Linked Life Data

12745022

Source:http://linkedlifedata.com/resource/pubmed/id/12745022

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2003-5-14
pubmed:abstractText
Targeting of tumor cells with radiolabeled biomolecules is a possible approach to inactivate disseminated tumor cells. However, rapid degradation of the biomolecules after cellular internalization and subsequent excretion of the radioactivity is a problem. We studied the possibility of using dextran as a carrier of radionuclides to improve the intracellular retention. An EGF-dextran conjugate, aimed for targeting of tumor cells overexpressing the EGF-receptor, was used as model. Retention tests were performed with (125)I on different parts: [(125)I]-EGF-dextran-[(125)I], [(125)I]-EGF-dextran and EGF-dextran-[(125)I]. Comparisons were made with [(125)I]-EGF. The radiolabeled compounds were incubated with cultured glioma cells for different times. The cellular retention of radioactivity was then measured for up to 24 h. Expected radiation doses at the cellular level were calculated assuming that (131)I, instead of (125)I, was coupled to EGF and EGF-dextran. The results indicated that the EGF-part of the conjugate was degraded and the EGF-attached radioactivity was rapidly excreted, whereas radioactivity on dextran was retained intracellularly to a high degree, i.e. 70-80% of the radioactivity bound to dextran was still cell-associated after 24 h. The retention after 24 h was significantly higher (p < 0.001) when the radioactivity was on the dextran instead of the EGF-part. The radiolabeled EGF-dextran had a notably high specific radioactivity; up to 11 MBq/microg. There was potential for at least hundred times increased radiation dose per receptor interaction when the radioactivity was on the dextran part. The advantage with radioactivity on the dextran part was the high cellular retention and the high specific radioactivity (higher than previously reported for other residualizing labels) without severe loss of receptor specific binding. Thus, dextran seems suitable as a carrier of radionuclides aimed for therapy and gives potential for a highly increased radiation dose.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0969-8051
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
303-15
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Cellular retention of radioactivity and increased radiation dose. Model experiments with EGF-dextran.
pubmed:affiliation
Division of Biomedical Radiation Sciences, Rudbeck Laboratory, Uppsala University, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't