TY  - THES
A1  - Hummel, Horst-Dieter
T1  - Herstellung und Evaluation genetisch veränderter Masernviren zur spezifischen Infektion und Elimination primärer maligner Plasmazellen
T1  - Genetically engineered attenuated measles virus specifically infects and kills primary multiple myeloma cells
N2  - Das Multiple Myelom ist trotz deutlicher Fortschritte in der Therapie meist eine unheilbare Erkrankung, so dass der Erforschung neuer therapeutischer Optionen mit dem Ziel, eine möglichst langfristige krankheitsfreie Zeit für den betroffenen Patienten zu erreichen, eine wichtige Bedeutung zukommt. Hierbei erweist sich der Ansatz, maligne Plasmazellen spezifisch mit onkolytischen Viren zu infizieren und zu eliminieren, als zunehmend vielversprechend. Im Rahmen dieser Arbeit wurde ein neues rekombinantes Masernvirus kloniert, das selektiv primäre MM-Zellen infiziert und abtötet. Diese Fähigkeit basiert auf der Verwendung eines mutierten H-Proteins, das nicht mehr mit den natürlichen Rezeptoren CD46 oder CD150 interagiert und das zusätzlich mit einem single chain Antikörper (scFvWue) verknüpft ist, der MM-Zellen spezifisch bindet. Unter Verwendung eines etablierten Rescuesystems aus cDNA konnten in vitro replikationskompetente Virionen von MV-Wue erstellt werden. Diese vorgenommenen Veränderungen beeinflussten die Fähigkeit zur effizienten Replikation und Produktion infektiöser Viren in vitro nicht. Zur funktionellen Testung des neuen rekombinanten Virus MV-Wue wurde die Spezifität des Virus für primäre maligne Plasmazellen in Infektionsexperimenten gezeigt sowie der Mechanismus der Ablation als Apoptose definiert.
N2  - The applicability of cytoreductive treatment of malignant diseases using recombinant viruses strongly depends on specific recognition of surface receptors to target exclusively neoplastic cells. A recently generated monoclonal antibody (mAb), Wue-1, specifically detects CD138(+) multiple myeloma (MM) cells. In this study, a haemagglutinin (H) protein that was receptor-blinded (i.e. did not bind to CD46 and CD150) was genetically re-engineered by fusing it to a single-chain antibody fragment (scFv) derived from the Wue-1 mAb open reading frame (scFv-Wue), resulting in the recombinant retargeted measles virus (MV)-Wue. MV-Wue efficiently targeted and fully replicated in primary MM cells, reaching titres similar to those seen with non-retargeted viruses. In agreement with its altered receptor specificity, infection of target cells was no longer dependent on CD150 or CD46, but was restricted to cells that had been labelled with Wue-1 mAb. Importantly, infection with MV-Wue rapidly induced apoptosis in CD138(+) malignant plasma cell targets. MV-Wue is the first fully retargeted MV using the restricted interaction between Wue-1 mAb and primary MM cells specifically to infect, replicate in and deplete malignant plasma cells.
KW  - Multiples Myelom
KW  - Masernvirus
KW  - retardeted virus
KW  - Wue-1
KW  - multiple myeloma
KW  - retargeted measles virus
KW  - Wue-1
Y1  - 2010
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-51393
ER  - 
TY  - JOUR
A1  - Weißbach, Susann
A1  - Heredia-Guerrero, Sofia Catalina
A1  - Barnsteiner, Stefanie
A1  - Großhans, Lukas
A1  - Bodem, Jochen
A1  - Starz, Hanna
A1  - Langer, Christian
A1  - Appenzeller, Silke
A1  - Knop, Stefan
A1  - Steinbrunn, Torsten
A1  - Rost, Simone
A1  - Einsele, Hermann
A1  - Bargou, Ralf Christian
A1  - Rosenwald, Andreas
A1  - Stühmer, Thorsten
A1  - Leich, Ellen
T1  - Exon-4 Mutations in KRAS Affect MEK/ERK and PI3K/AKT Signaling in Human Multiple Myeloma Cell Lines
JF  - Cancers
N2  - Approximately 20% of multiple myeloma (MM) cases harbor a point mutation in KRAS. However, there is still no final consent on whether KRAS-mutations are associated with disease outcome. Specifically, no data exist on whether KRAS-mutations have an impact on survival of MM patients at diagnosis in the era of novel agents. Direct blockade of KRAS for therapeutic purposes is mostly impossible, but recently a mutation-specific covalent inhibitor targeting KRAS\(^{p.G12C}\) entered into clinical trials. However, other KRAS hotspot-mutations exist in MM patients, including the less common exon-4 mutations. For the current study, the coding regions of KRAS were deep-sequenced in 80 newly diagnosed MM patients, uniformely treated with three cycles of bortezomib plus dexamethasone and cyclophosphamide (VCD)-induction, followed by high-dose chemotherapy and autologous stem cell transplantation. Moreover, the functional impact of KRAS\(^{p.G12A}\) and the exon-4 mutations p.A146T and p.A146V on different survival pathways was investigated. Specifically, KRAS\(^{WT}\), KRAS\(^{p.G12A}\), KRAS\(^{p.A146T}\), and KRAS\(^{p.A146V}\) were overexpressed in HEK293 cells and the KRAS\(^{WT}\) MM cell lines JJN3 and OPM2 using lentiviral transduction and the Sleeping Beauty vector system. Even though KRAS-mutations were not correlated with survival, all KRAS-mutants were found capable of potentially activating MEK/ERK- and sustaining PI3K/AKT-signaling in MM cells.
KW  - multiple myeloma
KW  - KRAS
KW  - MEK/ERK-signaling
KW  - AKT-signaling
KW  - amplicon sequencing
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200617
SN  - 2072-6694
VL  - 12
IS  - 2
ER  -