SaOS2 Osteosarcoma Cells as an In Vitro Model for Studying the Transition of Human Osteoblasts to Osteocytes
- 12 June 2014
- journal article
- Published by Springer Science and Business Media LLC in Calcified Tissue International
- Vol. 95 (2), 183-193
- https://doi.org/10.1007/s00223-014-9879-y
Abstract
The central importance of osteocytes in regulating bone homeostasis is becoming increasingly apparent. However, the study of these cells has been restricted by the relative paucity of cell line models, especially those of human origin. Therefore, we investigated the extent to which SaOS2 human osteosarcoma cells can differentiate into osteocyte-like cells. During culture under the appropriate mineralising conditions, SaOS2 cells reproducibly synthesised a bone-like mineralised matrix and temporally expressed the mature osteocyte marker genes SOST, DMP1, PHEX and MEPE and down-regulated expression of RUNX2 and COL1A1. SaOS2 cells cultured in 3D collagen gels acquired a dendritic morphology, characteristic of osteocytes, with multiple interconnecting cell processes. These findings suggest that SaOS2 cells have the capacity to differentiate into mature osteocyte-like cells under mineralising conditions. PTH treatment of SaOS2 cells resulted in strong down-regulation of SOST mRNA expression at all time points tested. Interestingly, PTH treatment resulted in the up-regulation of RANKL mRNA expression only at earlier stages of differentiation. These findings suggest that the response to PTH is dependent on the differentiation stage of the osteoblast/osteocyte. Together, our results demonstrate that SaOS2 cells can be used as a human model to investigate responses to osteotropic stimuli throughout differentiation to a mature osteocyte-like stage.Matthew Prideaux, Asiri R. Wijenayaka, Duminda D. Kumarasinghe, Renee T. Ormsby, Andreas Evdokiou, David M. Findlay, Gerald J. AtkinKeywords
This publication has 54 references indexed in Scilit:
- Cell line IDG-SW3 replicates osteoblast-to-late-osteocyte differentiation in vitro and accelerates bone formation in vivoJournal of Bone and Mineral Research, 2011
- Sost down‐regulation by mechanical strain in human osteoblastic cells involves PGE2 signaling via EP4FEBS Letters, 2011
- Sclerostin is a locally acting regulator of late-osteoblast/preosteocyte differentiation and regulates mineralization through a MEPE-ASARM-dependent mechanismJournal of Bone and Mineral Research, 2011
- Functional and association analysis of frizzled 1 (FZD1) promoter haplotypes with femoral neck geometryBone, 2010
- Identification of differentially expressed genes between osteoblasts and osteocytesBone, 2009
- Runx2, p53, and pRB status as diagnostic parameters for deregulation of osteoblast growth and differentiation in a new pre‐chemotherapeutic osteosarcoma cell line (OS1)Journal of Cellular Physiology, 2009
- Elevated expression of Runx2 as a key parameter in the etiology of osteosarcomaMolecular Biology Reports, 2008
- Mechanism by which MLO-A5 Late Osteoblasts/Early Osteocytes Mineralize in Culture: Similarities with Mineralization of Lamellar BoneCalcified Tissue International, 2006
- Loss of DMP1 causes rickets and osteomalacia and identifies a role for osteocytes in mineral metabolismNature Genetics, 2006
- Analysis of Relative Gene Expression Data Using Real-Time Quantitative PCR and the 2−ΔΔCT MethodMethods, 2001