RESUMO
<p><b>OBJECTIVE</b>To 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.</p><p><b>METHODS</b>Bone 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.</p><p><b>RESULTS</b>(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.</p><p><b>CONCLUSIONS</b>IL-6, VEGF, IGF-1 levels associate with evolution of MM; IL-6, VEGF and IGF-1 induce an increase in cytokines secretion of BMSCs.</p>