Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1993-6-9
pubmed:abstractText
In an established colon differentiation model, introduction of a c-H-ras-1 oncogene into a poorly differentiated human colon carcinoma cell line (Clone A) results in changes associated with the acquisition of a more differentiated phenotype. Down-regulation of mdr-1 mRNA was shown to accompany ras-related differentiation events resulting in decreased Pgp synthesis and a significant reduction in membrane Pgp as detected by immunoprecipitation, Western-blot and FACS analysis. Consistent with these observations was a reduction in Pgp-mediated drug resistance associated with Clone-A ras transfectants, with no alteration in drug sensitivity being observed with non-MDR drugs in these cells. An alternative differentiation model involves exposure of Clone-A cells to sodium butyrate. Under these conditions, differentiation-related changes resulted in up-regulation of mdr-1 mRNA and Pgp synthesis, although no alteration in drug sensitivity was recorded. In agreement with this observation, the levels of membrane-associated Pgp remained unchanged throughout the period of exposure to sodium butyrate. This study shows that modulation of Pgp expression in colon differentiation is dependent upon the differentiation induction agent used.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0020-7136
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
54
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
275-81
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:8098015-Antigens, Surface, pubmed-meshheading:8098015-Butyrates, pubmed-meshheading:8098015-Carcinoma, pubmed-meshheading:8098015-Cell Differentiation, pubmed-meshheading:8098015-Cell Membrane, pubmed-meshheading:8098015-Clone Cells, pubmed-meshheading:8098015-Colonic Neoplasms, pubmed-meshheading:8098015-Drug Resistance, pubmed-meshheading:8098015-Flow Cytometry, pubmed-meshheading:8098015-Gene Expression, pubmed-meshheading:8098015-Genes, ras, pubmed-meshheading:8098015-Humans, pubmed-meshheading:8098015-Membrane Glycoproteins, pubmed-meshheading:8098015-P-Glycoprotein, pubmed-meshheading:8098015-Precipitin Tests, pubmed-meshheading:8098015-Proto-Oncogene Proteins p21(ras), pubmed-meshheading:8098015-RNA, Messenger, pubmed-meshheading:8098015-RNA, Neoplasm, pubmed-meshheading:8098015-Transfection, pubmed-meshheading:8098015-Tumor Cells, Cultured
pubmed:year
1993
pubmed:articleTitle
Modulation of mdr-1 expression by a H-ras oncogene in a human colon carcinoma cell line.
pubmed:affiliation
Lederle Laboratories, Pearl River, NY 10965.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.