@article{BrieseSaalBauernschubertLueningschroeretal.2020, author = {Briese, Michael and Saal-Bauernschubert, Lena and L{\"u}ningschr{\"o}r, Patrick and Moradi, Mehri and Dombert, Benjamin and Surrey, Verena and Appenzeller, Silke and Deng, Chunchu and Jablonka, Sibylle and Sendtner, Michael}, title = {Loss of Tdp-43 disrupts the axonal transcriptome of motoneurons accompanied by impaired axonal translation and mitochondria function}, series = {Acta Neuropathologica Communications}, volume = {8}, journal = {Acta Neuropathologica Communications}, doi = {10.1186/s40478-020-00987-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230322}, year = {2020}, abstract = {Protein inclusions containing the RNA-binding protein TDP-43 are a pathological hallmark of amyotrophic lateral sclerosis and other neurodegenerative disorders. The loss of TDP-43 function that is associated with these inclusions affects post-transcriptional processing of RNAs in multiple ways including pre-mRNA splicing, nucleocytoplasmic transport, modulation of mRNA stability and translation. In contrast, less is known about the role of TDP-43 in axonal RNA metabolism in motoneurons. Here we show that depletion of Tdp-43 in primary motoneurons affects axon growth. This defect is accompanied by subcellular transcriptome alterations in the axonal and somatodendritic compartment. The axonal localization of transcripts encoding components of the cytoskeleton, the translational machinery and transcripts involved in mitochondrial energy metabolism were particularly affected by loss of Tdp-43. Accordingly, we observed reduced protein synthesis and disturbed mitochondrial functions in axons of Tdp-43-depleted motoneurons. Treatment with nicotinamide rescued the axon growth defect associated with loss of Tdp-43. These results show that Tdp-43 depletion in motoneurons affects several pathways integral to axon health indicating that loss of TDP-43 function could thus make a major contribution to axonal pathomechanisms in ALS.}, language = {en} } @article{JessenKressBaluapurietal.2020, author = {Jessen, Christina and Kreß, Julia K. C. and Baluapuri, Apoorva and Hufnagel, Anita and Schmitz, Werner and Kneitz, Susanne and Roth, Sabine and Marquardt, Andr{\´e} and Appenzeller, Silke and Ade, Casten P. and Glutsch, Valerie and Wobser, Marion and Friedmann-Angeli, Jos{\´e} Pedro and Mosteo, Laura and Goding, Colin R. and Schilling, Bastian and Geissinger, Eva and Wolf, Elmar and Meierjohann, Svenja}, title = {The transcription factor NRF2 enhances melanoma malignancy by blocking differentiation and inducing COX2 expression}, series = {Oncogene}, volume = {39}, journal = {Oncogene}, issn = {0950-9232}, doi = {10.1038/s41388-020-01477-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235064}, pages = {6841-6855}, year = {2020}, abstract = {The transcription factor NRF2 is the major mediator of oxidative stress responses and is closely connected to therapy resistance in tumors harboring activating mutations in the NRF2 pathway. In melanoma, such mutations are rare, and it is unclear to what extent melanomas rely on NRF2. Here we show that NRF2 suppresses the activity of the melanocyte lineage marker MITF in melanoma, thereby reducing the expression of pigmentation markers. Intriguingly, we furthermore identified NRF2 as key regulator of immune-modulating genes, linking oxidative stress with the induction of cyclooxygenase 2 (COX2) in an ATF4-dependent manner. COX2 is critical for the secretion of prostaglandin E2 and was strongly induced by H\(_2\)O\(_2\) or TNFα only in presence of NRF2. Induction of MITF and depletion of COX2 and PGE2 were also observed in NRF2-deleted melanoma cells in vivo. Furthermore, genes corresponding to the innate immune response such as RSAD2 and IFIH1 were strongly elevated in absence of NRF2 and coincided with immune evasion parameters in human melanoma datasets. Even in vitro, NRF2 activation or prostaglandin E2 supplementation blunted the induction of the innate immune response in melanoma cells. Transcriptome analyses from lung adenocarcinomas indicate that the observed link between NRF2 and the innate immune response is not restricted to melanoma.}, language = {en} } @article{WeissbachHerediaGuerreroBarnsteineretal.2020, author = {Weißbach, Susann and Heredia-Guerrero, Sofia Catalina and Barnsteiner, Stefanie and Großhans, Lukas and Bodem, Jochen and Starz, Hanna and Langer, Christian and Appenzeller, Silke and Knop, Stefan and Steinbrunn, Torsten and Rost, Simone and Einsele, Hermann and Bargou, Ralf Christian and Rosenwald, Andreas and St{\"u}hmer, Thorsten and Leich, Ellen}, title = {Exon-4 Mutations in KRAS Affect MEK/ERK and PI3K/AKT Signaling in Human Multiple Myeloma Cell Lines}, series = {Cancers}, volume = {12}, journal = {Cancers}, number = {2}, issn = {2072-6694}, doi = {10.3390/cancers12020455}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200617}, year = {2020}, abstract = {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.}, language = {en} }