title: Angiopoietins in the bone marrow microenvironment of acute lymphoblastic leukemia.
abstract: OBJECTIVE
  Angiogenesis have implications in leukemia biology. Angiopoietin 1 (Ang 1) is an angiogenic cytokine which is essential in survival and proliferation of endothelial cells. Angiopoietin 2 (Ang 2) promotes dissociation of pericytes and increases vascular permeability and stromal derived factor 1 alpha (SDF 1α) which is a key player in stem cell traffic in the bone marrow (BM), has stimulating effects on angiogenesis as well. Here, we investigated the role of the leukemic BM microenvironment and specifically, the role of SDF 1α-CXCR4 and Ang 1/Ang 2-Tie 2 axes.
  
  
  METHODS
  Here, Ang 1, Ang 2, and SDF 1α levels were measured in the BM plasma and in supernatants of mesenchymal stem/stromal cells (MSCs) of patients with ALL and compared with those of healthy controls.
  
  
  RESULTS
  The results showed that at diagnosis, BM plasma levels of Ang 1 and SDF 1α were significantly low and Ang 2 was high when compared to control values. Remission induction was associated with an increase in Ang 1/Ang 2 ratio and SDF levels in BM plasma.
  
  
  CONCLUSIONS
  The results suggest that BM microenvironment and leukemic cell-stroma interaction influences the secretion of Ang 1, 2 and SDF 1α, thus, may affect both angiogenesis, homing and mobilization of leukemic blasts.
authors.affiliation: a Deparment of Pediatric Hematology/Oncology , Ankara Childrens' Hematology/Oncology Education and Research Hospital , Ankara , Turkey.
authors.forename: Neslihan
authors.initials: N
authors.lastname: Karakurt
authors.affiliation: a Deparment of Pediatric Hematology/Oncology , Ankara Childrens' Hematology/Oncology Education and Research Hospital , Ankara , Turkey.
authors.forename: Tekin
authors.initials: T
authors.lastname: Aksu
authors.affiliation: b Deparment of Pediatric Hematology/Oncology, Stem Cell Laboratory , Ankara Childrens' Hematology/Oncology Education and Research Hospital , Ankara , Turkey.
authors.forename: Yasin
authors.initials: Y
authors.lastname: Koksal
authors.affiliation: a Deparment of Pediatric Hematology/Oncology , Ankara Childrens' Hematology/Oncology Education and Research Hospital , Ankara , Turkey.
authors.forename: Nese
authors.initials: N
authors.lastname: Yarali
authors.affiliation: a Deparment of Pediatric Hematology/Oncology , Ankara Childrens' Hematology/Oncology Education and Research Hospital , Ankara , Turkey.
authors.forename: Bahattin
authors.initials: B
authors.lastname: Tunc
authors.affiliation: c Department of Pediatric Bone Marrow Transplantation , Hacettepe School of Medicine Ihsan Dogramaci Childrens' Hospital , Ankara , Turkey.
authors.forename: Duygu
authors.initials: D
authors.lastname: Uckan-Cetinkaya
authors.affiliation: b Deparment of Pediatric Hematology/Oncology, Stem Cell Laboratory , Ankara Childrens' Hematology/Oncology Education and Research Hospital , Ankara , Turkey.
authors.forename: Meltem
authors.initials: M
authors.lastname: Ozguner
mesh_terms: D042682:Angiopoietins / Q000378:metabolism*; D001853:Bone Marrow / Q000378:metabolism*; D002648:Child; D006801:Humans; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics*; D011446:Prospective Studies; D059016:Tumor Microenvironment
chemical_list: D042682:Angiopoietins
keywords: Acute lymphoblastic leukemia; Ang 1/Ang 2 ratio; Angiopoietins; Bone marrow microenvironment; Children; SDF 1α