Focusing on the importance of proteins for the onset of a monoclonal gammopathy of undetermined significance (MGUS) and its progression into a multiple myeloma (MM), this thesis deals with proteomics of bone marrow plasma and blood serum. Quantitative changes of relevant proteins in disease progression could pave the way for suitable biomarkers indicating the malign transformation of an MGUS into an MM. Following depletion and tryptic in-solution
digestion, mass spectrometry of 6 MGUS, 12 MM and 6 control samples is performed via a shotgun LC-MS/MS approach using an orbitrap coupled with a liquid chromatography (LC) system. After identifying the detected proteins by means of a database, the application of two-sided t tests in Perseus reflects the significance of changes in protein concentrations. In this study, proteomics of bone marrow plasma and blood serum yield several significantly up-
and down-regulated proteins with pro-inflammatory and tumour progressive effects. These bioactive molecules may act in concert to alter cell metabolism, adhesion and signalling, which are likely to promote disease progression. However, biomarkers specifically indicating this transformation cannot be found. Nevertheless, the results point towards several mechanisms of clinical relevance regarding multiple myeloma and could provide a profound basis for further research.