Abstract:
:The effect of whole body ionising radiation from a linear accelerator on rat tissue O6-methylguanine (O6-meG) methyltransferase (MT) activity has been assessed using an assay which measures the transfer of 3H-radioactivity from 3H-methylated substrate DNA to protein. The maximal effect occurred 2 days after a 1 krad dose, at which time activity in liver extracts was increased approximately 5-fold in two different rat strains. Activity in lung and kidney was increased approximately 4- and 2-fold, respectively. Similar degrees of enhancement were found in these three tissues using an h.p.l.c. method for measuring MT activity. The increase in activity was reflected in an increased capacity to repair O6-meG produced in liver DNA by administration of [14C]dimethylnitrosamine (DMN): this effect was dose dependent, being detectable after 30 rads and maximal after 600 rads. Incorporation of labelled breakdown products of the DMN into adenine in DNA increased as the dose radiation increased suggesting an inhibition of DNA synthesis. The implications of these results for the mechanism of enhancing O6-meG repair are discussed.
journal_name
Carcinogenesisjournal_title
Carcinogenesisauthors
Margison GP,Butler J,Hoey Bdoi
10.1093/carcin/6.12.1699subject
Has Abstractpub_date
1985-12-01 00:00:00pages
1699-702issue
12eissn
0143-3334issn
1460-2180journal_volume
6pub_type
杂志文章相关文献
CARCINOGENESIS文献大全abstract::The urinary excretion of dimethylnitrosamine (DMN) was studied in male Sprague-Dawley rats. Animals were given DMN (3, 5, 10, 20, 30 and 50 mg/kg body weight, i.p.) or [3H]DMN (0.1, 1 and 3 mg; 8.7, 1.5 and 0.28 mCi/kg body weight, respectively, i.p.) diluted with sterile 0.9% NaCl. Urine was collected for 24 h after ...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/2.7.609
更新日期:1981-01-01 00:00:00
abstract::Docosahexaenoic acid (DHA), a 22:6 n-3 polyunsaturated fatty acid, is the longest and most highly unsaturated fatty acid found in most membranes and has been shown to inhibit cancer cell growth in part by modifying cell signaling. In the current study, alterations to epidermal growth factor receptor (EGFR) signaling u...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgq111
更新日期:2010-09-01 00:00:00
abstract::An elevation in total MAP kinase activity and expression has been observed in breast cancer tissue. However, the mechanisms underlying these changes in kinase activity and regulation by growth factors are not well characterized. In these studies, the effect of the potent mammary mitogen, epidermal growth factor (EGF),...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/20.7.1201
更新日期:1999-07-01 00:00:00
abstract::The reason for different phosphorylation of topoisomerase I in two sublines of L5178Y murine lymphoma (LY cells) was investigated. Camptothecin-resistant LY-S cells show increased poly(ADP-ribose) level and lowered topoisomerase I phosphorylation compared to camptothecin-sensitive LY-R cells. In this study diminished ...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/17.3.383
更新日期:1996-03-01 00:00:00
abstract::Both dehydroepiandrosterone (DHEA) and the synthetic steroid 16 alpha-Br-epiandrosterone (Br-Epi), a more potent inhibitor of glucose-6-phosphate dehydrogenase (G6PDH) than DHEA, inhibit the 12-O-tetradecanoylphorbol-13-acetate (TPA) stimulation of superoxide anion (O2-) formation by human neutrophils. DHEA has previo...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/6.3.333
更新日期:1985-03-01 00:00:00
abstract::Despite significant research, our understanding of the molecular mechanisms of Human Papilloma Virus (HPV) induced cancers remains incomplete. Majority of invasive cervical cancers are caused by high-risk HPV 16 and 18. Two potent HPV oncoproteins, E6 and E7, promote human malignancies by disrupting the activities of ...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgu104
更新日期:2014-08-01 00:00:00
abstract::Alcohol is a major risk factor for oesophageal squamous cell carcinoma (OSCC), the most prevalent histological subtype of oesophageal cancer (OC) worldwide. The metabolism of alcohol is regulated by specific enzymes whose activity and expression is influenced by genetic polymorphisms. We conducted a systematic review ...
