@phdthesis{Anany2019,
  author    = {Anany, Mohamed Ahmed Mohamed Mohamed},
  title     = {Enhancement of Toll-like receptor3 (TLR3)-induced death signaling by TNF-like weak inducer of apoptosis (TWEAK)},
  doi       = {10.25972/OPUS-18975},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-189757},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2019},
  abstract  = {Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) is a member of the TNF superfamily (TNFSF) and is as such initially expressed as type II class transmembrane glycoprotein from which a soluble ligand form can be released by proteolytic processing. While the expression of TWEAK has been detected at the mRNA level in various cell lines and cell types, its cell surface expression has so far only been documented for dendritic cells, monocytes and interferon-γ stimulated NK cells. The fibroblast growth factor-inducible-14 (Fn14) is a TRAF2-interacting receptor of the TNF receptor superfamily (TNFRSF) and is the only receptor for TWEAK. The expression of Fn14 is strongly induced in a variety of non-hematopoietic cell types after tissue injury. The TWEAK/Fn14 system induces pleiotropic cellular activities such as induction of proinflammatory genes, stimulation of cellular angiogenesis, proliferation, differentiation, migration and in rare cases induction of apoptosis. On the other side, Toll-like receptor3 (TLR3) is one of DNA- and RNA-sensing pattern recognition receptors (PRRs), plays a crucial role in the first line of defense against virus and invading foreign pathogens and cancer cells. Polyinosinic-polycytidylic acid poly(I:C) is a synthetic analog of dsRNA, binds to TLR3 which acts through the adapter TRIF/TICAM1, leading to cytokine secretion, NF-B activation, IRF3 nuclear translocation, inflammatory response and may also elicit the cell death. TWEAK sensitizes cells for TNFR1-induced apoptosis and necroptosis by limiting the availability of protective TRAF2-cIAP1 and TRAF2-cIAP2 complexes, which interact with the TNFR1-binding proteins TRADD and RIPK1. In accordance with the fact that poly(I:C)-induced signaling also involves these proteins, we found enhanced necroptosis-induction in HaCaT and HeLa-RIPK3 by poly(I:C) in the presence of TWEAK (Figure 24). Analysis of a panel of TRADD, FADD, RIPK1 and caspase-8 knockout cells revealed furthermore similarities and differences in the way how these molecules act in cell death signaling by poly(I:C)/TWEAK and TNF and TRAIL. RIPK1 turned out to be essential for poly(I:C)/TWEAK-induced caspase-8-mediated apoptosis but was dispensable for these responses in TNF and TRAIL signaling. Lack of FADD protein abrogated TRAIL- but not TNF- and poly(I:C)-induced necroptosis. Moreover, we observed that both long and short FLIP rescued HaCaT and HeLa-RIPK3 cells from poly(I:C)-induced apoptosis or necroptosis. To sum up, our results demonstrate that TWEAK, which is produced by interferon stimulated myeloid cells, controls the induction of apoptosis and necroptosis by the TLR3 ligand poly(I:C) and may thus contribute to cancer or anti-viral immunity treatment.},
  subject      = {Immunologe},
  language  = {en}
}
@article{CarmonaAranaSeherNeumannetal.2014,
  author    = {Carmona Arana, Jos{\´e} Antonio and Seher, Axel and Neumann, Manfred and Lang, Isabell and Siegmund, Daniela and Wajant, Harald},
  title     = {TNF Receptor-Associated Factor 1 is a Major Target of Soluble TWEAK},
  series = {Frontiers in Immunology},
  volume    = {5},
  journal   = {Frontiers in Immunology},
  number    = {63},
  issn      = {1664-3224},
  doi       = {10.3389/fimmu.2014.00063},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120620},
  year      = {2014},
