Gene-expression profiling of human osteoblasts following treatment with the ionic products of Bioglass (R) 45S5 dissolution

The effect of the ionic products of Bioglass(R) 45S5 dissolution on the gen e-expression profile of human osteoblasts was investigated by cDNA microarr ay analysis of 1,176 genes. Treatment with the ionic products of Bioglass(R ) 45S5 dissolution increased the levels of 60 transcripts twofold or more a nd reduced the levels of five transcripts to one-half or less than in contr ol. Markedly up-regulated genes included RCL, a c-myc responsive growth rel ated gene, cell cycle regulators such as G1/S specific cyclin D1, and apopt osis regulators including calpain and defender against cell death (DAD1). O ther significantly up-regulated genes included the cell surface receptors C D44 and integrin beta1, and various extracellular matrix regulators includi ng metalloproteinases-2 and -4 and their inhibitors TIMP-1 and TIMP-2. The identification of differentially expressed genes by cDNA microarray analysi s has offered new insights into the mode of action of bioactive glasses and has proven to be an effective tool in evaluating their osteoproductive pro perties. (C) 2001 John Wiley & Sons, Inc.