12509
2012
eng
2239-2249
12
61
article
1
2016-01-25
--
--
Cellular and cytokine-dependent immunosuppressive mechanisms of grm1-transgenic murine melanoma
Grm1-transgenic mice spontaneously develop cutaneous melanoma. This model allowed us to scrutinize the generic immune responses over the course of melanoma development. To this end, lymphocytes obtained from spleens, unrelated lymph nodes and tumor-draining lymph nodes of mice with no evidence of disease, and low or high tumor burden were analyzed ex vivo and in vitro. Thereby, we could demonstrate an increase in the number of activated CD4\(^+\) and CD8+ lymphocytes in the respective organs with increasing tumor burden. However, mainly CD4\(^+\) T cells, which could constitute both T helper as well as immunosuppressive regulatory T cells, but not CD8\(^+\) T cells, expressed activation markers upon in vitro stimulation when obtained from tumor-bearing mice. Interestingly, these cells from tumor-burdened animals were also functionally hampered in their proliferative response even when subjected to strong in vitro stimulation. Further analyses revealed that the increased frequency of regulatory T cells in tumor-bearing mice is an early event present in all lymphoid organs. Additionally, expression of the immunosuppressive cytokines TGF-β1 and IL-10 became more evident with increased tumor burden. Notably, TGF-β1 is strongly expressed in both the tumor and the tumor-draining lymph node, whereas IL-10 expression is more pronounced in the lymph node, suggesting a more complex regulation of IL-10. Thus, similar to the situation in melanoma patients, both cytokines as well as cellular immune escape mechanisms seem to contribute to the observed immunosuppressed state of tumor-bearing grm1-transgenic mice, suggesting that this model is suitable for preclinical testing of immunomodulatory therapeutics.
Cancer Immunology, Immunotherapy
10.1007/s00262-012-1290-9
urn:nbn:de:bvb:20-opus-125096
Cancer Immunology Immunotherapy (2012) 61:2239–2249 DOI 10.1007/s00262-012-1290-9
Miriam Alb
Christopher Sie
Christian Adam
Suzie Chen
Jürgen C. Becker
David Schrama
eng
uncontrolled
regulatory T cell
eng
uncontrolled
melanoma
eng
uncontrolled
immune suppression
eng
uncontrolled
tumor-draining lymph node
Krankheiten
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/12509/Alb_2Fs00262-012-1290-9.pdf
5824
2012
eng
doctoralthesis
1
2012-05-03
--
2012-04-11
In vivo characterization of genetic factors involved in Xmrk driven melanoma formation in Medaka (Oryzias latipes): a closer look at braf, Stat5 and c-myc
In vivo Charakterisierung genetischer Faktoren mit Einfluss auf Xmrk induzierte Melanome in Medaka (Oryzias latipes): Untersuchung von braf, Stat5 und c-myc.
Melanoma arises from the malignant transformation of melanocytes and is one of the most aggressive forms of human cancer. In fish of the genus Xiphophorus, melanoma development, although very rarely, happens spontaneously in nature and can be induced by interspecific crossing. The oncogenic receptor tyrosine kinase, Xmrk, is responsible for melanoma formation in these fishes. Since Xiphophorus are live-bearing fishes and therefore not compatible with embryonic manipulation and transgenesis, the Xmrk melanoma model was brought to the medaka (Oryzias latipes) system. Xmrk expression under the control of the pigment cell specific mitf promoter leads to melanoma formation with 100% penetrance in medaka. Xmrk is an orthologue of the human epidermal growth factor receptor (EGFR) and activates several downstream signaling pathways. Examples of these pathways are the direct phosphorylation of BRAF and Stat5, as well as the enhanced transcription of C-myc. BRAF is a serine-threonine kinase which is found mutated at high frequencies in malignant melanomas. Stat5 is a transcription factor known to be constitutively activated in fish melanoma. C-myc is a transcription factor that is thought to regulate the expression of approximately 15% of all human genes and is involved in cancer progression of a large number of different tumors. To gain new in vivo information on candidate factors known to be involved in melanoma progression, I identified and analysed BRAF, Stat5 and C-myc in the laboratory fish model system medaka. BRAF protein motifs are highly conserved among vertebrates and the results of this work indicate that its function in the MAPK signaling is maintained in medaka. Transgenic medaka lines carrying a constitutive active version of BRAF (V614E) showed more pigmented skin when compared to wild type. Also, some transiently expressing BRAF V614E fishes showed a disrupted eye phenotype. In addition, I was able to identify two Stat5 copies in medaka, named Stat5ab/a and Stat5ab/b. Sequence analysis revealed a higher similarity between both Stat5 sequences when compared to either human Stat5a or Stat5b. This suggests that the two Stat5 copies in medaka arose by an independent duplication processes. I cloned these two Stat5 present in medaka, produced constitutive active and dominant negative gene versions and successfully established transgenic lines carrying each version under the control of the MITF promoter. These lines will help to elucidate questions that are still remaining in Stat5 biology and its function in melanoma progression, like the role of Stat5 phosphorylation on tumor invasiveness. In a third project during my PhD work, I analysed medaka C-myc function and indentified two copies of this gene in medaka, named c-myc17 and c-myc20, according to the chromosome where they are located. I produced conditional transgenic medaka lines carrying the c-myc17 gene coupled to the hormone binding domain of the estrogen receptor to enable specific transgene activation at a given time point. Comparable to human C-myc, medaka C-myc17 is able to induce proliferation and apoptosis in vivo after induction. Besides that, C-myc17 long-term activation led to liver hyperplasia. In summary, the medaka models generated in this work will be important to bring new in vivo information on genes involved in cancer development. Also, the generated transgenic lines can be easily crossed to the melanoma developing Xmrk medaka lines, thereby opening up the possibility to investigate their function in melanoma progression. Besides that, the generated medaka fishes make it possible to follow the whole development of melanocytes, since the embryos are transparent and can be used for high throughput chemical screens.
Melanome entstehen durch die krankhafte Transformation von Melanozyten und sind eine der aggressivsten Krebsarten beim Menschen. In Fischen der Gattung Xiphophorus können, wenn auch sehr selten, spontan Melanome entstehen oder durch spezielle Artenkreuzungen induziert werden. Grundlage für das Entstehen der Melanome in diesen Fischen ist die Rezeptortyrosinkinase Xmrk. Da alle Xiphophorus-Arten lebendgebärend sind und keine Manipulationen an Embryonen vorgenommen werden können, wurde ein Xmrk Melanommodel für Medaka (Oryzias latipes) etabliert. Die Expression von Xmrk in Pigmentzellen dieser Fischart resultiert mit 100%iger Penetranz in Melanomen. Das Xmrk ist ein Ortholog des menschlichen „epidermal growth factor“ (EGFR) und aktiviert verschiedene nachgeschaltete Signalwege. Beispiele für diese Aktivierungen sind die Phosphorylierung von BRAF, Stat5 und die erhöhte Expression von c-myc. BRAF ist eine Serin-Threoninkinase, welche oft in malignen Melanomen mutiert ist. Stat5 ist ein Transkriptionsfaktor, welcher dauerhaft in Fischtumoren aktiviert ist. C-myc ist ein Transkriptionsfaktor, welcher etwa 15% aller menschlichen Gene sowie die Entstehung vieler menschlicher Tumore reguliert. Um neue Einsichten in die Funktion der Kanidatengene im Prozess der Melanomentstehung in vivo zu erlangen, habe ich Orthologe von BRAF, Stat5 und C-myc bei Medaka identifiziert und analysiert. Die Domänen des BRAF Proteins sind hoch konserviert in allen Vertebraten. Weiterhin deuten die Ergebnisse meiner Arbeit auf eine Beibehaltung der Funktionen im MAPK Signalweg hin. Transgene Medakalinien, welche eine dauerhaft aktive Version des BRAF Gens (V614E) exprimieren, weisen einerseits eine stärkere Hautpigmentierung auf. Weiterhin treten in diesen Fischen Veränderungen der Augen auf. In einem weiteren Projekt meiner Arbeit gelang es mir, zwei Kopien des Stat5 Gens im Medaka zu identifizieren, Stat5ab/a und Stat5ab/b. Sequenzanalysen zeigten eine höhere Übereinstimmung zwischen den beiden Genkopien, als zwischen denen von Medaka und Menschen. Dieses Ergebnis deutet darauf hin, dass die beiden Medaka Gene durch eine unabhängige Duplikation entstanden. In meiner Arbeit habe ich beide Gene des Medakas kloniert und jeweils eine konstitutiv aktive und eine dominant negative Version der Gene hergestellt. Weiterhin konnte ich erfolgreich für jede Genversion eine transgene Medakalinie etablieren, welche die verschiedenen Genvarianten unter der Kontrolle des pigmentzellspezifischen Promoters des mitf Gens exprimieren. Diese Linien werden in Zukunft helfen, den Einfluss von Stat5 Signalen auf den Prozess der Melanomverbreitung und dessen Invasivität zu erklären. In einem dritten Projekt meiner Doktorarbeit untersuchte ich das Vorkommen und die Funktion der C-myc Gene des Medakas. Ich konnte zwei Genkopien identifizieren, c-myc17 und c-myc20, welche auf unterschiedlichen Chromosomen lokalisiert sind. Ich konnte induzierbare, stabil transgene Linien herstellen, welche ein Fusionsprotein aus C-myc17 und der Hormonbindungsdomäne des Östrogenrezeptors von Maus exprimiert. Diese Linie ermöglichte eine induzierbare Aktivität des Transgens. Vergleichbar zum menschlichen MYC ist C-myc17 fähig, nach Aktivierung Proliferation und Apoptose in vivo auszulösen. Dauerhafte Aktivierung über einen längeren Zeitraum führt in diesen Linien zu Hyperplasie in Leber. Die verschiedenen Fischmodelle, die während dieser Arbeit generiert wurden, werden essentiell sein, um neue Einsichten in die Rolle diese Faktoren während der Krebsentwicklung in vivo zu erlangen. Weiterhin ermöglichen diese transgenen Linien durch einfaches Auskreuzen auf Xmrk Linien, deren Einfluss auf die Verbreitung von Melanomen zu untersuchen. Letztendlich sind mit diesen Linien auch Untersuchungen der Entwicklung von Pigmentzellen über Zeit möglich, da die Embryonen transparent sind und sich für chemisches Hochdurchsatz-Screening eignen.
