Hepcidin is the principal iron-regulatory hormone and a pathogenic factor in anemia of inflammation. Patients with multiple myeloma (MM) frequently present with anemia. We showed that MM patients had increased serum hepcidin, which inversely correlated with hemoglobin, suggesting that hepcidin contributes to MMrelated anemia. Searching for hepcidininducing cytokines in MM, we quantified the stimulation of hepcidin promoterluciferase activity in HuH7 cells by MM sera. MM sera activated the hepcidin promoter significantly more than did normal sera. We then examined the role of bone morphogenetic proteins (BMPs) and interleukin-6 (IL-6), the major transcriptional regulators of hepcidin. Mutations in both BMP-responsive elements abrogated the activation dramatically, while mutations in the IL-6-responsive signal transducer and activator of transcription 3-binding site (STAT3-BS) had only a minor effect. Cotreatment with anti-BMP-2/4 or noggin-Fc blocked the promoter induction with all MM sera, anti-IL-6 blocked it with a minority of sera, whereas anti-BMP-4, -6, or -9 antibodies had no effect. BMP-2-immunodepleted MM sera had decreased promoter stimulatory capacity, and BMP-2 concentrations in MM sera were significantly higher than in normal sera. Our results demonstrate that BMP-2 is a major mediator of the hepcidin stimulatory activity of MM sera. (Blood. 2010;116(18):3635-3644) IntroductionMultiple myeloma (MM) is a malignant plasma cell disorder that accounts for approximately 10% of all hematologic cancers. 1 The disease is characterized by monoclonal proliferation of plasma cells together with overproduction of a monoclonal antibody, 2 often accompanied by anemia, hypercalcemia, renal insufficiency, or bone lesions. 3 Approximately 97% of MM patients develop anemia during the course of their illness, and 70% are anemic at diagnosis. The anemia is usually normocytic/normochromic, 4 serum-iron levels are normal to low, serum ferritin is high, and hemosiderin is prominent in bone marrow macrophages. 5 This suggests than iron release from reticuloendothelial macrophages is impaired, consistent with anemia of inflammation. 6 The main mediator of anemia of inflammation is the ironregulatory hormone, hepcidin. Hepcidin is produced by hepatocytes and acts on the iron exporter, ferroportin. Binding of hepcidin to ferroportin induces the internalization and degradation of ferroportin, thereby preventing cellular iron efflux and causing retention of iron, mainly inside enterocytes, macrophages, and hepatocytes. 7 Pathologic induction of hepcidin by inflammation causes hypoferremia, restricting the iron supply for erythropoiesis and, eventually, causing anemia. The interleukin-6 (IL-6)-hepcidin axis was shown to be important for inflammation-related hypoferremia. 8 However, in chronic inflammation, IL-6-independent pathways may also induce hepcidin mRNA. 9 Recently, 2 studies described the involvement of hepcidin in anemia of MM in humans. We reported that patients with stage III MM (n ϭ 44) at diagnosis had higher urinar...

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Purpose: Hepcidin is a liver-produced peptide implicated in the anemia of inflammation. Because interleukin (IL)-6 is a potent inducer of hepcidin expression and its levels are elevated in multiple myeloma, we studied the role of hepcidin in the anemia of multiple myeloma. Experimental Design: Urinary hepcidin and serum levels of IL-6, ferritin, C-reactive protein, tumor necrosis factor-a, and IL-1h were studied in newly diagnosed myeloma patients. In vitro hepcidin induction assay was assessed by real-time PCR assay. Results: Pretreatment urinary hepcidin levels in 44 patients with stage III multiple myeloma were 3-fold greater than normal controls. In the subset of multiple myeloma patients without renal insufficiency (n = 27), a marked inverse correlation was seen between hemoglobin at diagnosis and urinary hepcidin level (P = 0.014) strongly supporting a causal relationship between up-regulated hepcidin expression and anemia. The urinary hepcidin also significantly (P < 0.05) correlated with serum ferritin and C-reactive protein, whereas its correlation with serum IL-6 levels was of borderline significance (P = 0.06). Sera from 14 multiple myeloma patients, with known elevated urinary hepcidin, significantly induced hepcidin mRNA in the Hep3B cells, whereas normal sera had no effect. For 10 patients, the ability of anti-IL-6 and anti-IL-6 receptor antibodies to prevent the serum-induced hepcidin RNA was tested. In 6 of these patients, hepcidin induction was abrogated by the anti-IL-6 antibodies, but in the other 4 patients, the neutralizing antibodies had no effect. Conclusions: These results indicate hepcidin is up-regulated in multiple myeloma patients by both IL-6-dependent and IL-6-independent mechanisms and may play a role in the anemia of multiple myeloma.

The costs and effectiveness of both the test and no-test strategies are very similar even when there is a small probability of mutation. Current guidelines, which can be used by insurance companies to refuse coverage, could deny some women a cost-effective approach. Further research to decrease the frequency of inconclusive results could improve the cost-effectiveness of this test.