Abstract

Proteomics Approaches towards Early Detection and Diagnosis of Cancer

Abdelkrim Khadir and Ali Tiss

Early stage detection of cancer is the key to provide a better outcome for therapeutic intervention. Most routine screening and diagnosis tools for cancer lack sufficient sensitivity and/or specificity and sometimes they are invasive. Proteomic technologies hold recently great promise in the search of new clinical biomarkers for the early detection and diagnosis of cancer as well as the discovery of new therapeutic targets from accessible bio-specimens. They also have the potential for contributing to the better understanding of cancer biology and helping in making the right therapeutic decisions for patients. Whereas some proteomic approaches, such as the ones used for identifying proteins and analyzing their interaction and function, are well established, others, such as protein expression profiling for biomarker discovery and validation, are still suffering from robustness and reproducibility issues before being able to have their clinical applications in cancer. In this perspective, we attempt here to first, briefly summarize the various mass spectrometry (MS)-based proteomic approaches and techniques used in cancer studies, then we discuss the complexity and the critical steps in handling and processing biological samples, and finally, we focus on the most promising strategies and techniques which may shorten the way from bench to bedside in cancer proteomics. These include; directed proteomics approaches, such as targeting disease tissues and subcellular compartments, analysis of post-translational modifications of selected subsets of proteins, selective reaction monitoring quantitation, and ‘omics’ integration strategy. MS-based imaging of tissue biopsies and Surface Plasmon Resonance techniques coupled to MS will be also discussed as they emerged recently as promising applications for biomarker discovery and validation.