urn:nbn:de:bvb:20-opus-70762
7076
X124000
Luciana Alcantarino Menescal
deu
swd
Japankärpfling
deu
swd
Melanom
deu
swd
Myc
deu
swd
Molekulargenetik
deu
uncontrolled
melanoma
deu
uncontrolled
medaka
deu
uncontrolled
BRAF
deu
uncontrolled
Stat5
deu
uncontrolled
c-myc
eng
uncontrolled
melanoma
eng
uncontrolled
medaka
eng
uncontrolled
BRAF
eng
uncontrolled
Stat5
eng
uncontrolled
c-myc
Biowissenschaften; Biologie
open_access
Graduate School of Life Sciences
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/5824/MenescalDiss.pdf
19696
2018
eng
675
9
article
1
--
2018-12-18
--
Ras-Induced miR-146a and 193a Target Jmjd6 to Regulate Melanoma Progression
Ras genes are among the most commonly mutated genes in human cancer; yet our understanding of their oncogenic activity at the molecular mechanistic level is incomplete. To identify downstream events that mediate ras-induced cellular transformation in vivo, we analyzed global microRNA expression in three different models of Ras-induction and tumor formation in zebrafish. Six microRNAs were found increased in Ras-induced melanoma, glioma and in an inducible model of ubiquitous Ras expression. The upregulation of the microRNAs depended on the activation of the ERK and AKT pathways and to a lesser extent, on mTOR signaling. Two Ras-induced microRNAs (miR-146a and 193a) target Jmjd6, inducing downregulation of its mRNA and protein levels at the onset of Ras expression during melanoma development. However, at later stages of melanoma progression, jmjd6 levels were found elevated. The dynamic of Jmjd6 levels during progression of melanoma in the zebrafish model suggests that upregulation of the microRNAs targeting Jmjd6 may be part of an anti-cancer response. Indeed, triple transgenic fish engineered to express a microRNA-resistant Jmjd6 from the onset of melanoma have increased tumor burden, higher infiltration of leukocytes and shorter melanoma-free survival. Increased JMJD6 expression is found in several human cancers, including melanoma, suggesting that the up-regulation of Jmjd6 is a critical event in tumor progression.
The following link has been created to allow review of record GSE37015: http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?token=jjcrbiuicyyqgpc&acc=GSE37015.
Frontiers in Genetics
1664-8021
10.3389/fgene.2018.00675
urn:nbn:de:bvb:20-opus-196963
Frontiers in Genetics (2018) 9:675. doi: 10.3389/fgene.2018.00675
667787
037220
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Viviana Anelli
Anita Ordas
Susanne Kneitz
Leonel Munoz Sagredo
Victor Gourain
Manfred Schartl
Annemarie H. Meijer
Marina Mione
eng
uncontrolled
zebrafish
eng
uncontrolled
cancer models
eng
uncontrolled
microRNA
eng
uncontrolled
Jmjd6
eng
uncontrolled
ras
eng
uncontrolled
melanoma
eng
uncontrolled
miR-146a
eng
uncontrolled
miR-193a
Medizin und Gesundheit
open_access
Theodor-Boveri-Institut für Biowissenschaften
OpenAIRE
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/19696/fgene-09-00675.pdf
29042
2022
eng
19
23
article
1
--
2022-10-01
--
Homozygous CRISPR/Cas9 knockout generated a novel functionally active exon 1 skipping XPA variant in melanoma cells
Defects in DNA repair pathways have been associated with an improved response to immune checkpoint inhibition (ICI). In particular, patients with the nucleotide excision repair (NER) defect disease Xeroderma pigmentosum (XP) responded impressively well to ICI treatment. Recently, in melanoma patients, pretherapeutic XP gene expression was predictive for anti-programmed cell death-1 (PD-1) ICI response. The underlying mechanisms of this finding are still to be revealed. Therefore, we used CRISPR/Cas9 to disrupt XPA in A375 melanoma cells. The resulting subclonal cell lines were investigated by Sanger sequencing. Based on their genetic sequence, candidates from XPA exon 1 and 2 were selected and further analyzed by immunoblotting, immunofluorescence, HCR and MTT assays. In XPA exon 1, we established a homozygous (c.19delG; p.A7Lfs*8) and a compound heterozygous (c.19delG/c.19_20insG; p.A7Lfs*8/p.A7Gfs*55) cell line. In XPA exon 2, we generated a compound heterozygous mutated cell line (c.206_208delTTG/c.208_209delGA; p.I69_D70delinsN/p.D70Hfs*31). The better performance of the homozygous than the heterozygous mutated exon 1 cells in DNA damage repair (HCR) and post-UV-C cell survival (MTT), was associated with the expression of a novel XPA protein variant. The results of our study serve as the fundamental basis for the investigation of the immunological consequences of XPA disruption in melanoma.
International Journal of Molecular Sciences
1422-0067
10.3390/ijms231911649
urn:nbn:de:bvb:20-opus-290427
2022-11-04T12:24:20+00:00
sword
swordwue
attachment; filename=deposit.zip
9834c8d8230200ca4822c30c3121e6bb
International Journal of Molecular Sciences (2022) 23:19, 11649. https://doi.org/10.3390/ijms231911649
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Veronika Banicka
Marie Christine Martens
Rüdiger Panzer
David Schrama
Steffen Emmert
Lars Boeckmann
Alexander Thiem
eng
uncontrolled
DNA repair
eng
uncontrolled
nucleotide excision repair
eng
uncontrolled
XPA
eng
uncontrolled
CRISPR
eng
uncontrolled
knockout
eng
uncontrolled
protein variant
eng
uncontrolled
melanoma
eng
uncontrolled
A375
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/29042/ijms-23-11649.pdf
12621
2012
eng
2091-2103
11
61
article
1
2016-01-29
--
--
Survivin-specific T-cell reactivity correlates with tumor response and patient survival: a phase-II peptide vaccination trial in metastatic melanoma
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.
Cancer Immunology, Immunotherapy
10.1007/s00262-012-1266-9
urn:nbn:de:bvb:20-opus-126215
Cancer Immunology Immunotherapy (2012) 61:2091–2103 DOI 10.1007/s00262-012-1266-9
Jürgen C. Becker
Mads H. Andersen
Valeska Hofmeister-Müller
Marion Wobser
Lidia Frey
Christiane Sandig
Steffen Walter
Harpreet Singh-Jasuja
Eckhart Kämpgen
Andreas Opitz
Marc Zapatka
Eva-B. Bröcker
Per thor Straten
David Schrama
Selma Ugurel
eng
uncontrolled
peptide vaccination
eng
uncontrolled
therapy
eng
uncontrolled
survivin T-cell reactivity
eng
uncontrolled
melanoma
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/12621/262_2012_Article_1266.pdf
12483
2012
eng
2091-2103
11
61
article
1
2016-01-22
--
--
Survivin-specific T-cell reactivity correlates with tumor response and patient survival: a phase-II peptide vaccination trial in metastatic melanoma
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.
Cancer Immunology, Immunotherapy
10.1007/s00262-012-1266-9
urn:nbn:de:bvb:20-opus-124830
Cancer Immunology Immunotherapy (2012) 61:2091–2103 DOI 10.1007/s00262-012-1266-9
Jürgen C. Becker
Mads H. Andersen
Valeska Hofmeister-Müller
Marion Wobser
Lidia Frey
Christiane Sandig
Steffen Walter
Harpreet Singh-Jasuja
Eckhart Kämpgen
Andreas Opitz
Marc Zapatka
Eva-B. Bröcker
Per thor Straten
David Schrama
Selma Ugurel
eng
uncontrolled
peptide vaccination
eng
uncontrolled
melanoma
eng
uncontrolled
survivin
eng
uncontrolled
T-cell reactivity
eng
uncontrolled
therapy
Krankheiten
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Institut für Klinische Transfusionsmedizin und Hämotherapie
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/12483/Becker_2Fs00262-012-1266-9.pdf
26219
2022
eng
3
14
article
1
--
2022-02-02
--
Antibody–drug conjugates as an emerging therapy in oncodermatology
Antibody–drug conjugates (ADCs) are an emerging class of therapeutics, with twelve FDA- and EMA-approved drugs for hematological and solid cancers. Such drugs consist in a monoclonal antibody linked to a cytotoxic agent, allowing a specific cytotoxicity to tumor cells. In recent years, tremendous progress has been observed in therapeutic approaches for advanced skin cancer patients. In this regard, targeted therapies (e.g., kinase inhibitors) or immune checkpoint-blocking antibodies outperformed conventional chemotherapy, with proven benefit to survival. Nevertheless, primary and acquired resistances as well as adverse events remain limitations of these therapies. Therefore, ADCs appear as an emerging therapeutic option in oncodermatology. After providing an overview of ADC design and development, the goal of this article is to review the potential ADC indications in the field of oncodermatology.
Cancers
2072-6694
10.3390/cancers14030778
urn:nbn:de:bvb:20-opus-262192
2022-03-28T07:40:35+00:00
sword
swordwue
attachment; filename=deposit.zip
e9fa6524523bd711930c8bebd1888a8f
Cancers (2022) 14:3, 778. https://doi.org/10.3390/cancers14030778
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Clara Esnault
David Schrama
Roland Houben
Serge Guyétant
Audrey Desgranges
Camille Martin
Patricia Berthon
Marie-Claude Viaud-Massuard
Antoine Touzé
Thibault Kervarrec
Mahtab Samimi
eng
uncontrolled
antibody–drug conjugates
eng
uncontrolled
oncodermatology
eng
uncontrolled
melanoma
eng
uncontrolled
skin squamous cell carcinoma
eng
uncontrolled
cutaneous T-cell lymphoma and Merkel cell carcinoma
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/26219/cancers-14-00778-v4.pdf
23019
2020
eng
100
article
1
2021-03-10
--
--
Indirect Comparison of Combined BRAF and MEK Inhibition in Melanoma Patients with Elevated Baseline Lactate Dehydrogenase
The approval of BRAF and MEK inhibitors has signifi-cantly improved treatment outcomes for patients with BRAF-mutated metastatic melanoma. The 3 first-line targeted therapy trials have provided similar results, and thus the identification of predictive biomarkers may generate a more precise basis for clinical deci-sion-making. Elevated baseline lactate dehydrogenase (LDH) has already been determined as a strong prog-nostic factor. Therefore, this indirect analysis compa-red subgroups with elevated baseline LDH across the pivotal targeted therapy trials co-BRIM, COMBI-v and COLUMBUS part 1. The Bucher method was used to compare progression-free survival, objective response rate and overall survival indirectly. The results show a non-significant risk reduction for progression in the subgroup with elevated baseline LDH receiving vemu-rafenib plus cobimetinib compared with dabrafenib plus trametinib and encorafenib plus binimetinib. Al-though an indirect comparison, these data might pro-vide some guidance for treatment recommendations in melanoma patients with elevated LDH.
Acta Dermato-Venereologica
10.2340/00015555-3526
urn:nbn:de:bvb:20-opus-230190
publish
Acta Dermato-Venereologica 2020; 100: adv00174. doi: 10.2340/00015555-3526
true
true
CC BY-NC: Creative-Commons-Lizenz: Namensnennung, Nicht kommerziell 4.0 International
Valerie Glutsch
Teresa Amaral
Claus Garbe
Kai-Martin Thoms
Peter Mohr
Axel Hauschild
Bastian Schilling
eng
uncontrolled
melanoma
eng
uncontrolled
BRAF
eng
uncontrolled
lactate dehydrogenase
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Förderzeitraum 2020
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/23019/5780.pdf
17726
2018
eng
71
7
article
1
2019-02-25
--
--
BRAF inhibition causes resilience of melanoma cell lines by inducing the secretion of FGF1
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.
Oncogenesis
10.1038/s41389-018-0082-2
urn:nbn:de:bvb:20-opus-177261
Oncogenesis (2018) 7:71. DOI: 10.1038/s41389-018-0082-2
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Johannes Grimm
Anita Hufnagel
Marion Wobser
Andreas Borst
Sebastian Haferkamp
Roland Houben
Svenja Meierjohann
eng
uncontrolled
melanoma
eng
uncontrolled
senescence
eng
uncontrolled
BRAF
eng
uncontrolled
tumor
Medizin und Gesundheit
open_access
Theodor-Boveri-Institut für Biowissenschaften
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Förderzeitraum 2018
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/17726/Grimm_Oncogenesis.pdf
13139
2012
eng
e31255
2
7
article
1
2016-04-06
--
--
Activation of the PI3K/AKT Pathway in Merkel Cell Carcinoma
Merkel cell carcinoma (MCC) is a highly aggressive skin cancer with an increasing incidence. The understanding of the molecular carcinogenesis of MCC is limited. Here, we scrutinized the PI3K/AKT pathway, one of the major pathways activated in human cancer, in MCC. Immunohistochemical analysis of 41 tumor tissues and 9 MCC cell lines revealed high levels of AKT phosphorylation at threonine 308 in 88% of samples. Notably, the AKT phosphorylation was not correlated with the presence or absence of the Merkel cell polyoma virus (MCV). Accordingly, knock-down of the large and small T antigen by shRNA in MCV positive MCC cells did not affect phosphorylation of AKT. We also analyzed 46 MCC samples for activating PIK3CA and AKT1 mutations. Oncogenic PIK3CA mutations were found in 2/46 (4%) MCCs whereas mutations in exon 4 of AKT1 were absent. MCC cell lines demonstrated a high sensitivity towards the PI3K inhibitor LY-294002. This finding together with our observation that the PI3K/AKT pathway is activated in the majority of human MCCs identifies PI3K/AKT as a potential new therapeutic target for MCC patients.
PLoS One
10.1371/journal.pone.0031255
urn:nbn:de:bvb:20-opus-131398
PLoS ONE 7(2): e31255. doi:10.1371/journal.pone.0031255
Christian Hafner
Roland Houben
Anne Baeurle
Cathrin Ritter
David Schrama
Michael Landthaler
Jürgen C. Becker
eng
uncontrolled
rare
eng
uncontrolled
T-antigen
eng
uncontrolled
PIK3CA mutations
eng
uncontrolled
squamous cell
eng
uncontrolled
melanoma
eng
uncontrolled
polymavirus
eng
uncontrolled
cancer
eng
uncontrolled
tumors
eng
uncontrolled
akt
eng
uncontrolled
expression
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/13139/Hafner_journal.pone.0031255.pdf
14240
2011
eng
347-353
20
108
article
1
2016-12-22
--
--
Skin Tumors in Childhood
Background:
Dermatologists, paediatricians, and general practitioners are often consulted by worried parents for the evaluation of a cutaneous tumor.
Methods:
Selective literature review.
Results:
Only 1-2% of skin tumors excised in children turn out to be malignant when examined histologically. Warning signs of malignancy include rapid growth, firm consistency, diameter exceeding 3 cm, ulceration, a non-movable mass, and presence in the neonatal period. The more common malignant skin tumors in adults-basal cell carcinoma, cutaneous squamous cell carcinoma, and melanoma-are very rare in childhood. Congenital melanocytic nevi and sebaceous nevi bear a lower malignant potential than previously believed; nevertheless, their excision is often indicated. A Spitz nevus can mimic a melanoma both clinically and histologically. Some benign skin tumors of childhood tend to regress spontaneously within a few years but may cause complications at particular locations and when multiple. For infantile hemangiomas requiring systemic treatment because of imminent obstruction or ulceration, propranolol seems to have a far more favorable risk-benefit ratio than corticosteroids.
Conclusion:
Physicians need specialized knowledge in order to decide whether a skin tumor in a child should be excised, non-surgically treated, or further evaluated, or whether it can be safely left untreated because of the likelihood of spontaneous remission.
Deutsches Ärzteblatt International
10.3238/arztebl.2011.0347
urn:nbn:de:bvb:20-opus-142402
Deutsches Ärzteblatt International 2011; 108(20): 347–53 DOI: 10.3238/arztebl.2011.0347
false
true
Deutsches Urheberrecht
Henning Hamm
Peter H Höger
eng
uncontrolled
congenital melanocytic nevi
eng
uncontrolled
mastocytosis
eng
uncontrolled
diagnosis
eng
uncontrolled
melanoma
eng
uncontrolled
children
eng
uncontrolled
lumps
Gynäkologie, Geburtsmedizin, Pädiatrie, Geriatrie
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Universität Würzburg
13710
2015
eng
40836
40849
38
6
article
1
2016-08-08
--
--
Distribution and prognostic relevance of tumor-infiltrating lymphocytes (TILs) and PD-1/PD-L1 immune checkpoints in human brain metastases
The activation of immune cells by targeting checkpoint inhibitors showed promising results with increased patient survival in distinct primary cancers. Since only limited data exist for human brain metastases, we aimed at characterizing tumor infiltrating lymphocytes (TILs) and expression of immune checkpoints in the respective tumors. Two brain metastases cohorts, a mixed entity cohort (n = 252) and a breast carcinoma validation cohort (n = 96) were analyzed for CD3+, CD8+, FOXP3+, PD-1+ lymphocytes and PD-L1+ tumor cells by immunohistochemistry. Analyses for association with clinico-epidemiological and neuroradiological parameters such as patient survival or tumor size were performed. TILs infiltrated brain metastases in three different patterns (stromal, peritumoral, diffuse). While carcinomas often show a strong stromal infiltration, TILs in melanomas often diffusely infiltrate the tumors. Highest levels of CD3+ and CD8+ lymphocytes were seen in renal cell carcinomas (RCC) and strongest PD-1 levels on RCCs and melanomas. High amounts of TILs, high ratios of PD-1+/CD8+ cells and high levels of PD-L1 were negatively correlated with brain metastases size, indicating that in smaller brain metastases CD8+ immune response might get blocked. PD-L1 expression strongly correlated with TILs and FOXP3 expression. No significant association of patient survival with TILs was observed, while high levels of PD-L1 showed a strong trend towards better survival in melanoma brain metastases (Log-Rank p = 0.0537). In summary, melanomas and RCCs seem to be the most immunogenic entities. Differences in immunotherapeutic response between tumor entities regarding brain metastases might be attributable to this finding and need further investigation in larger patient cohorts.
