Dataset Information

Reprogrammed marrow adipocytes: an unexpected role in the genesis of myeloma-induced bone disease

ABSTRACT: Multiple myeloma is characterized by osteolytic lesions caused by osteoclast-mediated bone resorption and reduced bone formation. A unique feature of myeloma is a failure of bone healing following successful treatment. Identification of increased adipocyte numbers in marrow of successfully treated patients led us to demonstrate that normal marrow adipocytes, when co-cultured with myeloma cells, are reprogrammed and produce adipokines that activate osteoclastogenesis and suppress osteoblastogenesis. These adipocytes have reduced expression of peroxisome proliferator-activated receptor γ (PPARγ) mediated by recruitment of polycomb-repressive complex 2 (PRC2) via specificity protein 1, which modifies PPARγ promoter methylation at trimethyl lysine-27 histone H3. We confirmed the importance of PPARγ methylation by demonstrating that adipocyte-specific knockout of EZH2, a member of the PRC2, prevents adipocyte reprogramming and reverses bone changes in vivo. These results define a heretofore unrecognized role for adipocytes in genesis of myeloma-associated bone disease and that reversal of adipocyte reprogramming has therapeutic implications.

ORGANISM(S): Homo sapiens

PROVIDER: GSE113295 | GEO | 2018/04/18

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:The unique properties of the bone marrow allow for migration and proliferation of multipl myeloma (MM) cells, while also providing the perfect environment for development of quiescent, drug-resistant MM cell clones. Bone marrow adipocytes (BMAds), which have recently been identified as important contributors to systemic adipokine levels, bone strength, hematopoiesis, and progression of metastatic and primary bone marrow cancers, such as MM. Recent studies in myeloma suggest that BMAds can be reprogrammed by tumor cells to contribute to myeloma-induced bone disease, and reciprocally, BMAds support MM cells in vitro. Importantly, most data investigating BMAds have been generated using adipocytes derived by differentiating bone marrow-derived mesenchymal stromal cells (MSCs) into adipocytes in vitro using adipogenic media, due to the extreme technical challenges associated with isolating and culturing primary adipocytes. However, if studies could be performed with primary adipocytes, they likely will recapitulate in vivo biology better than MSC-derived adipocyte, as the differentiation process is artificial and differs from in vivo differentiation, and progenitor cell(s) of the primary BMAd may not be the same as the MSCs precursors used for adipogenic differentiation in vitro. Therefore, we developed and refined three methods for culturing primary BMAds (pBMAds): 2D coverslips, 2D transwells, and 3D silk scaffolds, all of which can be cultured alone or with MM cells to investigate bidirectional tumor-host signaling. To develop an in vitro model with a tissue-like structure to mimic the bone marrow microenvironment, we developed the first 3D, tissue engineered model utilizing pBMAds derived from human bone marrow. We found that pBMAds, which are extremely fragile, can be isolated and stably cultured in 2D for 10 days and in 3D for short term (~2 weeks) or long term (1 month) in vitro. To investigate the relationship between pBMAds and myeloma, MM cells can be added to investigate physical relationships through confocal imaging and soluble signaling molecules via mass spectrometry. In sum, we developed three in vitro cell culture systems to study primary bone marrow adipocytes and myeloma cells, which could be adapted to investigate many diseases and biological processes involving the bone marrow, including other bone-homing tumor types.

Dataset Information

Reprogrammed marrow adipocytes: an unexpected role in the genesis of myeloma-induced bone disease

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure