title: miR-337 regulates the proliferation and invasion in pancreatic ductal adenocarcinoma by targeting HOXB7.
abstract: BACKGROUND
  miRNAs are involved in coordinating a variety of cellular processes by regulating their target genes. Aberrant expression of miRNAs is correlated with various cancers. Previous studies have shown that miR-337 is significantly down-regulated in pancreatic ductal adenocarcinoma (PDAC) and that its expression is negatively correlated to the expression of HOXB7. Both miR-337 and HOXB7 are associated with the prognosis of PDAC patients. The purpose of this study was to identify the molecular mechanisms by which miR-337 acts as a tumor suppressor in PDAC.
  
  
  METHODS
  Synthetic miR-337 mimics were transfected into PANC-1 and As-PC-1 cells using Lipofectamine™ 2000. The expression of HOXB7 protein was analyzed by Western blot. Luciferase reporter plasmids were constructed to confirm that HOXB7 3'UTR was the target of miR-337. The effect of miR-337 on cell proliferation was evaluated by CCK8 assay and colony formation assay, and cell invasion was evaluated by wound healing assay and transwell assay.
  
  
  RESULTS
  Western blot and luciferase activity assays identified HOXB7 as the target of miR-337. A CCK-8 assay showed the absorbance of cells transfected with miR-337 mimics to be less than that of control cells, and that the number of cell clones was significantly decreased by miR-337 expression. A wound healing assay showed the invasion rate of cells transfected with miR-337 mimics at 36 h to be markedly lower than in controls. The average number of cells penetrating the Matrigel was significantly lower than the controls.
  
  
  CONCLUSIONS
  These findings suggest that miR-337 targets HOXB7 and effects significant suppression of PDAC cell proliferation and invasion.
  The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_171.
authors.affiliation: Department of emergency, the First Affiliated Hospital of Zhengzhou University, No,1 Jianshe Road, Zhengzhou 450052, Henan, China. ruizhang0001@126.com.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.forename: Hong
authors.initials: H
authors.lastname: Leng
authors.forename: Junwen
authors.initials: J
authors.lastname: Huang
authors.forename: Yuwen
authors.initials: Y
authors.lastname: Du
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Wang
authors.forename: Wenqiao
authors.initials: W
authors.lastname: Zang
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Chen
authors.forename: Guoqiang
authors.initials: G
authors.lastname: Zhao
mesh_terms: D021441:Carcinoma, Pancreatic Ductal / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic; D017930:Genes, Reporter; D016147:Genes, Tumor Suppressor; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D009361:Neoplasm Invasiveness; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000473:pathology; D011379:Prognosis; D014162:Transfection
chemical_list: C490538:HOXB7 protein, human; D018398:Homeodomain Proteins; D035683:MicroRNAs; C544075:Mirn337 microRNA, human