OBJECTIVETo study the alteration and significance of IL-6, vascular endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF-1) in MM progression and the interaction between the three cytokines.

METHODSBone marrow samples from 28 patients with multiple myeloma (MM) (evolution group and steady group), 10 iron deficiency anemia (as normal control) and 2 monoclonal gammopathy of undetermined significance (MGUS) were studied. Bone marrow stromal cells (BMSCs) were established from the bone marrow MNCs. ELISA was performed to detect the concentration of IL-6, VEGF, IGF-1 in culture supernates.

RESULTS(1) The levels of IL-6 and VEGF secreted by BMSCs were increased in an order from normal control to steady group to evolution group (P < 0.05). However, the concentration of IGF-1 did not increase in MM patients (P > 0.05). (2) The levels of IL-6, VEGF and IGF-1 in the coculture supernates of U266 and BMSCs were increased significantly (P < 0.05), being in an ascending order from normal control to steady group to evolution group (P < 0.05). (3) BMSCs stimulated by exogenous IL-6, VEGF or IGF-1, secreted more VEGF, IGF-1/IL-6, IGF-1/VEGF, IL-6 than unstimulated (P < 0.05). (4) The levels of IL-6, VEGF, IGF-1 secreted by BMSCs from MGUS were similar to that from control group.

CONCLUSIONSIL-6, VEGF, IGF-1 levels associate with evolution of MM; IL-6, VEGF and IGF-1 induce an increase in cytokines secretion of BMSCs.