title: MiR-455-5p acts as a novel tumor suppressor in gastric cancer by down-regulating RAB18.
abstract: OBJECTIVE
  To detect the potential regulation pathway of microRNA-455-5p (miR-455-5p) and RAB18, member RAS oncogene family (RAB18) in gastric cancer (GC) cells and tissues and discuss the clinical significance of miR-455-5p in GC genesis and progression.
  
  
  METHODS
  Real-time PCR was used to measure mRNA level of miR-455-5p in GC, TargetScan and dual luciferase assay were used to predict and demonstrate the candidate target gene of miR-455-5p, Western blot were utilized to detect the protein level of RAB18. Cell function assays were also performed to determine the function of miR-455-5p in GC.
  
  
  RESULTS
  miR-455-5p was reduced significantly in gastric cancer cells and tissues compared with the corresponding normal control, the lower expression of miR-455-5p was related to advanced clinical stage in gastric cancer, re-expression of miR-455-5p could inhibit human GC cell proliferation and invasion, overexpression of miR-455-5p could also promote GC cell apoptosis. Furthermore, we found that RAB18 was a candidate target of miR-455-5p. Re-expression of miR-455-5p could inhibit the protein level of RAB18.
  
  
  CONCLUSIONS
  MiR-455-5p might serve as a novel biomarker in gastric cancer by targeting RAB18.
authors.affiliation: Department of Gastroenterological Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.
authors.forename: Jichao
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Gastroenterological Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.
authors.forename: Jiakui
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Gastroenterological Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.
authors.forename: Yongshuang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Gastroenterological Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Gastroenterological Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.
authors.forename: Baiqiang
authors.initials: B
authors.lastname: Sui
authors.affiliation: Department of Gastroenterological Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, China. Electronic address: daidq2016@163.com.
authors.forename: Dongqiu
authors.initials: D
authors.lastname: Dai
mesh_terms: D017209:Apoptosis; D014408:Biomarkers, Tumor / Q000235:genetics*; D045744:Cell Line, Tumor; D002465:Cell Movement; D015536:Down-Regulation; D005260:Female; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; C583404:MIRN455 microRNA, human; D035683:MicroRNAs; C484168:RAB18 protein, human; D020691:rab GTP-Binding Proteins
keywords: Gastric cancer; MiR-455-5p; RAB18; Tumor suppressor