title: Gene expression profile of human lymphoid CEM cells sensitive and resistant to glucocorticoid-evoked apoptosis.
abstract: Three closely related clones of leukemic lymphoid CEM cells were compared for their gene expression responses to the glucocorticoid dexamethasone (Dex). All three contained receptors for Dex, but only two responded by undergoing apoptosis. After a time of exposure to Dex that ended late in the interval preceding onset of apoptosis, gene microarray analyses were carried out. The results indicate that the expression of a limited, distinctive set of genes was altered in the two apoptosis-prone clones, not in the resistant clone. That clone showed altered expression of different sets of genes, suggesting that a molecular switch converted patterns of gene expression between the two phenotypes: apoptosis-prone and apoptosis-resistant. The results are consistent with the hypothesis that altered expression of a distinctive network of genes after glucocorticoid administration ultimately triggers apoptosis of leukemic lymphoid cells. The altered genes identified provide new foci for study of their role in cell death.
authors.affiliation: Department of Biology, California State University, Northridge, CA 91330-8303, USA.
authors.forename: Rheem D
authors.initials: RD
authors.lastname: Medh
authors.forename: M Scott
authors.initials: MS
authors.lastname: Webb
authors.forename: Aaron L
authors.initials: AL
authors.lastname: Miller
authors.forename: Betty H
authors.initials: BH
authors.lastname: Johnson
authors.forename: Yuriy
authors.initials: Y
authors.lastname: Fofanov
authors.forename: Tongbin
authors.initials: T
authors.lastname: Li
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Wood
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Luxon
authors.forename: E Brad
authors.initials: EB
authors.lastname: Thompson
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D045744:Cell Line, Tumor; D002999:Clone Cells / Q000187:drug effects; D016000:Cluster Analysis; D003907:Dexamethasone / Q000494:pharmacology*; D004351:Drug Resistance / Q000235:genetics*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D005938:Glucocorticoids / Q000494:pharmacology; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects / Q000473:pathology*; D011401:Promoter Regions, Genetic; D020218:Response Elements
chemical_list: D005938:Glucocorticoids; D003907:Dexamethasone