Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-2-22
pubmed:abstractText
Reactive oxygen species (ROS) have been found to trigger apoptosis in tumor cells. At the same time, telomerase is found to be associated with malignancy and reduced apoptosis. However little is known about the linkage between ROS such as *OH and telomerase/telomere. To address the interrelations between *OH and telomerase/telomere in tumor cell killing, HeLa, 293 and MW451 cells were induced to undergo apoptosis with *OH radicals generated via Fe(2+)-mediated Fenton reactions (0.1 mM FeSO(4) plus 0.3-0.9 mM H2O2) and telomerase activity, telomere length were measured during apoptosis. We found that during *OH-induced apoptosis, telomere shortening took place while no changes in telomerase activity were observed. Our results suggest that *OH-induced telomere shortening is not through telomerase inhibition but possibly a direct effect of *OH on telomeres themselves indicating that telomere shortening but not telomerase inhibition is the primary event during *OH-induced apoptosis. Strikingly, we also found that *OH-induced apoptosis in HeLa cells is caspase-3-independent but is associated with reduction of mitochondrial transmembrane potential. Our results indicate that *OH triggers apoptotic tumor cell death through a telomere-related, caspase-independent pathway.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0014-5793
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
488
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
123-32
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:11163758-Apoptosis, pubmed-meshheading:11163758-Caspase 3, pubmed-meshheading:11163758-Caspases, pubmed-meshheading:11163758-Cell Line, pubmed-meshheading:11163758-DNA Fragmentation, pubmed-meshheading:11163758-Enzyme Activation, pubmed-meshheading:11163758-Flow Cytometry, pubmed-meshheading:11163758-Glutathione, pubmed-meshheading:11163758-HeLa Cells, pubmed-meshheading:11163758-Humans, pubmed-meshheading:11163758-Hydrogen Peroxide, pubmed-meshheading:11163758-Hydroxyl Radical, pubmed-meshheading:11163758-In Situ Nick-End Labeling, pubmed-meshheading:11163758-Membrane Potentials, pubmed-meshheading:11163758-Microscopy, Electron, pubmed-meshheading:11163758-Mitochondria, pubmed-meshheading:11163758-Reactive Oxygen Species, pubmed-meshheading:11163758-Telomerase, pubmed-meshheading:11163758-Telomere
pubmed:year
2001
pubmed:articleTitle
Hydroxyl radical-induced apoptosis in human tumor cells is associated with telomere shortening but not telomerase inhibition and caspase activation.
pubmed:affiliation
Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing, PR China.
pubmed:publicationType
Journal Article