Transcriptome profiling is a powerful method for monitoring genes and their expression levels under a variety of conditions. Completion of the human genome and advances in high-throughput gene microarray instrumentation enables one to collect large amounts of data in a relatively short time. The challenge then becomes that of data analysis to identify patterns in expression changes and, from there, to relate the observed changes to functional compartments and pathways in cells, tissues, and organisms. Using cultured human ovarian cancer cells as an experimental model cellular system, we describe approaches that are used in analysis of the transcriptome, focusing on those genes encoding proteins and microRNAs. Coupled with other approaches described herein, one can also use the transcriptome to identify potential serum biomarkers, thus providing direction to what usually is a laborious search for low abundance proteins.