Abstract:
:The possibility that ascorbic acid, as a nucleophile, may inhibit mutagenicity induced by electrophilic metabolites of N-nitroso compounds was examined. In vitro data are presented to show that ascorbic acid does not decrease the mutagenicity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in a modified Ames bacterial mutagenicity system if deionized water is used to prepare the incubation medium. However, ascorbic acid prevents the mutagenicity of MNNG in vitro if added to bacteria in a medium prepared with either sterile tap water or deionized water and Cu2+ ions and that this antimutagenic response is blocked by EDTA. Additional in vitro experiments suggest that when ascorbic acid and Cu2+ ions are mixed in aqueous solution, H2O2 and free radicals derived from H2O2 are formed and these compounds may deactivate N-nitroso compounds. In vivo data are presented to show that ascorbic acid supplementation to guinea pigs (2000 mg/kg body weight/day) has no effect on the mutagenicity of N-nitrosodimethylamine, MNNG, N-methylnitrosourea and streptozotocin using the intrahepatic host-mediated bacterial mutagenicity assay. Additional in vivo studies demonstrate that simultaneous oral administration of ascorbic acid prevents the mutagenicity that follows the intragastric nitrosation of aminopyrine by nitrite while dietary pre-treatment with ascorbic acid does not. These findings suggest that ascorbic acid can block the intragastric formation of mutagenic N-nitroso compounds but that ascorbic acid has no effect on mutagenicity of N-nitroso compounds once they are formed.
journal_name
Carcinogenesisjournal_title
Carcinogenesisauthors
Norkus EP,Kuenzig WAdoi
10.1093/carcin/6.11.1593subject
Has Abstractpub_date
1985-11-01 00:00:00pages
1593-8issue
11eissn
0143-3334issn
1460-2180journal_volume
6pub_type
杂志文章相关文献
CARCINOGENESIS文献大全abstract::The HSP70 family of heat shock proteins consists of molecular chaperones of approximately 70kDa in size that serve critical roles in protein homeostasis. These adenosine triphosphatases unfold misfolded or denatured proteins and can keep these proteins in an unfolded, folding-competent state. They also protect nascent...
journal_title:Carcinogenesis
pub_type: 杂志文章,评审
doi:10.1093/carcin/bgt111
更新日期:2013-06-01 00:00:00
abstract::Cancer-associated fibroblasts (CAFs) tend to have tumor-promoting capacity, and can provide therapeutic targets. Even without cancer cells, CAF phenotypes are stably maintained, and DNA methylation and H3K27me3 changes have been shown to be involved. Here, we searched for a potential therapeutic target in primary CAFs...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgaa131
更新日期:2020-12-07 00:00:00
abstract::In addition to genetic changes, epigenetic aberrations also play important roles in radiation- and chemical-induced disorders and carcinogenesis. The present study investigated whether epigenetic therapy with a histone deacetylase (HDAC) inhibitor has dual benefits for radiation-induced oral mucositis and chemical-ind...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgp079
更新日期:2009-08-01 00:00:00
abstract::Cultured human epidermal cells which require no feeder layer were used to study metabolism of benzo[a]pyrene (BP) and DNA adduct formation. The cultures were prepared from a single cell suspension and maintained at a pH of 5.9--6.2. At 2 microM BP some cell toxicity was observed, and substantial cell death occurred at...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/2.7.581
更新日期:1981-01-01 00:00:00
abstract::The effect of the tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate (TPA) was studied using an immortalized human bronchial epithelial cell line, BEAS-2B, both in vivo and in vitro. The in vivo model consisted of tracheas reconstituted with an epithelium of BEAS-2B cells xenotransplanted into athymic nude mice. Int...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/10.12.2335
更新日期:1989-12-01 00:00:00
abstract::Weanling male F344 rats were fed either a semi-purified diet low in methionine and lacking in choline and folic acid (folate/methyl deficient) or a supplemented control diet for periods of 2, 5, 7 days, 3 weeks, and 9 weeks. Two days after initiating the folate/methyl deficient diet in weanling F344 rats, the incidenc...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/18.2.287
更新日期:1997-02-01 00:00:00
abstract:UNLABELLED:Neurotrophic factors possess an emerging role in the pathophysiology of several gastrointestinal disorders, regulating innervation, pain sensation and disease-associated neuroplasticity. Here, we aimed at characterizing the role of the neurotrophic factor neurturin (NRTN) and its receptor glial-cell-line-der...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgt312
更新日期:2014-01-01 00:00:00
