Expression profiling in cancer using cDNA microarrays

Currently there are over 1 000 000 human expressed sequence tag (EST) seque nces available on the public database, representing perhaps 50-90% of all h uman genes. The cDNA microarray technique is a recently developed tool that exploits this wealth of information for the analysis of gene expression. I n this method, DNA probes representing cDNA clones are arrayed onto a glass slide and interrogated with fluorescently labeled cDNA targets. The power: of the technology is the ability to perform a genome-wide expression profi le of thousands of genes in one experiment. In our review we describe the p rinciples of the microarray technology as applied to cancer research, summa rize the literature on its use so far, and speculate on the future applicat ion of this powerful technique.