TY - JOUR A1 - Hesbacher, Sonja A1 - Pfitzer, Lisa A1 - Wiedorfer, Katharina A1 - Angermeyer, Sabrina A1 - Borst, Andreas A1 - Haferkamp, Sebastian A1 - Scholz, Claus-Jürgen A1 - Wobser, Marion A1 - Schrama, David A1 - Houben, Roland T1 - RB1 is the crucial target of the Merkel cell polyomavirus Large T antigen in Merkel cell carcinoma cells JF - Oncotarget N2 - The pocket protein (PP) family consists of the three members RB1, p107 and p130 all possessing tumor suppressive properties. Indeed, the PPs jointly control the G1/S transition mainly by inhibiting E2F transcription factors. Notably, several viral oncoproteins are capable of binding and inhibiting PPs. Merkel cell polyomavirus (MCPyV) is considered as etiological factor for Merkel cell carcinoma (MCC) with expression of the viral Large T antigen (LT) harboring an intact PP binding domain being required for proliferation of most MCC cells. Therefore, we analyzed the interaction of MCPyV-LT with the PPs. Co-IP experiments indicate that MCPyV-LT binds potently only to RB1. Moreover, MCPyV-LT knockdown-induced growth arrest in MCC cells can be rescued by knockdown of RB1, but not by p107 or p130 knockdown. Accordingly, cell cycle arrest and E2F target gene repression mediated by the single PPs can only in the case of RB1 be significantly reverted by MCPyV-LT expression. Moreover, data from an MCC patient indicate that loss of RB1 rendered the MCPyV-positive MCC cells LT independent. Thus, our results suggest that RB1 is the dominant tumor suppressor PP in MCC, and that inactivation of RB1 by MCPyV-LT is largely sufficient for its growth supporting function in established MCPyV-positive MCC cells. KW - Merkel cell carcinoma KW - polyomavirus KW - Large T antigen KW - retinoblastoma protein KW - viral carcinogenesis Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177858 VL - 7 IS - 22 ER - TY - JOUR A1 - Wobser, Marion A1 - Gaigl, Zeno A1 - Trautmann, Axel T1 - The concept of "compartment allergy": prilocaine injected into different skin layers N2 - We herein present a patient with delayed-type allergic hypersensitivity against prilocaine leading to spreading eczematous dermatitis after subcutaneous injections for local anesthesia with prilocaine. Prilocaine allergy was proven by positive skin testing and subcutaneous provocation, whereas the evaluation of other local anesthetics - among them lidocaine, articaine and mepivacaine - did not exhibit any evidence for cross-reactivity. Interestingly, our patient repeatedly tolerated strictly deep subcutaneous injection of prilocaine in provocation testing while patch and superficial subcutaneous application mounted strong allergic responses. We hypothesize, that lower DC density in deeper cutaneous compartments and/or different DC subsets exhibiting distinct functional immunomodulatory properties in the various layers of the skin may confer to the observed absence of clinical reactivity against prilocaine after deep subcutaneous injection. The term compartment allergy indicates that the route of allergen administration together with the targeted immunologic environment orchestrates on the immunologic outcome: overt T-cell mediated allergy or clinical tolerance. KW - Medizin Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68679 ER - TY - JOUR A1 - Haferkamp, Sebastian A1 - Hesbacher, Sonja A1 - Weyandt, Gerhard A1 - Vetter-Kauczok, Claudia S. A1 - Becker, Jürgen C. A1 - Motschenbacher, Stephanie A1 - Wobser, Marion A1 - Maier, Melissa A1 - Schmid, Corinna P. A1 - Houben, Roland T1 - p53 regulation by TRP2 is not pervasive in melanoma N2 - p53 is a central tumor suppressor protein and its inhibition is believed to be a prerequisite for cancer development. In approximately 50% of all malignancies this is achieved by inactivating mutations in the p53 gene. However, in several cancer entities, including melanoma, p53 mutations are rare. It has been recently proposed that tyrosinase related protein 2 (TRP2), a protein involved in melanin synthesis, may act as suppressor of the p53 pathway in melanoma. To scrutinize this notion we analyzed p53 and TRP2 expression by immunohistochemistry in 172 melanoma tissues and did not find any correlation. Furthermore, we