title: [Decitabine Enhances the Sensitivity of Leukemia Stem Cell to Allo-NK Cell-Mediated Killing].
abstract: OBJECTIVE
  To investigate the allo-NK cell-mediated killing effect enhanced by decitabine on leukemia stem cells(LSC) and the underlying mechanisms.
  
  
  METHODS
  LSC were separated from KG1a cells by using immunomagnetic beads. Allo-NK cells were isolated and purified from PBMC of healthy donors. Cytotoxicity of allo-NK cells against LSC were measured by LDH releasing assay. The apoptosis induced by allo-NK cells in LSC and the expressions of NKG2D ligands including MICA/B and ULBP1-3 on LSC were detected by flow cytometry.
  
  
  RESULTS
  The killing rate of allo-NK cells to LSC treated with 10 µmol/L decitabine for 24 hours was significant higher than that to LSC without treatment(60.52%±3.52% vs 22.08%±2.07%, 73.93%±2.33% vs 28. 99%±3.13%, 83.08%±1.32% vs 36.44%±2.40%, respectively)at the effector-target ratios of 5:1, 10:1, 20:1 (P<0.05). At the effector-target ratio of 10:1, decitabine significantly enhanced the apoptosis of LSC induced by allo-NK cells (7.84%±0.34% vs 3.33%±0.64%)(P<0.05). The expressions of NKG2D ligands(MICA/B,ULBP1,ULBP2,ULBP3) on LSC treated with decitabine 10 µmol/L for 24 hours were significantly increased (P<0.05).
  
  
  CONCLUSIONS
  Decitabine may enhance the allo-NK cell-mediated killing effects on LSC by up-regulation of the expressions of NKG2D ligands on LSC.
authors.affiliation: Department of Hematology, Guangdong People's Hospital (Guangdong Academy of Medical Sciences), Guangzhou 510080, Guangdong Province, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Hematology, Jingmen Municipal First People's Hospital, Jingmen 448000, Hubei Province, China.
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Wei
authors.affiliation: Department of Nephrology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, Guangdong Province, China.
authors.forename: Jin-Gao
authors.initials: JG
authors.lastname: Li
authors.affiliation: Department of Pathophysiology, Guangdong People Hospital (Guangdong Academy of Medical Sciences), Guangzhou 510080, Guangdong Province, China.
authors.forename: Shao-Xian
authors.initials: SX
authors.lastname: Chen
authors.affiliation: Department of Pathophysiology, Guangdong People Hospital (Guangdong Academy of Medical Sciences), Guangzhou 510080, Guangdong Province, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Hematology, Guangdong People's Hospital (Guangdong Academy of Medical Sciences), Guangzhou 510080, Guangdong Province, China.
authors.forename: Hui-Ting
authors.initials: HT
authors.lastname: Huang
authors.affiliation: Department of Hematology, Guangdong People's Hospital (Guangdong Academy of Medical Sciences), Guangzhou 510080, Guangdong Province, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Peng
authors.affiliation: Department of Hematology, Guangdong People's Hospital (Guangdong Academy of Medical Sciences), Guangzhou 510080, Guangdong Province, China.
authors.forename: Ping-Fang
authors.initials: PF
authors.lastname: Xia
authors.affiliation: Department of Hematology, Guangdong People's Hospital (Guangdong Academy of Medical Sciences), Guangzhou 510080, Guangdong Province, China. E-mail: SMR807@ 163.com.
authors.forename: Miao-Rong
authors.initials: MR
authors.lastname: She
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D001374:Azacitidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D045744:Cell Line, Tumor; D003602:Cytotoxicity, Immunologic; D000077209:Decitabine; D015395:Histocompatibility Antigens Class I; D006801:Humans; D007694:Killer Cells, Natural; D007938:Leukemia / Q000188:drug therapy*; D007963:Leukocytes, Mononuclear; D055655:NK Cell Lectin-Like Receptor Subfamily K; D013234:Stem Cells / Q000187:drug effects*
chemical_list: D000964:Antimetabolites, Antineoplastic; D015395:Histocompatibility Antigens Class I; D055655:NK Cell Lectin-Like Receptor Subfamily K; D000077209:Decitabine; D001374:Azacitidine