title: Identification of differentially expressed microRNAs by microarray: a possible role for microRNAs gene in medulloblastomas.
abstract: BACKGROUND
  MicroRNAs (miRNAs) are small noncoding regulatory RNAs whose aberrant expression may be observed in many malignancies. However, few data are yet available on human primary medulloblastomas. This work aimed to identify that whether miRNAs would be aberrantly expressed in tumor tissues compared with non-tumorous cerebellum tissues from same patients, and to explore a possible role during carcinogenesis.
  
  
  METHODS
  A high throughput microRNA microarray was performed in human primary medulloblastoma specimens to investigate differentially expressed miRNAs, and some miRNAs were validated using real-time quantitative RT-PCR method. In addition, the predicted target genes for the most significantly down- or up-regulated miRNAs were analyzed by using a newly modified ensemble algorithm.
  
  
  RESULTS
  Nine miRNA species were differentially expressed in medulloblastoma specimens versus normal non-tumorous cerebellum tissues. Of these, 4 were over expressed and 5 were under expressed. The changes ranged from 0.02-fold to 6.61-fold. These findings were confirmed using real-time quantitative RT-PCR for most significant deregulated miRNAs (miR-17, miR-100, miR-106b, and miR-218) which are novel and have not been previously published. Interestingly, most of the predicted target genes for these miRNAs were involved in medulloblastoma carcinogenesis.
  
  
  CONCLUSIONS
  MiRNAs are differentially expressed between human medulloblastoma and non-tumorous cerebellum tissue. MiRNAs may play a role in the tumorigenesis of medulloblastoma and maybe serve as potential targets for novel therapeutic strategies in future.
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100050, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Yan-hua
authors.initials: YH
authors.lastname: Gong
authors.forename: Teng-fei
authors.initials: TF
authors.lastname: Chao
authors.forename: Xiao-zhong
authors.initials: XZ
authors.lastname: Peng
authors.forename: Jian-gang
authors.initials: JG
authors.lastname: Yuan
authors.forename: Zhen-yu
authors.initials: ZY
authors.lastname: Ma
authors.forename: Ge
authors.initials: G
authors.lastname: Jia
authors.forename: Ji-zong
authors.initials: JZ
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D008527:Medulloblastoma / Q000235:genetics*; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D035683:MicroRNAs