Biomarkers, or biological markers, are indicators of a particular biological state or condition in the body, including normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. Biomarkers can be DNA, RNA, protein, or metabolite molecules. Biomarker molecules are obtained from biospecimens: samples of blood, other bodily fluids, or hard tissues, including tumors. Biomarkers can provide much information about many types of cancers.
Many biomarker molecules degrade very quickly if the biospecimens are not maintained at the appropriate temperature until they are analyzed. This is known as “pre-analytical variability.” High quality biomarker analysis can be obtained only from high quality biospecimens… biospecimens that have been acquired, fixed, and shipped under appropriate and reproducible conditions. In other words, Biomarker utility is only as good as biospecimen quality!