[en] Progression of multiple myeloma (MM) is largely dependent on the bone marrow (BM) microenvironment wherein communication through different factors including extracellular vesicles takes place. This cross-talk not only leads to drug resistance but also to the development of osteolysis. Targeting vesicle secretion could therefore simultaneously ameliorate drug response and bone disease. In this paper, we examined the effects of MM exosomes on different aspects of osteolysis using the 5TGM1 murine model. We found that 5TGM1 sEVs, or 'exosomes', not only enhanced osteoclast activity, they also blocked osteoblast differentiation and functionality in vitro. Mechanistically, we could demonstrate that transfer of DKK-1 led to a reduction in Runx2, Osterix, and Collagen 1A1 in osteoblasts. In vivo, we uncovered that 5TGM1 exosomes could induce osteolysis in a similar pattern as the MM cells themselves. Blocking exosome secretion using the sphingomyelinase inhibitor GW4869 not only increased cortical bone volume, but also it sensitized the myeloma cells to bortezomib, leading to a strong anti-tumor response when GW4869 and bortezomib were combined. Altogether, our results indicate an important role for exosomes in the BM microenvironment and suggest a novel therapeutic target for anti-myeloma therapy.
Heusschen, R. et al. Molecular mechanisms, current management and next generation therapy in myeloma bone disease. Leuk. Lymphoma 59, 14–28 (2018).
Ring, E. S., Lawson, M. A., Snowden, J. A., Jolley, I. & Chantry, A. D. New agents in the treatment of myeloma bone disease. Calcif. Tissue Int. 102, 196–209 (2017).
Moreau, P. et al. Multiple myeloma: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann. Oncol. 28(April 2017), iv52–iv61 (2017).
Lemaire, M. et al. The microenvironment and molecular biology of the multiple myeloma tumor. Adv. Cancer Res. 110, 19–42 (2011).
Zijlstra, A. & Di Vizio, D. Size matters in nanoscale communication. Nat. Cell Biol. 20, 228–230 (2018).
De Veirman, K. et al. Induction of miR-146a by multiple myeloma cells in mesenchymal stromal cells stimulates their pro-tumoral activity. Cancer Lett. 377, 17–24 (2016).
Wang, J. et al. Bone marrow stromal cell – derived exosomes as communicators in drug resistance in multiple myeloma cells. Blood J. 124, 555–567 (2014).
Wang, J. et al. Multiple myeloma exosomes establish a favourable bone marrow microenvironment with enhanced angiogenesis and immunosuppression. J. Pathol. 239, 162–173 (2016).
Wang, J. et al. The bone marrow microenvironment enhances multiple myeloma progression by exosome-mediated activation of myeloid-derived suppressor cells. Oncotarget 6, 43992–44004 (2015).
Wang, J. et al. Extracellular vesicle cross-talk in the bone microenvironment: implications in multiple myeloma marrow. Oncotarget. 7, 38927–38945 (2016).
Zahoor, M. et al. Hypoxia promotes IL-32 expression in myeloma cells, and high expression is associated with poor survival and bone loss. Blood Adv. 1, 2656–2666 (2017).
Raimondi, L. et al. Involvement of multiple myeloma cell-derived exosomes in osteoclast differentiation. Oncotarget 6, 13772–13789 (2015).
Muller, J. et al. Maternal embryonic leucine zipper kinase inhibitor OTSSP167 has preclinical activity on multiple myeloma bone disease. Haematologica 103, 1359–1368 (2018).
Heusschen, R. et al. SRC kinase inhibition with saracatinib limits the development of osteolytic bone disease in multiple myeloma. Oncotarget 7, 30712–30729 (2016).
Kowal, J. et al. Proteomic comparison defines novel markers to characterize heterogeneous populations of extracellular vesicle subtypes. Proc. Natl Acad. Sci. USA 113, E968–E977 (2016).
Peinado, H. et al. Melanoma exosomes educate bone marrow progenitor cells toward a pro-metastatic phenotype through MET. Nat. Med. 18, 883–891 (2012).
Tadokoro, H., Umezu, T., Ohyashiki, K., Hirano, T. & Ohyashiki, J. H. Exosomes derived from hypoxic leukemia cells enhance tube formation in endothelial cells. J. Biol. Chem. 288, 34343–34351 (2013).
Umezu, T., Ohyashiki, K., Kuroda, M. & Ohyashiki, J. H. Leukemia cell to endothelial cell communication via exosomal miRNAs. Oncogene 32, 2747–2755 (2013).
Kumar, B. et al. Acute myeloid leukemia transforms the bone marrow niche into a leukemia-permissive microenvironment through exosome secretion. Leukemia 32, 575–587 (2018).
Garrett, I. R., Dallas, S., Radl, J. & Mundy, G. R. A murine model of human myeloma bone disease. Bone 20, 515–520 (1997).
Wang, D. et al. Isolation and characterization of MC3T3-E1 preosteoblast subclones with distinct in vitro and in vivo differentiation/mineralization potential. J. Bone Miner. Res. 14, 893–903 (1999).
Huelsken, J. & Birchmeier, W. New aspects of Wnt signaling pathways in higher vertebrates. Curr. Opin. Genet. Dev. 11, 547–553 (2001).
Trajkovic, K. et al. Ceramide triggers budding of exosome vesicles into multivesicular endosomes. Sci. (80). 319, 1244–1247 (2008).
McDonald, M. M., Fairfield, H., Falank, C. & Reagan, M. R. Adipose, bone, and myeloma: contributions from the microenvironment. Calcif. Tissue Int. 100, 433–448 (2017).
Kim, Y. et al. Influencing the Wnt signaling pathway in multiple myeloma. Anticancer Res. 31, 725–730 (2011).
Heath, D. J. et al. Inhibiting dickkopf-1 (Dkkl) removes suppression of bone formation and prevents the development of osteolytic bone disease in multiple myeloma. J. Bone Miner. Res. 24, 425–436 (2009).
Vuckovic, S. et al. The cationic small molecule GW4869 is cytotoxic to high phosphatidylserine-expressing myeloma cells. Br. J. Haematol. 177, 423–440 (2017).
Dinkins, M. B., Dasgupta, S., Wang, G., Zhu, G. & Bieberich, E. Exosome reduction in vivo is associated with lower amyloid plaque load in the 5XFAD mouse model of Alzheimer’s disease. Neurobiol. Aging 35, 1792–1800 (2014).
Essandoh et al. Blockade of exosome generation with GW4869 dampens the sepsis-induced inflammation and cardiac dysfunction. Biochim Biophys. Acta - Mol. Basis Dis. 1852, 2362–2371 (2015).
Nagashima, S. et al. Hepatitis E virus egress depends on the exosomal pathway, with secretory exosomes derived from multivesicular bodies. J. Gen. Virol. 95, 2166–2175 (2014).
Matsumoto, A. et al. Accelerated growth of B16BL6 tumor in mice through efficient uptake of their own exosomes by B16BL6 cells. Cancer Sci. 108, 1803–1810 (2017).
