New York University School of Medicine, 550 First Ave., New York, NY 10016, USA.
FASEB J. 2013 Sep;27(9):3446-54. doi: 10.1096/fj.13-231233. Epub 2013 May 16.
Multiple myeloma (MM) is characterized by osteolytic bone lesions with uncoupled bone remodeling. In this study, we examined the effects of adenosine and its receptors (A1R, A2AR, A2BR, and A3R) on osteoblast and osteoclast differentiation of cells derived from patients with MM and healthy control subjects. Mesenchymal stem cells and bone marrow-derived mononuclear cells were isolated from bone marrow and differentiated into osteoblasts and osteoclasts, respectively. A1R antagonist rolofylline and A2BR agonist BAY60-6583 inhibit osteoclast differentiation of cells from patients with MM in a dose-dependent manner, as shown by TRAP staining (IC50: 10 and ∼10 nM, respectively). BAY60-6583 and dipyridamole, a nucleoside transport inhibitor, stimulate osteoblast differentiation of cells from patients with MM, as measured by ALP activity at d 14 and Alizarin Red staining at d 21 (by 1.57±0.03- and 1.71±0.45-fold, respectively), which can be blocked by A2BR antagonist MRS1754. Consistently, real-time PCR showed a significant increase of mRNA of osteocalcin and osterix at d 14. The effect of adenosine and its receptors is consistent in patients with MM and healthy subjects, suggesting an intrinsic mechanism that is important in both MM bone metabolism and normal physiology. Furthermore, the effect of dipyridamole on osteoblast differentiation is diminished in both A2BR- and CD39-knockout mice. These results indicate that adenosine receptors may be useful targets for the treatment of MM-induced bone disease.
多发性骨髓瘤（MM）的特征是破骨细胞性骨病变和骨重建脱耦联。在这项研究中，我们研究了腺苷及其受体（A1R、A2AR、A2BR 和 A3R）对 MM 患者和健康对照者来源的细胞成骨细胞和破骨细胞分化的影响。从骨髓中分离间充质干细胞和骨髓源性单核细胞，分别分化为成骨细胞和破骨细胞。A1R 拮抗剂罗洛非林和 A2BR 激动剂 BAY60-6583 以剂量依赖的方式抑制 MM 患者来源细胞的破骨细胞分化，如 TRAP 染色所示（IC50：分别为 10 和 ∼10 nM）。BAY60-6583 和双嘧达莫，一种核苷转运抑制剂，刺激 MM 患者来源细胞的成骨细胞分化，如第 14 天的碱性磷酸酶活性和第 21 天的茜素红染色所示（分别增加 1.57±0.03-和 1.71±0.45 倍），这可以被 A2BR 拮抗剂 MRS1754 阻断。同样，实时 PCR 显示第 14 天骨钙素和骨桥蛋白的 mRNA 显著增加。腺苷及其受体的作用在 MM 患者和健康受试者中是一致的，表明这是一种内在机制，在 MM 骨代谢和正常生理中都很重要。此外，双嘧达莫对成骨细胞分化的作用在 A2BR 和 CD39 敲除小鼠中均减弱。这些结果表明，腺苷受体可能是治疗 MM 诱导的骨病的有用靶点。