abstract::Chemotherapeutic agents have been the mainstay of cancer therapy for years. However, their effectiveness has been limited by toxicities they impart on normal cells. Staurosporine (ST) has been shown to arrest normal, but not breast cancer, cells in G1. Therefore, ST may become a chemoprotective agent, arresting normal...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgt186
更新日期:2013-10-01 00:00:00
abstract::The effects of D-limonene and citrus fruit oils, i.e. orange oil and lemon oil, on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced neoplasia of the lungs and forestomach of female A/J mice were investigated. D-Limonene and the citrus fruit oils given p.o. 1 h prior to NNK, also administered p.o., inhibite...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/12.1.115
更新日期:1991-01-01 00:00:00
abstract::In the present study the modulating effects of dietary fish oil (MaxEPA) on unsaturated fat-promoted pancreatic carcinogenesis in azaserine-treated rats were investigated. Three groups of 20 rats (each group comprised five saline-treated and 15 azaserine-treated animals) were fed an AIN76-based purified diet containin...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/15.10.2107
更新日期:1994-10-01 00:00:00
abstract::Mouse ovarian surface epithelial cells (MOSEC) were obtained from virgin, mature mice by mild trypsinization and were repeatedly passaged in vitro. Early passage cells (<20 passages) exhibited a cobblestone morphology and contact inhibition of growth. After approximately 20 passages in vitro, cobblestone morphology an...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/21.4.585
更新日期:2000-04-01 00:00:00
abstract::The enzyme O6-methylguanine-DNA methyltransferase repairs alkylation-induced DNA damage, O6-methylguanine and O4-methylthymine, the former being formed more frequently. Previously, by means of gene targeting, we generated mice in which alleles for methyltransferase were disrupted. We now use these mouse lines, which a...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/18.8.1631
更新日期:1997-08-01 00:00:00
abstract::Previous studies from our laboratory demonstrated that diallyl disulfide (DADS), an oil-soluble allyl sulfur compound found in processed garlic, markedly suppressed p34(cdc2) kinase activity and induced a G(2)/M phase arrest in cultured human colon tumor (HCT-15) cells. The present studies reveal that suppression of p...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:
更新日期:2000-06-01 00:00:00
abstract::A hallmark of cancer is aberrant DNA methylation, consisting of global hypomethylation and regional hypermethylation of tumor suppressor genes. DNA methyltransferase inhibitors have been recognized as promising candidate anticancer drugs. Drug development has focused on DNA methylation inhibitors with the goal of acti...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgq221
更新日期:2011-02-01 00:00:00
abstract::Cigarette smoking is a major cause of human cancer at a variety of sites, although its carcinogenic mechanisms remains unestablished. Cigarette smoke can be divided into two phases, gas phase and particulate matter (tar). Both phases contain high concentrations of oxidants and free radicals, especially nitric oxide (N...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/18.7.1359
更新日期:1997-07-01 00:00:00
abstract::Grainyhead-like 2 (GRHL2) is one of the three mammalian homologues of Drosophila Grainyhead involved in epithelial morphogenesis. We recently showed that GRHL2 also controls normal epithelial cell proliferation and differentiation. In this study, we investigated the role of GRHL2 in oral carcinogenesis and the underly...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgw027
更新日期:2016-05-01 00:00:00
abstract::A mouse monoclonal antibody (Mab) was prepared which showed high specificity for a potential marker of exposure to methylating carcinogens such as 3-methyladenine (3-MeAde). In a low-temperature (4 degrees C) ELISA a linear calibration curve was obtained between 3 and 50 fmol/well. In combination with an immunoaffinit...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/11.10.1747
更新日期:1990-10-01 00:00:00
abstract::The ability of cytosolic 3-methylcholanthrene binding proteins from rat liver to interact with DNA was studied using DNA-cellulose chromatography. Two DNA binding fractions, eluting in 0.15 M KCl (peak 1) and 0.33 M KCl (peak 2), were observed on salt elution from a denatured DNA-cellulose column which had been incuba...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/1.6.481
更新日期:1980-06-01 00:00:00
abstract::The role of nitric oxide (NO) in colon cancer remains controversial. Inducible nitric oxide synthase (iNOS) has been reported to be up regulated and down regulated in colorectal cancer in both animal models and patient tissue samples. Cyclooxygenase-2 (COX-2) is important in colorectal carcinogenesis but its relations...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgg014
