blood samples. RESULTS: Occupational exposure to aromatic amines and PAH was associated with an increased bladder cancer risk [upper tertile of the distribution of the exposure score: OR = 1.37; 95% confidence interval (CI), 1.02-1.84, and OR = 1.50; 95% CI, 1.09-2.05, respectively]. NAT2 slow acetylation did not modify these risk estimates and was not itself associated with bladder cancer risk (OR = 1.02; 95% CI, 0.81-1.29). CONCLUSIONS: These findings confirm established or suspected occupational risk factors but not the anticipated role of NAT2 slow acetylation in bladder cancer. No interaction was detected between NAT2 and any exposure of interest, including smoking. IMPACT: Genetic testing for NAT2 would be inappropriate in occupational settings.

Relation between biomarkers in exhaled breath condensate and internal exposure to metals from gas metal arc welding.

Concerning possible harmful components of welding fumes, besides gases and quantitative aspects of the respirable welding fumes, particle-inherent metal toxicity has to be considered.The objective of this study was to investigate the effect markers leukotriene B4 (LTB4),prostaglandin E2 (PGE2) and 8-isoprostane (8-Iso PGF2α) as well as the acid­base balance(pH) in exhaled breath condensate (EBC) of 43 full-time gas metal arc welders (20 smokers) in relation to welding fume exposure. We observed different patterns of iron, chromium and nickel in respirable welding fumes and EBC. Welders with undetectable chromium in EBC(group A, n = 24) presented high iron and nickel concentrations. In this group, higher 8-isoPGF2α and LTB4 concentrations could be revealed compared to welders with detectable chromium and low levels of both iron and nickel in EBC (group B): 8-iso PGF2α443.3 pg mL−1 versus 247.2 pg mL−1; p = 0.001 and LTB4 30.5 pg mL−1 versus 17.3 pgmL−1; p = 0.016. EBC-pH was more acid in samples of group B (6.52 versus 6.82; p = 0.011).Overall, effect markers in welders were associated with iron concentrations in EBC according to smoking habits--non-smokers/smokers: LTB4 (rs = 0.48; p = 0.02/rs = 0.21; p = 0.37),PGE2 (rs = 0.15; p = 0.59/rs = 0.47; p = 0.07), 8-iso PGF2α (rs = 0.18; p = 0.54/rs = 0.59;p = 0.06). Sampling of EBC in occupational research provides a matrix for the simultaneous monitoring of metal exposure and effects on target level. Our results suggest irritative effects in the airways of healthy welders. Further studies are necessary to assess whether these individual results might be used to identify welders at elevated risk for developing a respiratory disease.

Performance of survivin mRNA as a biomarker for bladder cancer in the prospective study UroScreen.

BACKGROUND: Urinary biomarkers have the potential to improve the early detection of bladder cancer. Most of the various known markers, however, have only been evaluated in studies with cross-sectional design. For proper validation a longitudinal design would be preferable. We used the prospective study UroScreen to evaluate survivin, a potential biomarker that has multiple functions in carcinogenesis. METHODS/RESULTS: Survivin was analyzed in 5,716 urine samples from 1,540 chemical workers previously exposed to aromatic amines. The workers participated in a surveillance program with yearly examinations between 2003 and 2010. RNA was extracted from urinary cells and survivin was determined by Real-Time PCR. During the study, 19 bladder tumors were detected. Multivariate generalized estimation equation (GEE) models showed that ß-actin, representing RNA yield and quality, had the strongest influence on survivin positivity. Inflammation, hematuria and smoking did not confound the results. Survivin had a sensitivity of 21.1% for all and 36.4% for high-grade tumors. Specificity was 97.5%, the positive predictive value (PPV) 9.5%, and the negative predictive value (NPV) 99.0%. CONCLUSIONS: In this prospective and so far largest study on survivin, the marker showed a good NPV and specificity but a low PPV and sensitivity. This was partly due to the low number of cases, which limits the validity of the results. Compliance, urine quality, problems with the assay, and mRNA stability influenced the performance of survivin. However, most issues could be addressed with a more reliable assay in the future. One important finding is that survivin was not influenced by confounders like inflammation and exhibited a relatively low number of false-positives. Therefore, despite the low sensitivity, survivin may still be considered as a component of a multimarker panel.