Identification of glucocorticoid receptor (GR) binding sites in multiple myeloma. Homo sapiens

Purpose: The glucocorticoid receptor is widely expressed across mutliple tissues, and yet has very tissue specfic actions. This is most likely due to the tissue specific chormatin landscape which dictates GR binding. It identify GR tragets in myeloma as potential therapeutic targets, we have used ChIP-seq to identify myeloma specific GR binding sites. Methods: DNA-chromatin complexes were isolated from MM.1S (GR positive) or MM.1RL (GR negative) cells following a 2 hour treatment with either 1 micromolar dexamethasone or vehicle control. Complexes were immunoprecipitated with either a GR specific antibody or an IgG control and the DNA isolated for next generation sequencing. Results: We identified 8689 high confidence GR binding sites and further correlated those sites to specific genes which are regulated by glucocorticoids through integration with gene expression array data from our lab (submitted to GEO speparately). Conclusions: Overall, our results indentified nearly 400 genes under the direct transcriptional control of glucocorticoids in myeloma cells. Overall design: ChIP seq analysis of GR binding in 2 myeloma cell lines after 2 hour treatment with glucocorticoids or vehicle control.