@article{ElMeseryRosenthalRauertWunderlichetal.2019,
  author    = {El-Mesery, Mohamed and Rosenthal, Tina and Rauert-Wunderlich, Hilka and Schreder, Martin and St{\"u}hmer, Thorsten and Leich, Ellen and Schlosser, Andreas and Ehrenschwender, Martin and Wajant, Harald and Siegmund, Daniela},
  title     = {The NEDD8-activating enzyme inhibitor MLN4924 sensitizes a TNFR1+ subgroup of multiple myeloma cells for TNF-induced cell death},
  series = {Cell Death \& Disease},
  volume    = {10},
  journal   = {Cell Death \& Disease},
  doi       = {10.1038/s41419-019-1860-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226666},
  year      = {2019},
  abstract  = {The NEDD8-activating enzyme (NAE) inhibitor MLN4924 inhibits cullin-RING ubiquitin ligase complexes including the SKP1-cullin-F-box E3 ligase βTrCP. MLN4924 therefore inhibits also the βTrCP-dependent activation of the classical and the alternative NFĸB pathway. In this work, we found that a subgroup of multiple myeloma cell lines (e.g., RPMI-8226, MM.1S, KMS-12BM) and about half of the primary myeloma samples tested are sensitized to TNF-induced cell death by MLN4924. This correlated with MLN4924-mediated inhibition of TNF-induced activation of the classical NFκB pathway and reduced the efficacy of TNF-induced TNFR1 signaling complex formation. Interestingly, binding studies revealed a straightforward correlation between cell surface TNFR1 expression in multiple myeloma cell lines and their sensitivity for MLN4924/TNF-induced cell death. The cell surface expression levels of TNFR1 in the investigated MM cell lines largely correlated with TNFR1 mRNA expression. This suggests that the variable levels of cell surface expression of TNFR1 in myeloma cell lines are decisive for TNF/MLN4924 sensitivity. Indeed, introduction of TNFR1 into TNFR1-negative TNF/MLN4924-resistant KMS-11BM cells, was sufficient to sensitize this cell line for TNF/MLN4924-induced cell death. Thus, MLN4924 might be especially effective in myeloma patients with TNFR1+ myeloma cells and a TNFhigh tumor microenvironment.},
  language  = {en}
}
@article{SiegmundKumsEhrenschwenderetal.2016,
  author    = {Siegmund, Daniela and Kums, Juliane and Ehrenschwender, Martin and Wajant, Harald},
  title     = {Activation of TNFR2 sensitizes macrophages for TNFR1-mediated necroptosis},
  series = {Cell Death \& Disease},
  volume    = {7},
  journal   = {Cell Death \& Disease},
  doi       = {10.1038/cddis.2016.285},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-162317},
  pages     = {e2375},
  year      = {2016},
  abstract  = {Macrophages express TNFR1 as well as TNFR2 and are also major producers of tumor necrosis factor (TNF), especially upon contact with pathogen-associated molecular patterns. Consequently, TNF not only acts as a macrophage-derived effector molecule but also regulates the activity and viability of macrophages. Here, we investigated the individual contribution of TNFR1 and TNFR2 to TNF-induced cell death in macrophages. Exclusive stimulation of TNFR1 showed no cytotoxic effect whereas selective stimulation of TNFR2 displayed mild cytotoxicity. Intriguingly, the latter was strongly enhanced by the caspase inhibitor zVAD-fmk. The strong cytotoxic activity of TNFR2 in the presence of zVAD-fmk was reversed by necrostatin-1, indicating necroptotic cell death. TNFR1- and TNF-deficient macrophages turned out to be resistant against TNFR2-induced cell death. In addition, the cIAP-depleting SMAC mimetic BV6 also enforced TNF/TNFR1-mediated necroptotic cell death in the presence of zVAD-fmk. In sum, our data suggest a model in which TNFR2 sensitizes macrophages for endogenous TNF-induced TNFR1-mediated necroptosis by the known ability of TNFR2 to interfere with the survival activity of TRAF2-cIAP1/2 complexes.},
  language  = {en}
}
@article{KlingseisenEhrenschwenderHeigletal.2012,
  author    = {Klingseisen, Laura and Ehrenschwender, Martin and Heigl, Ulrike and Wajant, Harald and Hehlgans, Thomas and Sch{\"u}tze, Stefan and Schneider-Brachert, Wulf},
  title     = {E3-14.7K Is Recruited to TNF-Receptor 1 and Blocks TNF Cytolysis Independent from Interaction with Optineurin},
  series = {PLoS One},
  volume    = {7},
  journal   = {PLoS One},
  number    = {6},
  doi       = {10.1371/journal.pone.0038348},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-135687},
  pages     = {e38348},
  year      = {2012},
  abstract  = {Escape from the host immune system is essential for intracellular pathogens. The adenoviral protein E3-14.7K (14.7K) is known as a general inhibitor of tumor necrosis factor (TNF)-induced apoptosis. It efficiently blocks TNF-receptor 1 (TNFR1) internalization but the underlying molecular mechanism still remains elusive. Direct interaction of 14.7K and/or associated proteins with the TNFR1 complex has been discussed although to date not proven. In our study, we provide for the first time evidence for recruitment of 14.7K and the 14.7K interacting protein optineurin to TNFR1. Various functions have been implicated for optineurin such as regulation of receptor endocytosis, vesicle trafficking, regulation of the nuclear factor kappa B (NF-kappa B) pathway and antiviral signaling. We therefore hypothesized that binding of optineurin to 14.7K and recruitment of both proteins to the TNFR1 complex is essential for protection against TNF-induced cytotoxic effects. To precisely dissect the individual role of 14.7K and optineurin, we generated and characterized a 14.7K mutant that does not confer TNF-resistance but is still able to interact with optineurin. In H1299 and KB cells expressing 14.7K wild-type protein, neither decrease in cell viability nor cleavage of caspases was observed upon stimulation with TNF. In sharp contrast, cells expressing the non-protective mutant of 14.7K displayed reduced viability and cleavage of initiator and effector caspases upon TNF treatment, indicating ongoing apoptotic cell death. Knockdown of optineurin in 14.7K expressing cells did not alter the protective effect as measured by cell viability and caspase activation. Taken together, we conclude that optineurin despite its substantial role in vesicular trafficking, endocytosis of cell surface receptors and recruitment to the TNFR1 complex is dispensable for the 14.7K-mediated protection against TNF-induced apoptosis.},
  language  = {en}
}