title: [The abnormal expression of IKZF1 encoded protein-IKAROS in B-ALL children].
abstract: OBJECTIVE
  To analyze the isoforms of IKAROS in the bone marrow samples from children with acute B-lineage lymphoblastic leukemia (B-ALL) and to investigate the relationship between frequency of dominant-negative (DN) IKAROS isoforms and prognosis of B-ALL, and to preliminarily study the relevant mechanism.
  
  
  METHODS
  A total of 137 children with newly diagnosed B-ALL, who sequentially entered the Department of Hematology and Oncology, Shanghai Children's Medical Center between January 2005 and September 2010, were included in the study. Nest-PCR, Sanger sequencing, and TA cloning were used to analyze the expression of IKAROS isoforms in these children. The relationship between frequency of DN IKAROS isoforms and prognosis of B-ALL was investigated.
  
  
  RESULTS
  Of the 137 children with newly diagnosed B-ALL, 16 had expression of IK6, 14 had expression of IK4, and 2 had expression of IK7. There was significant difference in 2.5-year event-free survival between the cohorts of DN IKAROS and non-DN IKAROS (P=0.01). Analysis of the 10 paired of diagnosis/relapse samples from 10 patients with recurrence showed that 8 of 10 paired diagnosis and relapse samples had inconsistent expression of IKAROS isoforms. The rate of IK6 expression in relapse samples from 21 relapse ALL patients was significantly higher than in the 137 children with newly diagnosed ALL (62% vs 12%, P<0.01).
  
  
  CONCLUSIONS
  Expression of DN IKAROS isoforms can be a poor prognostic factor in B-ALL and is closely associated with recurrence of B-ALL.
authors.affiliation: Hematology and Oncology, Shanghai Children's Medical Center, Shanghai 200127, China. chenjingscmc@hotmail.com.
authors.forename: Xiao-Hang
authors.initials: XH
authors.lastname: Huang
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: Ben-Shang
authors.initials: BS
authors.lastname: Li
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D051740:Ikaros Transcription Factor / Q000235:genetics*; D007223:Infant; D008297:Male; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000378:metabolism* / Q000401:mortality; D011379:Prognosis; D020033:Protein Isoforms / Q000235:genetics
chemical_list: C497239:IKZF1 protein, human; D020033:Protein Isoforms; D051740:Ikaros Transcription Factor