Trichostatin A, sodium butyrate, and 5-aza-2′-deoxycytidine alter the expression of glucocorticoid receptor α and β isoforms in Hut-78 T- and Raji B-lymphoma cell lines

The glucocorticoid receptor (GR) is mainly expressed as nine-exon alternatively spliced variants, encoding functional GRU and nonfunctional GRP. Overexpression of GRP splice variant was found in glucocorticoid-resistant patients with some autoimmune diseases and hernatological malignancies. Employing reverse transcription, real-time quantitative PCR, and western blot analysis, we determined an effect of trichostatin A (T SA), sodium butyrate (NaBu) and 5-aza- 2'-deoxycytidine (5-dAzaC) on GR alpha and GR beta expression in Hut-78 T- and kaji B-lymphoma cell lines. We found that TSA, NaBu, and 5-dAzaC significantly increase the expression of GR alpha transcript and protein, whereas GRP transcript and protein expression was profoundly decreased in Hut-78 T- and Raji B- lymphoma cell lines. Our observation suggests that changes of epigenetic milieu inside cells may alter the expression of GRa and GRP isoforms. (c) 2007 Elsevier Masson SAS. All rights'reserved.