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

The effects of amino acids on the enhanced agglutinability of bladder cells with concanavalin A induced by subcarcinogenic treatment with N-butyl-N-(4-hydroxybutyl)nitrosamine were examined. The amino acids examined were L-alanine, L-arginine, L-asparagine, L-aspartic acid, L-cysteine, L-glutamic acid, L-glutamine, L-glycine, DL- and L-histidine, L-hydroxyproline, L-isoleucine, D- and L-leucine, L-lysine, L-methionine, DL- and L-phenylalanine, L-proline, L-serine, L-threonine, DL-, D- and L-tryptophan, L-tyrosine and D- and L-valine. They were added to powdered diet at a concentration of 2.0%. L-Leucine, L-isoleucine, L-valine, DL- and D-tryptophan prolonged the period during which the bladder cells showed enhanced agglutinability with concanavalin A. Leupeptin, a protease inhibitor, and L-leucyl-L-leucine were also examined at a concentration of 0.1% because of their similar chemical structures, and were found to have the same effect. The tumor-promoting effects of DL-tryptophan and leupeptin have already been established by in vivo carcinogenesis experiments. The effects of L-leucine, L-isoleucine, L-valine, D-tryptophan and L-leucyl-L-leucine, detected by this short term assay, suggest that these compounds may also be promoters of bladder cancer in rats.
 ...
PMID:Detection of amino acids as possible promoters of bladder cancer in rats by measuring their enhancement of agglutination of bladder cells by concanavalin A. 716 May 80

Aromatic amines have been implicated in the etiology of bladder cancer in humans since Rehn observed the disease in 3 workers in the German aniline dye industry in 1895. 2-Naphthylamine was identified 40 years later as one of the carcinogens in tests involving the feeding of the chemical to dogs. The discovery of N-2-fluorenylacetamide as a carcinogen in rodents inducing tumors of the bladder and other organs provided a more inexpensive and rapid model for the study of bladder carcinogenesis. The metabolic activation pathways of aromatic amine and amide compounds has been extensively examined. In the 1960's, organ-specific rodent models were discovered with the use of N-butyl-N-(4-hydroxybutyl) nitrosamine, N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide, or N-methyl-N-nitrosourea. Recent experiments have demonstrated that bladder carcinogenesis can be divided into two stages similar to the initiation-promotion model in mouse skin. Possible promoters have included sodium saccharin, sodium cyclamate, and tryptophan. Certain metabolites of the latter compound are also N-substituted aryl compounds. Lastly, recent studies of the relationship of urine to the carcinogenic process in the bladder indicate that it can act as a promoting agent as well as a carrier of carcinogenic substances.
 ...
PMID:Urinary bladder carcinogenesis with N-substituted aryl compounds: initiation and promotion. 734 85

We developed a new method to measure quinoline compounds including kynurenic acid, xanthurenic acid, and the 8-methyl ether of xanthurenic acid in the urine. The excretion of quinoline compounds in 33 patients with bladder cancer was investigated. Abnormal excretion of the 8-methyl ether of xanthurenic acid was confirmed in 13 patients. There were significant increases in the excretion of kynurenic acid and the 8-methyl ether of xanthurenic acid in males and of xanthurenic acid in females. After a L-tryptophan load, the excretion of all three derivatives was increased in males and kynurenic acid excretion was increased in females.
 ...
PMID:A new method to determine urinary quinoline compounds in patients with bladder cancer. 735 5

Several epidemiological, clinical and experimental studies have been carried out to determine whether there is an aetiological role for schistosomiasis in the multi-stage process of bladder carcinogenesis. Lines of evidence supporting the association between bladder cancer and schistosomiasis include indications from the geographical correlation between the two conditions, the distinctive patterns of gender and age at diagnosis, the clinicopathological identity of schistosome-associated bladder cancer and the extensive experimental evidence in infected laboratory animals. Although the causative role of schistosomiasis is now accepted, various associated factors have been proposed in the induction of this particular type of cancer. While all may contribute to the carcinogenic process taking place in the infected bladder, none of these has yet been confirmed. Most attention has been directed at theories proposing possible roles for urinary chemical carcinogens, particularly tryptophan metabolites, N-nitroso compounds and of beta-glucuronidase, as factors that are primarily involved in the initiation of bladder carcinogenesis in areas endemic for schistosomiasis.
 ...
PMID:Role of schistosomiasis in human bladder cancer: evidence of association, aetiological factors, and basic mechanisms of carcinogenesis. 772 97

