title: Microenvironmental targeting of Wnt/beta-catenin signals for hematopoietic stem cell regulation.
abstract: BACKGROUND
  Microenvironment has emerged as crucial element in the regulation of hematopoietic stem cells (HSCs) in the stem cell niche. Recent studies have demonstrated that Wnt/beta-catenin signals are clearly involved in the stem cell niche, raising the possibility that the hematopoietic microenvironment is a potential target for stem cell therapy.
  
  
  METHODS
  In this review, the biological outcomes of Wnt/beta-catenin signals on HSC activity are summarized in various study models and potential reasons for discrepancies are discussed. Evidence for the microenvironmental targeting of Wnt/beta-catenin signals and studies that verify this concept is summarized.
  
  
  RESULTS
  We show that distinct effects of Wnt/beta-catenin on HSCs can be caused depending on their target of activation in the hematopoietic microenvironment. We show stromal targeting of Wnt/beta-catenin signals and cross-talk with notch signals in the niche during bone marrow regeneration enhancing the self-renewal of HSCs.
  
  
  CONCLUSIONS
  The identification of stroma-mediated Wnt/beta-catenin effects now allows the integration of discrepancies in previously reported findings and suggests that the stromal targeting of wnt/beta-catenin signals could serve as a potential therapeutic strategy for activating a stem cell niche for the efficient regeneration of HSCs.
authors.affiliation: Catholic High-Performance Cell Therapy Center, Division of Regenerative Medicine, The Catholic University of Korea, College of Medicine, 505, Banpo-Dong, Seocho-Ku, Seoul, Republic of Korea. iho@catholic.ac.kr
authors.forename: Il-Hoan
authors.initials: IH
authors.lastname: Oh
mesh_terms: D000818:Animals; D002450:Cell Communication; D049109:Cell Proliferation; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006801:Humans; D012038:Regeneration; D015398:Signal Transduction; D055153:Stem Cell Niche; D017154:Stromal Cells / Q000378:metabolism; D051153:Wnt Proteins / Q000378:metabolism*; D051176:beta Catenin / Q000378:metabolism*
chemical_list: D051153:Wnt Proteins; D051176:beta Catenin