Advances in clinical applications of tissue proteomics: opportunities and challenges.

Mass spectrometry (MS)-based proteomics assays provide unprecedented opportunities for determination of protein expression in tissues for clinical applications. Within the last few years a number of clinical assays have been established. These include multiplexed selected reaction monitoring based approaches to quantify protein targets of therapeutic agents in cancer tissues and bottom-up shotgun MS-based proteomics approaches to diagnose and classify protein deposition disorders such as amyloidosis. These examples highlight the vast potential of MS-based proteomics as analytical and descriptive tools for clinical diagnosis of human disease. However, a number of major challenges remain for broader application and acceptance of such technologies in routine clinical care.