  abstract  = {Soluble tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK), in contrast to membrane TWEAK and TNF, is only a weak activator of the classical NFκB pathway. We observed that soluble TWEAK was regularly more potent than TNF with respect to the induction of TNF receptor-associated factor 1 (TRAF1), a NFκB-controlled signaling protein involved in the regulation of inflammatory signaling pathways. TNF-induced TRAF1 expression was efficiently blocked by inhibition of the classical NFκB pathway using the IKK2 inhibitor, TPCA1. In contrast, in some cell lines, TWEAK-induced TRAF1 production was only partly inhibited by TPCA1. The NEDD8-activating enzyme inhibitor MLN4924, however, which inhibits classical and alternative NFκB signaling, blocked TNF- and TWEAK-induced TRAF1 expression. This suggests that TRAF1 induction by soluble TWEAK is based on the cooperative activity of the two NFκB signaling pathways. We have previously shown that oligomerization of soluble TWEAK results in ligand complexes with membrane TWEAK-like activity. Oligomerization of soluble TWEAK showed no effect on the dose response of TRAF1 induction, but potentiated the ability of soluble TWEAK to trigger production of the classical NFκB-regulated cytokine IL8. Transfectants expressing soluble TWEAK and membrane TWEAK showed similar induction of TRAF1 while only the membrane TWEAK expressing cells robustly stimulated IL8 production. These data indicate that soluble TWEAK may efficiently induce a distinct subset of the membrane TWEAK-targeted genes and argue again for a crucial role of classical NFκB pathway-independent signaling in TWEAK-induced TRAF1 expression. Other TWEAK targets, which can be equally well induced by soluble and membrane TWEAK, remain to be identified and the relevance of the ability of soluble TWEAK to induce such a distinct subset of membrane TWEAK-targeted genes for TWEAK biology will have to be clarified in future studies.},
  language  = {en}
}
@phdthesis{Roos2009,
  author    = {Roos, Claudia},
  title     = {Characterization of tumor necrosis factor-like weak inducer of apoptosis (TWEAK)-induced signaling pathways},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-45295},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2009},
  abstract  = {TWEAK ist ein typischer Vertreter der TNF Ligandenfamilie. TWEAK wird als Typ II Transmembranprotein exprimiert, kann jedoch durch proteolytische Prozessierung auch als l{\"o}sliches Protein freigesetzt werden. In dieser Arbeit wird gezeigt, dass oligomerisiertes TWEAK in Hinblick auf die Aktivierung des klassischen NF\&\#954;B Signalweges deutlich aktiver ist als l{\"o}sliches, trimeres TWEAK. Jedoch sind beide TWEAK-Varianten in der Lage, die Depletion von TRAF2 und die Prozessierung von p100, beides Kennzeichen f{\"u}r die Aktivierung des alternativen NF\&\#954;B Signalweges, zu induzieren. Ebenso wie andere l{\"o}sliche TNF-Liganden, die ihren entsprechenden Rezeptor nur schwach aktivieren, erlangt l{\"o}sliches TWEAK durch Oligomerisierung vergleichbare Aktivit{\"a}t zum membrangebundenen Liganden. TRAF2 spielt eine Schl{\"u}sselrolle in der TWEAK-vermittelten NF\&\#954;B Aktivierung. Durch Depletion oder Degradation von TRAF2 f{\"a}llt die Entscheidung, ob lediglich der alternative oder beide, der klassische und der alternative NF\&\#954;B Signalweg aktiviert werden. Die Blockade des TWEAK-Rezeptors Fn14 inhibiert die Aktivierung der NF\&\#954;B Signalwege, ungeachtet welche Form von TWEAK zur Stimulation genutzt wird. Das weist darauf hin, dass die unterschiedlichen Aktivit{\"a}ten der beiden TWEAK-Varianten in der Induktion des klassischen und alternativen NF\&\#954;B Signalweges nicht durch die Nutzung verschiedener Rezeptoren verursacht sind. Damit wird in dieser Arbeit anhand von TWEAK zum ersten mal gezeigt, dass ein TNF Ligand in unterschiedlichen Varianten qualitativ unterschiedliche Aktivit{\"a}ten des entsprechenden TNF Rezeptors ausl{\"o}st.},
  subject      = {Tumor-Nekrose-Faktor},
  language  = {en}
}
@article{SiegmundZaitsevaWajant2023,
  author    = {Siegmund, Daniela and Zaitseva, Olena and Wajant, Harald},
  title     = {Fn14 and TNFR2 as regulators of cytotoxic TNFR1 signaling},
  series = {Frontiers in Cell and Developmental Biology},
  volume    = {11},
  journal   = {Frontiers in Cell and Developmental Biology},
  issn      = {2296-634X},
  doi       = {10.3389/fcell.2023.1267837},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-354304},
  year      = {2023},
