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A series of Mn(I), Fe(II), and Co(II) complexes with PN H ligands bearing secondary amine functionality were prepared and tested in the catalytic transfer hydrogenation of nitriles using ammonia borane as a hydrogen source. Among all tested complexes, a tetracoordinate Fe(II) bromide, (PN H )FeBr 2 , proved the most effective, representing a rare example of a highly active iron-based catalytic system for transfer hydrogenation reactions beyond carbonyl compounds and the first example of the iron catalyst for the transfer hydrogenation of nitriles to the corresponding primary amines. Mechanistic studies point out a metal-ligand cooperative mechanism enabled by the secondary amine moiety of the PN H ligand.

Hydroboration of isocyanates with HBPin was demonstrated using both catalytic and catalyst-free approaches. In arene solvents, the reactions employed the commercially available and bench-stable Co(acac) 2 /dpephos (dpephos = bis[(2-diphenylphosphino)phenyl] ether) pre-catalyst and proved chemodivergent, showing the formation of either formamides or N -methylamines, depending on the concentration of HBPin and the reaction conditions used. Catalytic monohydroboration of isocyanates to formamides was found to be highly chemoselective, tolerating alkenes, alkynes, aryl halides, esters, carboxamides, nitriles, nitroarenes and heteroaromatic functionalities. The catalyst-free hydroboration reactions have been demonstrated in neat HBPin. Whereas monohydroboration proved less selective compared with Co(acac) 2 /dpephos-catalyzed transformations, selective deoxygenative hydroboration of isocyanates to N -methylamines was observed under catalyst-free conditions.

The commercially available and bench-stable Co(acac) 2 /dpephos system is employed as a precatalyst for selective and efficient room temperature hydroboration of organic nitriles with HBPin to produce a series of N,N-diborylamines [RN(BPin) 2 ], which react in situ with aldehydes to give aldimines. Formation of aldimines from N,N-diborylamines does not require a dehydrating agent, is applicable to a wide range of N,N-diborylamine and aldehyde substrates and is highly chemoselective, being unaffected by various common functional groups, such as alkenes, alkynes, secondary amines, ketones, esters, amides, carboxylic acids, pyridines, nitriles, and nitro compounds. The overall transformation represents a synthetically valuable approach to aldimines from nitriles and can be performed in a sequential one-pot manner, tolerating ester, lactone, carboxamide and unactivated alkene functionalities., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: We aimed to assess the association of oral health (OH), dental care (DC) and mouthwash with upper-aerodigestive tract (UADT) cancer risk, and to examine the extent that enzymes involved in the metabolism of alcohol modify the effect of mouthwash., Materials and Methods: The study included 1963 patients with incident cancer of the oral cavity, oropharynx, hypopharynx, larynx or esophagus and 1993 controls. Subjects were interviewed about their oral health and dental care behaviors (which were converted to scores of OH and DC respectively), as well as smoking, alcohol drinking, diet, occupations, medical conditions and socio-economic status. Blood samples were taken for genetic analyses. Mouthwash use was analyzed in relation to the presence of polymorphisms of alcohol-metabolizing genes known to be associated with UADT. Adjusted odds ratios (ORs) and 95%-confidence intervals [CI] were estimated with multiple logistic regression models adjusting for multiple confounders., Results: Fully adjusted ORs of low versus high scores of DC and OH were 2.36[CI=1.51-3.67] and 2.22[CI=1.45-3.41], respectively, for all UADT sites combined. The OR for frequent use of mouthwash use (3 or more times/day) was 3.23[CI=1.68-6.19]. The OR for the rare variant ADH7 (coding for fast ethanol metabolism) was lower in mouthwash-users (OR=0.53[CI=0.35-0.81]) as compared to never-users (OR=0.97[CI=0.73-1.29]) indicating effect modification (pheterogeneity=0.065) while no relevant differences were observed between users and non-users for the variant alleles of ADH1B, ADH1C or ALDH2., Conclusions: Poor OH and DC seem to be independent risk factors for UADT because corresponding risk estimates remain substantially elevated after detailed adjustment for multiple confounders. Whether mouthwash use may entail some risk through the alcohol content in most formulations on the market remains to be fully clarified., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