Oncotarget
10.18632/oncotarget.5696
PMC4747372
urn:nbn:de:bvb:20-opus-137107
Oncotarget, Vol. 6, No. 38, p. 40836-40849. DOI 10.18632/oncotarget.5696
Patrick N. Harter
Simon Bernatz
Alexander Scholz
Pia S. Zeiner
Jenny Zinke
Makoto Kiyose
Stella Blasel
Rudi Beschorner
Christian Senft
Benjamin Bender
Michael W. Ronellenfitsch
Harriet Wikman
Markus Glatzel
Matthias Meinhardt
Tareq A. Juratli
Joachim P. Steinbach
Karl H. Plate
Jörg Wischhusen
Benjamin Weide
Michel Mittelbronn
eng
uncontrolled
B7-H1
eng
uncontrolled
PD-L1
eng
uncontrolled
immunoresistance
eng
uncontrolled
immunosurveillance
eng
uncontrolled
safety
eng
uncontrolled
survival
eng
uncontrolled
expression
eng
uncontrolled
melanoma
eng
uncontrolled
breast cancer
eng
uncontrolled
PC-1 blockade
eng
uncontrolled
cell lung cancer
eng
uncontrolled
tumor-infiltrating lymphocytes
eng
uncontrolled
brain metastases
eng
uncontrolled
PD-1
Gynäkologie, Geburtsmedizin, Pädiatrie, Geriatrie
open_access
Frauenklinik und Poliklinik
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/13710/5696-97133-1-PB.pdf
7217
2012
eng
doctoralthesis
1
2012-12-20
--
2012-12-14
Regulation of ERK1/2 signaling in melanoma
Regulation des ERK1/2 Signalwegs im Melanom
Die Mechanismen in einer Zelle, die die Genexpression und somit den Stoffwechsel, das Wachstum und das gesamte Zellverhalten steuern, sind ebenso bedeutsam für das Verständnis der grundlegenden Biologie einer lebenden Zelle wie für die Vorgänge der Krebsentstehung. Dabei bilden hochvernetzte, und strikt regulierte Signaltransduktionswege die Basis für ein belastbares und zugleich hochflexibles regulatorisches Netzwerk. Die Störung solcher Signalkaskaden kann zum einen ursächlich aber auch modifizierend auf die Bildung von Tumoren wirken. Die von Rezeptortyrosinkinasen (RTK) und RAS abhängigen Signalwege, die zur Aktivierung von AKT und ERK1/2 führen, sind hierbei von besonderem Interesse für die Entstehung des malignen Melanoms. Mutationen in Komponenten dieser Wege (z.B. NRAS, BRAF oder PTEN), die die Signalstärke erhöhen kommen in Melanomen sehr häufig vor. Im ersten Teil dieser Arbeit wurden die unterschiedlichen und vielfältigen Funktionen von MKP2, einem Feedbackregulator des ERK1/2-Weges, unter verschiedenen zellulären Rahmenbedingungen, untersucht. Des Weiteren wird eine Funktion des zum AP1-Komplex gehörenden FOSL1, einem unter transkriptioneller Kontrolle des ERK1/2-Weges stehendem Transkriptionsfaktors, hinsichtlich der Steuerung der Zell-Proliferation gezeigt. Weiterhin habe ich Aspekte der direkten pharmakologischen Inhibition des ERK1/2-Weges hinsichtlich ihres Effekts auf die Auslösung von Apoptose untersucht. Aufgrund der Häufigkeit von Mutationen in Genen, die für Proteine des ERK1/2-Weges kodieren (z.B. NRASQ61K, BRAFV600E), gilt die Inhibition dieses Signalwegs als vielversprechende Strategie zur Behandlung des Melanoms. Auch wenn klinische Studien, die Inhibitoren für MEK oder RAF als Einzelmedikamente verwenden, bei mehrmonatiger Behandlung sehr erfolgreich sind, konnten so keine langfristigen Erfolge erzielt werden. Aus diesem Grund werden nun Kombinationstherapien, die einen Inhibitor des ERK1/2-Weges und eine weitere Form der Therapie kombinieren, untersucht. Der zweite Teil dieser Arbeit beschreibt, dass der spezifische MEK Inhibitor PD184352 Melanomzellen vor der Apoptosewirkung von Cisplatin schützen kann. Einzelbehandlung mit Cisplatin führt hierbei zur Akkumulation von DNA Schäden, die wiederum Caspase-abhängig Apoptose induzieren. Zusätzliche Anwendung des MEK Inhibitors verringerte jedoch in einigen Zelllinien das Potential von Cisplatin, Apoptose auszulösen. Diese Zellen zeigten eine verstärkte Aktivierung der Serin/Threonin-KInase AKT nach MEK Inhibition. Diese AKT Aktivierung führte zur Inaktivierung der FOXO Transkriptionsfaktoren, was wiederum die Expression des pro-apoptotischen BH3-only Proteins PUMA verringerte. PUMA selbst ist ein wichtiger Bestandteil der Apoptose Maschinerie, die durch Cisplatin aktiviert wird. Die im Rahmen dieser Arbeit erhaltenen Befunde deuten darauf hin, dass RTKs, im besonderen EGFR, bei diesem Crosstalk eine Rolle spielen. Diese Ergebnisse zeigen, dass die Inhibition des RAS/RAF/MEK/ERK Signalweges im Melanom nicht zwangsläufig von Vorteil sein muss, falls die Zellen gleichzeitig mit einem genotoxischen Medikament behandelt werden. Hier kann sie sogar die Überlebensfähigkeit von Melanomzellen unter Apoptose induzierenden Bedingungen verbessern.
The mechanisms that enable cells to regulate their gene expression and thus their metabolism, proliferation or cellular behaviour are not only important to understand the basic biology of a living cell, but are also of crucial interest in cancerogenesis. Highly interwoven and tightly regulated pathways are the basis of a robust but also flexible regulatory network. Interference with these pathways can be either causative for tumorigenesis or can modify its outcome. The receptor tyrosine kinase (RTK) and RAS dependent pathways leading to AKT or ERK1/2 activation are of particular interest in melanoma. These signaling modules are commonly activated by different mutations that can be found in various pathway components like NRAS, BRAF or PTEN. The first part of this work deals with the diverse and versatile functions of the ERK1/2 pathway feedbackregulator MKP2 in different cellular, melanoma relevant settings. In addition, a functional role of the AP1-complex member FOSL1, an ERK1/2 transcriptional target being implicated in the regulation of proliferation, is demonstrated. Secondly, aspects of direct pharmacological inhibition of the ERK1/2 pathway with regard to the induction of apoptosis have been analysed. Due to the high frequency of melanoma related mutations occurring in the RAS/RAF/MEK/ERK pathway (e.g. NRASQ61K, BRAFV600E), inhibition of this signaling cascade is deemed to be a promising therapeutic strategy for the treatment of malignant melanoma. However, although in clinical trials mono-therapeutic treatment with MEK- or RAF inhibitors was successful in the short run, it failed to show satisfactory long-lasting effects. Hence, combination therapies using a MAPK pathway inhibitor and an additional therapy are currently under investigation. I was able to demonstrate that inhibition of MEK using the highly specific inhibitor PD184352 can have a protective effect on melanoma cells with regard to their susceptibility towards the apoptosis inducing agent cisplatin. Single application of cisplatin led to strong DNA damage and the induction of caspase-dependent apoptosis. Additional administration of the MEK inhibitor, however, strongly reduced the apoptosis inducing effect of cisplatin in several melanoma cell lines, These cells displayed an increased activation of the serine/threonine kinase AKT after MEK inhibition. This AKT activation concomitantly led to the phosphorylation of FOXO transcription factors, attenuating the cisplatin induced expression of the BH3-only protein PUMA. PUMA in turn was important to mediate the apoptosis machinery after cisplatin treatment. My results also indicate a participation of RTKs, in particular EGFR, in mediating MEK inhibitor induced activation of AKT. These results demonstrate that inhibition of the RAS/RAF/MEK/ERK signaling pathway in melanoma cell lines does not necessilary have favourable effects in a cytotoxic co-treatment situation. Instead, it can even enhance melanoma survival under pro-apoptotic conditions.
7449
urn:nbn:de:bvb:20-opus-85727
X 124326
Deutsches Urheberrecht
Johannes Haydn
deu
swd
Melanom
deu
swd
MAP-Kinase
eng
uncontrolled
melanoma
eng
uncontrolled
MAP-Kinase
eng
uncontrolled
ERK signaling
deu
swd
Signalkette
Biowissenschaften; Biologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/7217/DissHaydn.pdf
12064
2014
eng
5040-53
13
5
article
1
2015-10-21
--
--
The MAPK pathway as an apoptosis enhancer in melanoma
Inhibition of RAF/MEK/ERK signaling is beneficial for many patients with BRAFV600E–mutated melanoma. However, primary and secondary resistances restrict long-lasting therapy success. Combination therapies are therefore urgently needed. Here, we evaluate the cellular effect of combining a MEK inhibitor with a genotoxic apoptosis inducer. Strikingly, we observed that an activated MAPK pathway promotes in several melanoma cell lines the pro-apoptotic response to genotoxic stress, and MEK inhibition reduces intrinsic apoptosis. This goes along with MEK inhibitor induced increased RAS and P-AKT levels. The protective effect of the MEK inhibitor depends on PI3K signaling, which prevents the induction of pro-apoptotic PUMA that mediates apoptosis after DNA damage. We could show that the MEK inhibitor dependent feedback loop is enabled by several factors, including EGF receptor and members of the SPRED family. The simultaneous knockdown of SPRED1 and SPRED2 mimicked the effects of MEK inhibitor such as PUMA repression and protection from apoptosis. Our data demonstrate that MEK inhibition of BRAFV600E-positive melanoma cells can protect from genotoxic stress, thereby achieving the opposite of the intended anti-tumorigenic effect of the combination of MEK inhibitor with inducers of intrinsic apoptosis.
