title: Proteomic analysis of chemonaive pediatric osteosarcomas and corresponding normal bone reveals multiple altered molecular targets.
abstract: With a view to identify the proteins involved in transformation, metastasis or chemoresistance in pediatric osteosarcoma, we carried out a new experimental approach based on comparison of the proteomic profile of paired samples of osteosarcoma and normal bone tissues from the same patient. The proteomic profiles of five pairs of cell lines (normal vs tumoral) were obtained by two-dimensional difference gel electrophoresis. We detected 56 differential protein spots (t test, p < 0.05). Subsequent protein characterization by nano-LC-ESI-MS/MS enabled us to identify some of these proteins, 16 of which were chosen on the basis of the change of their relative abundance between osteosarcomas and paired normal bones and also because their involvement was supported by the genomic analysis. Two of the 16 proteins, Alpha-crystallin B chain (CRYAB) and ezrin (EZR1), were selected for further studies: an immunohistochemical analysis of a TMA (tissue microarray) and real-time PCR for a set of 14 osteosarcoma/normal-bone pairs. The results of this second tier of studies confirmed that there were significant increases in the amounts of CRYAB and ezrin, especially in advanced stages of the disease. Our overall conclusion is that proteomic profiling of paired samples of osteosarcoma and normal bone tissues from the same patient is a practicable and potentially powerful way of initiating and proceeding with a search for proteins and genes involved in pediatric osteosarcoma.
authors.affiliation: Department of Pediatrics, University Clinic of Navarra, Pamplona, Spain.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Folio
authors.forename: María I
authors.initials: MI
authors.lastname: Mora
authors.forename: Marta
authors.initials: M
authors.lastname: Zalacain
authors.forename: Fernando J
authors.initials: FJ
authors.lastname: Corrales
authors.forename: Victor
authors.initials: V
authors.lastname: Segura
authors.forename: Luis
authors.initials: L
authors.lastname: Sierrasesúmaga
authors.forename: Gemma
authors.initials: G
authors.lastname: Toledo
authors.forename: Mikel
authors.initials: M
authors.lastname: San-Julián
authors.forename: Ana
authors.initials: A
authors.lastname: Patiño-García
mesh_terms: D000293:Adolescent; D001859:Bone Neoplasms / Q000737:chemistry / Q000378:metabolism*; D001842:Bone and Bones / Q000737:chemistry / Q000378:metabolism*; D002648:Child; D002853:Chromatography, Liquid; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008297:Male; D009363:Neoplasm Proteins / Q000032:analysis*; D012516:Osteosarcoma / Q000737:chemistry / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D040901:Proteomics / Q000379:methods*; D018709:Statistics, Nonparametric; D053719:Tandem Mass Spectrometry; D046888:Tissue Array Analysis; D014407:Tumor Cells, Cultured; D055815:Young Adult; D038203:alpha-Crystallin B Chain / Q000235:genetics / Q000378:metabolism; D000099149:Ezrin
chemical_list: D003598:Cytoskeletal Proteins; D009363:Neoplasm Proteins; D038203:alpha-Crystallin B Chain; D000099149:Ezrin; C059215:CRYAB protein, human