Potential role of NF-kB and RXR beta like proteins in interferon induced HLA class I and beta globin gene transcription in K562 erythroleukaemia cells

Positive effects of biological response modifiers on cancer cells are usually measured using markers for increased immunogenicity as well as those for increased differentiation of the cells. An increase in levels of HLA class I antigens and the adult (beta) globin molecules are two such markers that may be used to assess the effect of modulators like interferons on the K562 erythroleukaemia cell line. Although interferon mediated up regulation of gene expression is thought to be primarily regulated by binding of proteins to the Interferon responsive cis elements in the promoters of IFN responsive genes, recent evidence has shown the induction of other transcriptional activators in response to IFN treatment. We present evidence for one such instance wherein up regulation of HLA class I and beta globin gene transcription are accompanied by induction of binding activities similar to RXR beta and kB proteins in K562 cells.