Growth hormone inhibits the interleukin-6 induced junB protooncogene and fibrinogen expression in HepG2 human hepatoma cells

Growth hormone (GH) and interleukin-6 (IL-6) play important regulatory role s in multiple endocrinological and immunological functions. In this study w e examined whether GH can modulate the actions of IL-6. In HepG2 human hepa toma cells we studied the effects of different GH concentrations on the exp ression of the junB mRNA as an early and on the biosynthesis of fibrinogen protein as a late model of IL-6-related hepatic response. Both GH and IL-6 alone induced the expression of junB and fibrinogen but GH significantly in hibited the actions of higher (10 and 20 ng/ml) IL-6 concentrations in a do se dependent manner. These findings further underline the importance of int erplay between the effectiveness of IL-6 and GH in various physiological pr ocesses.