Comprehensive Profiling of the Cell Surface Proteome of Sy5Y Neuroblastoma Cells Yields a Subset of Proteins Associated with Tumor Differentiation

Abstract

Neuroblastoma tumors are derived from the neural crest and exhibit substantial phenotypic heterogeneity and various degrees of differentiation and maturation. The identification of new cell surface markers in neuroblastoma has relevance to disease classification and therapy. As a means to categorize neuroblastomas based on cell surface protein expression, we have obtained a comprehensive profile of the cell surface proteome of the MYCN nonamplified SH-SY5Y neuroblastoma cell line. Biotinylated cell surface proteins were captured using an avidin affinity column, fractionated by reversed-phase chromatography and subjected to in-depth analysis by LC-MS/MS. An extensive list of proteins was established and a subset of surface membrane proteins was assessed by immunohistochemistry in a set of neuroblastoma tissue microarrays. Among identified proteins tested, NCAM and CD147 exhibited increased expression in poorly differentiated tumors (p < 0.01 and <0.03, respectively). CD147 expression was previously associated with aggressive carcinomas but has not been described in neuroblastoma. This comprehensive neuroblastoma cell surface profile has identified novel potential markers for neuroblastoma classification and novel potential targets for therapy.

Surface Proteome of “Mycobacterium avium subsp. hominissuis” during the Early Stages of Macrophage Infection

“…The membrane impermeability and selective labeling of surface proteins with Sulfo-NHS-LC-Biotin has been demonstrated in a wide range of prokaryotic and eukaryotic cells (20,24,33). Because of the extensive washing required by the methodology used in this study, the detected proteins were expected to be firmly associated with the bacterial cell envelope.…”

Design of universal cancer vaccines using natural tumor vessel-specific antigens (SANTAVAC)

“…Correspondingly, because trypsin contains numerous impurities, including other types of proteases, differently degraded forms of trypsin, and trypsin autolysis products, 70 the identification of cell surface antigens derived from trypsin treatment requires complex analytical methods. 56,[70][71][72][73][74][75] However, the need for antigen identification is more relevant to the characterization of individual antigens than to vaccine production. It is important that highly purified trypsin be used in the preparation of cell surface proteins for vaccines.…”

Oncoproteomics of Neuroblastoma: A Blueprint for Future Progress

“…Alternatively, using a comparative two-dimensional peptide mapping strategy to analyze closely related nonmetastatic and metastatic cancer cell lines, Roesli et al identified the expression of a select cohort of intracellular proteins on the membrane of metastatic cells [37]. Lastly, Garcia and coworkers employed a biotinylation labeling technique to categorize cell surface protein expression on nonamplified MYCN NB cells [38]. While these studies are preclinical in nature, they underscore the importance of identifying a NB cell surface proteomic signature for a bone marrow-tropic phenotype.…”