applied three different TRP2 shRNAs to five melanoma cell lines and could not observe a target specific effect of the TRP2 knockdown on either p53 expression nor p53 reporter gene activity. Likewise, ectopic expression of TRP2 in a TRP2 negative melanoma cell line had no impact on p53 expression. In conclusion our data suggest that p53 repression critically controlled by TRP2 is not a general event in melanoma. KW - melanomas KW - melanoma cell KW - cell staining KW - histology KW - reporter genes KW - apoptosis KW - immunohistochemistry techniques KW - tumor suppressor genes Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-111396 ER - TY - JOUR A1 - Becker, Jürgen C. A1 - Andersen, Mads H. A1 - Hofmeister-Müller, Valeska A1 - Wobser, Marion A1 - Frey, Lidia A1 - Sandig, Christiane A1 - Walter, Steffen A1 - Singh-Jasuja, Harpreet A1 - Kämpgen, Eckhart A1 - Opitz, Andreas A1 - Zapatka, Marc A1 - Bröcker, Eva-B. A1 - thor Straten, Per A1 - Schrama, David A1 - Ugurel, Selma T1 - Survivin-specific T-cell reactivity correlates with tumor response and patient survival: a phase-II peptide vaccination trial in metastatic melanoma JF - Cancer Immunology, Immunotherapy N2 - Background Therapeutic vaccination directed to induce an anti-tumoral T-cell response is a field of extensive investigation in the treatment of melanoma. However, many vaccination trials in melanoma failed to demonstrate a correlation between the vaccine-specific immune response and therapy outcome. This has been mainly attributed to immune escape by antigen loss, rendering us in the need of new vaccination targets. Patients and methods This phase-II trial investigated a peptide vaccination against survivin, an oncogenic inhibitor-of-apoptosis protein crucial for the survival of tumor cells, in HLA-A1/-A2/-B35-positive patients with treatment-refractory stage-IV metastatic melanoma. The study endpoints were survivin-specific T-cell reactivity (SSTR), safety, response, and survival (OS). Results Sixty-one patients (ITT) received vaccination therapy using three different regimens. 55 patients (PP) were evaluable for response and survival, and 41/55 for SSTR. Patients achieving progression arrest (CR + PR + SD) more often showed SSTRs than patients with disease progression (p = 0.0008). Patients presenting SSTRs revealed a prolonged OS (median 19.6 vs. 8.6 months; p = 0.0077); multivariate analysis demonstrated SSTR as an independent predictor of survival (p = 0.013). The induction of SSTRs was associated with gender (female vs. male; p = 0.014) and disease stage (M1a/b vs. M1c; p = 0.010), but not with patient age, HLA type, performance status, or vaccination regimen. Conclusion Survivin-specific T-cell reactivities strongly correlate with tumor response and patient survival, indicating that vaccination with survivin-derived peptides is a promising treatment strategy in melanoma. KW - peptide vaccination KW - therapy KW - survivin T-cell reactivity KW - melanoma Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126215 VL - 61 IS - 11 ER - TY - JOUR A1 - Becker, Jürgen C. A1 - Andersen, Mads H. A1 - Hofmeister-Müller, Valeska A1 - Wobser, Marion A1 - Frey, Lidia A1 - Sandig, Christiane A1 - Walter, Steffen A1 - Singh-Jasuja, Harpreet A1 - Kämpgen, Eckhart A1 - Opitz, Andreas A1 - Zapatka, Marc A1 - Bröcker, Eva-B. A1 - thor Straten, Per A1 - Schrama, David A1 - Ugurel, Selma T1 - Survivin-specific T-cell reactivity correlates with tumor response and patient survival: a phase-II peptide vaccination trial in metastatic melanoma JF - Cancer Immunology, Immunotherapy N2 - Background Therapeutic vaccination directed to induce an anti-tumoral T-cell response is a field of extensive investigation in the treatment of melanoma. However, many vaccination trials in melanoma failed to demonstrate a correlation between the vaccine-specific immune response and therapy outcome. This has been mainly attributed to immune escape by antigen loss, rendering us in the need of new vaccination targets. Patients and methods This phase-II trial investigated a peptide vaccination against survivin, an oncogenic inhibitor-of-apoptosis protein crucial for the survival of tumor cells, in HLA-A1/-A2/-B35-positive patients with treatment-refractory stage-IV metastatic melanoma. The study endpoints were survivin-specific T-cell reactivity (SSTR), safety, response, and survival (OS). Results Sixty-one patients (ITT) received vaccination therapy using three different regimens. 