Receptor density dictates the behavior of a subset of steroid ligands in glucocorticoid receptor-mediated transrepression

Dehydroepiandrosterone and its 7-hydroxylated metabolites do not interfere with the transactivation and cellular trafficking of the glucocorticoid receptor

“…We selected COS-7 cells for transfection assays because of the hGR cDNA availability and the possibility of transfectable contructs. The decision to use COS-7 cells was influenced by several studies reporting them to be good models for transfections [18,24,25] and not expressing any functional GR [24,26]. Yet other works that had examined the GC metabolism in COS-7 cells yielded contradictory results.…”

A Conserved Protein Motif Is Required for Full Modulatory Activity of Negative Elongation Factor Subunits NELF-A and NELF-B in Modifying Glucocorticoid Receptor-regulated Gene Induction Properties

“…Interestingly, the EC 50 is not determined by the steroid binding affinity for receptor and can be highly variable even for the same gene under various settings (1)(2)(3). The partial agonist activity (PAA) 5 of an antisteroid is the reduced activity that most antisteroids display under assorted conditions. The original thought that antisteroids, or antagonists, have no intrinsic activity and block all activity of agonists has given way to the realization that an "antagonist" can display a partial amount of full agonist activity.…”

“…: 301-496-6796; Fax: 301-402-3572; E-mail: stoneys@helix.nih.gov. 5 The abbreviations used are: PAA, partial agonist activity; GR, glucocorticoid receptor; GRE, glucocorticoid response elements; NELF, negative elongation factor; ER, estrogen receptor; GILZ, glucocorticoid-induced leucine zipper; Dex, dexamethasone; Dex-Mes, Dex-21-mesylate; qRT-PCR, quantitative real-time PCR; PIC, protease inhibitor cocktail; LBD, ligand-binding domain; DBD, DNA-binding domain; KD, knockdown; CLS, concentrationlimiting step; TSS, transcription start site; sh, short helical; EGFP, enhanced green fluorescent protein.…”

The Contraceptive Depot Medroxyprogesterone Acetate Impairs Mycobacterial Control and Inhibits Cytokine Secretion in Mice Infected with Mycobacterium tuberculosis

“…DMPA has been shown by many, including us, to have partial GR agonist activity and has been shown to alter the expression of glucocorticoid receptorregulated genes (12). However, DMPA is probably better referred to as a selective GR modulator, as it can act as an agonist as well as an antagonist depending on the cellular milieu (13).…”