@article{DjuzenovaFiedlerMemmeletal.2019, author = {Djuzenova, Cholpon S. and Fiedler, Vanessa and Memmel, Simon and Katzer, Astrid and Sisario, Dmitri and Brosch, Philippa K. and G{\"o}hrung, Alexander and Frister, Svenja and Zimmermann, Heiko and Flentje, Michael and Sukhorukov, Vladimir L.}, title = {Differential effects of the Akt inhibitor MK-2206 on migration and radiation sensitivity of glioblastoma cells}, series = {BMC Cancer}, volume = {19}, journal = {BMC Cancer}, doi = {10.1186/s12885-019-5517-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200290}, pages = {299}, year = {2019}, abstract = {Background Most tumor cells show aberrantly activated Akt which leads to increased cell survival and resistance to cancer radiotherapy. Therefore, targeting Akt can be a promising strategy for radiosensitization. Here, we explore the impact of the Akt inhibitor MK-2206 alone and in combination with the dual PI3K and mTOR inhibitor PI-103 on the radiation sensitivity of glioblastoma cells. In addition, we examine migration of drug-treated cells. Methods Using single-cell tracking and wound healing migration tests, colony-forming assay, Western blotting, flow cytometry and electrorotation we examined the effects of MK-2206 and PI-103 and/or irradiation on the migration, radiation sensitivity, expression of several marker proteins, DNA damage, cell cycle progression and the plasma membrane properties in two glioblastoma (DK-MG and SNB19) cell lines, previously shown to differ markedly in their migratory behavior and response to PI3K/mTOR inhibition. Results We found that MK-2206 strongly reduces the migration of DK-MG but only moderately reduces the migration of SNB19 cells. Surprisingly, MK-2206 did not cause radiosensitization, but even increased colony-forming ability after irradiation. Moreover, MK-2206 did not enhance the radiosensitizing effect of PI-103. The results appear to contradict the strong depletion of p-Akt in MK-2206-treated cells. Possible reasons for the radioresistance of MK-2206-treated cells could be unaltered or in case of SNB19 cells even increased levels of p-mTOR and p-S6, as compared to the reduced expression of these proteins in PI-103-treated samples. We also found that MK-2206 did not enhance IR-induced DNA damage, neither did it cause cell cycle distortion, nor apoptosis nor excessive autophagy. Conclusions Our study provides proof that MK-2206 can effectively inhibit the expression of Akt in two glioblastoma cell lines. However, due to an aberrant activation of mTOR in response to Akt inhibition in PTEN mutated cells, the therapeutic window needs to be carefully defined, or a combination of Akt and mTOR inhibitors should be considered.}, language = {en} } @article{MemmelSisarioZoelleretal.2017, author = {Memmel, Simon and Sisario, Dmitri and Z{\"o}ller, Caren and Fiedler, Vanessa and Katzer, Astrid and Heiden, Robin and Becker, Nicholas and Eing, Lorenz and Ferreira, F{\´a}bio L.R. and Zimmermann, Heiko and Sauer, Markus and Flentje, Michael and Sukhorukov, Vladimir L. and Djuzenova, Cholpon S.}, title = {Migration pattern, actin cytoskeleton organization and response to PI3K-, mTOR-, and Hsp90-inhibition of glioblastoma cells with different invasive capacities}, series = {Oncotarget}, volume = {8}, journal = {Oncotarget}, number = {28}, doi = {10.18632/oncotarget.16847}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170719}, pages = {45298-45310}, year = {2017}, abstract = {High invasiveness and resistance to chemo- and radiotherapy of glioblastoma multiforme (GBM) make it the most lethal brain tumor. Therefore, new treatment strategies for preventing migration and invasion of GBM cells are needed. Using two different migration assays, Western blotting, conventional and super-resolution (dSTORM) fluorescence microscopy we examine the effects of the dual PI3K/mTOR-inhibitor PI-103 alone and in combination with the Hsp90 inhibitor NVP-AUY922 and/or irradiation on the migration, expression of marker proteins, focal adhesions and F-actin cytoskeleton in two GBM cell lines (DK-MG and SNB19) markedly differing in their invasive capacity. Both lines were found to be strikingly different in morphology and migration behavior. The less invasive DK-MG cells maintained a polarized morphology and migrated in a directionally persistent manner, whereas the highly invasive SNB19 cells showed a multipolar morphology and migrated randomly. Interestingly, a single dose of 2 Gy accelerated wound closure in both cell lines without affecting their migration measured by single-cell tracking. PI-103 inhibited migration of DK-MG (p53 wt, PTEN wt) but not of SNB19 (p53 mut, PTEN mut) cells probably due to aberrant reactivation of the PI3K pathway in SNB19 cells treated with PI-103. In contrast, NVP-AUY922 exerted strong anti-migratory effects in both cell lines. Inhibition of cell migration was associated with massive morphological changes and reorganization of the actin cytoskeleton. Our results showed a cell line-specific response to PI3K/mTOR inhibition in terms of GBM cell motility. We conclude that anti-migratory agents warrant further preclinical investigation as potential therapeutics for treatment of GBM.