TY  - JOUR
A1  - Janzen, Dieter
A1  - Bakirci, Ezgi
A1  - Wieland, Annalena
A1  - Martin, Corinna
A1  - Dalton, Paul D.
A1  - Villmann, Carmen
T1  - Cortical Neurons form a Functional Neuronal Network in a 3D Printed Reinforced Matrix
JF  - Advanced Healthcare Materials
N2  - Impairments in neuronal circuits underly multiple neurodevelopmental and neurodegenerative disorders. 3D cell culture models enhance the complexity of in vitro systems and provide a microenvironment closer to the native situation than with 2D cultures. Such novel model systems will allow the assessment of neuronal network formation and their dysfunction under disease conditions. Here, mouse cortical neurons are cultured from embryonic day E17 within in a fiber‐reinforced matrix. A soft Matrigel with a shear modulus of 31 ± 5.6 Pa is reinforced with scaffolds created by melt electrowriting, improving its mechanical properties and facilitating the handling. Cortical neurons display enhance cell viability and the neuronal network maturation in 3D, estimated by staining of dendrites and synapses over 21 days in vitro, is faster in 3D compared to 2D cultures. Using functional readouts with electrophysiological recordings, different firing patterns of action potentials are observed, which are absent in the presence of the sodium channel blocker, tetrodotoxin. Voltage‐gated sodium currents display a current–voltage relationship with a maximum peak current at −25 mV. With its high customizability in terms of scaffold reinforcement and soft matrix formulation, this approach represents a new tool to study neuronal networks in 3D under normal and, potentially, disease conditions.
KW  - 3D electrophysiology
KW  - 3D neuronal networks
KW  - cortical neurons
KW  - melt electrowriting
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-215400
VL  - 9
IS  - 9
ER  - 
TY  - JOUR
A1  - Wieland, Annalena
A1  - Strissel, Pamela L.
A1  - Schorle, Hannah
A1  - Bakirci, Ezgi
A1  - Janzen, Dieter
A1  - Beckmann, Matthias W.
A1  - Eckstein, Markus
A1  - Dalton, Paul D.
A1  - Strick, Reiner
T1  - Brain and breast cancer cells with PTEN loss of function reveal enhanced durotaxis and RHOB dependent amoeboid migration utilizing 3D scaffolds and aligned microfiber tracts
JF  - Cancers
N2  - Background: Glioblastoma multiforme (GBM) and metastatic triple-negative breast cancer (TNBC) with PTEN mutations often lead to brain dissemination with poor patient outcome, thus new therapeutic targets are needed. To understand signaling, controlling the dynamics and mechanics of brain tumor cell migration, we implemented GBM and TNBC cell lines and designed 3D aligned microfibers and scaffolds mimicking brain structures. Methods: 3D microfibers and scaffolds were printed using melt electrowriting. GBM and TNBC cell lines with opposing PTEN genotypes were analyzed with RHO-ROCK-PTEN inhibitors and PTEN rescue using live-cell imaging. RNA-sequencing and qPCR of tumor cells in 3D with microfibers were performed, while scanning electron microscopy and confocal microscopy addressed cell morphology. Results: In contrast to the PTEN wildtype, GBM and TNBC cells with PTEN loss of function yielded enhanced durotaxis, topotaxis, adhesion, amoeboid migration on 3D microfibers and significant high RHOB expression. Functional studies concerning RHOB-ROCK-PTEN signaling confirmed the essential role for the above cellular processes. Conclusions: This study demonstrates a significant role of the PTEN genotype and RHOB expression for durotaxis, adhesion and migration dependent on 3D. GBM and TNBC cells with PTEN loss of function have an affinity for stiff brain structures promoting metastasis. 3D microfibers represent an important tool to model brain metastasizing tumor cells, where RHO-inhibitors could play an essential role for improved therapy.
KW  - 3D tumor model
KW  - 3D microfiber
KW  - amoeboid cell migration
KW  - brain cancer
KW  - breast cancer
KW  - PTEN
KW  - RHO
KW  - ROCK
KW  - durotaxis
KW  - topotaxis
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-248443
SN  - 2072-6694
VL  - 13
IS  - 20
ER  -