Abstract:
:Caffeine is a model radiosensitizing agent that is thought to work by abrogating the radiation-induced G(2)-phase checkpoint. In this study, we examined the effect that various concentrations of caffeine had on cell cycle checkpoints and apoptosis in cells of a human lung carcinoma cell line and found that a concentration of 0.5 mM caffeine could abrogate the G(2)-phase arrest normally seen after exposure to ionizing radiation. Surprisingly, at a concentration of 5 mM, caffeine not only induced apoptosis by itself and acted synergistically to enhance radiation-induced apoptosis, but also induced a TP53-independent G(1)-phase arrest. Examination of the molecular mechanisms by which caffeine produced these effects revealed that caffeine had opposing effects on different cyclin-dependent kinases. CDK2 activity was suppressed by caffeine, whereas activity of CDC2 was enhanced by suppressing phosphorylation on Tyr15 and by interfering with 14-3-3 binding to CDC25C. These data indicate that the effect of caffeine on cell cycle checkpoints and apoptosis is dependent on dose and that caffeine acts through differential regulation of cyclin-dependent kinase activity.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Qi W,Qiao D,Martinez JDdoi
10.1667/0033-7587(2002)157[0166:citigp]2.0.co;2subject
Has Abstractpub_date
2002-02-01 00:00:00pages
166-74issue
2eissn
0033-7587issn
1938-5404journal_volume
157pub_type
杂志文章abstract::To understand the biophysical mechanism(s) underlying the induction of cell death by the decay of the Auger electron emitter iodine-125 in DNA, Chinese hamster V79 lung fibroblasts were labeled with 5-[(125)I]iodo-2'-deoxyuridine ((125)IdU) for two doubling times and frozen and stored at -135 degrees C in the presence...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/0033-7587(2000)154[0326:todiiq]2.0.co;2
更新日期:2000-09-01 00:00:00
abstract::Telomeres cap the ends of chromosomes, preventing end-to-end fusions and subsequent chromosome instability. Here we used a telomerase knockout model to investigate whether telomerase participates in the processes of DNA break repair by de novo synthesis of telomere repeats at broken chromosome ends (chromosome healing...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr3203
更新日期:2004-08-01 00:00:00
abstract::Neurons are essential components of neural circuits and provide brain function organization. We previously reported that X irradiation induces apoptosis in immature neurons. To the best of our knowledge, there have been few reports investigating the effects of X irradiation on mature neurons. We analyzed the effects o...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR3098.1
更新日期:2013-06-01 00:00:00
abstract::Beagle dogs had signs of restrictive lung disease 1 to 5 years after exposure by inhalation to 239PuO2 aerosols. The 239PuO2 aerosols were monodisperse with activity median aerodynamic diameters of 0.75, 1.5, or 3.0 microns. The plutonium particles produced protracted alpha irradiation of the lungs. Ten dogs had speci...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1988-08-01 00:00:00
abstract::Peroxidation of unconjugated polyunsaturated fatty acids such as linolenic acid proceeds through a free radical chain mechanism and is accompanied by the formation of conjugated dienes such as hydroperoxides. In an investigation of radiation-induced oxidation of aqueous linolenate, we have measured two indexes of pero...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/0033-7587(2000)153[0201:eotfod]2.0.co;2
更新日期:2000-02-01 00:00:00
abstract::The efficacy of photodynamic therapy is dependent upon the optical dose rate or upon the fractionation schedule on the light. These effects are thought to be limited by the time required for oxygen diffusion from the capillaries, since this therapy can consume oxygen faster than it can be supplied to tissues distant f...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.2307/3579621
更新日期:1997-05-01 00:00:00
abstract::The Radiological Research Accelerator Facility (RARAF) is in its 50th year of operation. It was commissioned on April 1, 1967 as a collaboration between the Radiological Research Laboratory (RRL) of Columbia University, and members of the Medical Research Center of Brookhaven National Laboratory (BNL). It was initiall...
