Abstract：
:These studies were carried out to examine the capacity of alpha-difluoromethylornithine (DFMO) to modulate cell proliferation and apoptosis in cells of squamous cell carcinomas (SCCs) of the head and neck. Exposure of cells to DFMO (5 mM for 48 h) depleted intracellular putrescine and spermidine levels (greater than 5-fold) and inhibited proliferation of the cells without manifestation of cytotoxicity as measured by a clonogenic assay. Exposure of the cells to DFMO did not influence the survival response after exposure to single-dose radiation between 0 and 10 Gy. Treatment of polyamine-depleted cells with 200 nM staurosporine amplified apoptosis 65% (1.65-fold) over that in controls, as determined by flow cytometry. The increased apoptosis after DFMO treatment was effectively inhibited by the addition of 1 mM putrescine or spermidine. Cleavage of poly(ADP-ribose) polymerase (PARP) illustrated that the staurosporine treatment induced apoptosis in the cells within 6 h. Analysis of PARP cleavage indicated that treatment with DFMO accelerated the kinetics of progression of apoptosis but did not influence the sensitivity of cells to 10 nM-1 microM staurosporine. These data suggest an involvement of endogenous polyamines in modulation of proliferation kinetics and apoptosis in human SCCs and suggest opportunities to explore new therapeutic strategies in head and neck cancer patients to be treated with radiation therapy.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Bock JM,Pickart MA,Pink JJ,Harari PMsubject
Has Abstractpub_date
1999-12-01 00:00:00pages
604-10issue
6eissn
0033-7587issn
1938-5404journal_volume
152pub_type
杂志文章abstract：:The effects of ionizing radiation, with or without the anti-angiogenic agent anginex (Ax), on multiple myeloma growth were tested in a SCID-rab mouse model. Mice carrying human multiple myeloma cell-containing pre-implanted bone grafts were treated weekly with various regimens for 8 weeks. Rapid multiple myeloma growt...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1734.1
更新日期：2010-06-01 00:00:00
abstract：:The susceptibility to inducible SOS repair of 5,6-dihydroxy-dihydrothymine (t') damage in single-stranded phi X174 DNA has been measured. Following exposure to osmium tetroxide, which introduces t' damage in DNA under the conditions used, biological survival of the DNA infected into spheroplasts of Escherichia coli wh...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-03-01 00:00:00
abstract：:Vascular change by the combined treatments of radiation and hyperthermia was studied. The legs of rats were irradiated with 2000 rad of X rays in a single dose and heated at 43.0 degrees C for 1 hr at various times after irradiation, and the blood flow and vascular volume in the skin and muscle were determined with 12...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-05-01 00:00:00
abstract：:A study has been made of methods for rapidly inactivating cells of E. coli at neutral pH to prevent enzymatic, chemical, or physical modification to DNA damaged by irradiation. The radiation was delivered in a fraction of a second using an electron accelerator. Cell inactivation was with ethanol or a solution (CSE) co...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-11-01 00:00:00
abstract：:Radiation-induced cell death is thought to be caused by nuclear DNA damage that cannot be repaired. However, in this study we found that a delayed increase of mitochondrial reactive oxygen species (ROS) is responsible for some of the radiation-induced cell death in normal human fibroblast cells. We have previously rep...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13772.1
更新日期：2015-04-01 00:00:00
abstract：:In previous studies we determined a gene expression signature in baboons for predicting the severity of hematological acute radiation syndrome. We subsequently validated a set of eight of these genes in leukemia patients undergoing total-body irradiation. In the current study, we addressed the effect of intra-individu...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR15013.1
更新日期：2018-09-01 00:00:00
abstract：:The effects of bromodeoxyuridine (BrdUrd) substitution for thymidine on gamma-ray-induced strand breakage were determined in single- and double-stranded oligonucleotides and double-stranded oligonucleotides containing a mismatched bubble region. BrdUrd does not sensitize complementary double-stranded DNA to gamma-ray-...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3267
更新日期：2004-12-01 00:00:00
abstract：:Asynchronously growing V79 cells were assayed for mutation induction following exposure to hyperthermia either immediately before or after being irradiated with 60Co gamma rays. Hyperthermia exposures consisted of either 43.5 degrees C for 30 min or 45 degrees C for 10 min. Each of these heat treatments resulted in a ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1989-08-01 00:00:00
abstract：:The effect of hypoxia on the induction of and recovery from damage by radiation alone and in combination with heat has been investigated using plateau-phase Chinese hamster ovary (CHO) cells. Postirradiation hypoxia reduced the potentially lethal damage recovery (PLDR) in cells irradiated under an euoxic state and com...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-02-01 00:00:00
abstract：:To approach treatment of micrometastases of steroid receptor-rich cancers using estrogen receptor-directed therapy with Auger electrons, multicellular spheroids of the estrogen receptor-rich human breast cancer cell line, MCF-7, were prepared and exposed to a range of concentrations of an Auger electron-emitting estro...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1999-05-01 00:00:00
abstract：:Thymic explant cultures were used to study the radiosensitivity of nonlymphoid thymic components in dogs. Thymic fragments from fetal (50 days gestation), newborn, and juvenile (70 days old) dogs were irradiated in vitro at 0, 0.5, 1, 2, or 4 Gy prior to culture. Colonies were classified as epithelial, spindle, or mix...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-07-01 00:00:00
abstract：:Pentamidine is similar to rhodamine-123 in chemical structure and state of electron charge, and rhodamine-123 was previously shown to be a hyperthermic sensitizer under appropriate cell culture conditions. The present experiments were carried out to determine whether pentamidine would potentiate hyperthermic cell kill...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-11-01 00:00:00
