title: [Role of miR-155 in invasion and metastasis of lung adenocarcinoma A549 cells].
abstract: OBJECTIVE
  To investigate the role and mechanism of miR-155 in invasion and metastasis of lung adenocarcinoma A549 cells.
  
  
  METHODS
  Real-time PCR and fluorescence in situ hybridization were used to detect the miR-155 expression in patients' lung adenocarcinoma and adjacent tissue and lymph nodes. Scratch test and Transwell migration assay were used to assess the effect of miR-155 on the A549 cell migration and invasion capability. Bioinformatics software was used to predict the target genes of miR-155, and using luciferase to assay the target gene. Western blot and real-time PCR were performed to confirm the role of miR-155 expression in the regulation of target gene PTEN.
  
  
  RESULTS
  The real-time quantitative PCR showed that the miR-155 expression levels in adjacent normal tissue, lung adenocarcinoma and metastatic lymph nodes were 4.1±0.5, 9.6±3.1 and 7.8±2.2, respectively. The in situ hybridization showed that the expression rates of miR-155 in the adjacent normal tissue, lung adenocarcinoma and metastatic lymph nodes were (23.2±15.3)%, (75.4±20.2)% and (60.4±25.1)%, respectively. The Scratch assay showed that the wound healing rates in the miR-155 mimics group, miR-155 mimics NC group, miR-155 inhibitor group and miR-155 inhibitor NC group at 24 h were (43.2±2.2)%, (21.3±4.2)%, (24.3±5.3)%, and (35.2±5.1)%, and that at 48 h were (75.2±4.5)%, (52.6±5.2)%, (39.4±4.2)%, and (51.5±4.3)%, respectively. Dual luciferase reporter gene assay showed that the value of the luciferase in the miR-155 mimics group co-transfected with PTEN 3'UTR-containing wild-type and mutant plasmids were 4.7±0.5 and 7.3±0.7, and the miR-155 mimics luciferase values of the control group co-transfected with PTEN 3'UTR-containing wild-type and mutant plasmids were 7.8±0.9 and 7.5±0.8, respectively. The real-time quantitative fluorescence PCR showed that the relative expression of PTEN protein in the miR-155 mimics group, miR-155 mimics control group, miR-155 mimics inhibitor group, and miR-155 inhibitor control group were 0.5±0.3, 1.0±0.1, 2.2±0.2 and 1.2±0.1, respectively. The Western blot assay detected that the relative expression of PTEN protein levels in the miR-155 mimics group, miR-155 mimics control group, miR-155 inhibitor group and miR-155 inhibitor control group were 0.4±0.1, 1.0±0.3, 2.8±0.2 and 1.4±0.1, respectively. The differences in PTEN mRNA and protein expressions of the four groups were statistically significant (P<0.05 for all).
  
  
  CONCLUSIONS
  miR-155 may promote the invasion and metastasis of lung adenocarcinoma through reducing the target PTEN gene expression.
authors.affiliation: Department of Respiratory Medicine, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: T L
authors.initials: TL
authors.lastname: Cheng
authors.forename: C P
authors.initials: CP
authors.lastname: Hu
authors.forename: M
authors.initials: M
authors.lastname: Li
authors.forename: Q H
authors.initials: QH
authors.lastname: Gu
authors.forename: J
authors.initials: J
authors.lastname: An
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology* / Q000556:secondary*; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D015870:Gene Expression; D017930:Genes, Reporter; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008156:Luciferases; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D035683:MicroRNAs / Q000378:metabolism / Q000502:physiology*; D009361:Neoplasm Invasiveness; D051059:PTEN Phosphohydrolase / Q000235:genetics* / Q000378:metabolism; D010957:Plasmids; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D014162:Transfection
chemical_list: C524942:MIRN155 microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; D008156:Luciferases; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human