title: MYCT1-TV, a novel MYCT1 transcript, is regulated by c-Myc and may participate in laryngeal carcinogenesis.
abstract: BACKGROUND
  MYCT1, a putative target of c-Myc, is a novel candidate tumor suppressor gene cloned from laryngeal squamous cell carcinoma (LSCC). Its transcriptional regulation and biological effects on LSCC have not been clarified.
  
  
  RESULTS
  Using RACE assay, we cloned a 1106 bp transcript named Myc target 1 transcript variant 1 (MYCT1-TV) and confirmed its transcriptional start site was located at 140 bp upstream of the ATG start codon of MYCT1-TV. Luciferase, electrophoretic mobility shift and chromatin immunoprecipitation assays confirmed c-Myc could regulate the promoter activity of MYCT1-TV by specifically binding to the E-box elements within -886 to -655 bp region. These results were further verified by site-directed mutagenesis and RNA interference (RNAi) assays. MYCT1-TV and MYCT1 expressed lower in LSCC than those in paired adjacent normal laryngeal tissues, and overexpression of MYCT1-TV and MYCT1 could inhibit cell proliferation and invasion and promote apoptosis in LSCC cells.
  
  
  CONCLUSIONS
  Our data indicate that MYCT1-TV, a novel MYCT1 transcript, is regulated by c-Myc and down-regulation of MYCT1-TV/MYCT1 could contribute to LSCC development and function.
authors: Department of Medical Genetics, China Medical University, Shenyang, People's Republic of China.
authors: Shuang
authors: S
authors: Fu
authors: Yan
authors: Y
authors: Guo
authors: Hong
authors: H
authors: Chen
authors: Zhen-Ming
authors: ZM
authors: Xu
authors: Guang-Bin
authors: GB
authors: Qiu
authors: Ming
authors: M
authors: Zhong
authors: Kai-Lai
authors: KL
authors: Sun
authors: Wei-Neng
authors: WN
authors: Fu
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D024721:E-Box Elements / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D020868:Gene Silencing; D014644:Genetic Variation; D057809:HEK293 Cells; D006801:Humans; D007822:Laryngeal Neoplasms / Q000235:genetics / Q000473:pathology*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D016271:Proto-Oncogene Proteins c-myc / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D024363:Transcription Initiation Site
chemical_list: C477074:MYCT1 protein, human; D009687:Nuclear Proteins; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger