β-adrenergic modulation of IL-6/gp130 and SOCS-1 in multiple myeloma: therapeutic strategy for stress induced-inflammatory response

Summary Purpose Multiple Myeloma (MM) is considered an incurable, biologically heterogeneous disease of the plasma cells. The clinical data on the association between stress and the molecular mechanism of stress hormone receptor expression and its relationship with IL‑6 signaling pathway have not yet proposed a clear answer in MM. This study aims to explore the effect of isoproterenol and propranolol, which are beta-adrenergic agonists and antagonists, respectively on suppressor of cytokine signaling (SOCS) and IL-6/gp130 signaling in MM cell lines. Material and methods Four different MM cell lines (KMM‑1, RPMI 8226, LP‑1, and L363) were treated with isoproterenol and propranolol. Optimal dosages of isoproterenol and propranolol were determined, and the mRNA expression levels of IL‑6, gp130 , and SOCS‑1 were examined using qRT-PCR. Results The analysis of our results indicated that propranolol, as a β-adrenoreceptor antagonist, could increase MM cell death and ameliorate IL‑6 and its receptor gp130 in addition to up-regulate SOCS‑1 gene expression. On the other hand, isoproterenol, as a β-adrenoreceptor agonist, could provoke MM cell viability and IL‑6 expression. Conclusions β‑adrenergic signaling seems to affect cell viability through targeting IL-6/gp130 and SOCS‑1 signaling in MM, underscoring the importance of further studies on stress hormones and IL‑6 suppressors as potent candidates for MM therapy.