The lack of fresh frozen tissue specimens and degradation of nucleic acids in archival tissue, as well as tumour heterogeneity, negatively impact cancer diagnostic services in pathology laboratories worldwide. Gene amplification and expression diagnostic testing using archival material or material that requires transportation to servicing laboratories, needs a more robust and accurate test adapted to current clinical workflow. Our research team optimised the use of a hybridization-based assay to quantify RNA in archival material using branched-DNA (bDNA) technology on magnetic beads. The technology is used to measure gene expression using a quick and multiplex method that can accurately classify breast cancer into the different molecular subtypes, omitting the subjectivity of interpretation inherent in imaging techniques. In addition, due to the low input of material required, heterogeneous tumours can be laser microdissected using Haematoxylin and Eosin (H&E) stained sections. This method has a wide range of possible applications including tumour classification with diagnostic potential and measurement of biomarkers in liquid biopsies, allowing better patient management and disease monitoring. In addition, quantitative measurement of biomarkers in archival material is useful in oncology research with access to libraries of clinically-annotated material allowing for the validation of potential biomarkers and their correlation with clinical outcome using retrospective studies.