Oncotarget
1949-2553
urn:nbn:de:bvb:20-opus-120649
Oncotarget, Vol. 5, No. 13, 5040-53
Johannes M. Haydn
Anita Hufnagel
Johannes Grimm
Katja Maurus
Manfred Schartl
Svenja Meierjohann
eng
uncontrolled
PI3K
eng
uncontrolled
melanoma
eng
uncontrolled
RAS
eng
uncontrolled
chemotherapy resistance
eng
uncontrolled
crosstalk
Pharmakologie, Therapeutik
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/12064/110_Hydn_Oncotarget.pdf
26061
2021
eng
10
16
article
1
2022-03-16
--
--
Differential expression of transposable elements in the medaka melanoma model
Malignant melanoma incidence is rising worldwide. Its treatment in an advanced state is difficult, and the prognosis of this severe disease is still very poor. One major source of these difficulties is the high rate of metastasis and increased genomic instability leading to a high mutation rate and the development of resistance against therapeutic approaches. Here we investigate as one source of genomic instability the contribution of activation of transposable elements (TEs) within the tumor. We used the well-established medaka melanoma model and RNA-sequencing to investigate the differential expression of TEs in wildtype and transgenic fish carrying melanoma. We constructed a medaka-specific TE sequence library and identified TE sequences that were specifically upregulated in tumors. Validation by qRT- PCR confirmed a specific upregulation of a LINE and an LTR element in malignant melanomas of transgenic fish.
PLoS One
10.1371/journal.pone.0251713
urn:nbn:de:bvb:20-opus-260615
publish
PLoS One (2021) 16:10, e0251713. https://doi.org/10.1371/journal.pone.0251713
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Frederik Helmprobst
Susanne Kneitz
Barbara Klotz
Magali Naville
Corentin Dechaud
Jean-Nicolas Volff
Manfred Schartl
eng
uncontrolled
melanoma
eng
uncontrolled
genomics
eng
uncontrolled
transposable elements
eng
uncontrolled
cancer genomics
eng
uncontrolled
malignant tumors
eng
uncontrolled
gene prediction
eng
uncontrolled
human genomics
eng
uncontrolled
retrotransposons
Medizin und Gesundheit
open_access
Theodor-Boveri-Institut für Biowissenschaften
Förderzeitraum 2021
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/26061/journal.pone.0251713.pdf
17364
2017
eng
578-586
3
21
article
1
2018-12-04
--
--
Prolonged IKK\(\beta\) Inhibition Improves Ongoing CTL Antitumor Responses by Incapacitating Regulatory T Cells
Regulatory T cells (Tregs) prevent autoimmunity but limit antitumor immunity. The canonical NF-\(\kappa\)B signaling pathway both activates immunity and promotes thymic Treg development. Here, we report that mature Tregs continue to require NF-\(\kappa\)B signaling through I\(\kappa\)B-kinase \(\beta\) (IKK\(\beta\)) after thymic egress. Mice lacking IKK\(\beta\) in mature Tregs developed scurfy-like immunopathology due to death of peripheral FoxP3\(^+\) Tregs. Also, pharmacological IKK\(\beta\) inhibition reduced Treg numbers in the circulation by ~50% and downregulated FoxP3 and CD25 expression and STAT5 phosphorylation. In contrast, activated cytotoxic T lymphocytes (CTLs) were resistant to IKK\(\beta\) inhibition because other pathways, in particular nuclear factor of activated T cells (NFATc1) signaling, sustained their survival and expansion. In a melanoma mouse model, IKK\(\beta\) inhibition after CTL cross-priming improved the antitumor response and delayed tumor growth. In conclusion, prolonged IKK\(\beta\) inhibition decimates circulating Tregs and improves CTL responses when commenced after tumor vaccination, indicating that IKK\(\beta\) represents a druggable checkpoint.
Cell Reports
10.1016/j.celrep.2017.09.082
29045828
urn:nbn:de:bvb:20-opus-173643
Cell Reports (2017) 21:3, pp. 578-586. https://doi.org/10.1016/j.celrep.2017.09.082
668036
true
true
CC BY-NC-ND: Creative-Commons-Lizenz: Namensnennung, Nicht kommerziell, Keine Bearbeitungen 4.0 International
Christoph Heuser
Janine Gotot
Eveline Christina Piotrowski
Marie-Sophie Philipp
Christina Johanna Felicia Courrèges
Martin Sylvester Otte
Linlin Guo
Jonathan Leo Schmid-Burgk
Veit Hornung
Annkristin Heine
Percy Alexander Knolle
Natalio Garbi
Edgar Serfling
César Evaristo
Friedrich Thaiss
Christian Kurts
eng
uncontrolled
medicine
eng
uncontrolled
regulatory T cells
eng
uncontrolled
NF-\(\kappa\)B pathway
eng
uncontrolled
tumor vaccination
eng
uncontrolled
checkpoint inhibition
eng
uncontrolled
cytotoxic T cells
eng
uncontrolled
cross-priming
eng
uncontrolled
apoptosis
eng
uncontrolled
tumor immunology
eng
uncontrolled
melanoma
Medizin und Gesundheit
open_access
Pathologisches Institut
OpenAIRE
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/17364/Heuser_1-s2.0-S2211124717313876-main.pdf
23892
2021
eng
2140
2155
8
15
article
1
--
--
--
The transmembrane protein LRIG1 triggers melanocytic tumor development following chemically induced skin carcinogenesis
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.
Molecular Oncology
10.1002/1878-0261.12945
urn:nbn:de:bvb:20-opus-238925
2021-06-01T13:25:56+00:00
sword
swordwue
attachment; filename=deposit.zip
b2ada1d22e763cbd4c65981bb06e2bfc
Molecular Oncology 2021, 15(8):2140-2155. DOI: 10.1002/1878-0261.12945
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Christine Hoesl
Thomas Fröhlich
Christian Posch
Hermann Kneitz
Matthias Goebeler
Marlon R. Schneider
Maik Dahlhoff
eng
uncontrolled
ERBB receptors
eng
uncontrolled
LRIG1
eng
uncontrolled
melanoma
eng
uncontrolled
mouse model
eng
uncontrolled
skin carcinogenesis
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/23892/Hoesl_Molecular.pdf
12219
2013
eng
919-934
5
article
1
2015-11-19
--
--
The neural crest transcription factor Brn3a is expressed in melanoma and required for cell cycle progression and survival
Pigment cells and neuronal cells both are derived from the neural crest. Here, we describe the Pit-Oct-Unc (POU) domain transcription factor Brn3a, normally involved in neuronal development, to be frequently expressed in melanoma, but not in melanocytes and nevi. RNAi-mediated silencing of Brn3a strongly reduced the viability of melanoma cell lines and decreased tumour growth in vivo. In melanoma cell lines, inhibition of Brn3a caused DNA double-strand breaks as evidenced by Mre11/Rad50-containing nuclear foci. Activated DNA damage signalling caused stabilization of the tumour suppressor p53, which resulted in cell cycle arrest and apoptosis. When Brn3a was ectopically expressed in primary melanocytes and fibroblasts, anchorage-independent growth was increased. In tumourigenic melanocytes and fibroblasts, Brn3a accelerated tumour growth in vivo. Furthermore, Brn3a cooperated with proliferation pathways such as oncogenic BRAF, by reducing oncogene-induced senescence in non-malignant melanocytes. Together, these results identify Brn3a as a new factor in melanoma that is essential for melanoma cell survival and that promotes melanocytic transformation and tumourigenesis.
EMBO Molecular Medicine
10.1002/emmm.201201862
1757-4676
urn:nbn:de:bvb:20-opus-122193
EMBO Molecular Medicine (2013) 5, 919–934. DOI 10.1002/emmm.201201862
Tobias Hohenauer
Carola Berking
Andreas Schmidt
Sebastian Haferkamp
Daniela Senft
Claudia Kammerbauer
Sabine Fraschka
Saskia Anna Graf
Martin Irmler
Johannes Beckers
Michael Flaig
Achim Aigner
Sabrina Höbel
Franziska Hoffmann
Heiko Hermeking
Simon Rothenfusser
Stefan Endres
Thomas Ruzicka
Robert Besch
eng
uncontrolled
oncogene-induced senescence
eng
uncontrolled
BRN-3A
eng
uncontrolled
DNA
eng
uncontrolled
DNA damage
eng
uncontrolled
tumourigenesis
eng
uncontrolled
P53
eng
uncontrolled
in-vitro
eng
uncontrolled
neural crest factors
eng
uncontrolled
family
eng
uncontrolled
apoptosis
eng
uncontrolled
melanoma
eng
uncontrolled
BRAF mutations
eng
uncontrolled
domain
Biochemie
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/12219/024_Hohenauer_Embo_Molecular_Medicine.pdf
28810
2022
eng
19
14
article
1
--
2022-09-20
--
Monitoring of dabrafenib and trametinib in serum and self-sampled capillary blood in patients with BRAFV600-mutant melanoma
Simple Summary
In melanoma patients treated with dabrafenib and trametinib, dose reductions and treatment discontinuations related to adverse events (AE) occur frequently. However, the associations between patient characteristics, AE, and exposure are unclear. Our prospective study analyzed serum (hydroxy-)dabrafenib and trametinib exposure and investigated its association with toxicity and patient characteristics. Additionally, the feasibility of at-home sampling of capillary blood was assessed, and a model to convert capillary blood concentrations to serum concentrations was developed. (Hydroxy-)dabrafenib or trametinib exposure was not associated with age, sex, body mass index, or AE. Co-medication with P-glycoprotein inducers was associated with lower trough concentrations of trametinib but not (hydroxy-)dabrafenib. The applicability of the self-sampling of capillary blood was demonstrated. Our conversion model was adequate for estimating serum exposure from micro-samples. The monitoring of dabrafenib and trametinib may be useful for dose modification and can be optimized by at-home sampling and our new conversion model.