journal_title:Radiation research
pub_type: 历史文章,杂志文章
doi:10.1667/RR002CC.1
更新日期:2017-04-01 00:00:00
abstract::The relationship between the intracellular glutathione (GSH) concentration and the aerobic radiation response was studied in Chinese hamster ovary cells. Various degrees of GSH depletion were produced by exposure to buthionine sulfoximine (BSO) and/or diethyl maleate (DEM). Diethyl maleate did not act as a classical r...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1991-03-01 00:00:00
abstract::The relationship of ionizing radiation to the age-related ophthalmological findings of the 1978-1980 ophthalmological examination of A-bomb survivors of Hiroshima and Nagasaki has been reanalyzed using DS86 eye organ dose estimates. The main purpose of this reevaluation was to determine whether age and radiation expos...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1992-09-01 00:00:00
abstract::Hypoadrenocorticism, known as Addison's disease in humans, was diagnosed in six beagles after inhalation of at least 1.7 kBq/g lung of 238PuO2. Histological examination of adrenal gland specimens obtained at necropsy revealed marked adrenal cortical atrophy in all cases. Autoradiographs showed only slight alpha-partic...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1996-12-01 00:00:00
abstract::The immunocytochemical response to DNA damage induced by low-energy bismuth and carbon ions was investigated in normal human fibroblasts. Inside the nuclei, the traversing charged particles lead to the accumulation of proteins related to DNA lesions and repair along the ion trajectories. Irradiation under a standard g...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/0033-7587(2003)159[0676:biohct]2.0.co;2
更新日期:2003-05-01 00:00:00
abstract::The interaction function gamma(chi), which was introduced in the theory of dual radiation action as the probability that two energy transfers separated by distance chi combine with each other to produce a lesion, was estimated with sparsely ionizing radiation (60Co gamma rays and 40 kV X rays). Gamma(chi) was deduced ...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1987-10-01 00:00:00
abstract::The relative biological effectiveness was determined using sex-linked recessive lethals induced in Drosophila spermatozoa as the biological effect. The sex-linked recessive lethal test, a measure of mutations induced in germ cells and transmitted through successive generations, yields a linear dose-response curve in t...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1989-03-01 00:00:00
abstract::To accurately quantify the number of single-strand breaks (SSBs) induced in plasmid DNA molecules after irradiation, a new type of assay methodology has been explored. The new method is based on the TUNEL (terminal deoxynucleotide transferase dUTP nick end-labeling) assay that was adopted for use under ELISA (enzyme-l...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR1684.1
更新日期:2009-11-01 00:00:00
abstract::Human gliomas are among the most aggressive tumors, and they respond poorly to treatment. The efficacy of surgical, radiation and chemotherapy treatment of these tumors is limited by the development of resistance. Interventions aimed at altering the response of these tumors to radiation or chemotherapy treatments are ...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/0033-7587(2007)168[183:HGUCTW]2.0.CO;2
更新日期:2007-08-01 00:00:00
abstract::Deep underground laboratories (DULs) were originally created to host particle, astroparticle or nuclear physics experiments requiring a low-background environment with vastly reduced levels of cosmic-ray particle interference. More recently, the range of science projects requiring an underground experiment site has gr...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR15083.1
更新日期:2018-09-01 00:00:00
abstract::Female rhesus monkeys received whole-body doses of ionizing radiation in the form of single-energy protons, mixed-energy protons, X rays, and electrons. Endometriosis developed in 53% of the monkeys during a 17-year period after exposure. Incidence rates for endometriosis related to radiation type were: single-energy ...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1991-05-01 00:00:00
abstract::To evaluate whether DNA alterations in mature spermatozoa could stem from DNA damage induced in immature germ cells, testis cells and spermatozoa were analyzed by the comet assay and by the sperm chromatin structure assay 14, 45 and 100 days after in vivo X irradiation of the testes. These times were selected, accordi...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr3053
更新日期:2003-10-01 00:00:00
