Use of High-Throughput DNA Microarrays to Identify Biomarkers for Bladder Cancer

Numerous markers have been described to correlate to some extent with tumor stage and prognosis of patients with bladder cancer. The power of many of these biomarkers in detecting superficial disease or predicting the clinical outcome of individual tumors is limited, and alternative markers are still in demand. High-throughput microarrays represent novel means for cancer research and tumor marker discovery. The aim of this report was to discuss the application of DNA technologies to provide novel biomarkers for bladder cancer. Specific bladder tumor subtypes have distinct gene expression profiles. The use of high-throughput DNA microarrays allows identification of the most prevalent and relevant alterations within bladder tumors. Clusters of differentially expressed genes will become biomarkers to discriminate subgroups of patients with different histopathology or clinical outcome. Additionally, the identified individual molecular targets might be further validated and developed into novel serum or urinary biomarkers for the diagnosis and/or as prognostic factors to be applied in clinical practice. The diagnosis and prognosis of bladder cancer would be enhanced by the use of such markers, and the marker itself may constitute a therapeutic target when studied in appropriate patients and control groups. Expression profiling with high-throughput DNA microarrays has the potential of providing critical clues for the management of bladder cancer patients. As the quality, standardization, and ease of use of the technology increase and the costs decrease, DNA microarrays will move from being a technology restricted to research to clinical laboratories in the near future.