@article{RascheDuellMorgneretal.2013, author = {Rasche, Leo and Duell, Johannes and Morgner, Charlotte and Chatterjee, Manik and Hensel, Frank and Rosenwald, Andreas and Einsele, Hermann and Topp, Max S. and Br{\"a}ndlein, Stephanie}, title = {The Natural Human IgM Antibody PAT-SM6 Induces Apoptosis in Primary Human Multiple Myeloma Cells by Targeting Heat Shock Protein GRP78}, series = {PLoS ONE}, volume = {8}, journal = {PLoS ONE}, number = {5}, doi = {10.1371/journal.pone.0063414}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130125}, pages = {e63414}, year = {2013}, abstract = {In contrast to other haematological malignancies, targeted immunotherapy has not entered standard treatment regimens for de novo or relapsed multiple myeloma (MM) yet. While a number of IgG-formatted monoclonal antibodies are currently being evaluated in clinical trials in MM, our study aimed to investigate whether the fully human IgM monoclonal antibody PAT-SM6 that targets a tumour-specific variant of the heat shock protein GRP78 might be an attractive candidate for future immunotherapeutic approaches. We here show that GRP78 is stably and consistently expressed on the surface on tumour cells from patients with de novo, but also relapsed MM and that binding of PAT-SM6 to MM cells can specifically exert cytotoxic effects on malignant plasma cells, whereas non-malignant cells are not targeted. We demonstrate that the induction of apoptosis and, to a lesser extent, complement dependent cytotoxicity is the main mode of action of PAT-SM6, whereas antibody dependent cellular cytotoxicity does not appear to contribute to the cytotoxic properties of this antibody. Given the favourable safety profile of PAT-SM6 in monkeys, but also in a recent phase I trial in patients with malignant melanoma, our results form the basis for a planned phase I study in patients with relapsed MM.}, language = {en} } @article{LeichWeissbachKleinetal.2013, author = {Leich, E. and Weißbach, S. and Klein, H.-U. and Grieb, T. and Pischimarov, J. and St{\"u}hmer, T. and Chatterjee, M. and Steinbrunn, T. and Langer, C. and Eilers, M. and Knop, S. and Einsele, H. and Bargou, R. and Rosenwald, A.}, title = {Multiple myeloma is affected by multiple and heterogeneous somatic mutations in adhesion- and receptor tyrosine kinase signaling molecules}, series = {Blood Cancer Journal}, volume = {3}, journal = {Blood Cancer Journal}, number = {e102}, doi = {10.1038/bcj.2012.47}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128663}, year = {2013}, abstract = {Multiple myeloma (MM) is a largely incurable plasma cell malignancy with a poorly understood and heterogeneous clinical course. To identify potential, functionally relevant somatic mutations in MM, we performed whole-exome sequencing of five primary MM, corresponding germline DNA and six MM cell lines, and developed a bioinformatics strategy that also integrated published mutational data of 38 MM patients. Our analysis confirms that identical, recurrent mutations of single genes are infrequent in MM, but highlights that mutations cluster in important cellular pathways. Specifically, we show enrichment of mutations in adhesion molecules of MM cells, emphasizing the important role for the interaction of the MM cells with their microenvironment. We describe an increased rate of mutations in receptor tyrosine kinases (RTKs) and associated signaling effectors, for example, in EGFR, ERBB3, KRAS and MAP2K2, pointing to a role of aberrant RTK signaling in the development or progression of MM. The diversity of mutations affecting different nodes of a particular signaling network appears to be an intrinsic feature of individual MM samples, and the elucidation of intra- as well as interindividual redundancy in mutations that affect survival pathways will help to better tailor targeted therapeutic strategies to the specific needs of the MM patient.}, language = {en} }