Role of FBXW2 in explant culture of bovine periosteum-derived cells

Osteoporosis and bone fracture decrease quality of life. Bone regeneration is a notable technique for osteoporosis treatment. A previous study reported that F-box and WD-40 domain-containing protein 2 (FBXW2) and osteocalcin have the same shape in the periosteum after 5 weeks. However, the osteoblastic functions of FBXW2 are not clear. In this study, double fluorescent immunostaining revealed a small amount of osteocalcin in the area of FBXW2 aggregation at 1 week, periosteal cells, and osteocalcin pushed toward the edge of periosteum, and, apart from FBXW2 tubes at 2 weeks, multilayered periosteum-derived cells at 3 weeks and sticking of osteocalcin in the periosteum with cells at 4 weeks. At 5 weeks, FBXW2 disappeared at the root of periosteum-derived cells, while osteocalcin and cells remained. Based on these results, it is hypothesized that FBXW2 maintains tissue shapes and prevents escape of inner periosteal cells, and the disappearance of FBXW2 causes migration of periosteum-derived cells out of the periosteum along with osteocalcin. Furthermore, FBXW2 may play a role in dynamic tissue remodeling and bone formation.