MALDI tissue imaging: from biomarker discovery to clinical applications

• Published in: Analytical and bioanalytical chemistry Vol. 401; no. 1; pp. 17 - 27
• Main Authors: Cazares, Lisa H., Troyer, Dean A., Wang, Binghe, Drake, Richard R., John Semmes, O.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-07-2011; Springer
• Subjects: Analytical Chemistry; Animals; Assaying; Biochemistry; Biomarkers, Tumor - analysis; Biomolecules; Cancer; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Diagnostic Imaging - methods; Diagnostic Imaging - trends; Diagnostic systems; Food Science; Humans; Imaging; Ionization; Laboratory Medicine; Male; Monitoring/Environmental Analysis; Multiplexing; Prostate cancer; Prostatic Neoplasms - diagnosis; Prostatic Neoplasms - pathology; Review; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - trends; Biomarker discovery; Matrix-assisted laser desorption ionization tissue imaging; Cancer
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-011-5003-6

Matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS) is a powerful tool for the generation of multidimensional spatial expression maps of biomolecules directly from a tissue section. From a clinical proteomics perspective, this method correlates molecular detail to histopathological changes found in patient-derived tissues, enhancing the ability to identify candidates for disease biomarkers. The unbiased analysis and spatial mapping of a variety of molecules directly from clinical tissue sections can be achieved through this method. Conversely, targeted IMS, by the incorporation of laser-reactive molecular tags onto antibodies, aptamers, and other affinity molecules, enables analysis of specific molecules or a class of molecules. In addition to exploring tissue during biomarker discovery, the integration of MALDI-IMS methods into existing clinical pathology laboratory practices could prove beneficial to diagnostics. Querying tissue for the expression of specific biomarkers in a biopsy is a critical component in clinical decision-making and such markers are a major goal of translational research. An important challenge in cancer diagnostics will be to assay multiple parameters in a single slide when tissue quantities are limited. The development of multiplexed assays that maximize the yield of information from a small biopsy will help meet a critical challenge to current biomarker research. This review focuses on the use of MALDI-IMS in biomarker discovery and its potential as a clinical diagnostic tool with specific reference to our application of this technology to prostate cancer.