title: Egr-1 regulates the transcription of NGX6 gene through a Sp1/Egr-1 overlapping site in the promoter.
abstract: BACKGROUND
  As a novel candidate metastasis suppressor gene, Nasopharyngeal carcinoma-associated gene 6 (NGX6) is involved in cellular growth, cell cycle progression and tumor angiogenesis. Previous studies have shown that NGX6 gene is down-regulated in colorectal cancer (CRC). However, little is known about its transcriptional regulation.
  
  
  RESULTS
  We defined the minimal promoter of NGX6 gene in a 186-bp region (from-86 to +100) through mutation construct methods and luciferase assays. Results from Electrophoretic mobility shift assays (EMSA) and Chromatin immunoprecipitation (ChIP) revealed that Early growth response gene 1 (Egr-1) binds to the Sp1/Egr-1 overlapping site of NGX6 minimal promoter. Overexpression of Egr-1 increased the promoter activity and mRNA level of NGX6 gene; while knock-down of endogenous Egr-1 decreased mRNA expression of NGX6 gene.
  
  
  CONCLUSIONS
  These results demonstrate that Egr-1 regulates NGX6 gene transcription through an overlapping Sp1/Egr-1 binding site as a positive regulator of NGX6 gene.
authors.affiliation: Department of Gastroenterology, Zhuzhou central Hospital, 412007 Zhuzhou, Hunan, China. liuminji1982@163.com.
authors.forename: Minji
authors.initials: M
authors.lastname: Liu
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Wang
authors.forename: Ya
authors.initials: Y
authors.lastname: Peng
authors.forename: Shourong
authors.initials: S
authors.lastname: Shen
authors.forename: Guiyuan
authors.initials: G
authors.lastname: Li
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D045744:Cell Line, Tumor; D003106:Colon / Q000378:metabolism; D003110:Colonic Neoplasms / Q000235:genetics* / Q000378:metabolism; D051766:Early Growth Response Protein 1 / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D016329:Sp1 Transcription Factor / Q000378:metabolism*; D015533:Transcriptional Activation; D025521:Tumor Suppressor Proteins / Q000235:genetics*
chemical_list: D051766:Early Growth Response Protein 1; D008565:Membrane Proteins; D016329:Sp1 Transcription Factor; C477325:TMEM8B protein, human; D025521:Tumor Suppressor Proteins