[Changes in the transcription activity of c-myc genes and heat shock proteins (HSP 70) after incubation of mouse plasmacytoma cells with dexamethasone].

The transcription of genes c-myc and hsp70 following inhibition of plasmacytoma cells proliferation by glucocorticoid hormone dexamethasone has been investigated. The dynamics of [3H] thymidine incorporation into the plasmacytoma cells DNA after incubation with dexamethasone has been studied. It declines after 8-35 h incubation with dexamethasone. The transcriptional activity of c-myc gene decreased after 3-12 h of incubation with hormone and restored to the original level at 24-30 h. The level of transcription of hsp 70 gene decreased after 12-48 h of introduction of hormone. Heat-shock treatment resulted in decrease of c-myc expression and to some increase of the transcription of hsp 70 gene. So, the dynamics of transcriptional activity of the genes c-myc and hsp70 are different and independent.