title: Expression of NLRR3 orphan receptor gene is negatively regulated by MYCN and Miz-1, and its downregulation is associated with unfavorable outcome in neuroblastoma.
abstract: OBJECTIVE
  Our previous study showed that expression of NLRR3 is significantly high in favorable neuroblastomas (NBL), whereas that of NLRR1 is significantly high in unfavorable NBLs. However, the molecular mechanism of transcriptional regulation of NLRR3 remains elusive. This study was undertaken to clarify the transcriptional regulation of NLRR3 and its association with the prognosis of NBL.
  
  
  METHODS
  NLRR3 and MYCN expressions in NBL cell lines were analyzed after induction of cell differentiation, MYCN knockdown, and overexpression. The transcriptional regulation of NLRR3 was analyzed by luciferase reporter and chromatin immunoprecipitation assays. Quantitative PCR was used for examining the expression of NLRR3, Miz-1, or MYCN in 87 primary NBLs.
  
  
  RESULTS
  The expression of NLRR3 mRNA was upregulated during differentiation of NBL cells induced by retinoic acid, accompanied with reduced expression of MYCN, suggesting that NLRR3 expression was inversely correlated with MYCN in differentiation. Indeed, knockdown of MYCN induced NLRR3 expression, whereas exogenously expressed MYCN reduced cellular NLRR3 expression. We found that Miz-1 was highly expressed in favorable NBLs and NLRR3 was induced by Miz-1 expression in NBL cells. MYCN and Miz-1 complexes bound to NLRR3 promoter and showed a negative regulation of NLRR3 expression. In addition, a combination of low expression of NLRR3 and high expression of MYCN was highly associated with poor prognosis.
  
  
  CONCLUSIONS
  NLRR3 is a direct target of MYCN, which associates with Miz-1 and negatively regulates NLRR3 expression. NLRR3 may play a role in NBL differentiation and the survival of NBL patients by inversely correlating with MYCN amplification.
authors: Division of Biochemistry and Innovative Cancer Therapeutics, Chiba Cancer Center, Chiba, Japan.
authors: Jesmin
authors: J
authors: Akter
authors: Atsushi
authors: A
authors: Takatori
authors: Md Shamim
authors: MS
authors: Hossain
authors: Toshinori
authors: T
authors: Ozaki
authors: Atsuko
authors: A
authors: Nakazawa
authors: Miki
authors: M
authors: Ohira
authors: Yusuke
authors: Y
authors: Suenaga
authors: Akira
authors: A
authors: Nakagawara
mesh_terms: D002454:Cell Differentiation / Q000235:genetics; D045744:Cell Line, Tumor; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006801:Humans; D051741:Kruppel-Like Transcription Factors / Q000096:biosynthesis / Q000235:genetics*; D008562:Membrane Glycoproteins; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics*; D000071447:N-Myc Proto-Oncogene Protein; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics*; D009447:Neuroblastoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D009474:Neurons / Q000473:pathology; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000235:genetics*; D015513:Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics*; D011379:Prognosis; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000235:genetics; D014162:Transfection
chemical_list: D051741:Kruppel-Like Transcription Factors; C494422:LRRN3 protein, human; C459801:MYCN protein, human; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D000071447:N-Myc Proto-Oncogene Protein; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D015513:Oncogene Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C107961:ZBTB17 protein, human