Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0005684 (bladder cancer)
 16,431 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Urine was collected from 33 patients resident at the Welsh Spinal Injuries Unit and analysed for volatile N-nitrosamines by gas chromatography. N-nitrosodime-thylamine, N-nitrosopiperidine or N-nitrosopyrrolidine was detected in 32 of the samples. Thirty-one of the samples were infected by one or more microbial species. Nitrate and N-nitrosamines were not found in the sterile urines of a group of 10 control individuals exposed to the same dietary and environmental influences as the spinal patients. Although N-nitrosamines were found in some of the catheter drainage system products, they did not elute into urine on 24-h exposure. In addition, 6 of the nitrosamine-containing urines had no contact with drainage systems as they were collected from spinal patients who were capable of independent voiding. It was concluded that the nitrosamines detected in the urines arose from the bacterial nitrosation of urinary amines. These results support the hypothesis that chronic urinary tract infection may have a role in the aetiology of bladder cancer in spine injured patients.
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PMID:N-nitrosamine generation by urinary tract infections in spine injured patients. 128 39

Humans are exposed to preformed N-nitroso compounds (NOC), but also to a wide range of precursors and nitrosating agents which can react in vivo to form potentially carcinogenic NOC and diazo compounds. Nitrite, nitrate and nitrosating agents can also be synthesized endogenously in enzymic reactions mediated by bacteria, activated macrophages and neutrophils. The latter two cell types generate, via the enzyme nitric oxide synthase, the nitric oxide radical that is involved in cytotoxicity, and is believed to be involved in formation of carcinogenic nitrosamines, DNA base deamination and oxidative damage. Thus endogenous NOC formation, DNA damage and gene mutations in humans could occur at various sites of the body such as the stomach and chronically infected or inflamed organs. Sensitive procedures to estimate the exposure of humans to NOC have been developed and applied in ecological and cross-sectional studies. These have shown that inhabitants of high-risk areas for stomach and esophageal cancer, patients with urinary tract infections (at risk for bladder cancer) and Thai subjects infected with liver fluke (at risk for cholangiocarcinoma) had significantly higher exposure to endogenous NOC. Clinical studies have examined the model of stomach carcinogenesis based on intragastric nitrosation, but the precise roles of bacterial overgrowth and of Helicobacter pylori infection in NOC synthesis and/or inducing oxidative stress in stomach mucosa remain to be clarified. Together these results support the role of NOC and other nitrite-derived mutagens in human cancer etiology, in particular when exposure starts early in life and persists over a long period.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Endogenously formed N-nitroso compounds and nitrosating agents in human cancer etiology. 133 85

The expression of two cell proliferation indices, the proliferating cell nuclear antigen (PCNA), using the monoclonal antibody PC-10 in the immunoperoxidase method, and the nucleolar organizer regions (NORs), using the colloid silver nitrate staining technique, was assessed in formalin-fixed paraffin-embedded material of 50 transitional cell urinary bladder carcinomas. A relationship was found between the histologic grade and each of the two indices used. A significant difference was observed, particularly between carcinomas of grade II and III (p < 0.001). A relationship was also demonstrated between each of PC-10 and AgNOR scores and the clinical stage, but it was attributed mostly to the close correlation of the latter with the histologic grade of these tumors. The linear correlation coefficient between PC-10 and AgNOR scores was 0.757 (p < 0.001). Our results suggest that PC-10 and AgNOR scores may be important prognostic indices in urinary bladder cancer.
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PMID:Comparative assessment of proliferating cell nuclear antigen immunostaining and of nucleolar organizer region staining in transitional cell carcinomas of the urinary bladder. Correlation with other conventional prognostic pathologic parameters. 136 36

An increased risk of bladder cancer is a recognized complication in spine-injured patients undergoing long-term urethral catheterization to preserve renal function. Aerobic cultures from 28 of 30 paraplegic patients showed complex bacterial flora containing nitrate-reducing organisms (Escherichia coli, Proteus and Klebsiella spp.). Urine samples from 29 paraplegic patients were also found to contain volatile nitrosamines. Mean N-nitrosamine excretion levels were 0.65 +/- 0.69 micrograms/day N-nitrosodimethylamine, 0.25 +/- 0.44 micrograms/day N-nitrosopiperidine and 0.39 +/- 0.50 micrograms/day N-nitrosopyrrolidine. A mean urinary nitrite excretion of 10.4 +/- 13.2 mg/day was found in 24 out of 30 paraplegic patients. In the sterile urine of control volunteers (medical staff attending the paraplegic patients and in-patients from other wards of the hospital), no urinary excretion of volatile N-nitrosamines and nitrite was found. The results clearly demonstrate a bacterially mediated in vivo formation of N-nitroso compounds in the urinary tracts of paraplegic patients which may be an important etiological risk factor for bladder cancer in this patient group.
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PMID:Increased urinary nitrosamine excretion in paraplegic patients. 202 61