更新日期:2003-04-01 00:00:00
abstract::The cyclooxygenase-2 (COX-2) inhibitor celecoxib and the ornithine decarboxylase (ODC) inhibitor difluoromethylornithine (DFMO) were each previously shown to prevent skin tumor development when administered throughout the course of UV irradiation. This raised the question of whether maintenance or continued growth of ...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgg046
更新日期:2003-05-01 00:00:00
abstract::The inhibitory effects of three phenolic compounds (ferulic, chlorogenic and ellagic acids) on benzo[a]pyrene- and 7,12-dimethylbenz[a]anthracene-induced neoplasia have been investigated in mice. Ellagic acid was the most potent antagonist of tumorigenesis since this compound is active, by i.p. administration or added...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/4.12.1651
更新日期:1983-12-01 00:00:00
abstract::Cyproterone acetate (CPA), a synthetic steroid hormone widely used as a human pharmaceutical, has recently been shown to induce unscheduled DNA synthesis (UDS) in vitro in primary cultures of rat and human hepatocytes. In the present study CPA was evaluated for its ability to initiate UDS in the liver of female rats i...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/17.10.2271
更新日期:1996-10-01 00:00:00
abstract::Two new mouse epidermal cell lines have been isolated and characterized as target cells for three chemical carcinogens. The ability to grow these cells at low density (approximately 5 clonogenic cells/cm2) has permitted more precise quantitation of chemical carcinogen-induced changes in epidermal differentiation. The ...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/6.9.1245
更新日期:1985-09-01 00:00:00
abstract::It is estimated that one-third of Americans use dietary herbal supplements on a regular basis. Diets rich in bioactive phytochemicals are associated with reduced risk of certain cancers, notably, colon cancer. Herbal supplements have not been directly tested as sources of bioactive cancer preventives. Hence, this stud...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgi089
更新日期:2005-08-01 00:00:00
abstract::Human papillomavirus (HPV) type 16 infection is an etiologic factor in a subset of head and neck squamous cell carcinomas (HNSCC). It is unknown if host genetic susceptibility modifies the HPV16-HNSCC association. DNA samples collected as part of a Boston area case-control study of HNSCC were genotyped for single-nucl...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgp076
更新日期:2009-06-01 00:00:00
abstract::Genomic alterations affecting components of the mechanistic target of rapamycin (mTOR) pathway are found rather frequently in cancers, suggesting that aberrant pathway activity is implicated in oncogenesis of different tumor types. mTOR functions as the core catalytic kinase of two distinct complexes, mTOR complex 1 (...
journal_title:Carcinogenesis
pub_type: 杂志文章,评审
doi:10.1093/carcin/bgy086
更新日期:2018-07-30 00:00:00
abstract::The Raji human lymphoma line is able to remove O6-methylguanine (O6MeG) lesions introduced by treatment of cells with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). The reaction has a rapid phase in which approximately 40% of the O6MeG is removed in the first 10 min. The capacity of cells for rapid O6MeG removal is limi...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/2.12.1293
更新日期:1981-01-01 00:00:00
abstract::Telomeres maintain chromosomal stability and integrity and are crucial in carcinogenesis. Telomere length is implicated in multiple cancer risk, but the results are conflicting. Genome-wide association studies have identified several genetic loci associated with telomere length in Caucasians. However, the roles of tel...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgv075
更新日期:2015-09-01 00:00:00
abstract::The relationship between urinary metabolites and DNA damage in the urinary bladder epithelium of male and female rats was tested by alkaline elution assay after an intravesical injection of OPP or its urinary metabolites. 2-Phenyl-1,4-benzoquinone (PBQ) revealed a weak DNA-damaging activity in both sexes at 0.05-0.1%....
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/10.10.1823
更新日期:1989-10-01 00:00:00
abstract::Long non-coding RNAs (lncRNAs) are regarded as important functional regulators of various biological processes and are also known to be involved in the occurrence and development of human cancers, including breast cancer (BC). In our present study, the RNA expression profiling data for a large cohort of human BC sampl...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgz197
更新日期:2020-09-24 00:00:00