title: High serum microRNA-335 level predicts aggressive tumor progression and unfavorable prognosis in pediatric acute myeloid leukemia.
abstract: OBJECTIVE
  MiRNA expression profiles previously showed the higher expression of microRNA(miR)-335 in bone marrow samples of pediatric acute myeloid leukemia (AML) patients than normal controls. Our aim was to investigate associations of miR-335 expression with tumor progression and prognosis in pediatric AML.
  
  
  METHODS
  Real-time quantitative PCR was performed to detect the expression of miR-335 in bone marrow mononuclear cells and serum obtained from patients with pediatric AML and healthy controls.
  
  
  RESULTS
  Expression levels of miR-335 in the bone marrow and serum of pediatric AML patients were both significantly higher than those in normal controls (both P < 0.001). Then, high serum miR-335 level occurred more frequently in French-American-British classification subtype M7 subtype than in other subtypes (P = 0.03). The expression of serum miR-335 in pediatric AML patients with unfavorable karyotypes was also significantly higher than those in intermediate and favorable groups (P = 0.008). Moreover, high serum miR-335 level was markedly associated with shorter relapse-free and overall survivals (both P < 0.001) of patients with pediatric AML. Furthermore, the multivariate analysis identified the serum miR-335 and cytogenetics risk as independent prognostic factors for both relapse-free and overall survivals. More importantly, the prognostic relevance of serum miR-335 expression was more obvious in the subgroup of patients with intermediate-risk cytogenetics.
  
  
  CONCLUSIONS
  Our data offer the convincing evidence for the first time that serum miR-335 level may be markedly and consistently increased in pediatric AML patients. Serum miR-335 may serve as a promising marker for monitoring the progression and predicting the clinical outcome of patients with this disease.
authors.affiliation: Department of Paediatric Intensive Care Units, Huai'an Maternity and Child Health Hospital of Yangzhou University, Huai'an, 223002, Jiangsu Province, China.
authors.forename: X
authors.initials: X
authors.lastname: Lin
authors.forename: Z
authors.initials: Z
authors.lastname: Wang
authors.forename: R
authors.initials: R
authors.lastname: Zhang
authors.forename: W
authors.initials: W
authors.lastname: Feng
mesh_terms: D000293:Adolescent; D001853:Bone Marrow / Q000473:pathology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D059785:Karyotype; D015470:Leukemia, Myeloid, Acute / Q000097:blood* / Q000145:classification / Q000235:genetics / Q000628:therapy; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008297:Male; D035683:MicroRNAs / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D060888:Real-Time Polymerase Chain Reaction; D015996:Survival Rate; D015854:Up-Regulation
chemical_list: C556347:MIRN335 microRNA, human; D035683:MicroRNAs