Gene expression profiles of early adipogenesis in human mesenchymal stem cells.

Bone marrow-derived human mesenchymal stem cells (hMSCs) give rise to adipocytes in response to a medium containing dexamethasone, isobutylmethylxanthine, and insulin. A cDNA microarray was applied to analyze the gene expression profiles between the cells at day 0 and at day 3 of incubation in the adipogenic medium, when the cells began to express PPARgamma2, a transcription factor of adipogenesis. Several genes that were regulated during this time period were then confirmed by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Interestingly, several genes identified previously as markers of lineage-specific differentiations other than adipocyte were regulated during adipogenesis. We totally identified 82 genes that were differentially induced by fivefold or greater, and 31 genes that were differentially suppressed by twofold or more. Among them, 55 genes were not previously examined to associate with adipogenesis or have not been determined in hMSCs, therefore, these data provide novel information on the genes involved in adipogenesis of hMSCs.