title: Mechanisms of stem cell osteogenic differentiation on TiO2 nanotubes.
abstract: TiO2 nanotubes could stimulate osteogenic differentiation of stem cells, but the molecular mechanisms underlying the interactions between nanotubes and stem cells remain unclear. In this study, we investigated the response of bone marrow stromal cells to nanotubes of different diameters using microarray-based bioinformatics approach. Gene ontology (GO) and GO enrichment network analysis indicated that larger TiO2 nanotubes were more potent than smaller nanotubes in inducing the expression of genes involved in cell proliferation, differentiation, and immune responses, and inhibiting that of genes responsible for cell adhesion. The analysis of the signaling network containing significantly affected genes suggested that Na(+)/K(+) transporting ATPases ATP1A2 (alpha 2 polypeptide) and ATP1A3 (alpha 3 polypeptide), and MAP3K11 (mitogen-activated protein kinase kinase kinase 11) were important for inducing osteogenic differentiation of bone marrow stromal cells without additional osteogenic stimuli. The upregulation of the ATP1A2 and MAP3K11 genes confirmed by real-time PCR indicates that the response of bone marrow stromal cells to nanotube cues may be mediated by the pathways previously implicated in transducing mechanical stress signals. Our results revealed some molecular mechanisms by which TiO2 nanotubes may direct osteogenic differentiation of stem cells.
authors.affiliation: Department of Prosthodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China.
authors.forename: Weiqiang
authors.initials: W
authors.lastname: Yu
authors.affiliation: Department of Prosthodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Qian
authors.affiliation: Department of Prosthodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China.
authors.forename: Xinquan
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Department of Prosthodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China. Electronic address: qiang1951@126.com.
authors.forename: Fuqiang
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Department of Prosthodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China. Electronic address: Wengwm1961@126.com.
authors.forename: Weimin
authors.initials: W
authors.lastname: Weng
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D008297:Male; D008855:Microscopy, Electron, Scanning; D043942:Nanotubes; D010012:Osteogenesis; D051381:Rats; D017208:Rats, Wistar; D013234:Stem Cells / Q000166:cytology*; D014025:Titanium
chemical_list: C009495:titanium dioxide; D014025:Titanium
keywords: Molecular mechanism; Osteogenic differentiation; TiO(2) nanotubes