Linked Life Data

8914817

Source:http://linkedlifedata.com/resource/pubmed/id/8914817

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-5-5
pubmed:abstractText
A fluorescence image cytometry technique was developed to measure the effects of topotecan, a topoisomerase I inhibitor, on the nuclear expression of topoisomerase II alpha in a series of patients with refractory or relapsed acute myeloid leukemia (AML). We used a commercially available affinity-purified rabbit polyclonal antibody and a fluorescein-conjugated secondary antibody. By using DAPI as a DNA counterstain and dual wavelength excitation, it was possible to measure enzyme expression in the cell nucleus, and to examine its cell cycle phase distribution. In human acute leukemia cell lines, topoisomerase II alpha expression was greatest in late S and G2 phases, but in leukemia patient samples the enzyme expression appeared to be much less cell cycle dependent. There was considerable interpatient variation in the effects of topotecan on topoisomerase II alpha expression in the leukemia patients, with a threefold increase in the median value after 48 h followed by a decline to pretreatment levels after 5 days of treatment with the topoisomerase I inhibitor. Although these findings should be treated with caution because of the small number of cases studied, they support the prediction that topoisomerase I inhibitors might be capable of increasing sensitivity to topoisomerase II active drugs such as anthracyclines and epipodophyllotoxins by upregulating topoisomerase II expression. They also illustrate the potential value of fluorescence image cytometry for making sequential measurements of the effects of drug resistance modulating agents in cancer patients.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0196-4763
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
25
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
205-10
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Effects of topoisomerase I inhibition on the expression of topoisomerase II alpha measured with fluorescence image cytometry.
pubmed:affiliation
Department of Oncologic Pathology, Ontario Cancer Institute/Princess Margaret Hospital, Toronto, Canada.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.