title: Wnt/β-catenin signaling in bone marrow niche.
abstract: The bone marrow (BM) niche is a specific physiological environment for hematopoietic and non-hematopoietic stem cells (HSCs). Several signaling pathways (including Wnt/β-catenin) regulate various aspects of stem cell growth, function and death in the BM niche. In addition, the canonical Wnt pathway is crucial for directing self-renewal and differentiation as important mechanisms in many types of stem cells. We review the role of the Wnt/β-catenin pathway in the BM niche and its importance in stem cells. Relevant literature was identified by a PubMed search (1997-2014) of English-language literature by using the following keywords: BM niche, Wnt/β-catenin signaling, osteoblast, osteoclast and bone disease. The Wnt/β-catenin pathway regulates the stability of the β-catenin proto-oncogene. The stabilized β-catenin then translocates to the nucleus, forming a β-catenin-TCF/LEF complex regulating the transcription of specific target genes. Stem cells require β-catenin to mediate their response to Wnt signaling for maintenance and transition from the pluripotent state during embryogenesis. In adult stem cells, Wnt signaling functions at various hierarchical levels to contribute to the specification of the diverse tissues. Aberrant Wnt/β-catenin signaling and its downstream transcriptional regulators are observed in several malignant stem cells and human cancers. Because Wnt signaling can maintain stem cells and cancer cells, the ability to modulate the Wnt pathway either positively or negatively may be of therapeutic relevance. The controlled activation of Wnt signaling might allow us to enhance stem and progenitor cell activity when regeneration is needed.
authors.affiliation: Health Research Institute, Research Center of Thalassemia & Hemoglobinopathy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Ahmadzadeh
authors.affiliation: Health Research Institute, Research Center of Thalassemia & Hemoglobinopathy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Norozi
authors.affiliation: Department of Biochemistry and Hematology, Faculty of Medicine, Semnan University of Medical Sciences, Semnan, Iran.
authors.forename: Saeid
authors.initials: S
authors.lastname: Shahrabi
authors.affiliation: Health Research Institute, Research Center of Thalassemia & Hemoglobinopathy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Shahjahani
authors.affiliation: Health Research Institute, Research Center of Thalassemia & Hemoglobinopathy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran. najmaldinsaki@gmail.com.
authors.forename: Najmaldin
authors.initials: N
authors.lastname: Saki
mesh_terms: D000818:Animals; D001847:Bone Diseases / Q000473:pathology; D001853:Bone Marrow / Q000378:metabolism*; D016922:Cellular Senescence; D006801:Humans; D007938:Leukemia / Q000473:pathology; D000090063:Proto-Oncogene Mas; D055153:Stem Cell Niche; D060449:Wnt Signaling Pathway
keywords: Bone marrow niche; Cellular senescence; Osteoblast; Osteoclast; Wnt/β-catenin