Application of Gene Microarrays in the Study of Prostate Cancer
Gene macro- and microarrays have become an increasingly popular tool to investigate gene expression patterns by simultaneously analyzing the expression of thousands of genes in a single experiment. Through careful array design and appropriate analytical tools, one can relate gene expression patterns across large series of data to determine clusters of genes that are co-ordinately regulated as well as correlate patterns to particular disease states or experimental conditions. This approach has been applied to derive relationships between clinical parameters of certain cancers with gene profiles, which potentially may be used as prognostication tools or for identification of therapeutic targets. Although still in its infancy as a clinical laboratory tool, there are several recent reports that illustrate the power of gene microarrays for differential cancer diagnosis. For example, analysis of mRNA from diffuse large B-cell lymphomas using gene microarrays with approx 18,000 cDNA clones revealed two distinct gene expression patterns that were indicative of newly uncovered cancer subtypes and that were predictive of disease survival (1 ). Similarly, there is some preliminary evidence from gene microarray analyses to suggest that gene expression patterns in human breast cancers form two distinctive clusters that correlate with cell proliferation rates and activation of the interferon signal transduction pathway (2 ), although no direct clinical or pathological connections were noted.