TY  - JOUR
A1  - Franke, Katharina
A1  - Vilne, Baiba
A1  - da Costa, Olivia Prazeres
A1  - Rudelius, Martina
A1  - Peschel, Christian
A1  - Oostendorp, Robert A. J.
A1  - Keller, Ulrich
T1  - In vivo hematopoietic Myc activation directs a transcriptional signature in endothelial cells within the bone marrow microenvironment
JF  - Oncotarget
N2  - Cancer pathogenesis involves tumor-intrinsic genomic aberrations and tumor-cell extrinsic mechanisms such as failure of immunosurveillance and structural and functional changes in the microenvironment. Using Myc as a model oncogene we established a conditional mouse bone marrow transduction/transplantation model where the conditional activation of the oncoprotein Myc expressed in the hematopoietic system could be assessed for influencing the host microenvironment. Constitutive ectopic expression of Myc resulted in rapid onset of a lethal myeloproliferative disorder with a median survival of 21 days. In contrast, brief 4-day Myc activation by means of the estrogen receptor (ER) agonist tamoxifen did not result in gross changes in the percentage/frequency of hematopoietic lineages or hematopoietic stem/progenitor cell (HSPC) subsets, nor did Myc activation significantly change the composition of the non-hematopoietic microenvironment defined by phenotyping for CD31, ALCAM, and Sca-1 expression. Transcriptome analysis of endothelial CD45-Ter119-cells from tamoxifen-treated MycER bone marrow graft recipients revealed a gene expression signature characterized by specific changes in the Rho subfamily pathway members, in the transcription-translation-machinery and in angiogenesis. In conclusion, intra-hematopoietic Myc activation results in significant transcriptome alterations that can be attributed to oncogene-induced signals from hematopoietic cells towards the microenvironment, e. g. endothelial cells, supporting the idea that even pre-leukemic HSPC highjack components of the niche which then could protect and support the cancer-initiating population.
KW  - stem-cells
KW  - mutations
KW  - C-Myc
KW  - Rho-GTPases
KW  - niche
KW  - leukemia
KW  - target
KW  - growth
KW  - cycle
KW  - apoptosis, Myc
KW  - microenvironment
KW  - endothelial cells
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-145844
VL  - 6
IS  - 26
SP  - 21827
EP  - 21839
ER  - 
TY  - JOUR
A1  - Gewies, Andreas
A1  - Gorka, Oliver
A1  - Bergmann, Hanna
A1  - Pechloff, Konstanze
A1  - Petermann, Franziska
A1  - Jeltsch, Katharina M.
A1  - Rudelius, Martina
A1  - Kriegsmann, Mark
A1  - Weichert, Wilko
A1  - Horsch, Marion
A1  - Beckers, Johannes
A1  - Wurst, Wolfgang
A1  - Heikenwalder, Mathias
A1  - Korn, Thomas
A1  - Heissmeyer, Vigo
A1  - Ruland, Juergen
T1  - Uncoupling Malt1 Threshold Function from Paracaspase Activity Results in Destructive Autoimmune Inflammation
JF  - Cell Reports
N2  - The paracaspase Malt1 is a central regulator of antigen receptor signaling that is frequently mutated in human lymphoma. As a scaffold, it assembles protein complexes for NF-kappa B activation, and its proteolytic domain cleaves negative NF-kappa B regulators for signal enforcement. Still, the physiological functions of Malt1-protease are unknown. We demonstrate that targeted Malt1-paracaspase inactivation induces a lethal inflammatory syndrome with lymphocyte-dependent neurodegeneration in vivo. Paracaspase activity is essential for regulatory T cell (Treg) and innate-like B cell development, but it is largely dispensable for overcoming Malt1-dependent thresholds for lymphocyte activation. In addition to NF-kappa B inhibitors, Malt1 cleaves an entire set of mRNA stability regulators, including Roquin-1, Roquin-2, and Regnase-1, and paracaspase inactivation results in excessive interferon gamma (IFN gamma) production by effector lymphocytes that drive pathology. Together, our results reveal distinct threshold and modulatory functions of Malt1 that differentially control lymphocyte differentiation and activation pathways and demonstrate that selective paracaspase blockage skews systemic immunity toward destructive autoinflammation.
KW  - helper T-cells
KW  - combined immunodeficiency
KW  - messenger RNA
KW  - roquin
KW  - mice
KW  - NF-KAPPA-B
KW  - lymphoid-tissue
KW  - activation
KW  - cleavage
KW  - mutations
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-114627
VL  - 9
IS  - 4
ER  -