Soluble IL-6R in plasma cell dyscrasias

The understanding of the biology of multiple myeloma has advanced significantly in the past few years. The identification of the pivotal role of Interleukin-6 (IL-6), the soluble IL-6 receptor (sIL-6R), and how the ligand receptor complex interacts with the signal transducer gp130 has provided new biological insights into plasma cell disorders. Some studies have suggested that sIL-6R levels may have prognostic significance in MM, however this is not a consistent finding. Here the biology and function of IL-6 and sIL-6R are reviewed and the clinical significance of sIL-6R discussed.