title: Downregulated RhoBTB2 expression contributes to poor outcome in osteosarcoma patients.
abstract: OBJECTIVE
  Osteosarcoma is a malignant bone tumor. RhoBTB2 protein participated in various cellular activities and influenced pathways responsible for cell cycle and apoptosis. To address its potential as a therapeutic target for osteosarcoma, this study investigated the effect of RhoBTB2 expression on osteosarcoma tissue and cell.
  
  
  METHODS
  Real-time PCR and immunohistochemistry analysis were performed to evaluate the level of RhoBTB2 mRNA and protein in 121 osteosarcoma specimens. The relationship of RhoBTB2 expression with clinicopathological parameters of osteosarcoma patients was analyzed using Chi-square test. In addition, a plasmid expressing the RhoBTB2 gene was transfected into human osteosarcoma (HOS) cell using Lipofectamine 2000, and the effects of RhoBTB2 on HOS cell were investigated using 3-(4,5-dimethylthiazolyl)-2,5-diphenyltetrazoliumbromide assay and flow cytometry.
  
  
  RESULTS
  This study reports that RhoBTB2 protein is weakly expressed in osteosarcoma specimens, but highly in normal parts of specimens. RhoBTB2 expression is significantly associated with primary location and local recurrence of osteosarcoma. Overexpression of RhoBTB2 results in significant G1 phase arrest and apoptosis in HOS cell.
  
  
  CONCLUSIONS
  Taken together, we identified the role RhoBTB2 in osteosarcoma tissue and cell. The results might not only be of relevance for diagnosis and prognosis, but potentially also provide a novel target for osteosarcoma therapies.
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of China Medical University , Shenyang, China .
authors.forename: Zhe
authors.initials: Z
authors.lastname: Jin
authors.forename: Ya-Xin
authors.initials: YX
authors.lastname: Han
authors.forename: Xiao-Rui
authors.initials: XR
authors.lastname: Han
mesh_terms: D017209:Apoptosis / Q000502:physiology; D001859:Bone Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D048708:Cell Growth Processes / Q000502:physiology; D045744:Cell Line, Tumor; D015536:Down-Regulation; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D012516:Osteosarcoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D016896:Treatment Outcome; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C497336:RHOBTB2 protein, human; D012333:RNA, Messenger; D025521:Tumor Suppressor Proteins; D019204:GTP-Binding Proteins