In a controlled trial a gynecological history has been studied for 154 females with bladder tumors against 213 matched women without the tumor. The risk to develop the tumor was found to rise with the history of a short reproductive period, abortions, primary infertility, cancer of the corpus uteri and of the breast, ovarian cysts. Tryptophan metabolism assessed in 242 and 541 women and men with bladder cancer and free of it, respectively, was indicative of more frequent urinary registration of carcinogenic tryptophan metabolite 3-oxyantranilic acid: for females 40.5 per 100 in case of cancer, 10 per 100 in healthy ones; for males with cancer 33.9, without cancer 7.4 per 100 examinees. Radioimmunoassays of hormone concentrations in the serum with correlation to tryptophan metabolism for 55 cancer and 49 healthy females showed lowered levels of progesterone, folitropin and lutropine to occur more often in cancer women with urinary 3-oxyantranilic acid. The above endogenic factors analyzed retrospectively suggest involvement of hormonal status alterations in bladder cancer onset.
 ...
PMID:[The characteristics of the hormonal status in women with bladder neoplasms]. 794 Nov 16

In tryptophan metabolites, 3-hydroxykynurenine and 3-hydroxyanthranilic acid have been reported to show a carcinogenic action to mice bladder and the relation of the metabolites to human bladder cancer has been discussed. We developed methods for the fluorometric assay of these compounds and showed that the excretion of 3-hydroxyanthranilic acid increased in the patients with bladder cancer. We also devised methods for the fluorometric assay of glucuronide and sulfate of 3-hydroxyanthranilic acid and showed that the minor excretion of these conjugated forms was shown in humans. The distribution of these compounds was also studied and the obtained data suggests that 3-hydroxykynurenine has affinity for the pancreas. We then developed methods for the determination of other metabolites of tryptophan. A fluorescence reaction with UV irradiation was found and applied to the determination. This method is the most sensitive to kynurenic acid but can be applied to kynurenine, nicotinamide and quinolinic acid. Furthermore, this methods also applied to the determination of some medicines, e.g. indomethacin, isoniazid, nalidixic acid, nicorandil and disodium cromoglicate in the serum or urine. We further devised other methods for the determination of xanthurenic acid and 5-hydroxyindoles.
 ...
PMID:[Microanalysis of tryptophan metabolites]. 941 79

The etiology of bladder cancer is well investigated. Bladder carcinogenicity of nitrosamines is proven in animals but not in men, although dimethylnitrosamine in urine of patients with urinary infections or bilharziosis suggest a causative role. Aromatic amines are strong bladder carcinogens. Arsen is proven to be bladder carcinogenic as well as the nitrofurane FANFT. Nitrofurantoin however is not bladder carcinogenic nor are the endogenous metabolites of tryptophan. The influence of papilloma virus on bladder carcinoma induction ist not definitely proven yet. Bilharziosis or chronic urinary infections correlate with bladder carcinomas, nitrosamines being the possible reason. The reason for the increased incidence of bladder carcinomas in balkan nephropathy ist not clear. Arcolein as a metabolite of Cyclophosphamid is a strong bladder carcinogen as well as Phenacetin. Immune suppression and radiotherapy are risk factors, too. About 50% of bladder carcinomas are due to cigaret smoking.
 ...
PMID:[Etiopathology, risk factors, environmental influences and epidemiology of bladder cancer]. 1176 Mar 47

