Molecular Biomarkers: Overview, Technologies and Strategies

Biomarkers play major roles in biomedicine. With the advancement of technologies and knowledge about the molecular mechanisms of disease initiation, development, and progression, biomarkers have been defined differently. For all practical purposes we have defined biomarkers as indicators of the biological state at specific time which can be measured and evaluated as indicators of biological processes, pathogenic states, pharmacological responses and therapeutic and intervention processes. We have selected few diseases (immune diseases, cardiovascular diseases, metabolomic diseases, infectious diseases, neurological diseases and cancer) to emphasize the significance of biomarkers in disease diagnosis and therapeutics. Omics technology (genomics, epigenomics, proteomics, metabolomics, transcriptomics etc.)-based potential biomarkers for better risk assessment, diagnosis, treatment and patient care (survival) are described. The significances of non-invasive biomarkers over invasive biomarkers and the potential of biomarkers in personalized medicine and genomics are also discussed. Due to the large amount of data, we have divided the contents into two chapters. In this first section we have given an overview of molecular biomarkers followed by types, discovery techniques and markers derived by such techniques for the selected diseases. In the next chapter we will discuss the challenges in biomarker discovery and the clinical implications of omics-based next-generation biomarkers. We believe that this chapter and the one that follows will be helpful to students and clinicians, as well as persons interested in cancer biomarkers.