Abstract
Patients treated with dabrafenib and trametinib for BRAF\(^{V600}\)-mutant melanoma often experience dose reductions and treatment discontinuations. Current knowledge about the associations between patient characteristics, adverse events (AE), and exposure is inconclusive. Our study included 27 patients (including 18 patients for micro-sampling). Dabrafenib and trametinib exposure was prospectively analyzed, and the relevant patient characteristics and AE were reported. Their association with the observed concentrations and Bayesian estimates of the pharmacokinetic (PK) parameters of (hydroxy-)dabrafenib and trametinib were investigated. Further, the feasibility of at-home sampling of capillary blood was assessed. A population pharmacokinetic (popPK) model-informed conversion model was developed to derive serum PK parameters from self-sampled capillary blood. Results showed that (hydroxy-)dabrafenib or trametinib exposure was not associated with age, sex, body mass index, or toxicity. Co-medication with P-glycoprotein inducers was associated with significantly lower trough concentrations of trametinib (p = 0.027) but not (hydroxy-)dabrafenib. Self-sampling of capillary blood was feasible for use in routine care. Our conversion model was adequate for estimating serum PK parameters from micro-samples. Findings do not support a general recommendation for monitoring dabrafenib and trametinib but suggest that monitoring can facilitate making decisions about dosage adjustments. To this end, micro-sampling and the newly developed conversion model may be useful for estimating precise PK parameters.
Cancers
2072-6694
10.3390/cancers14194566
urn:nbn:de:bvb:20-opus-288109
2022-10-06T11:57:41+00:00
sword
swordwue
attachment; filename=deposit.zip
8084b9c4a404a19b4a56e2d617ea2c10
Cancers (2022) 14:19, 4566. doi:10.3390/cancers14194566
Zentraleinheit Klinische Massenspektrometrie
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Nora Isberner
Anja Gesierich
David Balakirouchenane
Bastian Schilling
Fatemeh Aghai-Trommeschlaeger
Sebastian Zimmermann
Max Kurlbaum
Alicja Puszkiel
Benoit Blanchet
Hartwig Klinker
Oliver Scherf-Clavel
eng
uncontrolled
dabrafenib
eng
uncontrolled
trametinib
eng
uncontrolled
hydroxy-dabrafenib
eng
uncontrolled
melanoma
eng
uncontrolled
BRAF mutation
eng
uncontrolled
volumetric absorptive micro-sampling (VAMS)
eng
uncontrolled
at-home sampling
eng
uncontrolled
drug monitoring
eng
uncontrolled
population pharmacokinetics
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Medizinische Klinik und Poliklinik I
Medizinische Klinik und Poliklinik II
Institut für Pharmazie und Lebensmittelchemie
Import
Förderzeitraum 2022
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/28810/cancers-14-04566-v2.pdf
14602
2016
eng
357
17
article
1
2017-03-22
--
--
Germ cell and tumor associated piRNAs in the medaka and \(Xiphophorus\) melanoma models
Background
A growing number of studies report an abnormal expression of Piwi-interacting RNAs (piRNAs) and the piRNA processing enzyme Piwi in many cancers. Whether this finding is an epiphenomenon of the chaotic molecular biology of the fast dividing, neoplastically transformed cells or is functionally relevant to tumorigenesisis is difficult to discern at present. To better understand the role of piRNAs in cancer development small laboratory fish models can make a valuable contribution. However, little is known about piRNAs in somatic and neoplastic tissues of fish.
Results
To identify piRNA clusters that might be involved in melanoma pathogenesis, we use several transgenic lines of medaka, and platyfish/swordtail hybrids, which develop various types of melanoma. In these tumors Piwi, is expressed at different levels, depending on tumor type. To quantify piRNA levels, whole piRNA populations of testes and melanomas of different histotypes were sequenced. Because no reference piRNA cluster set for medaka or Xiphophorus was yet available we developed a software pipeline to detect piRNA clusters in our samples and clusters were selected that were enriched in one or more samples. We found several loci to be overexpressed or down-regulated in different melanoma subtypes as compared to hyperpigmented skin. Furthermore, cluster analysis revealed a clear distinction between testes, low-grade and high-grade malignant melanoma in medaka.
Conclusions
Our data imply that dysregulation of piRNA expression may be associated with development of melanoma. Our results also reinforce the importance of fish as a suitable model system to study the role of piRNAs in tumorigenesis.
BMC Genomics
10.1186/s12864-016-2697-z
urn:nbn:de:bvb:20-opus-146028
BMC Genomics (2016) 17:357 DOI 10.1186/s12864-016-2697-z
Susanne Kneitz
Rasmi R. Mishra
Domitille Chalopin
John Postlethwait
Wesley C. Warren
Ronald B. Walther
Manfred Schartl
eng
uncontrolled
small RNA-sequencing
eng
uncontrolled
melanoma
eng
uncontrolled
piRNA
eng
uncontrolled
fish model
Menschliche Anatomie, Zytologie, Histologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
Förderzeitraum 2016
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/14602/026_Kneitz_art_10.1186_s12864-016-2697-z.pdf
21120
2020
eng
8
12
article
1
--
2020-08-18
--
Tumour progression stage-dependent secretion of YB-1 stimulates melanoma cell migration and invasion
Secreted factors play an important role in intercellular communication. Therefore, they are not only indispensable for the regulation of various physiological processes but can also decisively advance the development and progression of tumours. In the context of inflammatory disease, Y-box binding protein 1 (YB-1) is actively secreted and the extracellular protein promotes cell proliferation and migration. In malignant melanoma, intracellular YB-1 expression increases during melanoma progression and represents an unfavourable prognostic marker. Here, we show active secretion of YB-1 from melanoma cells as opposed to benign cells of the skin. Intriguingly, YB-1 secretion correlates with the stage of melanoma progression and depends on a calcium- and ATP-dependent non-classical secretory pathway leading to the occurrence of YB-1 in the extracellular space as a free protein. Along with an elevated YB-1 secretion of melanoma cells in the metastatic growth phase, extracellular YB-1 exerts a stimulating effect on melanoma cell migration, invasion, and tumourigenicity. Collectively, these data suggest that secreted YB-1 plays a functional role in melanoma cell biology, stimulating metastasis, and may serve as a novel biomarker in malignant melanoma that reflects tumour aggressiveness.
Cancers
2072-6694
10.3390/cancers12082328
urn:nbn:de:bvb:20-opus-211206
swordwue
2020-09-02T23:43:39+00:00
attachment; filename=deposit.zip
c9587b9107ccd5fd56d13e313cc3ed24
Cancers (2020) 12:8, 2328. https://doi.org/10.3390/cancers12082328
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Corinna Kosnopfel
Tobias Sinnberg
Birgit Sauer
Heike Niessner
Alina Muenchow
Birgit Fehrenbacher
Martin Schaller
Peter R. Mertens
Claus Garbe
Basant Kumar Thakur
Birgit Schittek
eng
uncontrolled
melanoma
eng
uncontrolled
secretion
eng
uncontrolled
Y-box binding protein 1
eng
uncontrolled
migration and invasiveness
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/21120/cancers-12-02328-v2.pdf
4253
2010
eng
doctoralthesis
1
2010-09-17
--
2010-09-13
Characterisation and regulation of the Egfr/Egfr ligand system in fish models for melanoma
Fish of the genus Xiphophorus belong to the oldest animal models in cancer research. The oncogene responsible for the generation of spontaneous aggressive melanoma encodes for a mutated epidermal growth factor receptor (Egfr) and is called xmrk for Xiphophorus melanoma receptor kinase. Xmrk constitutive activation mechanisms and subsequent signaling pathways have already been investigated and charaterized but it is still unknown if Egfr ligands may also play a role in Xmrk-driven melanoma formation. To investigate the potential role of Egfr ligands in Xmrk-driven melanoma, I firstly analyzed the evolution of teleost and tetrapod Egfr/Egfr ligand systems. I especially focused on the analysis on the medaka fish, a closely related species to Xiphophorus, for which the whole genome has been sequenced. I could identify all seven Egfr ligands in medaka and could show that the two teleost-specific Egfr copies of medaka display dissimilar expression patterns in adult tissues together with differential expression of Egfr ligand subsets, arguing for subfunctionalization of receptor functions in this fish. Our phylogenetic and synteny analyses supported the hypothesis that only one gene in the chordate ancestor gave rise to the diversity of Egfr ligands found in vertebrate genomes today. I also could show that the Egfr extracellular subdomains implicated in ligand binding are not evolutionary conserved between tetrapods and teleosts, making the use of heterologous ligands in experiments with fish cells debatable. Despite its well understood and straight-forward process, Xmrk-driven melanomagenesis in Xiphophorus is problematic to further investigate in vivo. Our laboratory recently established a new melanoma animal model by generating transgenic mitf::xmrk medaka fishes, a Xiphophorus closely related species offering many more advantages. These fishes express xmrk under the control of the pigment-cell specific Mitf promoter. During my PhD thesis, I participated in the molecular analysis of the stably transgenic medaka and could show that the Xmrk-induced signaling pathways are similar when comparing Xiphophorus with transgenic mitf::xmrk medaka. These data together with additional RNA expression, protein, and histology analyses showed that Xmrk expression under the control of a pigment cell-specific promoter is sufficient to induce melanoma in the transgenic medaka, which develop very stereotyped tumors, including uveal and extracutaneous melanoma, with early onset during larval stages. To further investigate the potential role of Egfr ligands in Xmrk-driven melanoma, I made use of two model systems. One of them was the above mentioned mitf::xmrk medaka, the other was an in-vitro cell culture system, where the EGF-inducible Xmrk chimera HERmrk is stably expressed in murine melanocytes. Here I could show that HERmrk activation strongly induced expression of amphiregulin (Areg) and heparin-binding EGF-like growth factor (Hbegf) in melanocytes. This regulation was dependent on the MAPK and SRC signaling pathways. Moreover, upregulation of Adam10 and Adam17, the two major sheddases of Egfr ligands, was observed. I also could demonstrate the functionality of the growth factors by invitro analyses. Using the mitf::xmrk medaka model I could also show the upregulation of a subset of ligand genes, namely egf, areg, betacellulin (btc) and epigen (epgn) as well as upregulation of medaka egfrb in tumors from fish with metastatic melanoma. All these results converge to support an Xmrk-induced autocrine Egfr ligand loop. Interestingly, my in-vitro experiments with conditioned supernatant from medaka Egf- and Hbegf-producing cells revealed that not only Xiphophorus Egfrb, but also the pre-activated Xmrk could be further stimulated by the ligands. Altogether, I could show with in-vitro and in-vivo experiments that Xmrk is capable of inducing a functional autocrine Egfr ligand loop. These data confirm the importance of autocrine loops in receptor tyrosine kinase (RTK)-dependent cancer development and show the possibility for a constitutively active RTK to strengthen its oncogenic signaling by ligand binding.