We investigated the association between occupational history and upper aerodigestive tract (UADT) cancer risk in the ARCAGE European case-control study. The study included 1,851 patients with incident cancer of the oral cavity, oropharynx, hypopharynx, larynx or esophagus and 1,949 controls. We estimated odds ratios (OR) and 95% confidence intervals (CI) for ever employment in 283 occupations and 172 industries, adjusting for smoking and alcohol. Men (1,457 cases) and women (394 cases) were analyzed separately and we incorporated a semi-Bayes adjustment approach for multiple comparisons. Among men, we found increased risks for occupational categories previously reported to be associated with at least one type of UADT cancer, including painters (OR = 1.74, 95% CI: 1.01-3.00), bricklayers (1.58, 1.05-2.37), workers employed in the erection of roofs and frames (2.62, 1.08-6.36), reinforced concreters (3.46, 1.11-10.8), dockers (2.91, 1.05-8.05) and workers employed in the construction of roads (3.03, 1.23-7.46), general construction of buildings (1.44, 1.12-1.85) and cargo handling (2.60, 1.17-5.75). With the exception of the first three categories, risks both increased when restricting to long duration of employment and remained elevated after semi-Bayes adjustment. Increased risks were also found for loggers (3.56, 1.20-10.5) and cattle and dairy farming (3.60, 1.15-11.2). Among women, there was no clear evidence of increased risks of UADT cancer in association with occupations or industrial activities. This study provides evidence of an association between some occupational categories and UADT cancer risk among men. The most consistent findings, also supported by previous studies, were obtained for specific workers employed in the construction industry., (Copyright © 2011 UICC.)

Background: The study aimed to investigate the role of medical history (skin warts, Candida albicans, herpetic lesions, heartburn, regurgitation) and medication use (for heartburn; for regurgitation; aspirin) in the aetiology of upper aerodigestive tract (UADT) cancer., Methods: A multicentre (10 European countries) case-control study [Alcohol-Related CAncers and GEnetic susceptibility (ARCAGE) project]., Results: There were 1779 cases of UADT cancer and 1993 controls. History of warts or C. albicans infection was associated with a reduced risk [odds ratio (OR) 0.80, 95% confidence interval (CI) 0.68-0.94 and OR 0.73, 95% CI 0.60-0.89, respectively] but there was no association with herpetic lesions, heartburn, regurgitation or medication for related symptoms. Regurgitation was associated with an increased risk for cancer of the oesophagus (OR 1.47, 95% CI 0.98-2.21). Regular aspirin use was not associated with risk of UADT cancer overall but was associated with a reduced risk for cancer of oesophagus (OR 0.51, 95% CI 0.28-0.96), hypopharynx (OR 0.53, 95% CI 0.28-1.02) and larynx (OR 0.74, 95% CI 0.54-1.01)., Conclusions: A history of some infections appears to be a marker for decreased risk of UADT cancer. The role of medical history and medication use varied by UADT subsites with aspirin use associated with a decreased risk of oesophageal cancer and suggestive of a decreased risk of hypopharyngeal and laryngeal cancers.

Renal cell carcinoma (RCC) is the most lethal urologic cancer. Only two common susceptibility loci for RCC have been confirmed to date. To identify additional RCC common susceptibility loci, we conducted an independent genome-wide association study (GWAS). We analyzed 533 191 single nucleotide polymorphisms (SNPs) for association with RCC in 894 cases and 1516 controls of European descent recruited from MD Anderson Cancer Center in the primary scan, and validated the top 500 SNPs in silico in 3772 cases and 8505 controls of European descent involved in the only published GWAS of RCC. We identified two common variants in linkage disequilibrium, rs718314 and rs1049380 (r(2) = 0.64, D ' = 0.84), in the inositol 1,4,5-triphosphate receptor, type 2 (ITPR2) gene on 12p11.23 as novel susceptibility loci for RCC (P = 8.89 × 10(-10) and P = 6.07 × 10(-9), respectively, in meta-analysis) with an allelic odds ratio of 1.19 [95% confidence interval (CI): 1.13-1.26] for rs718314 and 1.18 (95% CI: 1.12-1.25) for rs1049380. It has been recently identified that rs718314 in ITPR2 is associated with waist-hip ratio (WHR) phenotype. To our knowledge, this is the first genetic locus associated with both cancer risk and WHR., (© The Author 2011. Published by Oxford University Press. All rights reserved.)