abstract::There is an ongoing and significant need for radiation countermeasures to reduce morbidities and mortalities associated with exposure of the heart and lungs from a radiological or nuclear incidents. Radiation-induced late effects occur months to years after exposure, stemming from significant tissue damage and remodel...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR14403.2
更新日期:2016-11-01 00:00:00
abstract::Hyperthermic sensitivities of Escherichia coli B/r and Bs-1 were determined for lag-, midlog-, and stationary-phase cells at 47, 48, and 49 degrees C. In both strains midlog-phase cells were strikingly more heat sensitive (100-fold greater killing after 4 h at 48 degrees C) than stationary-phase cells, with intermedia...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1986-04-01 00:00:00
abstract::There is strong evidence that biological response to ionizing radiation has a contribution from unirradiated "bystander" cells that respond to signals emitted by irradiated cells. We discuss here an approach incorporating a radiobiological bystander response, superimposed on a direct response due to direct energy depo...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/0033-7587(2001)155[0402:tbeiro]2.0.co;2
更新日期:2001-03-01 00:00:00
abstract::The distribution and kinetics of proximal tubular cells with abnormally large nuclei, which were observed in irradiated mouse kidneys before any other obvious histological effects, were investigated. Six months after the administration of 13 or 15 Gy, little histopathological change was noted, in the kidneys of C3H mi...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1988-07-01 00:00:00
abstract::A spherical graphite calorimeter was used to determine the ratio of kerma to influence (kerma factor) for neutrons whose mean energy was approximately 14.6 MeV. The calorimeter was used to measure carbon kerma, while activation foils of Al and Au were used to determine the neutron fluence. The calorimeter was construc...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1987-01-01 00:00:00
abstract::New Zealand rabbits, fasted for 12 hours, were subjected to 500 rads of whole-body irradiation. K+-palmitate-1-14C oxidation was assayed with the 600 X g supernatant of thymus and liver homogenates, in the presence of ATP, at various time intervals from irradiation. For a period of 24 hours following irradiation, oxid...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1968-11-01 00:00:00
abstract::The purpose of this study was to determine the antimutagenicity of WR-1065 added after irradiation of cells of cell lines differing in their ability to rejoin radiation-induced DNA double-strand breaks (DSBs). The postirradiation antimutagenicity of WR-1065 at the thymidine kinase locus was demonstrated for L5178Y (LY...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1999-04-01 00:00:00
abstract::We have studied the effect on sister chromatid exchange (SCE) induction in 9L rat brain tumor cells caused by combination treatment with BCNU and X rays. Over the dose and concentration ranges used in these experiments, BCNU induced relatively large numbers of SCEs, while X rays induced few SCEs. When cells were X irr...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1984-01-01 00:00:00
abstract::In this study, we investigated the effect of (131)I gelatin microspheres ((131)I-GMSs) on human hepatocellular carcinoma cells (HepG2) in nude mice (Balb/c) and the biodistribution of (131)I-GMSs after intratumoral injection. The treatment group and control group animals received intratumoral injections of 1 mCi (131)...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR13539.1
更新日期:2014-04-01 00:00:00
abstract::The effect of acute exposure to ultrawideband (UWB) electromagnetic radiation on the Primate Equilibrium Platform (PEP) task, where the monkey's task is to manipulate a joystick control to compensate for the random perturbations in the pitch plane that are generated by a computer at unpredictable intervals, was examin...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1995-07-01 00:00:00
abstract::We have assessed the effects of two radiomodifying conditions, glutathione (GSH) depletion and hypoxia, on the formation and repair of radiation-induced chromatin damage, specifically DNA-protein cross-links (DPC). As measured by a nitrocellulose filter-binding assay, untreated V79 cells contain a low level of DPC (1-...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1988-10-01 00:00:00
abstract::This is the 14th report in a series of periodic general reports on mortality in the Life Span Study (LSS) cohort of atomic bomb survivors followed by the Radiation Effects Research Foundation to investigate the late health effects of the radiation from the atomic bombs. During the period 1950-2003, 58% of the 86,611 L...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr2629.1
更新日期:2012-03-01 00:00:00