Glucocorticoid (GC) hormones are used in the treatment of hematopoietic malignancies. When the GC binds to the glucocorticoid receptor (GR) protein, c-Myb and GR are recruited at the Glucocorticoid Response Unit in the DNA. Here we demonstrate that c-Myb interacts with the GR and that decreasing c-Myb amounts reduces the levels of GR transcripts and protein in 697 pre-B-acute lymphoblastic leukemia (ALL) cells. Furthermore, the auto-upregulation of GR promoter 1C and promoter 1D is blunted at reduced c-Myb levels. Taken together, these data show that c-Myb is a direct, key regulator of the GR. Unexpectedly, the reduction in c-Myb levels increased the sensitivity of the cells to steroid-mediated apoptosis. This was because the reduction in c-Myb itself decreases cell viability, and the residual GR remained above the threshold needed to trigger apoptosis. These studies show the mutual importance of c-Myb and the GR in controlling survival of pre-B ALL cells. © 2012 Elsevier Ireland Ltd.
Sarvaiya, P. J., Schwartz, J. R., Geng, C. dong, & Vedeckis, W. V. (2012). C-Myb interacts with the glucocorticoid receptor and regulates its level in pre-B-acute lymphoblastic leukemia cells. Molecular and Cellular Endocrinology, 361(1–2), 124–132. https://doi.org/10.1016/j.mce.2012.03.024