MALDI Imaging of Tissue Microarrays Mass Spectrometry Identification of Tumor Proteome
A Seager, J Melamed, A Kogos, T Remsen, S Formenti, P Pevsner. NYU SOM, NY, NY
Background: Mass spectrometry of tissue microarrays (TMA) can characterize the proteome of multiple cancers. MALDI Imaging of tumors has been reported previously by the authors.1-3 Tentative protein identifications can be obtained with MALDI Imaging. We hypothesized that a TMA could provide specific protein characterization of tissue.
Design: Five m sections were obtained from a TMA composed of thirteen cores: prostate cancer (5), normal prostate (7), and control liver tissue (1), figure 1. Contiguous sections were obtained for MALDI imaging and H&E stain. Sinapic acid matrix for MALDI imaging was applied by sublimation. MALDI images were exported to BioMap, and the mass of the prominent proteins identified. Tentative protein indentifications were displayed as orange color on the MALDI images.
Results: All proteins were present in liver tissue. The proteins in tumor and normal tissue were estrogen receptor 13090.7 Da, hCG1984794 14884.1 Da, and immunoglobulin mu heavy chain16005.4 Da. The following proteins were only identified in normal tissue: L1 protein [Human papillomavirus type 6] 16679.7 Da,ORF1 protein[Hepatitis E virus]31258.5 Da,hCG1730597,isoform CRA_b 61541.8 Da, Solute carrier family17, member7 61541.8 Da, and hemagglutinin[Influenza B virus (B/Delaware/04/2007)] 63111.8 Da.
Conclusions: MALDI imaging can be used to identify proteins from a TMA. The expressed proteins can separate tumor from normal tissue. Further studies should allow increased resolution of MALDI images, and higher correlation with Gleason grade in prostate and malignancy grade in other tumors. 1. Pevsner PH, Melamed J, Remsen T, et al. Mass Spectrometry MALDI Imaging of Colon Cancer Biomarkers- A New Diagnostic Paradigm. Biomarkers in Medicine 2008 in Press;. 2. Pevsner P, Formenti S, Remsen T, et al. Mass Spectrometry of Buccal Mucosa. Biomarkers for Biodosimetry in Radiation Incidents 2008. Bethesda, MD 3. Pevsner PH, Naftolin F, Hillman DE, et al. Direct identification of proteins from T47D cells and murine brain tissue by matrix-assisted laser desorption/ionization post-source decay/collision-induced dissociation. Rapid Commun Mass Spectrom 2007;21:429-36.
Category: Special Category for 2009 - Pan-genomic/Pan-proteomic approaches to Cancer
Tuesday, March 10, 2009 9:30 AM
Poster Session III # 233, Tuesday Morning