The role of Interleukin-17A and Interleukin-17E in multiple myeloma patients.

BACKGROUND: Tumor growth in multiple myeloma (MM) is regulated by the cytokine networks which are produced by myeloma cells and the microenvironment of the bone marrow. Interleukin-17 (IL-17) is implicated in the increased angiogenesis in the bone marrow of MM. Recent studies reported elevated levels of interleukin 17A (IL-17A) in the sera of patients with advanced stages according to Durie-Salmon classification. MATERIAL/METHODS: We compared the concentration of IL-17A and IL-17E in the blood serum of 34 newly diagnosed MM patients with healthy subjects' sera. We also evaluated the concentration of IL-17A and IL-17E in the blood serum of MM patients and the relation to the percentage of plasma cells and other clinical parameters. The concentration of IL-17E and IL-17A of healthy subjects and patients with MM was assessed by enzyme-linked immunosorbent assay (ELISA). RESULTS: Our data confirm that IL-17A and IL-17E serum levels were significantly higher in all MM patients and also in patients with advanced stage compared with healthy subjects. We found the correlation between serum levels of IL-17A in MM patients and percentage of plasma cells. Our results also showed that if serum levels of IL-17E were higher in MM patients, the percentage of plasma cells and beta-2-microglobulin levels were lower. CONCLUSIONS: The IL-17 family of cytokines may suppress or promote tumor growth. There seems to be some balance between the effects of IL-17A and IL-17E. The role of increased levels of IL-17E needs further investigation to understand its role in the pathobiology of MM.

Does thrombopoiesis in multiple myeloma patients depend on the stage of the disease?

PURPOSE: Infiltration of the bone marrow by neoplastic plasmocytes in multiple myeloma (MM) patients might impair megakaryocytopoiesis. The aim of the study was to evaluate stage-dependent platelet count (PLT) and thrombopoietin (TPO) concentration in comparison to the control group. We also wanted to establish whether TPO might be recognized as a marker of the stage of the disease. MATERIAL/METHODS: The study group consisted of 41 patients (mean age 67.7) with newly diagnosed MM prior to treatment and categorized according to the Durie and Salmon diagnostic classification. The control group consisted of 30 healthy subjects (mean age 65.5). PLT, WBC, RBC and Hb were measured with the use of the haematological analyser. TPO was assayed with the use of ELISA and albumin with the use of the immunonephelometry method. The number of plasma cells in the bone marrow was evaluated in bone marrow smears under light microscopy. RESULTS: PLT was not statistically different as compared the control groups, but was stage-dependent. Thrombocytopenia was observed in the III stage of MM. TPO median was significantly higher in study group than in healthy subjects and it was increasing considerably with the stage of the disease. TPO concentration was negatively correlated with albumin and PLT. AUC for TPO was 0.9764. The number of plasma cells in the bone marrow was considerably increasing with the stage of the disease. CONCLUSIONS: PLT and TPO in MM patients were stage-dependent. Elevated TPO concentration in MM patients might be an unfavourable marker of the stage of the disease.