title: Upregulation of microRNA-21 is a poor prognostic marker in patients with childhood B cell acute lymphoblastic leukemia.
abstract: OBJECTIVE
  Many studies have demonstrated that microRNA-21 (miR-21) is an oncogene and is upregulated in tumor tissue. However, its association with B-cell acute lymphoblastic leukemia (B-ALL) remains poorly understood.
  
  
  METHODS
  The expression of miR-21 was detected by real-time quantitative PCR in 75 children with de novo B-ALL as well as in 50 healthy controls. This study was conducted to evaluate the miR-21 as a biomarker for risk assessment, diagnosis and prognosis.
  
  
  CONCLUSIONS
  Compared with normal controls, miR-21 expression was significantly upregulated in childhood B-ALL patients. Using the receiver operating characteristic curve 3.23 was selected as the cut-off value of miR-21 expression in distinguishing patients from controls. Patients group with High miR-21 expression was significantly associated with those aged <2 and >10 years, lower platelets count, more incidence of CNS infiltration and poorer treatment outcome also, they showed a significantly poorer disease-free survival (DFS) and overall survival (OS) compared to those with low miR-21 expression group. Its expression was an independent prognostic marker according to multivariate analysis.
  
  
  CONCLUSIONS
  This is the first report demonstrating the upregulation of miR-21 in childhood B-ALL, and its association with poor response to induction therapy, shorter DFS and OS. These results suggest that miR-21 upregulation represent an unfavorable prognostic marker in Childhood B-ALL.
authors.affiliation: a Clinical Pathology Department, Faculty of Medicine , Zagazig University , Zagazig , Egypt.
authors.forename: Hany Abedelmalik
authors.initials: HA
authors.lastname: Labib
authors.affiliation: b Internal Medicine Department, Faculty of Medicine , Zagazig University , Zagazig , Egypt.
authors.forename: Neveen G
authors.initials: NG
authors.lastname: Elantouny
authors.affiliation: b Internal Medicine Department, Faculty of Medicine , Zagazig University , Zagazig , Egypt.
authors.forename: Nevin F
authors.initials: NF
authors.lastname: Ibrahim
authors.affiliation: c Medical Oncology Department, Faculty of Medicine , Zagazig University , Zagazig , Egypt.
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: Alnagar
mesh_terms: D000367:Age Factors; D014408:Biomarkers, Tumor; D016022:Case-Control Studies; D002648:Child; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis / Q000235:genetics* / Q000401:mortality* / Q000628:therapy; D011379:Prognosis; D016016:Proportional Hazards Models; D012372:ROC Curve; D016896:Treatment Outcome; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor; C524940:MIRN21 microRNA, human; D035683:MicroRNAs
keywords: B-ALL; Childhood; miR-21