ROR2 Promoter Methylation Change in Osteoblastic Differentiation of Mesenchymal Stem Cells

• Main Authors: Maryam Mahmoodinia Maymand, Majid Farshdousti Hagh, Saeed Kaviani, Masood Soleimani, Gorbanali Tarfiei, Mehrdad Noruzinia, Pascal Pujol
• Format: Article
• Language: English
• Published: Royan Institute (ACECR), Tehran 2011-01-01
• Series: Cell Journal
• Subjects: Mesenchymal Stem Cell; Methylation; ROR2; Osteoblast Differentiation; Epigenetics
• Online Access: http://celljournal.org/library/upload/article/af_2254374344252633322734436365324423547224Tarifi1.pdf
• ISSN: 2228-5806; 2228-5814

Objective: Osteoblasts arise from multipotent mesenchymal stem cells (MSCs) presentin the bone marrow stroma and undergo further differentiation to osteocytes or bone cells.Many factors such as proteins present in the Wnt signaling pathway affect osteoblastdifferentiation. ROR2 is an orphan tyrosine kinase receptor that acts as a co-receptor inthe non-canonical Wnt signaling pathway. However, ROR2 has been shown to be regulatedby both canonical and non-canonical Wnt signaling pathways. ROR2 expressionincreases during differentiation of MSCs to osteoblasts and then decreases as cells differentiateto osteocytes. On the other hand, research has shown that ROR2 changesMSC fate towards osteoblasts by inducing osteogenic transcription factor OSTERIX. Herewe speculated whether ROR2 gene expression regulation during osteoblastogenesis isepigenetically determined.Materials and Methods: MSCs from bone marrow were isolated, expanded and characterizedin vitro according to standard procedures. ROR2 promoter methylation status wasdetermined using methylation specific PCR in a multipotent state and during differentiationto osteoblasts.Results: We determined that the demethylation process in ROR2 promoter occurs duringthe differentiation process. The process of demethylation begins at day 8 and continuesuntil 21 days of differentiation.Conclusion: This result is in concordance with previous works on the role of ROR2 onosteoblast differentiation, which have shown an upregulation of ROR2 expression duringthis process.