title: Mir-655 up-regulation suppresses cell invasion by targeting pituitary tumor-transforming gene-1 in esophageal squamous cell carcinoma.
abstract: BACKGROUND
  MicroRNAs (miRNAs) can act as either oncogenes or tumor suppressor genes under different conditions and thus can play a significant role in cancer development. We investigated miR-655 expression in a cohort of esophageal squamous cell carcinoma (ESCC) to assess the impact of this miRNA on ESCC cell invasion and metastasis.
  
  
  METHODS
  A qRT-PCR assay was used to quantify miR-655 expression levels in 34 paired ESCC samples and adjacent non-tumor tissues. Wound healing and transwell assays were used to evaluate the effects of miR-655 expression on the invasiveness of ESCC cells. Luciferase reporter and western blot assays were used to determine whether the mRNA encoding pituitary tumor-transforming gene-1 (PTTG1) is a major target of miR-655.
  
  
  RESULTS
  The expression level of miR-655 in ESCC tissues was found to be lower than in adjacent non-tumor tissues (P < 0.05). This relatively low expression level was significantly associated with the occurrence of lymph node metastases (P < 0.05). Migration rates were significantly lower for two ESCC-derived cell lines (EC9706 and KYSE150) transfected with miR-429 mimics (P < 0.05). Subsequent western blot and luciferase reporter assays demonstrated that miR-655 could bind to putative binding sites within the PTTG1 mRNA 3'-untranslated region (3'-UTR) and thus reduce the expression.
  
  
  CONCLUSIONS
  miR-655 is expressed at low levels in primary ESCC tissues, and up-regulation of miR-655 inhibits ESCC cell invasiveness by targeting PTTG1. Our findings suggest that PTTG1 may act as a major target of miR-655. This study improves our understanding of the mechanisms underlying ESCC pathogenesis and may promote the development of novel targeted therapies.
authors: Yuanyuan
authors: Y
authors: Wang
authors: Wenqiao
authors: W
authors: Zang
authors: Yuwen
authors: Y
authors: Du
authors: Yunyun
authors: Y
authors: Ma
authors: Min
authors: M
authors: Li
authors: Ping
authors: P
authors: Li
authors: Xudong
authors: X
authors: Chen
authors: Tao
authors: T
authors: Wang
authors: Ziming
authors: Z
authors: Dong
authors: College of Basic Medical Sciences, Zhengzhou University, No,100 Kexue Road, Zhengzhou, Henan 450001, China. zhaogq@zzu.edu.cn.
authors: Guoqiang
authors: G
authors: Zhao
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000473:pathology*; D045744:Cell Line, Tumor; D015536:Down-Regulation; D004797:Enzyme-Linked Immunosorbent Assay; D004938:Esophageal Neoplasms / Q000235:genetics / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D060888:Real-Time Polymerase Chain Reaction; D064249:Securin / Q000235:genetics*; D015854:Up-Regulation
chemical_list: C585264:MIRN655 microRNA, human; D035683:MicroRNAs; D064249:Securin; C578002:pituitary tumor-transforming protein 1, human