55 patients (PP) were evaluable for response and survival, and 41/55 for SSTR. Patients achieving progression arrest (CR + PR + SD) more often showed SSTRs than patients with disease progression (p = 0.0008). Patients presenting SSTRs revealed a prolonged OS (median 19.6 vs. 8.6 months; p = 0.0077); multivariate analysis demonstrated SSTR as an independent predictor of survival (p = 0.013). The induction of SSTRs was associated with gender (female vs. male; p = 0.014) and disease stage (M1a/b vs. M1c; p = 0.010), but not with patient age, HLA type, performance status, or vaccination regimen. Conclusion Survivin-specific T-cell reactivities strongly correlate with tumor response and patient survival, indicating that vaccination with survivin-derived peptides is a promising treatment strategy in melanoma. KW - peptide vaccination KW - melanoma KW - survivin KW - T-cell reactivity KW - therapy Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124830 VL - 61 IS - 11 ER - TY - JOUR A1 - Wobser, Marion A1 - Siedel, Claudia A1 - Kneitz, Hermann A1 - Bröcker, Eva-Bettina A1 - Goebeler, Mathias A1 - Houben, Roland A1 - Geissinger, Eva T1 - Microvessel Density and Expression of Vascular Endothelial Growth Factor and its Receptors in Different Subtypes of Primary Cutaneous B-cell Lymphoma JF - Acta Dermato-Venereologica N2 - A proangiogenic micromilieu is associated with a worse prognosis in systemic lymphoma. Hence, targeting the tumour microenvironment and its vasculature has evolved as a promising novel treatment strategy. The role of tumour neoangiogenesis in cutaneous B-cell lymphoma, however, has not yet been elucidated. Therefore, we examined the expression of vascular endothelial growth factor (VEGF) and its receptors VEGFR-1 and VEGFR-2, as well as microvessel density by immunohistochemistry in paraffin-embedded specimens of different subtypes of primary cutaneous B-cell lymphomas, systemic diffuse large B-cell lymphoma, and cutaneous B-cell pseudolymphoma. Primary cutaneous large B-cell lymphoma (PCLBCL) were characterized by significantly higher intratumoral expression levels of VEGF and its receptors in comparison with the indolent lymphoma subtypes. Moreover, PCLBCL exhibited significantly higher intratumoral microvessel counts. Our study provides evidence that the most aggressive subtype of cutaneous B-cell lymphoma, PCLBCL, is characterized by a proangiogenic micromilieu. KW - microvessel density KW - vascular endothelial growth KW - B-cell lymphoma KW - subtypes Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128608 VL - 93 IS - 6 ER - TY - JOUR A1 - Jessen, Christina A1 - Kreß, Julia K. C. A1 - Baluapuri, Apoorva A1 - Hufnagel, Anita A1 - Schmitz, Werner A1 - Kneitz, Susanne A1 - Roth, Sabine A1 - Marquardt, André A1 - Appenzeller, Silke A1 - Ade, Casten P. A1 - Glutsch, Valerie A1 - Wobser, Marion A1 - Friedmann-Angeli, José Pedro A1 - Mosteo, Laura A1 - Goding, Colin R. A1 - Schilling, Bastian A1 - Geissinger, Eva A1 - Wolf, Elmar A1 - Meierjohann, Svenja T1 - The transcription factor NRF2 enhances melanoma malignancy by blocking differentiation and inducing COX2 expression JF - Oncogene N2 - The transcription factor NRF2 is the major mediator of oxidative stress responses and is closely connected to therapy resistance in tumors harboring activating mutations in the NRF2 pathway. In melanoma, such mutations are rare, and it is unclear to what extent melanomas rely on NRF2. Here we show that NRF2 suppresses the activity of the melanocyte lineage marker MITF in melanoma, thereby reducing the expression of pigmentation markers. Intriguingly, we furthermore identified NRF2 as key regulator of immune-modulating genes, linking oxidative stress with the induction of cyclooxygenase 2 (COX2) in an ATF4-dependent manner. COX2 is critical for the secretion of prostaglandin E2 and was strongly induced by H\(_2\)O\(_2\) or TNFα only in presence of NRF2. Induction of