Fische der Gattung Xiphophorus gehören zu den ältesten Tiermodellen für die Krebsforschung. Das im Xiphophorus-System für die Melanomentstehung verantwortliche Onkogen codiert für eine mutierte Version des epidermalen Wachstumsfaktorrezeptors (Egfr) und wird xmrk (für “Xiphophorus melanoma receptor kinase”) genannt. Die konstitutiven Aktivierungsmechanismen dieses Rezeptors und die daraus resultierenden aktivierten Signalwege sind bereits gut untersucht und charakterisiert. Dennoch war bisher unbekannt, ob Egfr-Liganden auch eine Rolle bei der Xmrk-vermittelten Melanomentstehung spielen. Um eine potenzielle Rolle dieser Egfr-Liganden im Xmrk-induzierten Melanom zu erforschen, habe ich zunächst die Evolution des Egfr/Egfr-Liganden-Systems in Teleostiern und Tetrapoden untersucht. Hierfür fokussierte ich mich im besonderen auf den Medaka- Fisch, der zum einen eine nahe evolutionäre Verwandtschaft zu Xiphophorus aufweist und zum anderen – im Gegensatz zu Xiphophorus - ein komplett sequenziertes und gut annotiertes Genom besitzt. Ich konnte alle sieben Egfr-Liganden in Medaka identifizieren und konnte weiterhin zeigen, dass die zwei Teleost-spezifischen Egfr-Kopien dieses Fisches ein unterschiedliches Expressionsmuster in adulten Geweben aufweisen, welches außerdem mit unterschiedlicher Egfr-Liganden-Expression einherging. Diese Daten sprechen für eine Subfunktionalisierung der Egfr-Funktionen in Medaka. Unsere phylogenetischen und Syntenie-Analysen unterstützen die Hypothese, dass nur ein einziges Egfr-Liganden-Gen des Chordaten-Vorfahren der genetische Ursprung für die zahlreichen Egfr-Liganden-Gene, die in heutigen Vertrebraten zu finden sind, darstellt. Ich konnte weiterhin zeigen, dass die an der Ligandenbindung beteiligten Domänen des Egfr nicht zwischen Tetrapoden und Teleostiern konserviert sind. Diese Daten sprechen somit gegen die Verwendung heterologer Liganden in Zellkulturexperimenten mit Fischzellen. Trotz der gut verstandenen Konsequenzen einer Xmrk-Expression auf die Pigmentzelle lässt sich die Xmrk-vermittelte Melanomentstehung in Xiphophorus relativ schwer in vivo untersuchen. In unserem Labor wurde daher kürzlich ein neues Tiermodell für Melanome entwickelt. Dabei handelt es sich um einen mitf::xmrk-transgenen Medaka. Diese Fische exprimieren xmrk unter der Kontrolle des Pigmentzell-spezifischen Mitf-Promoters. Während meiner Doktorarbeit trug ich zur molekularen Analyse der stabil transgenen Tiere bei und konnte zeigen, dass die Xmrk-vermittelte Signalgebung in mitf::xmrk-Medakas der von Xmrk-exprimierenden Xiphophorus-Fischen gleicht. Diese Daten, zusammen mit weiteren RNA-Expressions-, Protein- und histologischen Analysen, zeigten, dass die Expression von xmrk unter der Kontrolle eines Pigmentzellspezifischen Promoters ausreichend für die Melanomentstehung in Medaka ist. Eine Besonderheit dieses Melanommodelles ist die auffallend stereotype Tumorentstehung. Der Beginn der Hyperpigmentierung wird bereits in frühen Larvenstadien sichtbar und führt – je nach Fischlinie – anschließend zuverlässig zu extrakutanen Pigmentzelltumoren oder invasiven bzw. uvealen Melanomen. Um eine potenzielle Funktion der Egfr-Liganden für Xmrk-induzierte Melanome zu untersuchen, machte ich mir zwei Modellsysteme zunutze. Eines der beiden Modelle war der bereits oben erwähnte mitf::xmrk-transgene Medaka, das andere war ein in-vitro- Zellkultursystem, bei dem die EGF-induzierbare Xmrk-Chimäre HERmrk stabil in murinen Melanozyten exprimiert wird. Hier konnte ich zeigen, dass HERmrk-Aktivierung zu einer starken Genexpression der EGFR-Liganden Amphiregulin (Areg) und Heparin-binding EGFlike growth factor (Hbegf) in Melanozyten führte. Diese Regulierung war abhängig von den MAPK- und SRC-Signalwegen. Weiterhin wurde eine Induktion von Adam10 und Adam17, den zwei bedeutsamsten Proteasen zur Freisetzung von EGFR-Liganden (“Sheddasen”), festgestellt. Ich konnte die Funktionalität der so sezernierten Liganden durch in-vitro- Experimente nachweisen. Anhand des mitf::xmrk Medaka-Modelles konnte ich ebenfalls zeigen, dass sowohl mehrere Egfr-Ligandengene, nämlich egf, areg, betacellulin (btc) und epigen (epgn), als auch egfrb in Tumoren von Medaka-Fischen mit metastatischen Melanomen heraufreguliert wurden. All diese Daten lassen auf einen durch Xmrk induzierten autokrinen EGFR-Liganden-Loop schließen. Interessanterweise zeigte sich durch in-vitro- Experimente mit konditioniertem Überstand von Medaka Egf- und Hbegf-produzierenden Zellen, dass nicht nur Xiphophorus Egfrb, sondern auch das bereits aktivierte Xmrk durch beide Liganden weiter stimuliert werden konnte. Zusammengefasst zeigen meine in-vitro- und in-vivo-Daten, dass Xmrk in der Lage ist, einen funktionalen autokrinen Egfr-Liganden-Loop zu induzieren. Dieses Ergebnis unterstreicht die Bedeutung autokriner Loops in Rezeptortyrosinkinasen (RTK)-abhängiger Tumorentstehung und zeigt auf, dass selbst die onkogene Signalgebung prädimerisierter RTKs durch Ligandenbindung verstärkt werden kann.
urn:nbn:de:bvb:20-opus-51369
5136
X123131
Deutsches Urheberrecht
Juliette Agnès Geneviève Claire Laisney
deu
swd
Schwertkärpfling
deu
swd
Melanom
deu
swd
Epidermaler Wachstumsfaktor-Rezeptor
eng
uncontrolled
cancer
eng
uncontrolled
melanoma
eng
uncontrolled
fish model
eng
uncontrolled
EGFR
Biowissenschaften; Biologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/4253/Thesis_J_Laisney_PDF.pdf
6740
2012
eng
doctoralthesis
1
2013-08-12
--
2013-08-01
Oncogene-induced senescence in melanocytes
Onkogen-induzierte Seneszenz in Melanozyten
Melanoma is the most aggressive skin cancer with very limited treatment options. Upon appearance of metastases chemotherapeutics are used to either kill or slow down the growth of cancer cells by inducing apoptosis or senescence, respectively. With melanomas originating from melanocytes, it is vital to elucidate the mechanisms that distinguish senescence induction from proliferation and tumourigenicity. Xmrk (Xiphophorus melanoma receptor kinase), the fish orthologue of the human epidermal growth factor receptor (EGFR), causes highly aggressive melanoma in fish. Using an inducible variant, HERmrk, I showed that high receptor levels result in melanocyte senescence, whereas low and medium expression allows for cell proliferation and tumourigenicity. Mechanistically, HERmrk leads to increased reactive oxygen species (ROS) levels, which trigger a DNA damage response. Consequently, multinucleated, senescent cells develop by both endomitosis and fusion. Furthermore, oncogenic N‐RAS (N-‐RAS61K) induces a similar multinucleated phenotype in melanocytes. In addition, I found that both overexpression of C‐MYC and the knockdown of miz‐1 (Myc‐interacting zinc finger protein 1) diminished HERmrk‐induced senescence entry. C‐MYC prevent ROS induction, DNA damage and senescence, while acting synergistically with HERmrk in conveying tumourigenic features to melanocytes. Further analyses identified cystathionase (CTH) as a novel target gene of Myc and Miz-1 crucial for senescence prevention. CTH encodes an enzyme involved in the synthesis of cysteine from methionine, thereby allowing for increased ROS detoxification. Even though senescence was thought to be irreversible and hence tumour protective, I demonstrated that prolonged expression of the melanoma oncogene N‐RAS61K in pigment cells overcomes initial OIS by triggering the emergence of tumour‐initiating, mononucleated stem‐like cells from multinucleated senescent cells. This progeny is dedifferentiated, highly proliferative, anoikis‐resistant and induces fast‐growing, metastatic tumours upon transplantation into nude mice. Our data demonstrate that induction of OIS is not only a cellular failsafe mechanism, but also carries the potential to provide a source for highly aggressive, tumour‐initiating cells.