journal_title:Carcinogenesis
pub_type: 杂志文章,评审
doi:10.1093/carcin/bgx067
更新日期:2017-09-01 00:00:00
abstract::Epidemiological evidence suggests that the presence of human papillomaviruses (HPV), when combined with smoking behaviors, considerably enhances the risk of developing oral, cervical, vulvar, and/or anal carcinomas. It is well established that the cytochrome P450 (CYP), microsomal epoxide hydrolase (mEH), and other bi...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/16.6.1391
更新日期:1995-06-01 00:00:00
abstract::Several purified polychlorinated biphenyl (PCB) congeners with differing toxicity/tumor promotional activities in rat liver in vivo were tested for their effects on gap-junctional intercellular communication (GJIC) in cell strains and lines derived from human liver and skin. This in vitro assay is being developed to d...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/11.6.921
更新日期:1990-06-01 00:00:00
abstract::IARC Monographs are globally-recognized assessments of carcinogenicity published by International Agency for Research on Cancer and directed to national authorities as a contribution to public health. Currently, though not constraining the scope of studies examined, Monographs are declared to involve only hazard ident...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgaa129
更新日期:2020-12-01 00:00:00
abstract::Dietary-related indoles, isothiocyanates, and the allyl isothiocyanate glucosinolate, sinigrin, were administered to F344 rats in the diet for 2 weeks (chronic protocol) or by gavage 2 h before sacrifice (acute protocol) and the effects of these pretreatments on the alpha-hydroxylation of two carcinogenic nitrosamines...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/6.4.539
更新日期:1985-04-01 00:00:00
abstract::Chemopreventive agents are compounds that inhibit carcinogenesis when administered prior or subsequent to a course of carcinogen administration. The effects of dietary administration of crocin dyes on the hepatic damage induced by aflatoxin B1 (AFB1) and dimethylnitrosamine (DMN) in rats were investigated. Female Spra...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/7.4.595
更新日期:1986-04-01 00:00:00
abstract::In Saccharomyces cerevisiae a number of chemical agents induce synthesis of cytochrome P450. A cytochrome P450 gene has been well characterized in this yeast: CYP51, which codes for a constitutive enzyme involved in the 14 alpha-demethylation of lanosterol, a key step in the biosynthesis of ergosterol. In this work, w...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/13.11.2175
更新日期:1992-11-01 00:00:00
abstract::In Thailand, smoking of commercial cigarettes and of handmade cigarettes has drastically increased in recent decades. Cancer of the lung and of the upper aero-digestive tract have also increased in Thailand as they have in many other countries. It is our working hypothesis that the increase of primary cancer of the li...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/20.1.133
更新日期:1999-01-01 00:00:00
abstract::The methylation status of the rat gamma-glutamyl transpeptidase (GGT) gene was investigated during liver development and hepatocarcinogenesis. The analysis with the restriction enzymes MspI/HpaII revealed that, during ontogeny, there is a progressive methylation of the GGT gene that coincides with a progressive decrea...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/12.6.1035
更新日期:1991-06-01 00:00:00
abstract::We have shown that parathyroid hormone-related protein (PTHrP) is a survival factor for human renal cell carcinoma (RCC) and that its expression is negatively regulated by the von Hippel-Lindau (VHL) tumor suppressor gene at the level of messenger RNA (mRNA) stability, as observed for tumor growth factors (TGFs). Our ...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgn275
更新日期:2009-03-01 00:00:00
abstract::This study presents the physical characterization of mutants induced in mammalian cells by high linear energy transfer alpha-particle radiation that simulates exposure to radon daughters. Alpha-Particles from accelerated 4He at 150 keV/microns were used to induce 20 Chinese hamster ovary mutants that are deficient in ...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/16.8.1981
更新日期:1995-08-01 00:00:00
abstract::In vitro activation of benzo[a]pyrene to protein-binding forms was investigated with the following two systems: (1) various fractions of human and rat blood had a potential of activating benzo[a]pyrene to forms binding to proteins in the presence of linoleic or arachidonic acid. Red blood cells activated much more ben...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/7.2.267
