@article{GaritanoTrojaolaSanchoGoetzetal.2021, author = {Garitano-Trojaola, Andoni and Sancho, Ana and G{\"o}tz, Ralph and Eiring, Patrick and Walz, Susanne and Jetani, Hardikkumar and Gil-Pulido, Jesus and Da Via, Matteo Claudio and Teufel, Eva and Rhodes, Nadine and Haertle, Larissa and Arellano-Viera, Estibaliz and Tibes, Raoul and Rosenwald, Andreas and Rasche, Leo and Hudecek, Michael and Sauer, Markus and Groll, J{\"u}rgen and Einsele, Hermann and Kraus, Sabrina and Kort{\"u}m, Martin K.}, title = {Actin cytoskeleton deregulation confers midostaurin resistance in FLT3-mutant acute myeloid leukemia}, series = {Communications Biology}, volume = {4}, journal = {Communications Biology}, number = {1}, doi = {10.1038/s42003-021-02215-w}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260709}, year = {2021}, abstract = {The presence of FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) is one of the most frequent mutations in acute myeloid leukemia (AML) and is associated with an unfavorable prognosis. FLT3 inhibitors, such as midostaurin, are used clinically but fail to entirely eradicate FLT3-ITD+AML. This study introduces a new perspective and highlights the impact of RAC1-dependent actin cytoskeleton remodeling on resistance to midostaurin in AML. RAC1 hyperactivation leads resistance via hyperphosphorylation of the positive regulator of actin polymerization N-WASP and antiapoptotic BCL-2. RAC1/N-WASP, through ARP2/3 complex activation, increases the number of actin filaments, cell stiffness and adhesion forces to mesenchymal stromal cells (MSCs) being identified as a biomarker of resistance. Midostaurin resistance can be overcome by a combination of midostaruin, the BCL-2 inhibitor venetoclax and the RAC1 inhibitor Eht1864 in midostaurin-resistant AML cell lines and primary samples, providing the first evidence of a potential new treatment approach to eradicate FLT3-ITD+AML. Garitano-Trojaola et al. used a combination of human acute myeloid leukemia (AML) cell lines and primary samples to show that RAC1-dependent actin cytoskeleton remodeling through BCL2 family plays a key role in resistance to the FLT3 inhibitor, Midostaurin in AML. They showed that by targeting RAC1 and BCL2, Midostaurin resistance was diminished, which potentially paves the way for an innovate treatment approach for FLT3 mutant AML.}, language = {en} } @article{LockUngeheuerBorstetal.2020, author = {Lock, J. F. and Ungeheuer, L. and Borst, P. and Swol, J. and L{\"o}b, S. and Brede, E. M. and R{\"o}der, D. and Lengenfelder, B. and Sauer, K. and Gremer, C. - T.}, title = {Markedly increased risk of postoperative bleeding complications during perioperative bridging anticoagulation in general and visceral surgery}, series = {Perioperative Medicine}, volume = {9}, journal = {Perioperative Medicine}, doi = {10.1186/s13741-020-00170-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230690}, year = {2020}, abstract = {Background Increasing numbers of patients receiving oral anticoagulants are undergoing elective surgery. Low molecular weight heparin (LMWH) is frequently applied as bridging therapy during perioperative interruption of anticoagulation. The aim of this study was to explore the postoperative bleeding risk of patients receiving surgery under bridging anticoagulation. Methods We performed a monocentric retrospective two-arm matched cohort study. Patients that received perioperative bridging anticoagulation were compared to a matched control group with identical surgical procedure, age, and sex. Emergency and vascular operations were excluded. The primary endpoint was the incidence of major postoperative bleeding. Secondary endpoints were minor postoperative bleeding, thromboembolic events, length of stay, and in-hospital mortality. Multivariate analysis explored risk factors of major postoperative bleeding. Results A total of 263 patients in each study arm were analyzed. The patient cohort included the entire field of general and visceral surgery including a large proportion of major oncological resections. Bridging anticoagulation increased the postoperative incidence of major bleeding events (8\% vs. 1\%; p < 0.001) as well as minor bleeding events (14\% vs. 5\%; p < 0.001). Thromboembolic events were equally rare in both groups (1\% vs. 2\%; p = 0.45). No effect on mortality was observed (1.5\% vs. 1.9\%). Independent risk factors of major postoperative bleeding were full-therapeutic dose of LMWH, renal insufficiency, and the procedure-specific bleeding risk. Conclusion Perioperative bridging anticoagulation, especially full-therapeutic dose LMWH, markedly increases the risk of postoperative bleeding complications in general and visceral surgery. Surgeons should carefully consider the practice of routine bridging.