Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1999-2-9
pubmed:abstractText
9-Aminocamptothecin (9-AC) inhibited cell growth and DNA synthesis in HCT 116 human colon cancer cells in a concentration- and time-dependent manner. Interference with nascent DNA chain elongation was monitored using pH step alkaline elution. After a 3-day 9-AC exposure, 38% (10 nM) and 53% (50 nM) of the total [3H]DNA eluted with pH steps 11.3-11.7, compared to 9% in control cells. Effects on nascent DNA integrity were also evaluated by fixed elution with pH 12.1 buffer. After a 3-day exposure to 9-AC, 27% (10 nM) and 82.5% (50 nM) of the total [3H]DNA eluted relative to control. Paired bone marrow samples were then obtained in 10 patients before treatment and between 42 and 72 h of a continuous i. v. infusion of 9-AC (35-74 microgram/m2/h for 72 h). The mononuclear cells were incubated with [3H]dThd for 2 or 4 h, and then analyzed using either pH step or fixed pH alkaline elution, respectively. In seven patients receiving >/=47 microgram/m2/h 9-AC, 4% +/- 1.5% (mean +/- SE) of the total [3H]DNA eluted with pH steps </= 11.7 in the pretreatment samples compared to 13% +/- 3.6% during 9-AC (P = 0. 037). An altered fixed pH elution profile of nascent DNA was noted in two patients treated with 59 and 74 microgram/m2/h 9-AC compared to baseline. DNA synthesis was inhibited by 89% +/- 5% during infusion of >/=59 microgram/m2/h 9-AC (n = 7). Since hematological toxicity is dose limiting on this 9-AC schedule, these cellular pharmacodynamic studies provide evidence of a DNA-directed cytotoxic effect of 9-AC in a sensitive host target tissue.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1078-0432
pubmed:author
pubmed:issnType
Print
pubmed:volume
1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1345-51
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Effects of 9-aminocamptothecin on newly synthesized DNA in patient bone marrow samples.
pubmed:affiliation
National Cancer Institute-Navy Medical Oncology Branch, Clinical Oncology Program, Division of Cancer Treatment, National Cancer Institute, National Naval Medical Center, Bethesda, Maryland 20889-5105, USA.
pubmed:publicationType
Journal Article, Clinical Trial, Clinical Trial, Phase I