This review discusses about the various aspects of the Tissue microarray (TMA) technology and its applications in modern molecular and clinical research. Tissue microarrays (TMAs) allow a rapid, cost-effective, high through-put analysis of thousands of molecular markers at nucleic acids or protein level (1). This is a recent innovation in the field of pathology. A microarray contains many small representative tissue samples from hundreds of different cases assembled on a single histological slide, and therefore allows high throughput analysis of multiple specimens at the same time. Various types of tumors, at various stages of disease progression can also be studied at a single platform, in identical conditions in less labor-intensive and cost-effective ways. Tissue microarrays are paraffin blocks produced by extracting cylindrical tissue cores from different paraffin donor blocks and re-embedding these into a single recipient (microarray) block at defined array coordinates. Using this technique, up to 1000 or more tissue samples can be arrayed into a single paraffin block. It can permit simultaneous analysis of molecular targets at the DNA, mRNA, and protein levels under identical, standardized conditions on a single glass slide, and also provide maximal preservation and use of limited and irreplaceable archival tissue samples(2). This versatile technique, in which data analysis is automated, facilitates retrospective and prospective human tissue studies. It is a practical and effective tool for high-throughput molecular analysis of tissues that is helping to identify new diagnostic and prognostic markers and targets in human cancers, and has a range of potential applications in basic research, prognostic oncology and drug discovery. This article summarizes the technical aspects of tissue microarray construction and sectioning, advantages, application, and limitations.
Keywords: Paraffin Blocks, Tissue microarray, Histology, Immunohistochemistry.