}, language = {en} } @article{BroschKorsaTabanetal.2022, author = {Brosch, Philippa K. and Korsa, Tessa and Taban, Danush and Eiring, Patrick and Hildebrand, Sascha and Neubauer, Julia and Zimmermann, Heiko and Sauer, Markus and Shirakashi, Ryo and Djuzenova, Cholpon S. and Sisario, Dmitri and Sukhorukov, Vladimir L.}, title = {Glucose and inositol transporters, SLC5A1 and SLC5A3, in glioblastoma cell migration}, series = {Cancers}, volume = {14}, journal = {Cancers}, number = {23}, issn = {2072-6694}, doi = {10.3390/cancers14235794}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297498}, year = {2022}, abstract = {(1) Background: The recurrence of glioblastoma multiforme (GBM) is mainly due to invasion of the surrounding brain tissue, where organic solutes, including glucose and inositol, are abundant. Invasive cell migration has been linked to the aberrant expression of transmembrane solute-linked carriers (SLC). Here, we explore the role of glucose (SLC5A1) and inositol transporters (SLC5A3) in GBM cell migration. (2) Methods: Using immunofluorescence microscopy, we visualized the subcellular localization of SLC5A1 and SLC5A3 in two highly motile human GBM cell lines. We also employed wound-healing assays to examine the effect of SLC inhibition on GBM cell migration and examined the chemotactic potential of inositol. (3) Results: While GBM cell migration was significantly increased by extracellular inositol and glucose, it was strongly impaired by SLC transporter inhibition. In the GBM cell monolayers, both SLCs were exclusively detected in the migrating cells at the monolayer edge. In single GBM cells, both transporters were primarily localized at the leading edge of the lamellipodium. Interestingly, in GBM cells migrating via blebbing, SLC5A1 and SLC5A3 were predominantly detected in nascent and mature blebs, respectively. (4) Conclusion: We provide several lines of evidence for the involvement of SLC5A1 and SLC5A3 in GBM cell migration, thereby complementing the migration-associated transportome. Our findings suggest that SLC inhibition is a promising approach to GBM treatment.}, language = {en} } @article{FischerHarrisonRamirezetal.2017, author = {Fischer, Annette and Harrison, Kelly S and Ramirez, Yesid and Auer, Daniela and Chowdhury, Suvagata Roy and Prusty, Bhupesh K and Sauer, Florian and Dimond, Zoe and Kisker, Caroline and Hefty, P Scott and Rudel, Thomas}, title = {Chlamydia trachomatis-containing vacuole serves as deubiquitination platform to stabilize Mcl-1 and to interfere with host defense}, series = {eLife}, volume = {6}, journal = {eLife}, number = {e21465}, doi = {10.7554/eLife.21465}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171073}, year = {2017}, abstract = {Obligate intracellular Chlamydia trachomatis replicate in a membrane-bound vacuole called inclusion, which serves as a signaling interface with the host cell. Here, we show that the chlamydial deubiquitinating enzyme (Cdu) 1 localizes in the inclusion membrane and faces the cytosol with the active deubiquitinating enzyme domain. The structure of this domain revealed high similarity to mammalian deubiquitinases with a unique α-helix close to the substrate-binding pocket. We identified the apoptosis regulator Mcl-1 as a target that interacts with Cdu1 and is stabilized by deubiquitination at the chlamydial inclusion. A chlamydial transposon insertion mutant in the Cdu1-encoding gene exhibited increased Mcl-1 and inclusion ubiquitination and reduced Mcl-1 stabilization. Additionally, inactivation of Cdu1 led to increased sensitivity of C. trachomatis for IFNγ and impaired infection in mice. Thus, the chlamydial inclusion serves as an enriched site for a deubiquitinating activity exerting a function in selective stabilization of host proteins and protection from host defense.}, language = {en} }