title: MicroRNA-338-3p inhibits colorectal carcinoma cell invasion and migration by targeting smoothened.
abstract: OBJECTIVE
  To investigate the regulative effect of microRNA-338-3p on colorectal carcinoma cell invasion and migration.
  
  
  METHODS
  The microRNA-338-3p expression pattern of colorectal carcinoma tissues and cell lines was detected by real-time reverse transcriptase polymerase chain reaction. The protein level of smoothened was detected by western blot analysis. Furthermore, colorectal carcinoma cells were pretreated with or without anti-smoothened-small interfering ribonucleic acid prior to the addition of pre-microRNA-338-3p or anti-microRNA-338-3p. The status of colorectal carcinoma cell invasion and that of migration were detected by transwell assay and wound healing assay, respectively.
  
  
  RESULTS
  The expression of microRNA-338-3p was significantly down-regulated in colorectal carcinoma tissues in comparison with those in the adjacent non-tumorous tissues, and the value was negatively related to advanced tumor, node, metastasis stage and local invasion. The expression of microRNA-338-3p in colorectal carcinoma cells transfected with pre-microRNA-338-3p p was significantly increased. Furthermore, over-expression of microRNA-338-3p inhibited the expression of smoothened protein in colorectal carcinoma cells, which showed obviously suppressed invasion and migration ability. The expression of microRNA-338-3p in colorectal carcinoma cells transfected with anti-microRNA-338-3p was significantly decreased. Moreover, the down-regulated expression of microRNA-338-3p caused the up-regulated expression of smoothened protein in colorectal carcinoma cells, which showed significantly enhanced invasion and migration ability. However, anti-smoothened-small interfering ribonucleic acid largely, but not completely, reversed the effects induced by blockage of microRNA-338-3p, suggesting that the regulative effect of microRNA-338-3p on colorectal carcinoma cell invasion and migration was indeed mediated by smoothened. Additionally, smoothened was identified as a direct target of microRNA-338-3p by luciferase assay.
  
  
  CONCLUSIONS
  MicroRNA-338-3p could inhibit colorectal carcinoma cell invasion and migration by inhibiting smoothened expression.
authors.affiliation: *Department of General Surgery, Nanfang Hospital of Southern Medical University, Guangzhou 510515, Guangdong Province, China. sunkai9602@sina.com.
authors.forename: Qi
authors.initials: Q
authors.lastname: Xue
authors.forename: Kai
authors.initials: K
authors.lastname: Sun
authors.forename: Hai-Jun
authors.initials: HJ
authors.lastname: Deng
authors.forename: Shang-Tong
authors.initials: ST
authors.lastname: Lei
authors.forename: Jing-Qing
authors.initials: JQ
authors.lastname: Dong
authors.forename: Guo-Xin
authors.initials: GX
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D015153:Blotting, Western; D002465:Cell Movement / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D015536:Down-Regulation; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D060888:Real-Time Polymerase Chain Reaction; D043562:Receptors, G-Protein-Coupled / Q000187:drug effects / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000072086:Smoothened Receptor; D014162:Transfection; D015854:Up-Regulation
chemical_list: C532050:MIRN338 microRNA, human; D035683:MicroRNAs; D043562:Receptors, G-Protein-Coupled; C491023:SMO protein, human; D000072086:Smoothened Receptor
keywords: Hsa-miR-338-3p; colorectal carcinoma; invasion; migration; smoothened