We developed methods for the fluorometric assay of 3-hydroxykynurenine and 3-hydroxy-anthranilic acid, which are suspected as carcinogens in bladder cancer. It was shown that the urinary excretion of 3-hydroxyanthranilic acid increased in patients with bladder cancer. We also developed methods for the fluorometric assay of glucuronide and sulfate of 3-hydroxyanthranilic acid and showed that the excretion of these conjugated forms was minor in humans. The distribution of 3-hydroxykynurenine was studied and data obtained suggested that it has an affinity for the pancreas. We then developed methods for determination of the related compounds of tryptophan. Fluorescence reaction with UV radiation was applied to the determinations of kynurenic acid, kynurenine, quinolinic acid, nicotinic acid, nicotinamide, N1-methyl-nicotinamide, isatin, xanthrenic acid, and melatonin in the serum or urine. Furthermore, the fluorescence reaction with UV radiation was applied to some drugs, e.g., indomethacin, isoniazid, naldixic acid, nicorandil, and disodium cromoglycate. The relationship was investigated between the tumor promoter, 12-tetradecanoyl-phobol-13-acetate (TPA), and delayed hypersensitivity in mice. The foot pad reaction (FPR) in mice was suppressed by the application of TPA following the application of 7,12-dimethylbenz[alpha]-anthracene (DMBA), a tumor initiator, in BALB/c mice, while the FPR was suppressed by the application of TPA alone in C3H/He mice. CD8+ and CD4+ T cells, which suppress the FPR, were induced in BALB/c and C3H/He mice, respectively. These T cells produced soluble factors that inhibited the FPR in mice.
 ...
PMID:[Microanalysis of tryptophan metabolites and suppressor factor of delayed-type hypersensitivity in mice]. 1213 39

In fiscal 1974 and fiscal 1975, $650000 will be spent on contracts for studies of birth control methods and their relationship to birth defects. The effect of oral contraceptives (OCs) on various nutrients is among top interest. It has been shown that OCs increase blood levels of Vitamin-A, copper and iron while they decrease folic acid, zinc and Vitamin-B12 and B6. The decrease of Vitamin-B6 interfers with the tryptophan mechanism and affects glucose tolerance as well as neurotransmitters which can be directly related to reports of depression and a higher rate of bladder cancer. A question arose as to whether dietary supplements would counteract the nutritional depletion. The group of unanswered questions was summed up by a question: "So, the question is, is it the pill or the pill user?"
 ...
PMID:Effects of OCs on various nutrients is among top priority research areas. 1225 42

The carcinogenic risk of aromatic amines in humans was first discovered when a physician related the occurrence of urinary bladder cancer to the occupation of his patients. They were employed in the dyestuff industry, chronically exposed to large amounts of intermediate arylamines. Laboratory investigations disclosed that rats and mice administered specific azo dyes arylamines or derivatives developed cancer, primarily in the liver. Also, at that time, a possible pesticide, 2-aminofluorene, was tested for chronic toxicity, revealing that it rapidly induced cancers in several organs of rodents. This led to investigations on the mode of action of this class of chemicals, including their metabolic conversion. Biochemical activation to more reactive N-hydroxy compounds was found to occur, mostly in the liver, through what is now known as the cytochrome p450 enzyme systems, and also through prostaglandin synthetases. There were species differences. Guinea pigs were resistant to carcinogenesis because of the low titer of the necessary activating enzymes. In target tissues, a second essential reaction was necessary, namely acylation or sulfate ester formation. The reactive compounds produced display attributes of genotoxicity in appropriate test systems. Interest in this class of compounds increased when of Sugimura and colleagues discovered the formation of mutagens at the surface of cooked meat or fish, that were identified as heterocyclic amines (HCAs). These compounds undergo the same type of activation reactions, as do other arylamines. Epidemiological data suggest that meat eaters may have a higher risk of breast and colon cancer. HCAs induced cancer in rats in these organs and also in the prostate and the pancreas. In addition, there is some evidence that they affect the vascular system. The formation of HCAs during cooking can be decreased by natural and synthetic antioxidants, by tryptophan or proline, or by removing the essential creatine through brief microwave cooking prior to frying or broiling. The amounts of HCAs in cooked foods are small, but other components in diet such as omega-6-polyunsaturated oils have powerful promoting effects in target organs of HCAs. On the other hand, the action of HCAs may be decreased by foods containing antioxidants, such as vegetables, soy, and tea. Some constituents in foods also induce phase II enzymes that detoxify reactive HCA metabolites. Additional mechanisms involved decreased growth of neoplasms by intake of protective foods. Possibly, the carcinogenic effect of HCAs is accompanied by the presence of reactive oxygen species (ROS), which are also inhibited by antioxidants. World-wide, there have been many contributors to knowledge in this field. Adequate information may permit now to adjust lifestyle and lower the risk of human disease stemming from this entire class of aryl and HCA.
 ...
PMID:Comments on the history and importance of aromatic and heterocyclic amines in public health. 1235 Nov 40


<< Previous 1 2 3 4 5 6 Next >>