Urinary nitrite, a precursor of carcinogenic nitrosamines, and nitrate were measured in 73 Japanese patients with urinary tract infections (UTI) and in two control groups. Nitrite was detected in 12% of patients with uncomplicated UTI (226 +/- 161 mumol/l) and in 42% of those with complicated UTI (375 +/- 297 mumol/l). None of the subjects in the control groups excreted detectable amounts of nitrite. The excretion of nitrite in four out of five nitrite excretors continued for at least 14-55 days. The concentrations of urinary nitrite were significantly correlated with those of nitrate- plus nitrite-nitrogen, which reflect dietary nitrate ingestion. The results suggest the importance of close monitoring of nitrite excretor group in UTI patients, to clarify the mechanism of the association between UTI and bladder cancer.
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PMID:Urinary nitrite in Japanese patients with urinary tract infections. 276 99

Saliva and 24-h urine samples were collected from male Schistosomiasis (bilharzia) patients with S. haematobium infection and possible concurrent S. mansoni infection without diagnosed bladder cancer (n = 27), bilharzia patients with diagnosed bladder cancer (n = 23) as well as a comparative control group (n = 27) of healthy Egyptian volunteers with no current bilharzia infection and/or bacterial urinary tract infections from the Nile Delta area of Egypt. Saliva samples were analysed for the presence of nitrate and nitrite; urine samples were analysed for the presence of nitrate, nitrite, volatile and non-volatile N-nitroso compounds. Bilharzia patients prior to, and after, diagnosed bladder cancer regularly excreted free nitrite as well as volatile nitrosamines (N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosopiperidine and N-nitrosopyrrolidine) in addition to which elevated concentrations of non-volatile N-nitrosamino acids (N-nitrosoproline, N-nitrososarcosine, N-nitrosothiazolidine-4-carboxylic acid and its 2-methyl derivative) were also present. Total urinary excretion of volatile N-nitroso compounds (0.32 +/- 0.64 micrograms/day; mean +/- SD) and non-volatile N-nitroso compounds (31.20 +/- 22.07 micrograms/day) was observed in the Egyptian control group. Significantly higher concentrations were found in bilharzia patients: 3.47 +/- 6.42 (P less than 0.05) and 62.91 +/- 21.96 (P less than 0.05); as well as in bilharzia patients with diagnosed bladder cancer: 1.71 +/- 1.96 (P less than 0.02) and 44.94 +/- 7.31 respectively. Free nitrite was found in the urine of two volunteers in the Egyptian control group (1.7 and 3.0 micrograms/day), urinary nitrite was significantly increased in bilharzia patients (5.18 +/- 9.11 micrograms/day, P less than 0.02) and in bladder cancer patients (1.75 +/- 2.81 micrograms/day, P less than 0.05). Nitrate concentrations were elevated from 139.3 +/- 82.2 in the control group to 143.6 +/- 136.3 and 175 +/- 190 in the bilharzia and bladder cancer groups respectively. These results indicate that significant in vivo formation of nitrite and volatile N-nitroso compounds occurs in the urinary bladder of bilharzia patients and this may be an oetiological factor in the induction of bilharzial bladder cancer associated with S. haematobium infection.
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PMID:Urinary excretion of nitrate, nitrite and N-nitroso compounds in Schistosomiasis and bilharzia bladder cancer patients. 292 99

Levels of urinary mutagens, thioethers, N-nitrosamino acids, nitrate, nicotine, cotinine and creatinine were measured in 21 non-smokers, 26 smokers of blond tobacco, 9 smokers of black tobacco and 5 smokers of both types of tobacco, all eating a similar diet. Results were expressed either per 24 h urine or per mmol creatinine. The sum of urinary nicotine and cotinine levels (N + C) was used as a measure of exposure to the number of cigarettes smoked. Statistically significant positive dose-effect relationships were obtained between the urinary N + C levels and (i) the number of revertants (Salmonella typhimurium TA98, with a metabolic activation system); (ii) the concentration of thioethers; (iii) the levels of N-nitrosoproline or the sum of all nitrosamino acids excreted and (iv) the amount of urinary nitrate. No such correlation was found between N + C levels and induction potency in the SOS chromotest. A linear dose-effect relationship between urinary mutagenicity (i.e. log revertants of S. typhimurium TA98) and N + C levels or number of cigarettes per day was established for smokers of blond tobacco. After adjustment for N + C levels, the urine of smokers of black tobacco contained twice as much mutagenic material as did the urine of blond tobacco smokers (P = 0.02). For other exposure markers, no statistically significant difference was found between the two types of smokers. Epidemiological studies have shown that the risk of urinary bladder cancer is 2.5 times higher in smokers of black tobacco than in blond tobacco. Therefore, our findings on urinary mutagenicity provide experimental evidence that the type of tobacco is the factor responsible for the observed difference in risk and that smoking of black as compared to blond tobacco results in a higher exposure of the urinary bladder to genotoxic hence potentially carcinogenic substances.
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PMID:Levels of mutagens in the urine of smokers of black and blond tobacco correlate with their risk of bladder cancer. 292 2

