SYNOPSIS
Mesenchymal stem cells are important for tissue engineering therapy because they can be seeded in scaffold materials, proliferated and differentiated into osteoblasts. The purpose of this study was to evaluate gene expressions of human mesenchymal stem cells cultured for 14 days in osteogenic differentiation medium that contained ascorbic acid, β-glycerol phosphate and dexamethasone, using 2.9k DNA microarray. It became evident that 198 genes were more than 10-fold up-regulated, but 395 genes were less than 0.1-fold down-regulated with respect to control genes. These 593 genes had wide varieties of biological significance. While ossification-related sialoprotein precursor and osteopontin genes were significantly up-regulated, cartilage-related chondroitin sulfate proteoglycan 2 and aggrecan 1 genes were also up-regulated. Some genes related to angiogenesis, TGF-beta receptor signaling pathway and cell differentiation were also considerably up-regulated. It was concluded that osteogenic differentiation medium differentiated mesenchymal stem cells into not only osteoblasts but also chondroblasts to facili-tate endochondral ossification with vascular invasion in gene expression levels. The list of genes presented here could be used as a database for ossification studies of human mesenchymal stem cells that might be clinically useful.

Key words: Mesenchymal stem cells, DNA-microarray, Osteogenic differentiation medium