title: [Apoptosis and differentiation induced by sodium selenite combined with all-trans retinoic acid (ATRA) in NB4 cells].
abstract: OBJECTIVE
  To study the effects of low dose sodium selenite combined with all-trans retinoic acid (ATRA) on apoptosis and differentiation of human acute promyelocytic leukemia (APL) NB4 cells.
  
  
  METHODS
  Apo-ptosis was detected by translocation of phosphatidylserine (PS) with a Annexin-V kit and DNA fragmentation by agarose gel electrophoresis analysis, cell differentiation was studied by flow cytometry of CD(11b) expression and NBT reduction assay.
  
  
  RESULTS
  Five micromol/L sodium selenite or 0.1 micromol/L ATRA alone could not induce apoptosis of NB4 cells within 48 hours. However, combination of the two drugs at the same doses as above could induce significant apoptosis in 48 hours characterized by increased PS translocation and DNA ladder. Sodium selenite at concentration of 2 micromol/L was not able to induce differentiation of NB4 cells, but when combined with 0.1 micromol/L ATRA, CD(11b) expression and NBT reduction were increased as compared with that of 0.1 micromol/L ATRA alone.
  
  
  CONCLUSIONS
  Low dose sodium selenite could enhance the effects of low dose ATRA in inducing apoptosis and differentiation of NB4 cells.
authors.affiliation: Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences and PUMC Hospital, CAMS & PUMC, Beijing 100005, China.
authors.forename: Yimin
authors.initials: Y
authors.lastname: Sun
authors.forename: Lu
authors.initials: L
authors.lastname: Zuo
authors.forename: Caimin
authors.initials: C
authors.lastname: Xu
authors.forename: Ti
authors.initials: T
authors.lastname: Shen
authors.forename: Huazhen
authors.initials: H
authors.lastname: Pan
authors.forename: Zhinan
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D039481:CD11b Antigen / Q000032:analysis; D002454:Cell Differentiation / Q000187:drug effects*; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005434:Flow Cytometry; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute / Q000378:metabolism / Q000473:pathology; D018038:Sodium Selenite / Q000494:pharmacology*; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D039481:CD11b Antigen; D014212:Tretinoin; D018038:Sodium Selenite