Proteomic Comparison of Malignant Human Germ Cell Tumor Cell Lines

• Published in: Disease markers 2019, Vol.2019 (2019), p.1-14
• Main Authors: Behnes, Carl Ludwig, Radzun, Heinz Joachim, Ströbel, Philipp, Balabanov, Stefan, Honecker, Friedemann, Maatoug, Yasmine, Strauss, Arne, Urlaub, Henning, Serve, Hubert, Oellerich, Thomas, Küffer, Stefan, Bohnenberger, Hanibal, Bremmer, F., Oing, Christoph
• Format: Article
• Language: English
• Subjects: Amino acids; Biomarkers; Biotechnology; Cancer; Cancer therapies; CD81 antigen; Cell culture; Cell Culture Techniques - standards; Cell cycle; Cell Line, Tumor - classification; Comparative analysis; Ethylenediaminetetraacetic acid; Formaldehyde; Gene expression; Health aspects; Humans; Immunohistochemistry; Kinases; Labeling; Male; Mass spectrometry; Mass spectroscopy; Neoplasms, Germ Cell and Embryonal - genetics; Neoplasms, Germ Cell and Embryonal - metabolism; Paraffin; Paraffins; Pathology; Phosphatase; Proteins; Proteome; Seminoma; siRNA; Stable isotopes; Stem cells; Testicular Neoplasms - genetics; Testicular Neoplasms - metabolism; Testis - metabolism; Tumor cell lines; Tumors
• ISSN: 0278-0240; 1875-8630
• DOI: 10.1155/2019/8298524

Malignant germ cell tumors (GCT) are the most common malignant tumors in young men between 18 and 40 years. The correct identification of histological subtypes, in difficult cases supported by immunohistochemistry, is essential for therapeutic management. Furthermore, biomarkers may help to understand pathophysiological processes in these tumor types. Two GCT cell lines, TCam-2 with seminoma-like characteristics, and NTERA-2, an embryonal carcinoma-like cell line, were compared by a quantitative proteomic approach using high-resolution mass spectrometry (MS) in combination with stable isotope labelling by amino acid in cell culture (SILAC). We were able to identify 4856 proteins and quantify the expression of 3936. 347 were significantly differentially expressed between the two cell lines. For further validation, CD81, CBX-3, PHF6, and ENSA were analyzed by western blot analysis. The results confirmed the MS results. Immunohistochemical analysis on 59 formalin-fixed and paraffin-embedded (FFPE) normal and GCT tissue samples (normal testis, GCNIS, seminomas, and embryonal carcinomas) of these proteins demonstrated the ability to distinguish different GCT subtypes, especially seminomas and embryonal carcinomas. In addition, siRNA-mediated knockdown of these proteins resulted in an antiproliferative effect in TCam-2, NTERA-2, and an additional embryonal carcinoma-like cell line, NCCIT. In summary, this study represents a proteomic resource for the discrimination of malignant germ cell tumor subtypes and the observed antiproliferative effect after knockdown of selected proteins paves the way for the identification of new potential drug targets.