Urine samples from 31 patients with urinary-tract infections and from 31 controls were analysed for volatile nitrosamines, N-nitrosamino acids, total N-nitroso compounds as a group, and nitrite/nitrate. The concentration of N-nitrosodimethylamine was significantly elevated in urines infected with Escherichia coli, Proteus mirabilis and Klebsiella pneumoniae. The levels of nitrite, N-nitrosoproline and total N-nitroso compounds, when expressed as the amount per mol creatinine, were also significantly increased in patients with bacteriuria. Several bacterial strains were capable of catalysing nitrosation of morpholine at neutral pH. These results suggest that N-nitroso compounds can be formed in vivo in the infected bladder, which could explain the association between urinary-tract infections and increased risk for bladder cancer.
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PMID:N-nitrosamine formation in urinary-tract infections. 367 7

In Egypt, bladder cancer incidence is high in areas where the prevalence and intensity of Schistosoma haematobium infection is also high. Experimental evidence shows bladder carcinogenesis to be a multi-stage process which can be accelerated by many factors. N-nitroso compounds, some of which are known bladder carcinogens, can be formed from amine precursors and nitrate in urine during some bacterial infections. In experimental animals the growth of nitrosamine-induced urothelial cancers is accelerated by damage to the urothelium caused by S. haematobium infections, and by analogy in man this could account for the lower peak age of incidence of this cancer in Egypt by comparison with Europe. The present study was designed to investigate whether bacterial infection of the urinary tract was common in areas of endemic schistosomiasis and whether N-nitrosamines were regularly found to be associated with bacteriuria. Urine samples from young men in the Qalyub area of Egypt and from an adjacent Delta region were analysed for S. haematobium ova, the nature and intensity of any bacterial infection, nitrate and nitrite, and total N-nitroso compounds plus volatile N-nitrosamines. A relatively high prevalence of bacteriuria was found in young men with schistosomiasis and low levels of N-nitroso compounds were present in all specimens. When the groups were sub-divided on the basis of the ability of their bacterial flora to reduce nitrate to nitrite (the latter is required for the nitrosation of amine precursors to N-nitroso compounds), significantly higher levels of N-nitroso compounds were found in S. haematobium-infected individuals also infected with nitrate-reducing bacteria by comparison either with uninfected controls (p less than 0.0005) or with those infected with non-nitrate-reducing bacteria (p less than 0.001). The results show N-nitroso compounds to be present in the urines of young men in areas of endemic S. haematobium infection in Egypt, and elevated levels of urinary N-nitroso compounds to be associated with infection of the urinary tract by various species of nitrate-reducing bacteria.
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PMID:Association of bacteriuria and urinary nitrosamine formation with Schistosoma haematobium infection in the Qalyub area of Egypt. 692 71

In a Canadian population-based case-control study of 480 males and 152 female case-control pairs, the relative risk for development of bladder cancer for ever used versus never used cigarettes was 3.9 for males and 2.4 for females, with a dose-response relationship in both sexes. A reduced risk was associated with the use of filter cigarettes compared to nonfilter cigarettes. After control for cigarette usage, a significant risk was noted for male pipe smokers. For male ex-smokers the risk after 15 years of no smoking was less than one-half that of current male smokers. Bladder cancer risk was found for workers in the chemical, rubber, photographic, petroleum, medical, and food processing industries among males and for workers occupationally exposed to dust or fumes among both sexes. Bladder cancer risk was elevated for males consuming all types of coffee, regular coffee, and instant coffee and for females consuming instant coffee, but no dose-response relationship was found. Risk was found for males consuming water from nonpublic supples but not for females. No risk was observed in males or females consuming nitrate-containing foods, beverages other than coffee, or fiddlehead greens. Hair dye usage in females and phenacetin usage in males and females carried no risk. Divergent findings by area for aspirin suggested that an overall association was not causal. Reevaluation of the data on artificial sweeteners confirmed a significant bladder cancer risk in males and a dose-response relationship. The cumulated population attributable risk for bladder cancer was 90% for males from cigarette smoking, industrial exposure, and exposure to nonpublic water supplies and 29% for females from cigarette smoking, industrial exposure, and instant coffee consumption.
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PMID:Tobacco use, occupation, coffee, various nutrients, and bladder cancer. 692 84


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