MITF and depletion of COX2 and PGE2 were also observed in NRF2-deleted melanoma cells in vivo. Furthermore, genes corresponding to the innate immune response such as RSAD2 and IFIH1 were strongly elevated in absence of NRF2 and coincided with immune evasion parameters in human melanoma datasets. Even in vitro, NRF2 activation or prostaglandin E2 supplementation blunted the induction of the innate immune response in melanoma cells. Transcriptome analyses from lung adenocarcinomas indicate that the observed link between NRF2 and the innate immune response is not restricted to melanoma. KW - NRF2 KW - melanoma malignancy KW - COX2 expression Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235064 SN - 0950-9232 VL - 39 ER - TY - JOUR A1 - Wobser, Marion A1 - Roth, Sabine A1 - Appenzeller, Silke A1 - Houben, Roland A1 - Schrama, David A1 - Goebeler, Matthias A1 - Geissinger, Eva A1 - Rosenwald, Andreas A1 - Maurus, Katja T1 - Targeted deep sequencing of mycosis fungoides reveals intracellular signaling pathways associated with aggressiveness and large cell transformation JF - Cancers N2 - Introduction: Large-cell transformation (LCT) of mycosis fungoides (MF) has been associated with a higher risk of relapse and progression and, consequently, restricted prognosis. Its molecular pathogenesis has not been elucidated yet. Materials and Methods: In order to address molecular mechanisms of LCT, we performed hybrid capture panel-based sequencing of skin biopsies from 10 patients suffering from MF with LCT versus 17 patients without LCT including follow-up biopsies during clinical course, respectively (51 samples in total). The analyzed patients were attributed to three different groups based on the presence of LCT and clinical behavior. Results: While indolent MF cases without LCT did not show pathogenic driver mutations, a high rate of oncogenic alterations was detected in patients with LCT and aggressive clinical courses. Various genes of different oncogenic signaling pathways, including the MAPK and JAK-STAT signaling pathways, as well as epigenetic modifiers were affected. A high inter-individual and distinctive intra-individual mutation diversity was observed. Oncogenic RAS mutations were exclusively detected in patients with LCT. Conclusion: Our data demonstrate that LCT transition of MF is associated with increased frequency of somatic mutations in cancer-associated genes. In particular, the activation of RAS signaling — together with epigenetic dysregulation — may crucially contribute to the molecular pathogenesis of the LCT phenotype, thus conveying its adverse clinical behavior. KW - mycosis fungoides KW - cutaneous T-cell-lymphoma KW - panel sequencing KW - large cell transformation KW - CD30 Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-250094 SN - 2072-6694 VL - 13 IS - 21 ER - TY - JOUR A1 - Grimm, Johannes A1 - Hufnagel, Anita A1 - Wobser, Marion A1 - Borst, Andreas A1 - Haferkamp, Sebastian A1 - Houben, Roland A1 - Meierjohann, Svenja T1 - BRAF inhibition causes resilience of melanoma cell lines by inducing the secretion of FGF1 JF - Oncogenesis N2 - Approximately half of all melanoma patients harbour activating mutations in the serine/threonine kinase BRAF. This is the basis for one of the main treatment strategies for this tumor type, the targeted therapy with BRAF and MEK inhibitors. While the initial responsiveness to these drugs is high, resistance develops after several months, frequently at sites of the previously responding tumor. This indicates that tumor response is incomplete and that a certain tumor fraction survives even in drug-sensitive patients, e.g., in a therapy-induced senescence-like state. Here, we show in several melanoma cell lines that BRAF inhibition induces a secretome with stimulating effect on fibroblasts and naive melanoma cells. Several senescence-associated factors were found to be transcribed and secreted in response to BRAF or MEK inhibition, among them members of the fibroblast growth factor family. We identified the growth factor FGF1 as mediator of resilience towards BRAF inhibition, which limits the pro-apoptotic effects of the drug and activates fibroblasts to secrete HGF. FGF1 regulation was mediated by the PI3K pathway and by FRA1, a direct target gene of the MAPK pathway. When FGFR inhibitors were applied in parallel to BRAF inhibitors, resilience was broken, thus providing a rationale for combined therapeutical application. KW - melanoma KW - senescence KW - BRAF KW - tumor Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177261 VL - 7 IS - 71 ER - TY - JOUR A1 - Thomas, Anna C. A1 - Zeng, Zhiqiang A1 - Rivière, Jean-Baptiste A1 - O'Shaughnessy, Ryan A1 - Al-Olabi, Lara A1 - St.