Identification and Functional Analysis of Differentially Expressed Genes Related to Metastatic Osteosarcoma

Background: To explore the molecular mechanisms of metastatic osteosarcoma (OS) by using the microarrayexpression profiles of metastatic and non-metastatic OS samples. Materials and
Methods: The gene expressionprofile GSE37552 was downloaded from Gene Expression Omnibus database, including 2 human metastaticOS 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 wasperformed 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 Genesand Genomes (KEGG) automatic annotation server (KAAS).
Results: A total of 237 genes were classified asDEGs 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 PPInetwork of A2M contained IL1B (interleukin), LRP1 (low-density lipoprotein receptor-related protein 1) andPDGF (platelet-derived growth factor). Furthermore, the MAPK signaling pathway and focal adhesion weresignificantly enriched.
Conclusions: A2M and its interactive proteins, such as IL1B, LRP1 and PDGF may becandidate 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.