title: Insights on PRAME and osteosarcoma by means of gene expression profiling.
abstract: BACKGROUND
  Osteosarcoma (OS) is the most frequent bone tumor in children and adolescents. Tumor antigens are encoded by genes that are expressed in many types of solid tumors but are silent in normal tissues, with the exception of placenta and male germ-line cells. It has been proposed that antigen tumors are potential tumor markers.
  
  
  OBJECTIVE
  The premise of this study is that the identification of novel OS-associated transcripts will lead to a better understanding of the events involved in OS pathogenesis and biology.
  
  
  METHODS
  We analyzed the expression of a panel of seven tumor antigens in OS samples to identify possible tumor markers. After selecting the tumor antigen expressed in most samples of the panel, gene expression profiling was used to identify osteosarcoma-associated molecular alterations. A microarray was employed because of its ability to accurately produce comprehensive expression profiles.
  
  
  RESULTS
  PRAME was identified as the tumor antigen expressed in most OS samples; it was detected in 68% of the cases. Microarray results showed differences in expression for genes functioning in cell signaling and adhesion as well as extracellular matrix-related genes, implying that such tumors could indeed differ in regard to distinct patterns of tumorigenesis.
  
  
  CONCLUSIONS
  The hypothesis inferred in this study was gathered mostly from available data concerning other kinds of tumors. There is circumstantial evidence that PRAME expression might be related to distinct patterns of tumorigenesis. Further investigation is needed to validate the differential expression of genes belonging to tumorigenesis-related pathways in PRAME-positive and PRAME-negative tumors.
authors.affiliation: Department of Pediatrics, Pediatric Oncology Institute-GRAACC (Grupo de Apoio ao Adolescente e à Criança com Câncer)/UNIFESP (Federal University of São Paulo), Rua Botucatu no. 743, Floor 8, Genetics Laboratory, Vila Clementino, São Paulo, SP, 04023-062, Brazil. silviatoledo@graacc.org.br
authors.forename: Sílvia Regina Caminada
authors.initials: SR
authors.lastname: Toledo
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Zago
authors.forename: Indhira Dias
authors.initials: ID
authors.lastname: Oliveira
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Proto-Siqueira
authors.forename: Oswaldo K
authors.initials: OK
authors.lastname: Okamoto
authors.forename: Patricia
authors.initials: P
authors.lastname: Severino
authors.forename: Ricardo Z N
authors.initials: RZ
authors.lastname: Vêncio
authors.forename: Francine Tesser
authors.initials: FT
authors.lastname: Gamba
authors.forename: Wilson A
authors.initials: WA
authors.lastname: Silva
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Moreira-Filho
authors.forename: Cristiane A Dalla
authors.initials: CA
authors.lastname: Torre
authors.forename: Maria Tereza Seixas
authors.initials: MT
authors.lastname: Alves
authors.forename: Reynaldo J
authors.initials: RJ
authors.lastname: Garcia-Filho
authors.forename: Andrew J G
authors.initials: AJ
authors.lastname: Simpson
authors.forename: Antonio Sergio
authors.initials: AS
authors.lastname: Petrilli
mesh_terms: D000293:Adolescent; D000328:Adult; D000951:Antigens, Neoplasm / Q000235:genetics*; D001859:Bone Neoplasms / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008297:Male; D012516:Osteosarcoma / Q000235:genetics*; D055815:Young Adult
chemical_list: D000951:Antigens, Neoplasm; C404944:PRAME protein, human