-Onge, Judith A1 - Atherton, David J. A1 - Aubert, Hélène A1 - Bagazgoitia, Lorea A1 - Barbarot, Sébastien A1 - Bourrat, Emmanuelle A1 - Chiaverini, Christine A1 - Chong, W. Kling A1 - Duffourd, Yannis A1 - Glover, Mary A1 - Groesser, Leopold A1 - Hadj-Rabia, Smail A1 - Hamm, Henning A1 - Happle, Rudolf A1 - Mushtaq, Imran A1 - Lacour, Jean-Philippe A1 - Waelchli, Regula A1 - Wobser, Marion A1 - Vabres, Pierre A1 - Patton, E. Elizabeth A1 - Kinsler, Veronica A. T1 - Mosaic activating mutations in GNA11 and GNAQ are associated with phakomatosis pigmentovascularis and extensive dermal melanocytosis JF - Journal of Investigative Dermatology N2 - Common birthmarks can be an indicator of underlying genetic disease but are often overlooked. Mongolian blue spots (dermal melanocytosis) are usually localized and transient, but they can be extensive, permanent, and associated with extracutaneous abnormalities. Co-occurrence with vascular birthmarks defines a subtype of phakomatosis pigmentovascularis, a group of syndromes associated with neurovascular, ophthalmological, overgrowth, and malignant complications. Here, we discover that extensive dermal melanocytosis and phakomatosis pigmentovascularis are associated with activating mutations in GNA11 and GNAQ, genes that encode Ga subunits of heterotrimeric G proteins. The mutations were detected at very low levels in affected tissues but were undetectable in the blood, indicating that these conditions are postzygotic mosaic disorders. In vitro expression of mutant GNA11\(^R183C\) and GNA11\(^Q209L\) in human cell lines demonstrated activation of the downstream p38 MAPK signaling pathway and the p38, JNK, and ERK pathways, respectively. Transgenic mosaic zebrafish models expressing mutant GNA11\(^R183C\) under promoter mitfa developed extensive dermal melanocytosis recapitulating the human phenotype. Phakomatosis pigmentovascularis and extensive dermal melanocytosis are therefore diagnoses in the group of mosaic heterotrimeric G-protein disorders, joining McCune-Albright and Sturge-Weber syndromes. These findings will allow accurate clinical and molecular diagnosis of this subset of common birthmarks, thereby identifying infants at risk for serious complications, and provide novel therapeutic opportunities. KW - uveal melanoma KW - G Protein KW - dermal melanocytosis KW - Sturge-Weber syndrom KW - cesioflammea KW - germline KW - phakomatosis pigmentovascularis Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189689 VL - 136 IS - 4 ER - TY - JOUR A1 - Wobser, Marion A1 - Weber, Alexandra A1 - Glunz, Amelie A1 - Tauch, Saskia A1 - Seitz, Kristina A1 - Butelmann, Tobias A1 - Hesbacher, Sonja A1 - Goebeler, Matthias A1 - Bartz, René A1 - Kohlhof, Hella A1 - Schrama, David A1 - Houben, Roland T1 - Elucidating the mechanism of action of domatinostat (4SC-202) in cutaneous T cell lymphoma cells JF - Journal of Hematology & Oncology N2 - Background Targeting epigenetic modifiers is effective in cutaneous T cell lymphoma (CTCL). However, there is a need for further improvement of this therapeutic approach. Here, we compared the mode of action of romidepsin (FK228), an established class I histone deacetylase inhibitor, and domatinostat (4SC-202), a novel inhibitor of class I HDACs, which has been reported to also target the lysine-specific histone demethylase 1A (LSD1). Methods We performed MTS assays and flow cytometric analyses of propidium iodide or annexin V-stained cells to assess drug impact on cellular proliferation, cell cycle distribution, and survival. Histone acetylation and methylation as well as caspase activation was analyzed by immunoblot. Gene expression analysis was performed using NanosString