title: Identification and functional analysis of differentially expressed genes related to metastatic osteosarcoma.
abstract: BACKGROUND
  To explore the molecular mechanisms of metastatic osteosarcoma (OS) by using the microarray expression profiles of metastatic and non-metastatic OS samples.
  
  
  METHODS
  The gene expression profile GSE37552 was downloaded from Gene Expression Omnibus database, including 2 human metastatic OS cell line models and 2 two non-metastatic OS cell line models. The differentially expressed genes (DEGs) were identified by Multtest package in R language. In addition, functional enrichment analysis of the DEGs was performed by WebGestalt, and the protein-protein interaction (PPI) networks were constructed by Hitpredict, then the signal pathways of the genes involved in the networks were performed by Kyoto Encyclopaedia of Genes and Genomes (KEGG) automatic annotation server (KAAS).
  
  
  RESULTS
  A total of 237 genes were classified as DEGs in metastatic OS. The most significant up- and down-regulated genes were A2M (alpha-2-macroglobulin) and BCAN (brevican). The DEGs were significantly related to the response to hormone stimulus, and the PPI network of A2M contained IL1B (interleukin), LRP1 (low-density lipoprotein receptor-related protein 1) and PDGF (platelet-derived growth factor). Furthermore, the MAPK signaling pathway and focal adhesion were significantly enriched.
  
  
  CONCLUSIONS
  A2M and its interactive proteins, such as IL1B, LRP1 and PDGF may be candidate target molecules to monitor, diagnose and treat metastatic OS. The response to hormone stimulus, MAPK signaling pathway and focal adhesion may play important roles in metastatic OS.
authors.affiliation: Department of Spine Surgery, the First Hospital of Jilin University, Changchun, China E-mail : zs_zshao@163.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Niu
authors.forename: Song
authors.initials: S
authors.lastname: Zhao
authors.forename: Chang-Yan
authors.initials: CY
authors.lastname: Xu
authors.forename: Lin
authors.initials: L
authors.lastname: Chen
authors.forename: Long
authors.initials: L
authors.lastname: Ye
authors.forename: Gui-Bin
authors.initials: GB
authors.lastname: Bi
authors.forename: Gang
authors.initials: G
authors.lastname: Tian
authors.forename: Ping
authors.initials: P
authors.lastname: Gong
authors.forename: Tian-Hong
authors.initials: TH
authors.lastname: Nie
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics*; D001859:Bone Neoplasms / Q000235:genetics* / Q000473:pathology; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D053263:Gene Regulatory Networks; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D012516:Osteosarcoma / Q000235:genetics* / Q000556:secondary; D015398:Signal Transduction; D014407:Tumor Cells, Cultured
chemical_list: D014408:Biomarkers, Tumor