TY  - JOUR
A1  - Kosnopfel, Corinna
A1  - Sinnberg, Tobias
A1  - Sauer, Birgit
A1  - Niessner, Heike
A1  - Muenchow, Alina
A1  - Fehrenbacher, Birgit
A1  - Schaller, Martin
A1  - Mertens, Peter R.
A1  - Garbe, Claus
A1  - Thakur, Basant Kumar
A1  - Schittek, Birgit
T1  - Tumour progression stage-dependent secretion of YB-1 stimulates melanoma cell migration and invasion
JF  - Cancers
N2  - Secreted factors play an important role in intercellular communication. Therefore, they are not only indispensable for the regulation of various physiological processes but can also decisively advance the development and progression of tumours. In the context of inflammatory disease, Y-box binding protein 1 (YB-1) is actively secreted and the extracellular protein promotes cell proliferation and migration. In malignant melanoma, intracellular YB-1 expression increases during melanoma progression and represents an unfavourable prognostic marker. Here, we show active secretion of YB-1 from melanoma cells as opposed to benign cells of the skin. Intriguingly, YB-1 secretion correlates with the stage of melanoma progression and depends on a calcium- and ATP-dependent non-classical secretory pathway leading to the occurrence of YB-1 in the extracellular space as a free protein. Along with an elevated YB-1 secretion of melanoma cells in the metastatic growth phase, extracellular YB-1 exerts a stimulating effect on melanoma cell migration, invasion, and tumourigenicity. Collectively, these data suggest that secreted YB-1 plays a functional role in melanoma cell biology, stimulating metastasis, and may serve as a novel biomarker in malignant melanoma that reflects tumour aggressiveness.
KW  - melanoma
KW  - secretion
KW  - Y-box binding protein 1
KW  - migration and invasiveness
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-211206
SN  - 2072-6694
VL  - 12
IS  - 8
ER  - 
TY  - JOUR
A1  - Raselli, Tina
A1  - Hearn, Tom
A1  - Wyss, Annika
A1  - Atrott, Kirstin
A1  - Peter, Alain
A1  - Frey-Wagner, Isabelle
A1  - Spalinger, Marianne R.
A1  - Maggio, Ewerton M.
A1  - Sailer, Andreas W.
A1  - Schmitt, Johannes
A1  - Schreiner, Philipp
A1  - Moncsek, Anja
A1  - Mertens, Joachim
A1  - Scharl, Michael
A1  - Griffiths, William J.
A1  - Bueter, Marco
A1  - Geier, Andreas
A1  - Rogler, Gerhard
A1  - Wang, Yuqin
A1  - Misselwitz, Benjamin
T1  - Elevated oxysterol levels in human and mouse livers reflect nonalcoholic steatohepatitis
JF  - Journal of Lipid Research
N2  - Nonalcoholic steatohepatitis (NASH), a primary cause of liver disease, leads to complications such as fibrosis, cirrhosis, and carcinoma, but the pathophysiology of NASH is incompletely understood. Epstein-Barr virus-induced G protein-coupled receptor 2 (EBI2) and its oxysterol ligand 7 alpha,25-dihydroxycholesterol (7 alpha,25-diHC) are recently discovered immune regulators. Several lines of evidence suggest a role of oxysterols in NASH pathogenesis, but rigorous testing has not been performed. We measured oxysterol levels in the livers of NASH patients by LC-MS and tested the role of the EBI2-7 alpha,25-diHC system in a murine feeding model of NASH. Free oxysterol profiling in livers from NASH patients revealed a pronounced increase in 24- and 7-hydroxylated oxysterols in NASH compared with controls. Levels of 24- and 7-hydroxylated oxysterols correlated with histological NASH activity. Histological analysis of murine liver samples demonstrated ballooning and liver inflammation. No significant genotype-related differences were observed in Ebi2(-/-) mice and mice with defects in the 7 alpha,25-diHC synthesizing enzymes CH25H and CYP7B1 compared with wild-type littermate controls, arguing against an essential role of these genes in NASH pathogenesis. Elevated 24- and 7-hydroxylated oxysterol levels were confirmed in murine NASH liver samples. Our results suggest increased bile acid synthesis in NASH samples, as judged by the enhanced level of 7 alpha-hydroxycholest-4-en-3-one and impaired 24S-hydroxycholesterol metabolism as characteristic biochemical changes in livers affected by NASH.
KW  - nonalcoholic fatty liver disease
KW  - Epstein-Barr virus-induced gene 2
KW  - cholesterol 25 hydroxylase
KW  - 25-hydroxycholesterol 7 alpha-hydroxylase
KW  - mouse feeding model
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225004
VL  - 60
IS  - 7
ER  -