title: [Construction of let-7d expression vector and its inhibitory effect on HMGA2 and ras expression in human ovarian cancer cells in vitro].
abstract: OBJECTIVE
  To elucidate the role of let-7d in regulating the biological behavior of ovarian cancer cells and their expressions of HMGA2 and ras proteins.
  
  
  METHODS
  The pre-let-7d sequence was synthesized and inserted into pcDNA6.2GW/EmGFPmiR and transfected into ovarian cancer IGROV1 cells to cause pre-let-7d overexpression. Real-time quantitative RT-PCR was employed to examine the expression levels of let-7d miRNA and HMGA2 mRNA, and Western blotting was performed to detect the expressions of HMGA2 and ras protein in the transfected cells. The effect of pcDNA6.2GW-let-7d transfection on IGROV1 cell proliferation was determined using MTT assay and the cell apoptosis rate was measured using flow cytometry.
  
  
  RESULTS
  The eukaryotic expression vector containing the target gene let-7d was successfully constructed and transfected into IGROV1 cells. The transfected cells showed a marked reduction of HMGA2 expression but a less obvious down-regulation of ras expression. Transfection with pcDNA6.2GW-let-7d to suppress the expression of HMGA2 caused alterations of the phenotype of IGROV1 cells shown by a reduced proliferative activity and increased cell apoptosis.
  
  
  CONCLUSIONS
  Let-7d plays an important role in altering the malignant cell phenotype of ovarian cancer IGROV1 cells by regulating the expression of HMGA2.
authors.affiliation: Department of Gynecology, Medical Research Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China. yehaiyan5413@139.com
authors.forename: Haiyan
authors.initials: H
authors.lastname: Ye
authors.forename: Jianguo
authors.initials: J
authors.lastname: Chen
authors.forename: Xiaosui
authors.initials: X
authors.lastname: Huang
authors.forename: Ailin
authors.initials: A
authors.lastname: Guo
authors.forename: Peipei
authors.initials: P
authors.lastname: Hao
mesh_terms: D045744:Cell Line, Tumor; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D025743:HMGA2 Protein / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D010051:Ovarian Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D010957:Plasmids; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D025743:HMGA2 Protein; D035683:MicroRNAs; C487931:mirnlet7 microRNA, human; D018631:ras Proteins