@article{GlutschKneitzGesierichetal.2021,
  author    = {Glutsch, Valerie and Kneitz, Hermann and Gesierich, Anja and Goebeler, Matthias and Haferkamp, Sebastian and Becker, J{\"u}rgen C. and Ugurel, Selma and Schilling, Bastian},
  title     = {Activity of ipilimumab plus nivolumab in avelumab-refractory Merkel cell carcinoma},
  series = {Cancer Immunology, Immunotherapy},
  volume    = {70},
  journal   = {Cancer Immunology, Immunotherapy},
  number    = {7},
  issn      = {14320851},
  doi       = {10.1007/s00262-020-02832-0},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265635},
  pages     = {2087-2093},
  year      = {2021},
  abstract  = {Background Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine cutaneous malignancy with poor prognosis. In Europe, approved systemic therapies are limited to the PD-L1 inhibitor avelumab. For avelumab-refractory patients, efficient and safe treatment options are lacking. Methods At three different sites in Germany, clinical and molecular data of patients with metastatic MCC being refractory to the PD-L1 inhibitor avelumab and who were later on treated with combined IPI/NIVO were retrospectively collected and evaluated. Results Five patients treated at three different academic sites in Germany were enrolled. Three out of five patients investigated for this report responded to combined IPI/NIVO according to RECIST 1.1. Combined immunotherapy was well tolerated without any grade II or III immune-related adverse events. Two out of three responders to IPI/NIVO received platinum-based chemotherapy in between avelumab and combined immunotherapy. Conclusion In this small retrospective study, we observed a high response rate and durable responses to subsequent combined immunotherapy with IPI/NIVO in avelumab-refractory metastatic MCC patients. In conclusion, our data suggest a promising activity of second- or third-line PD-1- plus CTLA-4-blockade in patients with anti-PD-L1-refractory MCC.},
  language  = {en}
}
@article{FringsGoebelerSchillingetal.2021,
  author    = {Frings, Verena Gerlinde and Goebeler, Matthias and Schilling, Bastian and Kneitz, Hermann},
  title     = {Aberrant cytoplasmic connexin43 expression as a helpful marker in vascular neoplasms},
  series = {Journal of Cutaneous Pathology},
  volume    = {48},
  journal   = {Journal of Cutaneous Pathology},
  number    = {11},
  doi       = {10.1111/cup.14066},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-258412},
  pages     = {1335-1341},
  year      = {2021},
  abstract  = {Background Gap junctions consisting of connexins (Cx) are fundamental in controlling cell proliferation, differentiation, and cell death. Cx43 is the most broadly expressed Cx in humans and is attributed an important role in skin tumor development. Its role in cutaneous vascular neoplasms is yet unknown. Methods Fifteen cases each of cutaneous angiosarcoma (cAS), Kaposi sarcoma (KS), and cherry hemangioma (CH) were assessed by immunohistochemistry for expression of Cx43. Expression pattern, intensity, and percentage of positively stained cells were analyzed. Solid basal cell carcinomas served as positive and healthy skin as negative controls. Results Most cases of cAS presented with a strong Cx43 staining of almost all tumor cells, whereas endothelia of KS showed medium expression and CH showed mostly weak expression. In comparison with KS or cAS, the staining intensity of CH was significantly lower (P ≤ 0.001). All tissue sections of both cAS and KS were characterized by a mostly diffuse, cytoplasmic staining pattern of the vascular endothelia. None of those showed nuclear staining. Conclusion The high-to-intermediate expression of Cx43 observed in all cases of cAS and KS suggests that this Cx may play a role in the development of malignant vascular neoplasms and serve as a helpful diagnostic marker.},
  language  = {en}
}
@article{HoeslFroehlichPoschetal.2021,
  author    = {Hoesl, Christine and Fr{\"o}hlich, Thomas and Posch, Christian and Kneitz, Hermann and Goebeler, Matthias and Schneider, Marlon R. and Dahlhoff, Maik},
  title     = {The transmembrane protein LRIG1 triggers melanocytic tumor development following chemically induced skin carcinogenesis},
  series = {Molecular Oncology},
  volume    = {15},
  journal   = {Molecular Oncology},
  number    = {8},
  doi       = {10.1002/1878-0261.12945},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-238925},
  pages     = {2140 -- 2155},
  year      = {2021},
  abstract  = {The incidence of melanoma and nonmelanoma skin cancer has increased tremendously in recent years. Although novel treatment options have significantly improved patient outcomes, the prognosis for most patients with an advanced disease remains dismal. It is, thus, imperative to understand the molecular mechanisms involved in skin carcinogenesis in order to develop new targeted treatment strategies. Receptor tyrosine kinases (RTK) like the ERBB receptor family, including EGFR/ERBB1, ERBB2/NEU, ERBB3, and ERBB4, are important regulators of skin homeostasis and their dysregulation often results in cancer, which makes them attractive therapeutic targets. Members of the leucine-rich repeats and immunoglobulin-like domains protein family (LRIG1-3) are ERBB regulators and thus potential therapeutic targets to manipulate ERBB receptors. Here, we analyzed the function of LRIG1 during chemically induced skin carcinogenesis in transgenic mice expressing LRIG1 in the skin under the control of the keratin 5 promoter (LRIG1-TG mice). We observed a significant induction of melanocytic tumor formation in LRIG1-TG mice and no difference in papilloma incidence between LRIG1-TG and control mice. Our findings also revealed that LRIG1 affects ERBB signaling via decreased phosphorylation of EGFR and increased activation of the oncoprotein ERBB2 during skin carcinogenesis. The epidermal proliferation rate was significantly decreased during epidermal tumorigenesis under LRIG1 overexpression, and the apoptosis marker cleaved caspase 3 was significantly activated in the epidermis of transgenic LRIG1 mice. Additionally, we detected LRIG1 expression in human cutaneous squamous cell carcinoma and melanoma samples. Therefore, we depleted LRIG1 in human melanoma cells (A375) by CRISPR/Cas9 technology and found that this caused EGFR and ERBB3 downregulation in A375 LRIG1 knockout cells 6 h following stimulation with EGF. In conclusion, our study demonstrated that LRIG1-TG mice develop melanocytic skin tumors during chemical skin carcinogenesis and a deletion of LRIG1 in human melanoma cells reduces EGFR and ERBB3 expression after EGF stimulation.},
  language  = {en}
}