title: MicroRNA-21 is overexpressed in human cholangiocarcinoma and regulates programmed cell death 4 and tissue inhibitor of metalloproteinase 3.
abstract: Cholangiocarcinomas (CCAs) are aggressive cancers, with high mortality and poor survival rates. Only radical surgery offers patients some hope of cure; however, most patients are not surgical candidates because of late diagnosis secondary to relatively poor accuracy of diagnostic means. MicroRNAs (miRs) are involved in every cancer examined, but they have not been evaluated in primary CCA. In this study, miR arrays were performed on five primary CCAs and five normal bile duct specimens (NBDs). Several miRs were dysregulated and miR-21 was overexpressed in CCAs. miR-21 differential expression in these 10 specimens was verified by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). To validate these findings, qRT-PCR for miR-21 was then performed on 18 additional primary CCAs and 12 normal liver specimens. MiR-21 was 95% sensitive and 100% specific in distinguishing between CCA and normal tissues, with an area under the receiver operating characteristic curve of 0.995. Inhibitors of miR-21 increased protein levels of programmed cell death 4 (PDCD4) and tissue inhibitor of metalloproteinases 3 (TIMP3). Notably, messenger RNA levels of TIMP3 were significantly lower in CCAs than in normals.
  
  
  CONCLUSIONS
  MiR-21 is overexpressed in human CCAs. Furthermore, miR-21 may be oncogenic, at least in part, by inhibiting PDCD4 and TIMP3. Finally, these data suggest that TIMP3 is a candidate tumor suppressor gene in the biliary tree.
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA. fselaru1@jhmi.edu
authors.forename: Florin M
authors.initials: FM
authors.lastname: Selaru
authors.forename: Alexandru V
authors.initials: AV
authors.lastname: Olaru
authors.forename: Takatsugu
authors.initials: T
authors.lastname: Kan
authors.forename: Stefan
authors.initials: S
authors.lastname: David
authors.forename: Yulan
authors.initials: Y
authors.lastname: Cheng
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Mori
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
authors.forename: Bogdan
authors.initials: B
authors.lastname: Paun
authors.forename: Zhe
authors.initials: Z
authors.lastname: Jin
authors.forename: Rachana
authors.initials: R
authors.lastname: Agarwal
authors.forename: James P
authors.initials: JP
authors.lastname: Hamilton
authors.forename: John
authors.initials: J
authors.lastname: Abraham
authors.forename: Christos
authors.initials: C
authors.lastname: Georgiades
authors.forename: Hector
authors.initials: H
authors.lastname: Alvarez
authors.forename: Perumal
authors.initials: P
authors.lastname: Vivekanandan
authors.forename: Wayne
authors.initials: W
authors.lastname: Yu
authors.forename: Anirban
authors.initials: A
authors.lastname: Maitra
authors.forename: Michael
authors.initials: M
authors.lastname: Torbenson
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Thuluvath
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Gores
authors.forename: Nicholas F
authors.initials: NF
authors.lastname: LaRusso
authors.forename: Ralph
authors.initials: R
authors.lastname: Hruban
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Meltzer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D001650:Bile Duct Neoplasms / Q000378:metabolism*; D001653:Bile Ducts, Intrahepatic / Q000378:metabolism*; D045744:Cell Line, Tumor; D018281:Cholangiocarcinoma / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000378:metabolism*; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000378:metabolism*
chemical_list: D051017:Apoptosis Regulatory Proteins; C524940:MIRN21 microRNA, human; D035683:MicroRNAs; C114487:PDCD4 protein, human; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C088390:TIMP3 protein, human; D019717:Tissue Inhibitor of Metalloproteinase-3