The regulation of p21^Waf1/Cip1, p27^Kip1 and p57 ^Kip2 gene expression in response to hydrocortisone, progesterone and ß-estradiol in HL-60 myeloid leukemia cells

Steroid agents have crucial regulatory effects on cell differentiation and proliferation of different cell types. In this study, the influence of progesterone, ß-estradiol and hydrocortisone on the expression of cyclin dependent kinase inhibitor (CDKI) genes, p21Waf1/Cip1, p27Kip1 and p57Kip2 was assessed in HL-60 myeloid leukemia cells. Although treatment with these steroid agents did not significantly change the morphology of HL-60 cells, expression levels of p21 and p27 genes were modulated. p57 gene was not expressed in HL-60 cells. The overall data implied that G1/S transition in myeloid leukemia cells may be primarily regulated through p21Waf1/Cip1 and with a lesser extent through p27Kip1 expression upon incubation with steroids.