}, language = {en} } @article{FathyOkabeOthmanetal.2020, author = {Fathy, Moustafa and Okabe, Motonori and Othman, Eman M. and Saad Eldien, Heba M. and Yoshida, Toshiko}, title = {Preconditioning of adipose-derived mesenchymal stem-like cells with eugenol potentiates their migration and proliferation in vitro and therapeutic abilities in rat hepatic fibrosis}, series = {Molecules}, volume = {25}, journal = {Molecules}, number = {9}, issn = {1420-3049}, doi = {10.3390/molecules25092020}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-203662}, year = {2020}, abstract = {Mesenchymal stem cells (MSCs) have considerable therapeutic abilities in various disorders, including hepatic fibrosis. They may be affected with different culture conditions. This study investigated, on molecular basics, the effect of pretreatment with eugenol on the characteristics of adipose tissue-derived MSCs (ASCs) in vitro and the implication of eugenol preconditioning on the in vivo therapeutic abilities of ASCs against CCl\(_4\)-induced hepatic fibrosis in rats. The effect of eugenol on ASCs was assessed using viability, scratch migration and sphere formation assays. Expressions of genes and proteins were estimated by immunofluorescence or qRT-PCR. For the in vivo investigations, rats were divided into four groups: the normal control group, fibrotic (CCl\(_4\)) group, CCl\(_4\)+ASCs group and CCl\(_4\) + eugenol-preconditioned ASCs (CCl\(_4\)+E-ASCs) group. Eugenol affected the viability of ASCs in a concentration- and time-dependent manner. Eugenol improved their self-renewal, proliferation and migration abilities and significantly increased their expression of c-Met, reduced expression 1 (Rex1), octamer-binding transcription factor 4 (Oct4) and nanog genes. Furthermore, E-ASCs showed more of a homing ability than ASCs and improved the serum levels of ALT, AST, albumin, total bilirubin and hyaluronic acid more efficient than ASCs in treating CCl\(_4\)-induced hepatic fibrosis, which was confirmed with histopathology. More interestingly, compared to the CCl\(_4\)+ASCs group, CCl\(_4\)+E-ASCs group showed a lower expression of inducible nitric oxide synthase (iNOS), monocyte chemoattractant protein-1 (MCP-1), cluster of differentiation 163 (CD163) and tumor necrosis factor-α (TNF-α) genes and higher expression of matrix metalloproteinase (MMP)-9 and MMP-13 genes. This study, for the first time, revealed that eugenol significantly improved the self-renewal, migration and proliferation characteristics of ASCs, in vitro. In addition, we demonstrated that eugenol-preconditioning significantly enhanced the therapeutic abilities of the injected ASCs against CCl\(_4\)-induced hepatic fibrosis.}, language = {en} } @article{NguyenBeetzMerlinetal.2022, author = {Nguyen, Tu Anh Thi and Beetz, M. Jerome and Merlin, Christine and Pfeiffer, Keram and el Jundi, Basil}, title = {Weighting of celestial and terrestrial cues in the monarch butterfly central complex}, series = {Frontiers in Neural Circuits}, volume = {16}, journal = {Frontiers in Neural Circuits}, issn = {1662-5110}, doi = {10.3389/fncir.2022.862279}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-279445}, year = {2022}, abstract = {Monarch butterflies rely on external cues for orientation during their annual long-distance migration from Northern US and Canada to Central Mexico. These external cues can be celestial cues, such as the sun or polarized light, which are processed in a brain region termed the central complex (CX). Previous research typically focused on how individual simulated celestial cues are encoded in the butterfly's CX. However, in nature, the butterflies perceive several celestial cues at the same time and need to integrate them to effectively use the compound of all cues for orientation. In addition, a recent behavioral study revealed that monarch butterflies can rely on terrestrial cues, such as the panoramic skyline, for orientation and use them in combination with the sun to maintain a directed flight course. How the CX encodes a combination of celestial and terrestrial cues and how they are weighted in the butterfly's CX is still unknown. Here, we examined how input neurons of the CX, termed TL neurons, combine celestial and terrestrial information. While recording intracellularly from the neurons, we presented a sun stimulus and polarized light to the butterflies as well as a simulated sun and a panoramic scene simultaneously. Our results show that celestial cues are integrated linearly in these cells, while the combination of the sun and a panoramic skyline did not always follow a linear integration of action potential rates. Interestingly, while the sun and polarized light were invariantly weighted between individual neurons, the sun stimulus and panoramic skyline were dynamically weighted when both stimuli were simultaneously presented. Taken together, this dynamic weighting between celestial and terrestrial cues may allow the butterflies to flexibly set their cue preference during navigation.}, language = {en} }