Cancer biomarker discovery in saliva by mass spectrometry

The quest for biomarkers has been much pursued to aid in the early diagnosis, monitor post-treatment progress and development of targeted therapies. Nevertheless, the translation of biomarker discovery to clinical use has been limited due to multiple reasons such as the long path from discovery to clinical assays, limitation of samples and incoherent pipeline for biomarker development. To date, diagnosis of cancer has been based on biopsies and histological examinations and often becomes difficult to get repeated sampling from patients for confirmation. Consequently, it is important for clinical researchers to look at multiple body fluids and different molecular techniques to identify biomarkers. One such bodyfluid is saliva, which is easily and non-invasively collected and contains thousands of potential protein biomarkers. Moreover, recent advances in the sensitivity and specificity of mass spectrometry based proteomics hold great promise to identify potential biomarkers. This review presents an overview of the potential use of saliva and mass spectrometry for global discovery and validation of biomarkers