更新日期:1986-02-01 00:00:00
abstract::Phorbol ester-sensitive EL4 murine thymoma cells respond to phorbol 12-myristate 13-acetate with activation of ERK mitogen-activated protein kinases, synthesis of interleukin-2, and death, whereas phorbol ester-resistant variants of this cell line do not exhibit these responses. Additional aspects of the resistant phe...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/18.9.1817
更新日期:1997-09-01 00:00:00
abstract::The effect of co-administration of diethylnitrosamine (DEN) and Clophen A 50, a commercial mixture of polychlorinated biphenyls (PCB), on pre-neoplastic enzyme-altered islands in livers of female Sprague-Dawley rats was studied. The islands were identified by the loss of adenosine-5'-triphosphatase (ATPase), emergence...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/7.10.1697
更新日期:1986-10-01 00:00:00
abstract::Monoclonal or affinity-purified antibodies specific to Novikoff hepatoma cytokeratin p39 were employed to study the origin and fate of p39-containing cell types during hepatocarcinogenesis induced with N,N-dimethyl-p(m-tolylazo)aniline. Frozen sections were obtained from the livers of animals autopsied temporally duri...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/6.8.1147
更新日期:1985-08-01 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::Sulindac, a widely used non-steroidal anti-inflammatory drug (NSAID), has been shown to inhibit chemically induced carcinogenesis in animal models. In the present study, we have investigated the molecular mechanism by which sulindac affects the activity and expression of the enzymes that mediate the initial detoxifica...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgi359
更新日期:2006-08-01 00:00:00
abstract::Reduced retinyl ester synthesis has been associated with several forms of cancer; we therefore proposed studying melanoma development from the perspective of this biochemical pathway. Cultures of human melanoma cells with fibroblastoid morphology showed negligible retinyl ester synthesis; in sharp contrast, those with...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/23.11.1821
更新日期:2002-11-01 00:00:00
abstract::Primary hepatocyte cultures from six human donors were established and their abilities to metabolize the polycyclic aromatic hydrocarbon carcinogen benzo[a]pyrene (B[a]P) were examined. Cells from each donor were plated at similar densities (1 X 10(7) cells/100 mm dish). All cultures metabolized B[a]P to a significant...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/5.12.1577
更新日期:1984-12-01 00:00:00
abstract::The present study was conducted to clarify the cooperative significance of epigenomic and genomic abnormalities during gastric carcinogenesis. Using 21 samples of normal control gastric mucosa (C), 109 samples of non-cancerous gastric mucosa (N) and 105 samples of cancerous tissue (T) from 109 patients with primary ga...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/bgaa079
更新日期:2020-11-13 00:00:00
abstract::An electron microscope study was carried out on changes in the pancreatic acinar tissues of male Syrian hamsters during the course of induction of pancreatic neoplasia by lifetime weekly injections of N-nitroso-bis(2-hydroxypropyl)amine (BHP). The dominant process observed was a loss of differentiation of the acinar c...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/3.5.485
更新日期:1982-01-01 00:00:00
abstract::The metabolism of the carcinogenic pentacyclic azaaromatic compound, dibenz[a,j]acridine, has been examined in liver microsomal incubations using preparations from 3-methylcholanthrene-pretreated Wistar rats. Using authentic synthetic standards, u.v. spectroscopy and mass spectrometry, the following were proved to be ...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/7.8.1371
更新日期:1986-08-01 00:00:00
abstract::Arsenicals are epidemiologically significant chemicals in relation to induction of urinary bladder cancer in man. In the present study, we investigated the dose-dependent promotion potential of dimethylarsinic acid (DMA), a major metabolite of inorganic arsenicals in mammals, for rat urinary bladder carcinogenesis. In...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/17.11.2435
更新日期:1996-11-01 00:00:00
abstract::Inbred strains of mice with differential response to known tumor promoters were compared with respect to their susceptibility to modulation of hepatic antioxidant enzymes by long-term treatment with high fat diet (HF) and phenobarbital (PB). Mice of the C57BL/6J (C57), C3H/HeOuJ (C3H) and DBA/2J (DBA) strains were fed...
journal_title:Carcinogenesis
pub_type: 杂志文章
doi:10.1093/carcin/14.6.1225
更新日期:1993-06-01 00:00:00