Open AccessErythroblast apoptosis and microenvironmental iron restriction trigger anemia in the VK*MYC model of multiple myeloma
Author(s) -
Jessica Bordini,
Maria Teresa Sabrina Bertilaccio,
Maurilio Ponzoni,
Isabella Fermo,
Marta Chesi,
P. Leif Bergsagel,
Clara Camaschella,
Alessandro Campanella
Publication year - 2015
Publication title -
haematologica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.782
H-Index - 142
eISSN - 1592-8721
pISSN - 0390-6078
DOI - 10.3324/haematol.2014.118000
Subject(s) - bone marrow , multiple myeloma , anemia , hepcidin , clone (java method) , erythropoietin , immunology , cancer research , transferrin receptor , biology , bone marrow failure , inflammation , medicine , haematopoiesis , transferrin , microbiology and biotechnology , endocrinology , stem cell , dna , genetics
Multiple myeloma is a malignant disorder characterized by bone marrow proliferation of plasma cells and by overproduction of monoclonal immunoglobulin detectable in the sera (M-spike). Anemia is a common complication of multiple myeloma, but the underlying pathophysiological mechanisms have not been completely elucidated. We aimed to identify the different determinants of anemia using the Vk*MYC mouse, which spontaneously develops an indolent bone marrow localized disease with aging. Affected Vk*MYC mice develop a mild normochromic normocytic anemia. We excluded the possibility that anemia results from defective erythropoietin production, inflammation or increased hepcidin expression. Mature erythroid precursors are reduced in Vk*MYC bone marrow compared with wild-type. Malignant plasma cells express the apoptogenic receptor Fas ligand and, accordingly, active caspase 8 is detected in maturing erythroblasts. Systemic iron homeostasis is not compromised in Vk*MYC animals, but high expression of the iron importer CD71 by bone marrow plasma cells and iron accumulation in bone marrow macrophages suggest that iron competition takes place in the local multiple myeloma microenvironment, which might contribute to anemia. In conclusion, the mild anemia of the Vk*MYC model is mainly related to the local effect of the bone marrow malignant clone in the absence of an overt inflammatory status. We suggest that this reproduces the initial events triggering anemia in patients.