Linked Life Data

11175665

Source:http://linkedlifedata.com/resource/pubmed/id/11175665

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2001-2-22
pubmed:abstractText
The cell cycle effects, alteration in radiation response, and inherent cytotoxicity of the metal chelators mimosine, desferrioxamine (DFO), N,N'-bis(o-hydroxybenzyl)-ethylenediamine-N,N'-diacetic acid (HBED), and deferiprone (L1) were studied in exponentially growing Chinese hamster V79 cells. Incubation of cells with 200-1000 microM mimosine for 12 h reduced clonogenic survival to 50-60%, while incubation for 24 h reduced survival further to 0.5%. Mimosine treatment resulted in cell cycle blocks at the G(1)/S-phase border and in S phase. Pulse labeling with 5-bromodeoxyuridine indicated that the S-phase cells ceased to actively replicate DNA after only 2 h of mimosine treatment and were unable to replicate DNA for extended periods. Treatment of V79 cells with 600 microM mimosine for 12 h resulted in radiosensitization, yielding a sensitizer enhancement ratio (SER) of 2.7 +/- 0.3 at the 10% survival level. To study the kinetics of the sensitization, V79 cells were incubated with mimosine for various times up to 12 h and irradiated with a single 10-Gy dose of X rays. It was found that the radiosensitization increased continually up to 8 h (from a 3- to a 100-fold difference in survival) and then reached a plateau after 8 h. Mimosine also equally radiosensitized human lung cancer cells having either a normal or mutated TP53 gene, suggesting a TP53-independent mechanism. To test whether iron binding by mimosine was responsible for the observed radiosensitization, additional experiments were performed using the iron chelators DFO, HBED and L1. V79 cells treated with 500 microM of these agents for 8 h followed by various doses of X rays gave SERs similar to that for mimosine (2.0-2.7). These studies indicate that metal chelators are potent radiosensitizers in V79 and human cells. Importantly, when the DFO was preloaded together with Fe(3+) [Fe(III)-DFO], the radiosensitizing effect was lost. These preliminary findings warrant further studies for the possible application of metal chelators as radiation sensitizers in radiation oncology.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0033-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
155
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
304-10
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:11175665-Animals, pubmed-meshheading:11175665-Cell Cycle, pubmed-meshheading:11175665-Chelating Agents, pubmed-meshheading:11175665-Colony-Forming Units Assay, pubmed-meshheading:11175665-Cricetinae, pubmed-meshheading:11175665-Cricetulus, pubmed-meshheading:11175665-DNA Replication, pubmed-meshheading:11175665-Deferoxamine, pubmed-meshheading:11175665-Edetic Acid, pubmed-meshheading:11175665-Fibroblasts, pubmed-meshheading:11175665-Genes, p53, pubmed-meshheading:11175665-Humans, pubmed-meshheading:11175665-Iron Chelating Agents, pubmed-meshheading:11175665-Lung, pubmed-meshheading:11175665-Lung Neoplasms, pubmed-meshheading:11175665-Mimosine, pubmed-meshheading:11175665-Pyridones, pubmed-meshheading:11175665-Radiation-Sensitizing Agents, pubmed-meshheading:11175665-S Phase, pubmed-meshheading:11175665-Tumor Cells, Cultured
pubmed:year
2001
pubmed:articleTitle
Radiation sensitization of mammalian cells by metal chelators.
pubmed:affiliation
Cellular Biochemistry and Human Genetics, Schools of Medicine and Dentistry, Hebrew University, Jerusalem 91120, Israel.
pubmed:publicationType
Journal Article, Comparative Study