  abstract  = {Tumor necrosis factor (TNF) receptor 1 (TNFR1), TNFR2 and fibroblast growth factor-inducible 14 (Fn14) belong to the TNF receptor superfamily (TNFRSF). From a structural point of view, TNFR1 is a prototypic death domain (DD)-containing receptor. In contrast to other prominent death receptors, such as CD95/Fas and the two TRAIL death receptors DR4 and DR5, however, liganded TNFR1 does not instruct the formation of a plasma membrane-associated death inducing signaling complex converting procaspase-8 into highly active mature heterotetrameric caspase-8 molecules. Instead, liganded TNFR1 recruits the DD-containing cytoplasmic signaling proteins TRADD and RIPK1 and empowers these proteins to trigger cell death signaling by cytosolic complexes after their release from the TNFR1 signaling complex. The activity and quality (apoptosis versus necroptosis) of TNF-induced cell death signaling is controlled by caspase-8, the caspase-8 regulatory FLIP proteins, TRAF2, RIPK1 and the RIPK1-ubiquitinating E3 ligases cIAP1 and cIAP2. TNFR2 and Fn14 efficiently recruit TRAF2 along with the TRAF2 binding partners cIAP1 and cIAP2 and can thereby limit the availability of these molecules for other TRAF2/cIAP1/2-utilizing proteins including TNFR1. Accordingly, at the cellular level engagement of TNFR2 or Fn14 inhibits TNFR1-induced RIPK1-mediated effects reaching from activation of the classical NFκB pathway to induction of apoptosis and necroptosis. In this review, we summarize the effects of TNFR2- and Fn14-mediated depletion of TRAF2 and the cIAP1/2 on TNFR1 signaling at the molecular level and discuss the consequences this has in vivo.},
  language  = {en}
}
@article{ZaitsevaHoffmannOttoetal.2022,
  author    = {Zaitseva, Olena and Hoffmann, Annett and Otto, Christoph and Wajant, Harald},
  title     = {Targeting fibroblast growth factor (FGF)-inducible 14 (Fn14) for tumor therapy},
  series = {Frontiers in Pharmacology},
  volume    = {13},
  journal   = {Frontiers in Pharmacology},
  issn      = {1663-9812},
  doi       = {10.3389/fphar.2022.935086},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-290238},
  year      = {2022},
  abstract  = {Fibroblast growth factor-inducible 14 (Fn14) is a member of the tumor necrosis factor (TNF) receptor superfamily (TNFRSF) and is activated by its ligand TNF-like weak inducer of apoptosis (TWEAK). The latter occurs as a homotrimeric molecule in a soluble and a membrane-bound form. Soluble TWEAK (sTWEAK) activates the weakly inflammatory alternative NF-κB pathway and sensitizes for TNF-induced cell death while membrane TWEAK (memTWEAK) triggers additionally robust activation of the classical NF-κB pathway and various MAP kinase cascades. Fn14 expression is limited in adult organisms but becomes strongly induced in non-hematopoietic cells by a variety of growth factors, cytokines and physical stressors (e.g., hypoxia, irradiation). Since all these Fn14-inducing factors are frequently also present in the tumor microenvironment, Fn14 is regularly found to be expressed by non-hematopoietic cells of the tumor microenvironment and most solid tumor cells. In general, there are three possibilities how the tumor-Fn14 linkage could be taken into consideration for tumor therapy. First, by exploitation of the cancer associated expression of Fn14 to direct cytotoxic activities (antibody-dependent cell-mediated cytotoxicity (ADCC), cytotoxic payloads, CAR T-cells) to the tumor, second by blockade of potential protumoral activities of the TWEAK/Fn14 system, and third, by stimulation of Fn14 which not only triggers proinflammtory activities but also sensitizes cells for apoptotic and necroptotic cell death. Based on a brief description of the biology of the TWEAK/Fn14 system and Fn14 signaling, we discuss the features of the most relevant Fn14-targeting biologicals and review the preclinical data obtained with these reagents. In particular, we address problems and limitations which became evident in the preclinical studies with Fn14-targeting biologicals and debate possibilities how they could be overcome.},
  language  = {en}
}