Gene expression profiling was performed on tissue samples via a complementary DNA-mediated annealing, selection, extension, and ligation (DASL) assay (Illumina). 1536 were selected for profiling. 210 prostate cancer samples were used.Random forests classifcation was applied to the DASL data, and a set of genes was selected for further development. Overall design: Total RNA was isolated from prostate cancer prostatecomy samples, purified, cDNA generated, and DASL performed.