Novel findings in gene expression detected in human osteosarcoma by cDNA microarray

cDNA microarray analysis was used to screen for gene expression alterations in human osteosarcoma cell lines. The analysis using three cell lines reve aled changes in the expression of several genes in comparison with normal h uman osteoblasts. Among the 5,184 sequences that were analyzed, 35 showed a berrant expression in all the cell lines. Eight of these showed overexpress ion and 27 underexpression compared to their expression levels in osteoblas ts. The most highly upregulated genes included heat shock protein 90 beta a nd polyadenylate-binding protein-like 1. Commonly down-regulated genes incl uded fibronectin 1 and thrombospondin 1. RT-PCR was used to verify these ch anges in the cell lines and in three primary osteosarcoma samples. This stu dy shows that (1) gene expression pattern in osteosarcoma cell lines differ s considerably from normal osteo; blasts, (2) osteosarcoma cell lines can b e used as a model system to detect novel gene expression alterations presen t in primary tumors, (3) the overexpression of heat shock protein 90 beta a nd poly adenylate-binding protein-like 1, and (4) the down-regulation of fi bronectin 1 and thrombospondin 1 may play a role in the development and/or progression of osteosarcoma. This study indicates that microarray-based exp ression surveys may be used to establish the molecular fingerprint of osteo sarcoma, however, larger cDNA chips and more tumor specimens are required t o define the clinically relevant gene expression patterns. (C) 2000 Elsevie r Science Inc. All rights reserved.