title: MALDI tissue imaging: from biomarker discovery to clinical applications.
abstract: 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.
authors.affiliation: Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, VA 23507, USA.
authors.forename: Lisa H
authors.initials: LH
authors.lastname: Cazares
authors.forename: Dean A
authors.initials: DA
authors.lastname: Troyer
authors.forename: Binghe
authors.initials: B
authors.lastname: Wang
authors.forename: Richard R
authors.initials: RR
authors.lastname: Drake
authors.forename: O John
authors.initials: OJ
authors.lastname: Semmes
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000032:analysis; D003952:Diagnostic Imaging / Q000379:methods* / Q000639:trends; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods* / Q000639:trends
chemical_list: D014408:Biomarkers, Tumor