title: Long noncoding RNA CCAT1, which could be activated by c-Myc, promotes the progression of gastric carcinoma.
abstract: OBJECTIVE
  Long noncoding RNAs (lncRNAs) have been shown to have functional roles in cancer biology and are deregulated in many tumors. The specific aim of this study was to determine the role of a long noncoding RNA CCAT1 in the progression of gastric carcinoma and discover which factors contribute to the deregulation of CCAT1.
  
  
  METHODS
  A computational screen of CCAT1 promoter was conducted to search for transcription-factor-binding sites. The association of c-Myc with the CCAT1 promoter in vivo was tested by chromatin immunoprecipitation assay. CCAT1 promoter activities were examined by luciferase reporter assay. The function of the c-Myc binding site in the CCAT1 promoter region was tested by a promoter assay with nucleotide substitutions in the putative E-box. The effect of CCAT1 on gastric carcinoma cell proliferation and migration was tested using in vitro cell proliferation and migration assays.
  
  
  RESULTS
  CCAT1 levels were markedly increased in gastric carcinoma tissues compared with normal tissues. c-Myc directly binds to the E-box element in the promoter region of CCAT1, and when ectopically expressed increased promoter activity and expression of CCAT1. Nucleotide substitutions in the E-box element in the promoter region abrogated c-Myc-dependent promoter activation. The expression of CCAT1 and c-Myc shows strong association in gastric carcinomas. Moreover, abnormally expressed CCAT1 promotes cell proliferation and migration.
  
  
  CONCLUSIONS
  These data suggest that c-Myc induction of CCAT1 holds an important role in gastric carcinoma and implicate the potential application of CCAT1 in the treatment of gastric carcinoma.
authors.affiliation: Department of General Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Zhizaoju Road No. 639, Shanghai 200011, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Yang
authors.forename: Xuchao
authors.initials: X
authors.lastname: Xue
authors.forename: Jianwei
authors.initials: J
authors.lastname: Bi
authors.forename: Luming
authors.initials: L
authors.lastname: Zheng
authors.forename: Kangkang
authors.initials: K
authors.lastname: Zhi
authors.forename: Yan
authors.initials: Y
authors.lastname: Gu
authors.forename: Guoen
authors.initials: G
authors.lastname: Fang
mesh_terms: D002277:Carcinoma / Q000235:genetics / Q000473:pathology*; D016022:Case-Control Studies; D018450:Disease Progression; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects / Q000502:physiology; D006801:Humans; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D016271:Proto-Oncogene Proteins c-myc / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D062085:RNA, Long Noncoding / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000502:physiology*; D034741:RNA, Small Interfering / Q000494:pharmacology; D013274:Stomach Neoplasms / Q000235:genetics / Q000473:pathology*; D015533:Transcriptional Activation / Q000235:genetics / Q000502:physiology; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: C579842:CCAT1 long noncoding RNA, human; C489427:MYC protein, human; D016271:Proto-Oncogene Proteins c-myc; D062085:RNA, Long Noncoding; D034741:RNA, Small Interfering