Proteomic approaches to biomarker discovery in prostate and bladder cancers

Proteomic technologies, including high resolution two-dimensional electroph oresis (2-DE), antibody/protein arrays, and advances in mass spectrometry ( MS), are providing the tools needed to discover and identify disease associ ated biomarkers. Although application of these technologies to search for p otential diagnostic/prognostic biomarkers asscociated with prostate and bla dder cancer have been somewhat limited to date, proteins either overexpress ed or underexpressed have been detected in both these urological cancers. R ecent advances in mass spectrometry, especially platforms that permit rapid "fingerprint" profiling of multiple biomarkers, and tandem mass spectromet ers for protein identification, will most assuredly enhance the discovery, identification, and characterization of potential cancer associated biomark ers. Furthermore, application of laser capture microdissection microscopes has provided a rapid and reproducible approach to procure pure populations of cells. This technology coupled to 2-DE and MS has significantly aided th e elucidation of the differential expression profiles between disease, beni gn and normal prostate and bladder cell populations. Finally, development a nd application of learning algorithms and bioinformatics to the data genera ted by these proteomic technologies will be essential in determining the cl inical potential of a protein biomarker. The purpose of this review is to p rovide the reader with an overview of the application of these technologies in the search and identification of potential diagnostic/prognostic biomar kers for prostate and bladder cancers.