technology. Knockdown and knockout of LSD1 was achieved with shRNA and CRISPR/Cas9, respectively, while the CRISPR/Cas9 synergistic activation mediator system was used to induce expression of endogenous HDACs and LSD1. Furthermore, time-lapse fluorescence microscopy and an in vitro tubulin polymerization assay were applied. Results While FK228 as well as 4SC-202 potently induced cell death in six different CTCL cell lines, only in the case of 4SC-202 death was preceded by an accumulation of cells in the G2/M phase of the cell cycle. Surprisingly, apoptosis and accumulation of cells with double DNA content occurred already at 4SC-202 concentrations hardly affecting histone acetylation and methylation, and provoking significantly less changes in gene expression compared to biologically equivalent doses of FK228. Indeed, we provide evidence that the 4SC-202-induced G2/M arrest in CTCL cells is independent of de novo transcription. Furthermore, neither enforced expression of HDAC1 nor knockdown or knockout of LSD1 affected the 4SC-202-induced effects. Since time-lapse microscopy revealed that 4SC-202 could affect mitotic spindle formation, we performed an in vitro tubulin polymerization assay revealing that 4SC-202 can directly inhibit microtubule formation. Conclusions We demonstrate that 4SC-202, a drug currently tested in clinical trials, effectively inhibits growth of CTCL cells. The anti-cancer cell activity of 4SC-202 is however not limited to LSD1-inhibition, modulation of histone modifications, and consecutive alteration of gene expression. Indeed, the compound is also a potent microtubule-destabilizing agent. KW - Cutaneous lymphoma KW - Epigenetic regulation KW - Histone deacetylase KW - HDAC KW - Lysine-specific methylase KW - LSD1 KW - Tubulin Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200703 VL - 12 ER - TY - JOUR A1 - Frings, Verena G. A1 - Roth, Sabine A1 - Rosenwald, Andreas A1 - Goebeler, Matthias A1 - Geissinger, Eva A1 - Wobser, Marion T1 - EBER in situ hybridization in subcutaneous aluminum granulomas/lymphoid hyperplasia: A diagnostic clue to differentiate injection-associated lymphoid hyperplasia from other forms of pseudolymphomas and cutaneous lymphomas JF - Journal of Cutaneous Pathology N2 - Background Subcutaneous vaccination or desensitization may induce persistent nodules at the injection sites. Without the knowledge of prior injection, histopathological work-up may be challenging. Objective Aim of this study was to contribute to the histopathological work-up of unclear subcutaneous nodules, especially their differentiation from cutaneous lymphoma. Methods We retrospectively reviewed clinical data and histopathological slides of four patients with subcutaneous nodules, which were suspected to suffer from cutaneous T- or B-cell lymphoma. Sections of these cases and 12 negative controls were stained with hematoxylin and eosin and a standardized immunohistochemical panel of B- and T-cell markers including EBER in situ hybridization as well as electron microscopy. Results In all cases, large histiocytes with granular cytoplasm compatible with intracellular aluminum hydroxide were present. EBER in situ hybridization revealed positive staining of these granular histiocytes while staining was absent in negative controls. Limitations Post hoc completion of medical history revealed that vaccination or specific immunotherapy had been applied before at the biopsy site in only three out of four patients; one patient was lost to follow-up. Conclusion EBER in situ hybridization is an adjunctive tool to differentiate aluminum-induced granuloma/lymphoid hyperplasia from other forms of pseudolymphoma and cutaneous B- or T-cell lymphomas. KW - RNA probe KW - aluminum granuloma KW - EBER in situ hybridization KW - lymphoid hyperplasia KW - pseudolymphoma Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-258405 VL - 48 IS - 5 ER - TY - JOUR A1 - Glutsch, Valerie A1 - Wobser, Marion A1 - Schilling, Bastian A1 - Gesierich, Anja A1 - Goebeler, Matthias A1 - Kneitz, Hermann T1 - PRAME expression as helpful immunohistochemical marker in rhabdoid melanoma JF - Dermatopathology N2 - Background: Rhabdoid melanoma is a rare variant of malignant