Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
34
pubmed:dateCreated
1994-9-22
pubmed:abstractText
Retinoids mediate their actions via RARs (retinoic acid receptors) and RXRs (retinoid X receptors). Each class of these nuclear retinoid receptors is further subdivided into three species, namely alpha, beta, and gamma. Recent studies demonstrate that estrogen receptor (ER)-positive human breast carcinoma (HBC) cell lines and tumor samples exhibit significantly higher levels of RAR alpha than their ER-negative counterparts. ER-positive HBC cell lines are sensitive to, and ER-negative cell lines are resistant to, growth inhibitory effects of retinoic acid (RA). We previously demonstrated that the expression of functional ERs in an established ER-negative cell line resulted in higher levels of RAR alpha and sensitivity to growth inhibition by RA. To further investigate the major role of RAR alpha in retinoid-mediated inhibition of growth, we transfected RAR alpha cDNA in two RA-resistant ER-negative HBC cell lines. Analyses of different clonal populations of RAR alpha transfectants from each cell line revealed growth inhibition by retinoids. Utilizing RAR- and RXR-class selective retinoids, we further demonstrated that only the RAR alpha-selective retinoids mediated the growth inhibition in these cells, while the RXR-selective retinoids were biologically inert. We thus provide evidence that the molecular mechanisms of retinoid inhibition of HBC proliferation predominantly involve RAR alpha.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
269
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
21440-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Retinoid-resistant estrogen receptor-negative human breast carcinoma cells transfected with retinoic acid receptor-alpha acquire sensitivity to growth inhibition by retinoids.
pubmed:affiliation
Department of Medicine, University of Maryland School of Medicine, Baltimore.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.