Tobacco and alcohol are major risk factors for upper aerodigestive tract (UADT) cancer and significant variation is observed in UADT cancer rates across Europe. We have estimated the proportion of UADT cancer burden explained by tobacco and alcohol and how this varies with the incidence rates across Europe, cancer sub-site, gender and age. This should help estimate the minimum residual burden of other risk factors to UADT cancer, including human papillomavirus. We analysed 1981 UADT cancer cases and 1993 controls from the ARCAGE multicentre study. We estimated the population attributable risk (PAR) of tobacco alone, alcohol alone and their joint effect. Tobacco and alcohol together explained 73% of UADT cancer burden of which nearly 29% was explained by smoking alone, less than 1% due to alcohol on its own and 44% by the joint effect of tobacco and alcohol. Tobacco and alcohol together explained a larger proportion of hypopharyngeal/laryngeal cancer (PAR=85%) than oropharyngeal (PAR=74%), esophageal (PAR=67%) and oral cancer (PAR=61%). Tobacco and alcohol together explain only about half of the total UADT cancer burden among women. Geographically, tobacco and alcohol explained a larger proportion of UADT cancer in central (PAR=84%) than southern (PAR=72%) and western Europe (PAR=67%). While the majority of the UADT cancers in Europe are due to tobacco or the joint effect of tobacco and alcohol, our results support a significant role for other risk factors in particular, for oral and oropharyngeal cancers and also for UADT cancers in southern and western Europe., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Background: Occupational exposures to dusts have generally been examined in relation to cancers of the respiratory system and have rarely been examined in relation to other cancers, such as renal cell carcinoma (RCC). Although previous epidemiological studies, though few, have shown certain dusts, such as asbestos, to increase renal cancer risk, the potential for other occupational dust exposures to cause kidney damage and/or cancer may exist. We investigated whether asbestos, as well as 20 other occupational dust exposures, were associated with RCC risk in a large European, multi-center, hospital-based renal case-control study., Methods: General occupational histories and job-specific questionnaires were reviewed by occupational hygienists for subject-specific information. Odds ratios (ORs) and 95% confidence intervals (95% CIs) between RCC risk and exposures were calculated using unconditional logistic regression., Results: Among participants ever exposed to dusts, significant associations were observed for glass fibres (OR: 2.1; 95% CI: 1.1-3.9), mineral wool fibres (OR: 2.5; 95% CI: 1.2-5.1), and brick dust (OR: 1.5; 95% CI: 1.0-2.4). Significant trends were also observed with exposure duration and cumulative exposure. No association between RCC risk and asbestos exposure was observed., Conclusion: Results suggest that increased RCC risk may be associated with occupational exposure to specific types of dusts. Additional studies are needed to replicate and extend findings.

Introduction: Folate and one-carbon metabolism are linked to cancer risk through their integral role in DNA synthesis and methylation. Variation in one-carbon metabolism genes, particularly MTHFR, has been associated with risk of a number of cancers in epidemiologic studies, but little is known regarding renal cancer., Methods: Tag single nucleotide polymorphisms (SNPs) selected to produce high genomic coverage of 13 gene regions of one-carbon metabolism (ALDH1L1, BHMT, CBS, FOLR1, MTHFR, MTR, MTRR, SHMT1, SLC19A1, TYMS) and the closely associated glutathione synthesis pathway (CTH, GGH, GSS) were genotyped for 777 renal cell carcinoma (RCC) cases and 1,035 controls in the Central and Eastern European Renal Cancer case-control study. Associations of individual SNPs (n = 163) with RCC risk were calculated using unconditional logistic regression adjusted for age, sex and study center. Minimum p-value permutation (Min-P) tests were used to identify gene regions associated with risk, and haplotypes were evaluated within these genes., Results: The strongest associations with RCC risk were observed for SLC19A1 (P(min-P) = 0.03) and MTHFR (P(min-P) = 0.13). A haplotype consisting of four SNPs in SLC19A1 (rs12483553, rs2838950, rs2838951, and rs17004785) was associated with a 37% increased risk (p = 0.02), and exploratory stratified analysis suggested the association was only significant among those in the lowest tertile of vegetable intake., Conclusions: To our knowledge, this is the first study to comprehensively examine variation in one-carbon metabolism genes in relation to RCC risk. We identified a novel association with SLC19A1, which is important for transport of folate into cells. Replication in other populations is required to confirm these findings.

