LAUSR

The tissue microarray (TMA) method allows high-throughput biomarker analysis of large cohorts of tissue samples. The method is used for diagnostic profiling, evaluation of predictive or prognostic biomarkers, detection of disease biology (for example, pathway activation), and target identification for novel therapy approaches. Only a small amount of representative tissue is needed. Nowadays, highly specific antibodies for a vast spectrum of targets are available. Thus, the possibilities of the tissue microarray method are not restricted to the immunohistochemical detection of protein expression but extended to the visualization of mutations, amplifications, and even gene translocations. If formalin-fixed paraffin-embedded (FFPE) tissue is available for a large patient cohort, efficient, and costeffective molecular profiling of tissue-based assays of large sample sizes is possible. Additionally, in combination with clinical data, completed TMA blocks allow the fast implementation of follow-up projects. TMAs are also increasingly used in routine pathology as companion diagnostic tests for specific therapies. Since its development in 1998 as collaborative work of the Institute of Pathology of the University of Basel and the National Human Genome Research Institute in Bethesda [1], the published tissue microarray method has become increasingly popular and to date the Pubmed database hosts over 10,000 publications employing this approach.