@article{MaurusKosnopfelKneitzetal.2022, author = {Maurus, K. and Kosnopfel, C. and Kneitz, H. and Appenzeller, S. and Schrama, D. and Glutsch, V. and Roth, S. and Gerhard-Hartmann, E. and Rosenfeldt, M. and M{\"o}hrmann, L. and Fr{\"o}hlich, M. and H{\"u}bschmann, D. and Stenzinger, A. and Glimm, H. and Fr{\"o}hling, S. and Goebeler, M. and Rosenwald, A. and Kutzner, H. and Schilling, B.}, title = {Cutaneous epithelioid haemangiomas show somatic mutations in the mitogen-activated protein kinase pathway}, series = {British Journal of Dermatology}, volume = {186}, journal = {British Journal of Dermatology}, number = {3}, doi = {10.1111/bjd.20869}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-258333}, pages = {553-563}, year = {2022}, abstract = {Background Epithelioid haemangioma (EH) arising from the skin is a benign vascular tumour with marked inflammatory cell infiltration, which exhibits a high tendency to persist and frequently recurs after resection. So far, the underlying pathogenesis is largely elusive. Objectives To identify genetic alterations by next-generation sequencing and/or droplet digital polymerase chain reaction (ddPCR) in cutaneous EH. Methods DNA and RNA from an EH lesion of an index patient were subjected to whole-genome and RNA sequencing. Multiplex PCR-based panel sequencing of genomic DNA isolated from archival formalin-fixed paraffin-embedded tissue of 18 patients with cutaneous EH was performed. ddPCR was used to confirm mutations. Results We identified somatic mutations in genes of the mitogen-activated protein kinase (MAPK) pathway (MAP2K1 and KRAS) in cutaneous EH biopsies. By ddPCR we could confirm the recurrent presence of activating, low-frequency mutations affecting MAP2K1. In total, nine out of 18 patients analysed showed activating MAPK pathway mutations, which were mutually exclusive. Comparative analysis of tissue areas enriched for lymphatic infiltrate or aberrant endothelial cells, respectively, revealed an association of these mutations with the presence of endothelial cells. Conclusions Taken together, our data suggest that EH shows somatic mutations in genes of the MAPK pathway which might contribute to the formation of this benign tumour.}, language = {en} } @article{MainzSarhanRothetal.2022, author = {Mainz, Laura and Sarhan, Mohamed A. F. E. and Roth, Sabine and Sauer, Ursula and Maurus, Katja and Hartmann, Elena M. and Seibert, Helen-Desiree and Rosenwald, Andreas and Diefenbacher, Markus E. and Rosenfeldt, Mathias T.}, title = {Autophagy blockage reduces the incidence of pancreatic ductal adenocarcinoma in the context of mutant Trp53}, series = {Frontiers in Cell and Developmental Biology}, volume = {10}, journal = {Frontiers in Cell and Developmental Biology}, issn = {2296-634X}, doi = {10.3389/fcell.2022.785252}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-266005}, year = {2022}, abstract = {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.}, language = {en} }