TY  - JOUR
A1  - Mainz, Laura
A1  - Sarhan, Mohamed A. F. E.
A1  - Roth, Sabine
A1  - Sauer, Ursula
A1  - Maurus, Katja
A1  - Hartmann, Elena M.
A1  - Seibert, Helen-Desiree
A1  - Rosenwald, Andreas
A1  - Diefenbacher, Markus E.
A1  - Rosenfeldt, Mathias T.
T1  - Autophagy blockage reduces the incidence of pancreatic ductal adenocarcinoma in the context of mutant Trp53
JF  - Frontiers in Cell and Developmental Biology
N2  - Macroautophagy (hereafter referred to as autophagy) is a homeostatic process that preserves cellular integrity. In mice, autophagy regulates pancreatic ductal adenocarcinoma (PDAC) development in a manner dependent on the status of the tumor suppressor gene Trp53. Studies published so far have investigated the impact of autophagy blockage in tumors arising from Trp53-hemizygous or -homozygous tissue. In contrast, in human PDACs the tumor suppressor gene TP53 is mutated rather than allelically lost, and TP53 mutants retain pathobiological functions that differ from complete allelic loss. In order to better represent the patient situation, we have investigated PDAC development in a well-characterized genetically engineered mouse model (GEMM) of PDAC with mutant Trp53 (Trp53\(^{R172H}\)) and deletion of the essential autophagy gene Atg7. Autophagy blockage reduced PDAC incidence but had no impact on survival time in the subset of animals that formed a tumor. In the absence of Atg7, non-tumor-bearing mice reached a similar age as animals with malignant disease. However, the architecture of autophagy-deficient, tumor-free pancreata was effaced, normal acinar tissue was largely replaced with low-grade pancreatic intraepithelial neoplasias (PanINs) and insulin expressing islet β-cells were reduced. Our data add further complexity to the interplay between Atg7 inhibition and Trp53 status in tumorigenesis.
KW  - pancreatic cancer
KW  - autophagy
KW  - p53
KW  - metastasis
KW  - ATG7
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-266005
SN  - 2296-634X
VL  - 10
ER  - 
TY  - JOUR
A1  - Prieto‐Garcia, Cristian
A1  - Hartmann, Oliver
A1  - Reissland, Michaela
A1  - Braun, Fabian
A1  - Fischer, Thomas
A1  - Walz, Susanne
A1  - Schülein‐Völk, Christina
A1  - Eilers, Ursula
A1  - Ade, Carsten P.
A1  - Calzado, Marco A.
A1  - Orian, Amir
A1  - Maric, Hans M.
A1  - Münch, Christian
A1  - Rosenfeldt, Mathias
A1  - Eilers, Martin
A1  - Diefenbacher, Markus E.
T1  - Maintaining protein stability of ∆Np63 via USP28 is required by squamous cancer cells
JF  - EMBO Molecular Medicine
N2  - The transcription factor ∆Np63 is a master regulator of epithelial cell identity and essential for the survival of squamous cell carcinoma (SCC) of lung, head and neck, oesophagus, cervix and skin. Here, we report that the deubiquitylase USP28 stabilizes ∆Np63 and maintains elevated ∆NP63 levels in SCC by counteracting its proteasome‐mediated degradation. Impaired USP28 activity, either genetically or pharmacologically, abrogates the transcriptional identity and suppresses growth and survival of human SCC cells. CRISPR/Cas9‐engineered in vivo mouse models establish that endogenous USP28 is strictly required for both induction and maintenance of lung SCC. Our data strongly suggest that targeting ∆Np63 abundance via inhibition of USP28 is a promising strategy for the treatment of SCC tumours.
KW  - ∆Np63
KW  - NOTCH
KW  - squamous cell carcinoma
KW  - 28
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218303
VL  - 12
IS  - 4
ER  -