Linked Life Data

3665224

Source:http://linkedlifedata.com/resource/pubmed/id/3665224

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1987-12-3
pubmed:abstractText
Theophylline-treated cells of the human melanoma line showed an increase in NK-sensitivity in vitro and a concomitant decrease in tumorigenicity and spontaneous metastasis in Balb/c nude mice. The MeWo cells were heterogeneous and contained related subpopulations which were cloned to produce two cell lines, one hypodiploid (Cd-16) and one hypotetraploid (Ct-1). Prolonged (3 months) or short-term (4 days) treatment of these cell lines with 1 mM theophylline markedly reduced the incidence and size of tumors in Balb/c nude mice early after s.c. injection and their ability to metastasize spontaneously to the lung was also reduced. The effect was much more pronounced with Cd-16 cells, which contain amplified DNA compared to Ct-1 cells which lack DNA amplification. Part of the tumor inhibition caused by theophylline was due to natural killer (NK) cells. Thus, in vivo treatment of nude mice with anti-asialo GM1, a procedure known to remove NK cells, partially reversed the inhibitory effects of theophylline on tumor formation and generation of metastasis by Cd-16 cells. Consistent with this observation theophylline treatment enhanced the in vitro NK sensitivity of Cd-16 cells four-fold whereas Ct-1 was enhanced only slightly. The data suggest that theophylline can act preferentially on certain tumor cell subpopulations to enhance their NK-sensitive phenotype and thereby inhibit their capacity to form tumors and to metastasize in nude mice.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0262-0898
pubmed:author
pubmed:issnType
Print
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
329-39
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:articleTitle
NK-mediated reduction of malignancy in human melanoma cells treated with theophylline.
pubmed:affiliation
Department of Immunology, University of Toronto, Canada.
pubmed:publicationType
Journal Article