Effects of natural beta-interferon and recombinant alpha-2B-interferon on proliferation, glucocorticoid receptor content, and antigen expression in cultured HL-60 cells

Abstract

In the current study, we investigated the effects of natural beta‐interferon (β‐IFN) and recombinant alpha‐2b‐interferon (α‐IFN) on the growth of the HL‐60 cell line. Cells cultured in a medium that contains various concentrations (from 10 to 1000 IU/ml) of interferons showed a growth inhibition, which reaches the maximum after a 6‐day treatment, at the highest dose used. Furthermore, we studied the effect of both β‐IFN and α‐IFN on the level of glucocorticoid receptors. This was enhanced more than 30% with respect to control in HL‐60 cells exposed for 24 hours to concentrations of β‐IFN that ranged from 100 to 1000 IU/ml. The increase of the receptor amount was seen even if cells were treated for 5 days, and was not accompanied by a modification of antigen expression of HL‐60 cells. α‐IFN did not modify the glucocorticoid receptor level substantially in our experimental conditions. Our data indicate that both β‐IFN and α‐IFN regulate HL‐60 cell proliferation. Additional studies are required to clarify if modifications of the receptor level induced by β‐IFN could be related to the modulation of hormone‐sensitivity in this model.