Linked Life Data

1824825

Source:http://linkedlifedata.com/resource/pubmed/id/1824825

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1991-2-28
pubmed:abstractText
To investigate the possibility that anticancer drugs combined with cytokines may show increased activity, human tumor cells were treated with combinations of human recombinant interleukin 1 alpha (rIL-1 alpha) and etoposide (VP-16). The cytotoxicity of these combinations was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay using rIL-1 alpha-sensitive A375-C6 melanoma cells and A375-C5 cells, a clonal variant line that is resistant to IL-1 alpha. Data were analyzed for synergism by the median effect principle of T-C. Chou and P. Talalay (J. Biol. Chem., 252: 6438-6442, 1977). At a dose ratio of VP-16 to rIL-1 alpha of 12 nM:1 unit/ml in either simultaneous or sequential exposure (VP-16 first), the calculated combination index values indicated synergistic cytotoxicity toward both A375-C6 cells and A375-C5 cells. IL-1 alpha treatment 24 h prior to VP-16 exposure had no advantage over simultaneous treatment. Surface IL-1 alpha receptors on both A375-C6 and A375-C5 cells were measured using 125I-radiolabeled rIL-1 alpha binding; A375-C6 cells had 701 +/- 128 (SD) receptor molecules/cell and A375-C5 cells only had 58 +/- 33 receptor molecules/cell. The dissociation constants for IL-1 alpha were similar in both cell types (19 +/- 6 pM for A375-C6 and 17 +/- 2 pM for A375-C5). The specific binding of rIL-1 alpha to the surface IL-1 alpha receptors of both sensitive and resistant cells was significantly increased in a dose-dependent fashion by the prior treatment with VP-16 (1.75-fold on A375-C6 cells and 3.5-fold on A375-C5 cells). VP-16 also enhanced the internalization of receptor-bound rIL-1 alpha, suggesting that a possible mechanism of the synergistic cytotoxicity of rIL-1 alpha and VP-16 might be related to the modulation of rIL-1 alpha receptors by VP-16, resulting in increased internalization of rIL-1 alpha.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
51
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
769-74
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
A role for the interleukin 1 receptor in the synergistic antitumor effects of human interleukin 1 alpha and etoposide against human melanoma cells.
pubmed:affiliation
Clinical Pharmacology Branch, National Cancer Institute, NIH, Bethesda, Maryland 20892.
pubmed:publicationType
Journal Article