Linked Life Data

7690896

Source:http://linkedlifedata.com/resource/pubmed/id/7690896

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1993-10-15
pubmed:abstractText
Okadaic acid (OA), a potent tumor promoter and an inhibitor of protein phosphatase 1 and 2A, induced sister-chromatid exchanges (SCEs) in human lymphoblastoid cells and Chinese hamster ovary cells at low concentrations of 2-10 nM, when the cells were grown for two cell cycles in the presence of OA and bromodeoxyuridine (BrdUrd). Prolonged treatment with OA prior to addition of BrdUrd did not induce SCEs, indicating an essential role of BrdUrd. A similar important role of BrdUrd in SCE induction has been reported in the cases of benzamide (BA) (Natarajan et al., 1981) and camptothecin (CPT) (Zhao et al., 1992), which are inhibitors of poly(ADP-ribose)polymerase and DNA topoisomerase I (topo I), respectively. Unlike many DNA-damaging agents, they are required to be present during S phase along with BrdUrd in the medium and/or in the parental DNA as BrdUMP. Thus OA, like BA and CPT, is a new type of SCE inducer. Exposing cells to a combined treatment with OA, BA and CPT, a significantly higher level of SCEs was induced than that expected if the numbers of SCE caused by these three inhibitors were additive, while no such synergistic increase was seen in every combination of two agents. Since both phosphorylation and poly(ADP-ribosyl)ation have been known to modify topo I activity, the results suggest a common involvement of topo I for SCE formation by OA, BA and CPT. In addition to SCE induction, OA resulted in an increase of mitotic cells which were characterized by a marked chromosome condensation. OA also induced chromosome fragmentation/pulverization in human lymphoblastoid cells and fragmented nuclei in Chinese hamster cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0027-5107
pubmed:author
pubmed:issnType
Print
pubmed:volume
289
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
275-80
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:7690896-Animals, pubmed-meshheading:7690896-Benzamides, pubmed-meshheading:7690896-Bromodeoxyuridine, pubmed-meshheading:7690896-CHO Cells, pubmed-meshheading:7690896-Camptothecin, pubmed-meshheading:7690896-Cell Line, pubmed-meshheading:7690896-Cricetinae, pubmed-meshheading:7690896-Cricetulus, pubmed-meshheading:7690896-DNA Replication, pubmed-meshheading:7690896-DNA Topoisomerases, Type I, pubmed-meshheading:7690896-Drug Synergism, pubmed-meshheading:7690896-Enzyme Activation, pubmed-meshheading:7690896-Ethers, Cyclic, pubmed-meshheading:7690896-Humans, pubmed-meshheading:7690896-Lymphocytes, pubmed-meshheading:7690896-Okadaic Acid, pubmed-meshheading:7690896-Phosphoprotein Phosphatases, pubmed-meshheading:7690896-Phosphorylation, pubmed-meshheading:7690896-Poly(ADP-ribose) Polymerases, pubmed-meshheading:7690896-Protein Phosphatase 1, pubmed-meshheading:7690896-Sister Chromatid Exchange
pubmed:year
1993
pubmed:articleTitle
Okadaic acid, a protein phosphatase inhibitor, induces sister-chromatid exchanges depending on the presence of bromodeoxyuridine.
pubmed:affiliation
Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.
pubmed:publicationType
Journal Article