title: Meta-analysis of differentially expressed genes in osteosarcoma based on gene expression data.
abstract: BACKGROUND
  To uncover the genes involved in the development of osteosarcoma (OS), we performed a meta-analysis of OS microarray data to identify differentially expressed genes (DEGs) and biological functions associated with gene expression changes between OS and normal control (NC) tissues.
  
  
  METHODS
  We used publicly available GEO datasets of OS to perform a meta-analysis. We performed Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and Protein-Protein interaction (PPI) networks analysis.
  
  
  RESULTS
  Eight GEO datasets, including 240 samples of OS and 35 samples of controls, were available for the meta-analysis. We identified 979 DEGs across the studies between OS and NC tissues (472 up-regulated and 507 down-regulated). We found GO terms for molecular functions significantly enriched in protein binding (GO: 0005515, P = 3.83E-60) and calcium ion binding (GO: 0005509, P = 3.79E-13), while for biological processes, the enriched GO terms were cell adhesion (GO:0007155, P = 2.26E-19) and negative regulation of apoptotic process (GO: 0043066, P = 3.24E-15), and for cellular component, the enriched GO terms were cytoplasm (GO: 0005737, P = 9.18E-63) and extracellular region (GO: 0005576, P = 2.28E-47). The most significant pathway in our KEGG analysis was Focal adhesion (P = 5.70E-15). Furthermore, ECM-receptor interaction (P = 1.27E-13) and Cell cycle (P = 4.53E-11) are found to be highly enriched. PPI network analysis indicated that the significant hub proteins containing PTBP2 (Degree = 33), RGS4 (Degree = 15) and FXYD6 (Degree = 13).
  
  
  CONCLUSIONS
  Our meta-analysis detected DEGs and biological functions associated with gene expression changes between OS and NC tissues, guiding further identification and treatment for OS.
authors.affiliation: Bone and Soft Tissue Tumors Research Center of Yunnan Province, Department of Orthopaedics, The Third Affiliated Hospital of Kunming Medical University (Tumor Hospital of Yunnan Province), Kunming, Yunnan 650118, PR China. yangzuozhangpre@163.com.
authors.forename: Zuozhang
authors.initials: Z
authors.lastname: Yang
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Chen
authors.forename: Yu
authors.initials: Y
authors.lastname: Fu
authors.forename: Yihao
authors.initials: Y
authors.lastname: Yang
authors.forename: Ya
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yanjin
authors.initials: Y
authors.lastname: Chen
authors.forename: Dongqi
authors.initials: D
authors.lastname: Li
mesh_terms: D002135:Calcium-Binding Proteins / Q000235:genetics; D002453:Cell Cycle / Q000235:genetics; D030541:Databases, Genetic; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D063990:Gene Ontology; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D012516:Osteosarcoma / Q000235:genetics*; D011485:Protein Binding / Q000235:genetics; D060066:Protein Interaction Maps / Q000235:genetics*
chemical_list: D002135:Calcium-Binding Proteins