Objectives: Pancreatic carcinoma etiology and molecular pathogenesis is weakly understood. According to the assumption that genetic variation in carcinogen metabolism further modifies the risk of exposure-related cancers, an association of functional polymorphisms in oxidative stress-modifying genes superoxide dismutase 2 (SOD2 [Ala16Val, rs4880]), SOD3 (Arg231Gly, rs1799895), nicotinamide adenine dinucleotide phosphate:quinone oxidoreductase (NQO1 [Pro187Ser, rs1800566], and NQO2 (Phe47Leu, rs1143684) with pancreatic cancer risk was studied., Methods: Polymorphisms were studied by allelic discrimination., Results: In a hospital-based case-control study on 500 individuals (235 cases and 265 controls) of Czech white origin, SOD2, SOD3, NQO1, and NQO2 polymorphisms showed no significant association with pancreatic cancer risk. Major lifestyle factors such as smoking and alcohol, coffee, or tea consumption did not modify the effect of the studied polymorphisms., Conclusions: The first European study of the SOD2, SOD3, NQO1, and NQO2 roles in pancreatic cancer etiology did not find significant associations. Despite this observation, other populations with different lifestyle(s) may be at risk and should be further studied.

Background: Epidemiologic studies are reporting associations between lead exposure and human cancers. A polymorphism in the 5-aminolevulinic acid dehydratase (ALAD) gene affects lead toxicokinetics and may modify the adverse effects of lead., Methods: The objective of this study was to evaluate single-nucleotide polymorphisms (SNPs) tagging the ALAD region among renal cancer cases and controls to determine whether genetic variation alters the relationship between lead and renal cancer. Occupational exposure to lead and risk of cancer was examined in a case-control study of renal cell carcinoma (RCC). Comprehensive analysis of variation across the ALAD gene was assessed using a tagging SNP approach among 987 cases and 1298 controls. Occupational lead exposure was estimated using questionnaire-based exposure assessment and expert review. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression., Results: The adjusted risk associated with the ALAD variant rs8177796(CT/TT) was increased (OR = 1.35, 95%CI = 1.05-1.73, p-value = 0.02) when compared to the major allele, regardless of lead exposure. Joint effects of lead and ALAD rs2761016 suggest an increased RCC risk for the homozygous wild-type and heterozygous alleles ((GG)OR = 2.68, 95%CI = 1.17-6.12, p = 0.01; (GA)OR = 1.79, 95%CI = 1.06-3.04 with an interaction approaching significance (p(int) = 0.06). No significant modification in RCC risk was observed for the functional variant rs1800435(K68N). Haplotype analysis identified a region associated with risk supporting tagging SNP results., Conclusion: A common genetic variation in ALAD may alter the risk of RCC overall, and among individuals occupationally exposed to lead. Further work in larger exposed populations is warranted to determine if ALAD modifies RCC risk associated with lead exposure.

Background: The incidence of cancers of the upper aerodigestive tract (UADT) is increasing throughout the world. To date the increases have been proportionally greatest among young people. Several reports have suggested that they often do not have a history of tobacco smoking or heavy alcohol consumption., Objective: To determine the contribution of lifestyle factors to the etiology of UADT cancers occurring in those aged less than 50 years., Methods: A case-control study was conducted in 10 European countries. Cases were cancers of the oral cavity and pharynx, larynx and esophagus, and hospital or population controls were age and sex matched., Results: There were 356 cases younger than 50 years and 419 controls. Risk was strongly related to current smoking [odds ratio (OR) 5.5 95%; confidence interval (CI) (3.3, 9.2)], and risk increased with number of pack-years smoked. Risk was also related to alcohol consumption for both current (OR 1.8; 0.97, 3.3) and past (OR 3.4; 1.6, 7.4) drinkers, and risk increased with number of drink-years. Persons frequently consuming fruits and vegetables were at significantly reduced risk., Conclusions: Risk factors already identified as being important for UADT cancers in adults are also important influences on risk in younger adults. The implication of these results is that the public health message in preventing UADT cancers remains the same to young and old alike.

In the first case-control study on pancreatic cancer conducted on 253 cases and 403 controls in the Czech Republic we observed that the GSTP1-codon 105 Val variant allele and the GSTT1-null genotype were associated with an elevated risk for pancreatic cancer (OR = 1.38; 95%CI = 0.96-1.97 and OR = 1.56; 95%CI = 0.93-2.61, respectively). Combination of GSTT1-null and GSTP1-codon 105 Val variants further increased the risk for pancreatic cancer (OR = 2.50; 95%CI = 1.20-5.20). In conclusion, this study suggests population-specific associations of polymorphisms in key biotransformation genes with elevated risk for pancreatic cancer.

