TY  - JOUR
A1  - Götz, Rudolf
A1  - Sendtner, Michael
T1  - Cooperation of Tyrosine Kinase Receptor TrkB and Epidermal Growth Factor Receptor Signaling Enhances Migration and Dispersal of Lung Tumor Cells
JF  - PLoS ONE
N2  - TrkB mediates the effects of brain-derived neurotrophic factor (BDNF) in neuronal and nonnneuronal cells. Based on recent reports that TrkB can also be transactivated through epidermal growth-factor receptor (EGFR) signaling and thus regulates migration of early neurons, we investigated the role of TrkB in migration of lung tumor cells. Early metastasis remains a major challenge in the clinical management of non-small cell lung cancer (NSCLC). TrkB receptor signaling is associated with metastasis and poor patient prognosis in NSCLC. Expression of this receptor in A549 cells and in another adenocarcinoma cell line, NCI-H441, promoted enhanced migratory capacity in wound healing assays in the presence of the TrkB ligand BDNF. Furthermore, TrkB expression in A549 cells potentiated the stimulatory effect of EGF in wound healing and in Boyden chamber migration experiments. Consistent with a potential loss of cell polarity upon TrkB expression, cell dispersal and de-clustering was induced in A549 cells independently of exogeneous BDNF. Morphological transformation involved extensive cytoskeletal changes, reduced E-cadherin expression and suppression of E-cadherin expression on the cell surface in TrkB expressing tumor cells. This function depended on MEK and Akt kinase activity but was independent of Src. These data indicate that TrkB expression in lung adenoma cells is an early step in tumor cell dissemination, and thus could represent a target for therapy development.
KW  - metastasis
KW  - neurons
KW  - non-small cell lung cancer
KW  - neuron migration
KW  - adenocarcinoma of the lung
KW  - vector cloning
KW  - lung and intrathoracic tumors
KW  - secondary lung tumors
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-119578
SN  - 1932-6203
VL  - 9
IS  - 6
ER  - 
TY  - JOUR
A1  - Pfeiffer, Verena
A1  - Götz, Rudolf
A1  - Xiang, Chaomei
A1  - Camarero, Guadelupe
A1  - Braun, Attila
A1  - Zhang, Yina
A1  - Blum, Robert
A1  - Heinsen, Helmut
A1  - Nieswandt, Bernhard
A1  - Rapp, Ulf R.
T1  - Ablation of BRaf Impairs Neuronal Differentiation in the Postnatal Hippocampus and Cerebellum
JF  - PLoS ONE
N2  - This study focuses on the role of the kinase BRaf in postnatal brain development. Mice expressing truncated, non-functional BRaf in neural stem cell-derived brain tissue demonstrate alterations in the cerebellum, with decreased sizes and fuzzy borders of the glomeruli in the granule cell layer. In addition we observed reduced numbers and misplaced ectopic Purkinje cells that showed an altered structure of their dendritic arborizations in the hippocampus, while the overall cornus ammonis architecture appeared to be unchanged. In male mice lacking BRaf in the hippocampus the size of the granule cell layer was normal at postnatal day 12 (P12) but diminished at P21, as compared to control littermates. This defect was caused by a reduced ability of dentate gyrus progenitor cells to differentiate into NeuN positive granule cell neurons. In vitro cell culture of P0/P1 hippocampal cells revealed that BRaf deficient cells were impaired in their ability to form microtubule-associated protein 2 positive neurons. Together with the alterations in behaviour, such as autoaggression and loss of balance fitness, these observations indicate that in the absence of BRaf all neuronal cellular structures develop, but neuronal circuits in the cerebellum and hippocampus are partially disturbed besides impaired neuronal generation in both structures.
KW  - granule cells
KW  - hippocampus
KW  - neurons
KW  - neuronal dendrites
KW  - embryos
KW  - dentate gyrus
KW  - neuronal differentiation
KW  - cerebellum
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130304
VL  - 8
IS  - 3
ER  -