melanoma with characteristic cytomorphologic features. Due to the potential loss of conventional melanocytic markers, histopathologic diagnosis is often challenging. We hypothesize that immunostaining for PReferentially expressed Antigen in MElanoma (PRAME) might have the potential to uncover the melanocytic origin of these dedifferentiated tumors. Methods: Four cases of rhabdoid primary melanomas were assessed by immunohistochemistry for expression of PRAME and conventional melanocytic markers. Immunohistochemical expression patterns were analyzed in the rhabdoid primaries and, if available, associated metastases. Results: All four cases of rhabdoid primary melanomas showed a strong nuclear positivity for PRAME, while the expression of conventional melanocytic markers S100, MART-1, SOX-10 and HMB-45 was variable between the analyzed cases. Conclusions: In summary, we report four cases of rhabdoid primary melanoma with high to intermediate expression of PRAME despite the partial and variable loss of other melanocytic markers. Hence, PRAME might facilitate the recognition of this highly aggressive entity to avoid misdiagnosis due to histopathologic pitfalls. KW - PRAME KW - rhabdoid differentiation KW - rhabdoid melanoma KW - immunohistochemistry KW - melanocytic markers Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-284115 SN - 2296-3529 VL - 9 IS - 2 SP - 148 EP - 157 ER - TY - JOUR A1 - Wobser, Marion A1 - Goebeler, Matthias T1 - Special Issue “Cutaneous Lymphomas” JF - Cancers N2 - No abstract available KW - cutaneous lymphomas Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304180 SN - 2072-6694 VL - 15 IS - 5 ER - TY - JOUR A1 - Wobser, Marion A1 - Schummer, Patrick A1 - Appenzeller, Silke A1 - Kneitz, Hermann A1 - Roth, Sabine A1 - Goebeler, Matthias A1 - Geissinger, Eva A1 - Rosenwald, Andreas A1 - Maurus, Katja T1 - Panel sequencing of primary cutaneous B-cell lymphoma JF - Cancers N2 - Background: Primary cutaneous follicular B-cell lymphoma (PCFBCL) represents an indolent subtype of Non-Hodgkin’s lymphomas, being clinically characterized by slowly growing tumors of the skin and common cutaneous relapses, while only exhibiting a low propensity for systemic dissemination or fatal outcome. Up to now, only few studies have investigated underlying molecular alterations of PCFBCL with respect to somatic mutations. Objectives: Our aim was to gain deeper insight into the pathogenesis of PCFBCL and to delineate discriminatory molecular features of this lymphoma subtype. Methods: We performed hybridization-based panel sequencing of 40 lymphoma-associated genes of 10 cases of well-characterized PCFBCL. In addition, we included two further ambiguous cases of atypical B-cell-rich lymphoid infiltrate/B-cell lymphoma of the skin for which definite subtype attribution had not been possible by routine investigations. Results: In 10 out of 12 analyzed cases, we identified genetic alterations within 15 of the selected 40 target genes. The most frequently detected alterations in PCFBCL affected the TNFRSF14, CREBBP, STAT6 and TP53 genes. Our analysis unrevealed novel mutations of the BCL2 gene in PCFBCL. All patients exhibited an indolent clinical course. Both the included arbitrary cases of atypical B-cell-rich cutaneous infiltrates showed somatic mutations within the FAS gene. As these mutations have previously been designated as subtype-specific recurrent alterations in primary cutaneous marginal zone lymphoma (PCMZL), we finally favored the diagnosis of PCMZL in these two cases based on these molecular findings. Conclusions: To conclude, our molecular data support that PCFBCL shows distinct somatic mutations which may aid to differentiate PCFBCL from pseudo-lymphoma as well as from other indolent and aggressive cutaneous B-cell lymphomas. While the detected genetic alterations of PCFBCL did not turn out to harbor any prognostic value in our cohort, our molecular data may add adjunctive discriminatory features for diagnostic purposes on a molecular level. KW - B-cell lymphoma KW - primary cutaneous follicular B-cell lymphoma KW - targeted sequencing Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-290330 SN - 2072-6694 VL - 14 IS - 21 ER -