There is suggestive, but inconclusive, evidence that dietary factors may affect risk of cancers of the upper aerodigestive tract (UADT). In the context of the alcohol-related cancers and genetic susceptibility in Europe study, we have examined the association of dietary factors with UADT cancer risk. We have analyzed data from 2,304 patients with UADT cancer and 2,227 control subjects recruited in 14 centers in 10 European countries. Dietary data were collected through a semi-quantitative food frequency questionnaire that also assessed preferred temperature of hot beverages. Statistical analyses were conducted through multiple logistic regression controlling for potential confounding variables, including alcohol intake and smoking habits. Consumption of red meat (OR per increasing tertile = 1.14, 95% CI: 1.05-1.25), but not poultry, was significantly associated with increased UADT cancer risk and the association was somewhat stronger for esophageal cancer. Consumption of fruits (OR per increasing tertile = 0.68, 95% CI: 0.62-0.75) and vegetables (OR per increasing tertile = 0.73, 95% CI: 0.66-0.81) as well as of olive oil (OR for above versus below median = 0.78, 95% CI 0.67-0.90) and tea (OR for above versus below median = 0.83, 95% CI 0.69-0.98) were significantly associated with reduced risk of UADT cancer. There was no indication that an increase in tea or coffee temperature was associated with increased risk of UADT overall or cancer of the esophagus; in fact, the association was, if anything, inverse. In conclusion, the results of this large multicentric study indicate that diet plays an important role in the etiology of UADT cancer.

Cancers of the upper aerodigestive tract (UADT) include those of the oral cavity, pharynx (other than nasopharynx), larynx, and esophagus. Tobacco smoking and consumption of alcoholic beverages are established causes of UADT cancers, whereas reduced intake of vegetables and fruits are likely causes. The role of genetic predisposition and possible interactions of genetic with exogenous factors, however, have not been adequately studied. Moreover, the role of pattern of smoking and drinking, as well as the exact nature of the implicated dietary variables, has not been clarified. To address these issues, the International Agency for Research on Cancer initiated in 2002 the alcohol-related cancers and genetic susceptibility (ARCAGE) in Europe project, with the participation of 15 centers in 11 European countries. Information and biological data from a total of 2304 cases and 2227 controls have been collected and will be used in a series of analyses. A total of 166 single nucleotide polymorphisms of 76 genes are being studied for genetic associations with UADT cancers. We report here the methodology of the ARCAGE project, main demographic and lifestyle characteristics of the cases and controls, as well as the distribution of cases by histology and subsite. About 80% of cases were males and fewer than 20% of all cases occurred before the age of 50 years. Overall, the most common subsite was larynx, followed by oral cavity, oropharynx, esophagus and hypopharynx. Close to 90% of UADT cancers were squamous cell carcinomas. A clear preponderance of smokers and alcohol drinkers among UADT cases compared with controls was observed.

Several industry-based cohort studies have addressed the risk of lung cancer following exposure to vinyl chloride, acrylonitrile and styrene, with inconsistent results and usually without smoking adjustment. These exposures are addressed here in a large case-control study with full adjustment for smoking. Almost 6000 subjects were included in a case-control study conducted in seven European countries. For each job they held, local experts assessed the exposure to a number of occupational agents, including vinyl chloride, acrylonitrile and styrene, on the basis of detailed occupational questionnaires. Information on tobacco consumption and other risk factors was also collected. The odds ratio (OR) for ever exposure to vinyl chloride was 1.05 (95% confidence interval, CI: 0.68-1.62) and a modest, non-significant increase in the risk of lung cancer was found in the highest exposed subgroup. The OR for ever exposure to acrylonitrile was 2.20 (95% CI: 1.11-4.36) with a positive dose-response relationship between estimated cumulative exposure and lung cancer risk. No association between exposure to styrene and lung cancer risk was found. In conclusion, we cannot exclude a weak association between occupational exposure to vinyl chloride and lung cancer risk. Exposure to acrylonitrile was associated in our study with risk of lung cancer. Exposure to styrene does not seem to increase lung cancer risk., (Copyright 2004 Kluwer Academic Publishers)