Prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) are glycoproteins secreted by prostate epithelial cells, and have a long clinical history of use as serum biomarkers of prostate cancers. These two proteins and many other prostatic-derived proteins are present at significantly higher concentrations in seminal plasma and expressed prostatic secretions (EPS) in urine following a digital rectal exam prostate massage. New advances in mass spectrometry instrumentation and techniques have fueled a renewed emphasis on characterizing alterations in glycan structures on proteins associated with cancers. Previous published studies on a handful of samples have suggested that the presence of different N-linked glycan structures on PSA and PAP could distinguish benign prostate diseases from prostate cancer. Our preliminary data on PSA and PAP glycans derived from large seminal plasma cohorts and comparisons of individual sample spots has confirmed this. A combination of multiple mass spectrometry and ELISA- based approaches to characterizing N-linked glycans derived from PSA and PAP in prostatic fluids are proposed. This approach specifically tests the hypothesis that multiple glycan structural changes are detectable and consistently occur on secreted prostatic proteins like PSA and PAP as prostate cancers progress in disease severity. Our approach represents a paradigm shift for prostate cancer biomarker strategies away from the traditional serum or tissue based sources. It also emphasizes the development of diagnostic assays based on the well described changes in carbohydrate expression of surface and secreted glycoproteins associated with the cancer phenotype. To accomplish these goals, we have assembled a synergistic collaborative team with expertise in prostate cancer translational research and proteomics combined with glycan analysis specialists. The requisite clinical samples, instrumentation and glycan analysis workflows are available to accomplish the following specific aims. 1) Identify N-linked glycan biomarkers on PAP and PSA in proximal prostatic fluids reflective of prostate cancer pathology and disease state. 2) The detection and pre-validation of prostate-disease specific PAP and PSA glycoforms in a large-scale cohort of EPS urines obtained after digital rectal exams. Specific sialic acid and fucose targeted lectin ELISAs will be developed. 3) Identify additional candidate prostatic disease glycoprotein biomarkers in the EPS sample cohort using iTRAQ comparisons, including a comprehensive profile of the glycan changes across disease states. We expect that characterization of the glycans on PSA and PAP will identify molecular markers that improve prostate cancer detection and risk stratification.

Public Health Relevance

The current strengths and limitations of the PSA serum test for early detection and treatment of prostate cancers are well documented, and it is clear new diagnostic biomarkers are needed for this disease. We propose to characterize cancer specific changes in the glycan components of proteins in fluids secreted by the prostate. Identification of these molecular markers will improve prostate cancer detection and risk stratification prior to biopsy and prostatectomy procedures.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
1R01CA135087-01A1
Application #
7657071
Study Section
Cancer Biomarkers Study Section (CBSS)
Program Officer
Kagan, Jacob
Project Start
2009-03-27
Project End
2013-01-31
Budget Start
2009-03-27
Budget End
2010-01-31
Support Year
1
Fiscal Year
2009
Total Cost
$254,480
Indirect Cost
Name
Eastern Virginia Medical School
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
058625146
City
Norfolk
State
VA
Country
United States
Zip Code
23501
Kim, Yunee; Jeon, Jouhyun; Mejia, Salvador et al. (2016) Targeted proteomics identifies liquid-biopsy signatures for extracapsular prostate cancer. Nat Commun 7:11906
Sundararaj, Kamala P; Thiyagarajan, Thirumagal; Molano, Ivan et al. (2015) FLI1 Levels Impact CXCR3 Expression and Renal Infiltration of T Cells and Renal Glycosphingolipid Metabolism in the MRL/lpr Lupus Mouse Strain. J Immunol 195:5551-60
Drake, Richard R; Jones, E Ellen; Powers, Thomas W et al. (2015) Altered glycosylation in prostate cancer. Adv Cancer Res 126:345-82
Venant, Heather; Rahmaniyan, Mehrdad; Jones, E Ellen et al. (2015) The Sphingosine Kinase 2 Inhibitor ABC294640 Reduces the Growth of Prostate Cancer Cells and Results in Accumulation of Dihydroceramides In Vitro and In Vivo. Mol Cancer Ther 14:2744-52
Nowling, Tamara K; Mather, Andrew R; Thiyagarajan, Thirumagal et al. (2015) Renal glycosphingolipid metabolism is dysfunctional in lupus nephritis. J Am Soc Nephrol 26:1402-13
Jones, Elizabeth Ellen; Gao, Peng; Smith, Charles D et al. (2015) Tissue biomarkers of drug efficacy: case studies using a MALDI-MSI workflow. Bioanalysis 7:2611-9
Jones, E Ellen; Dworski, Shaalee; Canals, Daniel et al. (2014) On-tissue localization of ceramides and other sphingolipids by MALDI mass spectrometry imaging. Anal Chem 86:8303-11
Drake, Richard R; Kislinger, Thomas (2014) The proteomics of prostate cancer exosomes. Expert Rev Proteomics 11:167-77
Powers, Thomas W; Neely, Benjamin A; Shao, Yuan et al. (2014) MALDI imaging mass spectrometry profiling of N-glycans in formalin-fixed paraffin embedded clinical tissue blocks and tissue microarrays. PLoS One 9:e106255
Jones, Elizabeth Ellen; Powers, Thomas W; Neely, Benjamin A et al. (2014) MALDI imaging mass spectrometry profiling of proteins and lipids in clear cell renal cell carcinoma. Proteomics 14:924-35

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