The effect of dexamethasone on the clonal proliferation of human acute myelogenous leukemia cells was studied using the two available human acute myelogenous leukemia lines KG-1 and HL-60. The cells were cloned in agar in the presence of colony-stimulating activity with and without dexamethasone. Colony formation by KG-1 cells was inhibited by dexamethasone at a concentration of 10-7 M, and a 50% reduction occurred at 10-5 M dexamethasone. Dexamethasone had no effect on HL-60 colony formation. Direct assessment of dexamethasone binding showed that both KG-1 and HL-60 cells had high-affinity glucocorticoid receptors with a mean 10,300 and 15,600 binding sites/cell with a K(d) of 3.3 X 10-9 M and 4.2 X 10-9 M (r ≥ -0.95), respectively. Binding competition studies confirmed the specificity of these glucocorticoid receptors. No correlation was noted between the number of glucocorticoid receptors and the in vitro inhibition of colony formation. A variety of other steroids was tested and found to have no effect on clonal proliferation of the leukemic cells.
|Original language||English (US)|
|Number of pages||4|
|State||Published - Mar 1 1980|
ASJC Scopus subject areas
- Cancer Research