title: Biological Activities of RUNX1 Mutants Predict Secondary Acute Leukemia Transformation from Chronic Myelomonocytic Leukemia and Myelodysplastic Syndromes.
abstract: OBJECTIVE
  Transcription factor RUNX1 is essential for normal hematopoiesis. High mutation frequencies of RUNX1 gene in chronic myelomonocytic leukemia (CMML) and myelodysplastic syndromes (MDS) have been described, whereas the biologic significances of the mutations were not investigated. Here, we aimed to correlate the biologic activities of the RUNX1 mutants with the clinical outcomes of patients.
  
  
  METHODS
  We examined the mutational status of RUNX1 in 143 MDS and 84 CMML patients. Then, we studied the DNA and CBFβ binding abilities of all the RUNX1 mutants identified by using electrophoretic mobility shift assay and co-immunoprecipitation assay, and also determined their activities on target C-FMS gene induction by Western blotting and luciferase reporter assay. Using luciferase reporter assay, the relative biologic activities of each RUNX1 mutant could be quantified and correlated with the patient outcomes by statistical analyses.
  
  
  RESULTS
  We observed that most RUNX1 mutants had reduced abilities in DNA binding, CBFβ heterodimerization, and C-FMS gene induction. The relative biologic activities of RUNX1 mutants were grouped into high- and low-activity mutations. Correlation of the activities of RUNX1 mutants with the clinical outcomes revealed that patients harboring lower activities of RUNX1 mutants had a higher risk and shorter time to secondary acute myeloid leukemia transformation in MDS and CMML. In multivariate analysis, low RUNX1 activity remained an independent predictor for secondary acute myeloid leukemia-free survival in MDS patients.
  
  
  CONCLUSIONS
  The biologic activity rather than the mutational status of RUNX1 might be an indicator in predicting outcome of patients with MDS and CMML.
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Shu-Chun
authors.initials: SC
authors.lastname: Tsai
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan. College of Medicine, Chang Gung University, Taoyuan, Taiwan. sly7012@adm.cgmh.org.tw.
authors.forename: Lee-Yung
authors.initials: LY
authors.lastname: Shih
authors.affiliation: Division of Pediatric Hematology-Oncology, Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan.
authors.forename: Sung-Tzu
authors.initials: ST
authors.lastname: Liang
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Ying-Jung
authors.initials: YJ
authors.lastname: Huang
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan. College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Ming-Chung
authors.initials: MC
authors.lastname: Kuo
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Chein-Fuang
authors.initials: CF
authors.lastname: Huang
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Yu-Shu
authors.initials: YS
authors.lastname: Shih
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Tung-Huei
authors.initials: TH
authors.lastname: Lin
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Ming-Chun
authors.initials: MC
authors.lastname: Chiu
authors.affiliation: Division of Pediatric Hematology-Oncology, Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan.
authors.forename: Der-Cherng
authors.initials: DC
authors.lastname: Liang
mesh_terms: D002471:Cell Transformation, Neoplastic / Q000235:genetics* / Q000473:pathology; D050676:Core Binding Factor Alpha 2 Subunit / Q000235:genetics*; D050658:Core Binding Factor beta Subunit / Q000235:genetics / Q000378:metabolism; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D015973:Gene Expression Regulation, Leukemic / Q000235:genetics; D057809:HEK293 Cells; D006801:Humans; D015477:Leukemia, Myelomonocytic, Chronic / Q000235:genetics* / Q000473:pathology; D008297:Male; D009154:Mutation; D009190:Myelodysplastic Syndromes / Q000235:genetics* / Q000473:pathology; D009363:Neoplasm Proteins / Q000096:biosynthesis; D011379:Prognosis; D016186:Receptor, Macrophage Colony-Stimulating Factor / Q000235:genetics
chemical_list: C493692:CBFB protein, human; D050676:Core Binding Factor Alpha 2 Subunit; D050658:Core Binding Factor beta Subunit; D004268:DNA-Binding Proteins; D009363:Neoplasm Proteins; C493728:RUNX1 protein, human; D016186:Receptor, Macrophage Colony-Stimulating Factor