TY  - JOUR
A1  - Prieto-Garcia, Cristian
A1  - Tomašković, Ines
A1  - Shah, Varun Jayeshkumar
A1  - Dikic, Ivan
A1  - Diefenbacher, Markus
T1  - USP28: oncogene or tumor suppressor? a unifying paradigm for squamous cell carcinoma
JF  - Cells
N2  - Squamous cell carcinomas are therapeutically challenging tumor entities. Low response rates to radiotherapy and chemotherapy are commonly observed in squamous patients and, accordingly, the mortality rate is relatively high compared to other tumor entities. Recently, targeting USP28 has been emerged as a potential alternative to improve the therapeutic response and clinical outcomes of squamous patients. USP28 is a catalytically active deubiquitinase that governs a plethora of biological processes, including cellular proliferation, DNA damage repair, apoptosis and oncogenesis. In squamous cell carcinoma, USP28 is strongly expressed and stabilizes the essential squamous transcription factor ΔNp63, together with important oncogenic factors, such as NOTCH1, c-MYC and c-JUN. It is presumed that USP28 is an oncoprotein; however, recent data suggest that the deubiquitinase also has an antineoplastic effect regulating important tumor suppressor proteins, such as p53 and CHK2. In this review, we discuss: (1) The emerging role of USP28 in cancer. (2) The complexity and mutational landscape of squamous tumors. (3) The genetic alterations and cellular pathways that determine the function of USP28 in squamous cancer. (4) The development and current state of novel USP28 inhibitors.
KW  - USP28
KW  - SCC
KW  - USP25
KW  - FBXW7
KW  - Tp63
KW  - c-MYC
KW  - ΔNp63
KW  - p53
KW  - cancer
KW  - DUB inhibitor
KW  - squamous
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-248409
SN  - 2073-4409
VL  - 10
IS  - 10
ER  - 
TY  - JOUR
A1  - Meir, Michael
A1  - Kannapin, Felix
A1  - Diefenbacher, Markus
A1  - Ghoreishi, Yalda
A1  - Kollmann, Catherine
A1  - Flemming, Sven
A1  - Germer, Christoph-Thomas
A1  - Waschke, Jens
A1  - Leven, Patrick
A1  - Schneider, Reiner
A1  - Wehner, Sven
A1  - Burkard, Natalie
A1  - Schlegel, Nicolas
T1  - Intestinal epithelial barrier maturation by enteric glial cells is GDNF-dependent
JF  - International Journal of Molecular Sciences
N2  - Enteric glial cells (EGCs) of the enteric nervous system are critically involved in the maintenance of intestinal epithelial barrier function (IEB). The underlying mechanisms remain undefined. Glial cell line-derived neurotrophic factor (GDNF) contributes to IEB maturation and may therefore be the predominant mediator of this process by EGCs. Using GFAP\(^{cre}\) x Ai14\(^{floxed}\) mice to isolate EGCs by Fluorescence-activated cell sorting (FACS), we confirmed that they synthesize GDNF in vivo as well as in primary cultures demonstrating that EGCs are a rich source of GDNF in vivo and in vitro. Co-culture of EGCs with Caco2 cells resulted in IEB maturation which was abrogated when GDNF was either depleted from EGC supernatants, or knocked down in EGCs or when the GDNF receptor RET was blocked. Further, TNFα-induced loss of IEB function in Caco2 cells and in organoids was attenuated by EGC supernatants or by recombinant GDNF. These barrier-protective effects were blunted when using supernatants from GDNF-deficient EGCs or by RET receptor blockade. Together, our data show that EGCs produce GDNF to maintain IEB function in vitro through the RET receptor.
KW  - enteric glial cells
KW  - neurotrophic factors
KW  - intestinal epithelial barrier
KW  - GDNF5
KW  - RET6
KW  - inflammatory bowel disease
KW  - enteric nervous system
KW  - gut barrier
KW  - intercellular junctions
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-258913
SN  - 1422-0067
VL  - 22
IS  - 4
ER  -