abstract：:An induction-type radiofrequency generator was used to heat thigh implants of the VX2 rabbit carcinoma. The tumor temperature could be easily raised to over 50 degrees C, while the temperature of normal adjacent muscle generally remained at about 43 degrees C. The marked hypovascularity of the tumor, as demonstrated a...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-02-01 00:00:00
abstract：:Evaluation of the probability of biological phenomena per cell by colony formation, requires knowledge not only of the number of cells at risk but also of their microdistribution. In the present study, the influence of cellular multiplicity (number of cells per potential colony-forming unit) on the determination of ra...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-06-01 00:00:00
abstract：:A new model for the survival of bacteria exposed to ionizing radiation is constructed in the framework of a target theory based on microdosimetric concepts, where single- and double-strand breaks of DNA and their repair in vivo can be described consistently in terms of the microdosimetric quantity j (number of effecti...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-04-01 00:00:00
abstract：:Polonium-210 is a naturally occurring radioactive element that decays by emitting an alpha particle. It is in the air we breathe and also a component of tobacco smoke. Polonium-210 is used as an anti-static device in printing presses and gained widespread notoriety in 2006 after the poisoning and subsequent death of a...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13395.1
更新日期：2014-02-01 00:00:00
abstract：:Fractionated whole-brain irradiation (fWBI) is a mainstay of treatment for patients with intracranial neoplasia; however late-delayed radiation-induced normal tissue injury remains a major adverse consequence of treatment, with deleterious effects on quality of life for affected patients. We hypothesize that cerebrova...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14616.1
更新日期：2017-05-01 00:00:00
abstract：:Survival of colony-forming units-spleen (CFU-S) was measured after single doses of photons or heavy charged particles from the BEVALAC. The purposes were to define the radiosensitivity to heavy ions used medically and to evaluate relationships between relative biological effectiveness (RBE) and dose-averaged linear en...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-10-01 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：:We report results for chromosomal aberrations in human peripheral blood lymphocytes after they were exposed to high-energy iron ions with or without shielding at the HIMAC, AGS and NSRL accelerators. Isolated lymphocytes were exposed to iron ions with energies between 200 and 5000 MeV/nucleon in the 0.1-1-Gy dose rang...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3362.1
更新日期：2005-10-01 00:00:00
abstract：:V79 Chinese hamster cells were irradiated in the presence of different amounts of boric acid with thermal neutrons at the Medical Research Reactor at Brookhaven National Laboratory. From the linear dose-survival curves observed, a D0 value of 66 rad for the 10B(n, alpha) 7Li neutron capture reaction was obtained. No d...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-05-01 00:00:00
abstract：:Mice were irradiated with 1 Gy of fission neutrons. At intervals up to 15 days after irradiation undifferentiated spermatogonia were counted in whole mounts of seminiferous tubules in up to eight stages of the epithelial cycle. From Day 6 onward lower numbers of spermatogonia were found in the areas which were in stag...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-03-01 00:00:00
abstract：:Hyperthermia sensitization or tolerance is subject to cellular events that may occur at membrane, nuclear, and cytoplasmic sites. We have studied the effects of elevated temperatures on the oxidative-reductive state of the cell by measuring and altering glutathione (GSH) concentrations. GSH plays a pivotal role in mai...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-09-01 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：:Radon is recognized as a public health concern for indoor exposure. Precise quantification derived from occupational exposure in miners is still needed for estimating the risk and the factors that modify the dependence on cumulated exposure. The present paper reports on relationship between radon exposure and lung can...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR0848.1
更新日期：2008-02-01 00:00:00
abstract：:Dose assessment after radiological disasters is imperative to decrease mortality through rationally directed medical intervention. Our goal was to identify biomarkers capable of qualitative (nonirradiated/irradiated) and/or quantitative (dose) assessment of radiation exposure. Using real-time quantitative PCR, biodosi...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2419.1
更新日期：2011-07-01 00:00:00
abstract：:Irradiation from internally deposited radionuclides induces malignant tumors. Ingested long-lived radionuclides accumulate in specific organs that are irradiated throughout life. To elucidate why the development of malignant tumors requires long-term internal exposure, of the order of decades, despite the fact that ir...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1492.1
更新日期：2009-04-01 00:00:00
abstract：:Fluorescence in situ hybridization procedures were used to examine the influence of chromosome locus on the frequency and type of chromosome aberrations induced by 60Co gamma rays in the human lymphoblastoid cell line TK6. Aberrations involving the X chromosome were compared to those involving the similarly sized auto...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-03-01 00:00:00
abstract：:In this article, we describe recent methodological enhancements and findings from the dose reconstruction component of a study of health risks among U.S. radiologic technologists. An earlier version of the dosimetry published in 2006 used physical and statistical models, literature-reported exposure measurements for t...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13542.1
更新日期：2014-11-01 00:00:00
abstract：:Radiation-induced endothelial cell apoptosis is involved in the development of many radiation injuries, including radiation-induced skin ulcers. The proangiogenic growth factors basic fibroblast growth factor (bFGF, NUDT6) and VEGF enhance endothelial cell survival. In the present study, we used primary cultured human...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3158
更新日期：2004-06-01 00:00:00