Das Melanom ist der aggressivste Hautkrebstyp mit aeußerst begrenzten Therapiemoeglichkeiten. Sobald Metastasen diagnostiziert werden, kommen Chemotherapeutika zum Einsatz, deren Aufgabe darin besteht, die Krebszellen durch Apotoseinduktion zu toeten oder ihre Verbreitung mittels Seneszenz zu verlangsamen. Da Melanome aus Melanozyten hervorgehen, ist es essentiell, die Mechanismen zu analysieren, die entscheiden, ob Zellen seneszent oder tumorigen werden. Xmrk, die Xiphophorus‐Melanom‐Rezeptor‐Kinase und Fischortholog des humanen epidermalen Wachstumsfaktors (EGFR), verursacht aggressive Melanome in Fischen. Durch den Einsatz von HERmrk, einer induzierbaren Variante des Rezeptors, konnte ich zeigen, dass hohe Expressionslevel Seneszenz in Melanozyten zur Folge haben, wohingegen niedrige oder mittlere Rezeptorlevel mit erhöhter Zellproliferation und Tumorigenitaet der Zellen einhergehen. Mechanistisch gesehen, führt die Aktivierung von HERmrk zu gesteigerten Level an reaktiven Sauerstoffspezies (ROS), die wiederum DNA‐Schäden verursachen und dadurch bestimmte Signalwege auslösen. Durch Endomitose und Fusion entstehen letztendlich multinukleaere, seneszente Zellen. Interessanterweise, führte die Expression von onkogenem N‐RAS (N‐RAS61K) in Melanozyten zu einem sehr ähnlichen Phaenotyp. Des Weiteren konnte ich zeigen, dass sowohl die Überexpression von C-MYC als auch der Knockdown von miz‐1 (Myc‐interagierendes Zinkfingerprotein 1) der HERmrk-induzierten Seneszenz entgegenwirkten. C‐MYC verhindert einerseits die Entstehung von ROS, die dadurch verursachten DNA‐Schaeden und damit die Seneszenz und wirkt andererseits synergistisch mit HERmrk, indem es den Melanozyten tumorigene Eigenschaften verleiht. In weiteren Analysen wurde Cystathionase (CTH) als neues Zielgen von Myc und Miz-1 identifiziert, dem eine zentrale Rolle in der Seneszenzverhinderung zukommt. CTH kodiert fuer ein Enzym, das die Synthese von Cystein aus Methionin und damit die Entsorgung von ROS ermöglicht. Obwohl man davon ausgeht, dass Seneszenz einen irreversiblen Mechanismus darstellt, der die Tumorentstehung verhindert, konnte ich zeigen, dass die langfristige Expression des Melanomonkogens N‐RAS61K die initiale Seneszenzinduktion durchbricht. Dabei gehen mononukleaere, tumorigene, stammzellaehnliche Zellen aus seneszenten Zellen hervor. Diese Tochterzellen sind dedifferenziert, hochproliferativ, Anoikis‐resistent und induzieren schnellwachsende, metastasierende Tumoren in Nacktmaeusen. Damit machen meine Daten deutlich, dass Seneszenz nicht nur als zellulaerer Schadensbegrenzungsmechanismus fungiert, sondern auch das Potential hat, aeußerst aggressive Tumorzellen zu generieren.
urn:nbn:de:bvb:20-opus-79316
7931
X124677
Claudia Leikam
deu
swd
Melanom
deu
swd
Altern
deu
swd
Onkogen
deu
swd
Melanophor
deu
swd
Hautkrebs
deu
uncontrolled
Seneszenz
deu
uncontrolled
Xmrk
deu
uncontrolled
N-RAS
eng
uncontrolled
melanoma
eng
uncontrolled
senescence
eng
uncontrolled
OIS
eng
uncontrolled
skin cancer
eng
uncontrolled
oncogenes
Medizin und Gesundheit
open_access
Graduate School of Life Sciences
Universität Würzburg
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/6740/PhD_Claudia_Leikam_final_2_noCV_incl_dates.pdf
21543
2020
eng
928
939
5
183
article
1
--
--
--
GNAQ and GNA11 mutant nonuveal melanoma: a subtype distinct from both cutaneous and uveal melanoma
Background
GNAQ and GNA11 mutant nonuveal melanoma represent a poorly characterized rare subgroup of melanoma with a gene mutation profile similar to uveal melanoma.
Objectives
To characterize these tumours in terms of clinical behaviour and genetic characteristics.
Methods
Patients with nonuveal GNAQ/11 mutated melanoma were identified from the prospective multicentre tumour tissue registry ADOREG, Tissue Registry in Melanoma (TRIM) and additional cooperating skin cancer centres. Extensive data on patient, tumour and treatment characteristics were collected retrospectively. Targeted sequencing was used to determine tumour mutational burden. Immunohistochemistry staining was performed for programmed death‐ligand 1 and BRCA1‐associated protein (BAP)1. Existing whole‐exome cutaneous and uveal melanoma data were analysed for mutation type and burden.
Results
We identified 18 patients with metastatic GNAQ/11 mutant nonuveal melanoma. Tumours had a lower tumour mutational burden and fewer ultraviolet signature mutations than cutaneous melanomas. In addition to GNAQ and GNA11 mutations (nine each), six splicing factor 3b subunit 1 (SF3B1), three eukaryotic translation initiation factor 1A X‐linked (EIF1AX) and four BAP1 mutations were detected. In contrast to uveal melanoma, GNAQ/11 mutant nonuveal melanomas frequently metastasized lymphatically and concurrent EIF1AX, SF3B1 and BAP1 mutations showed no apparent association with patient prognosis. Objective response to immunotherapy was poor with only one partial response observed in 10 treated patients (10%).
Conclusions
Our findings suggest that GNAQ/11 mutant nonuveal melanomas are a subtype of melanoma that is both clinically and genetically distinct from cutaneous and uveal melanoma. As they respond poorly to available treatment regimens, novel effective therapeutic approaches for affected patients are urgently needed.
What is already known about this topic?
The rare occurrence of GNAQ/11 mutations in nonuveal melanoma has been documented.
GNAQ/11 mutant nonuveal melanomas also harbour genetic alterations in EIF1AX, SF3B1 and BAP1 that are of prognostic relevance in uveal melanoma.
What does this study add?
GNAQ/11 mutant nonuveal melanomas show metastatic spread reminiscent of cutaneous melanoma, but not uveal melanoma.
GNAQ/11 mutant nonuveal melanomas have a low tumour mutational burden that is higher than uveal melanoma, but lower than cutaneous melanoma.
What is the translational message?
Primary GNAQ/11 mutant nonuveal melanomas are a subtype of melanoma that is clinically and genetically distinct from both cutaneous and uveal melanoma.
As metastatic GNAQ/11 mutant nonuveal melanomas respond poorly to available systemic therapies, including immune checkpoint inhibition, novel therapeutic approaches for these tumours are urgently needed.
British Journal of Dermatology
10.1111/bjd.18947
urn:nbn:de:bvb:20-opus-215434
2020-11-02T11:35:38+00:00
sword
swordwue
attachment; filename=deposit.zip
3333d8341a89df181c5ce8a706a09923
British Journal of Dermatology 2020, 183(5):928–939. DOI: 10.1111/bjd.18947
false
true
CC BY-NC: Creative-Commons-Lizenz: Namensnennung, Nicht kommerziell 4.0 International
E. Livingstone
A. Zaremba
S. Horn
S. Ugurel
B. Casalini
M. Schlaak
J.C. Hassel
R. Herbst
J.S. Utikal
B. Weide
R. Gutzmer
F. Meier
C. Koelsche
E. Hadaschik
A. Sucker
H. Reis
S. Merkelbach‐Bruse
M. Siewert
F. Sahm
A. von Deimling
I. Cosgarea
L. Zimmer
D. Schadendorf
B. Schilling
K.G. Griewank
eng
uncontrolled
melanoma
eng
uncontrolled
GNAQ
eng
uncontrolled
GNA11
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/21543/bjd.18947.pdf
23958
2021
eng
10
13
article
1
--
2021-05-12
--
Factors influencing the adjuvant therapy decision: results of a real-world multicenter data analysis of 904 melanoma patients
Adjuvant treatment of melanoma patients with immune-checkpoint inhibition (ICI) and targeted therapy (TT) significantly improved recurrence-free survival. This study investigates the real-world situation of 904 patients from 13 German skin cancer centers with an indication for adjuvant treatment since the approval of adjuvant ICI and TT. From adjusted log-binomial regression models, we estimated relative risks for associations between various influence factors and treatment decisions (adjuvant therapy yes/no, TT vs. ICI in BRAF mutant patients). Of these patients, 76.9% (95% CI 74–80) opted for a systemic adjuvant treatment. The probability of starting an adjuvant treatment was 26% lower in patients >65 years (RR 0.74, 95% CI 68–80). The most common reasons against adjuvant treatment given by patients were age (29.4%, 95% CI 24–38), and fear of adverse events (21.1%, 95% CI 16–28) and impaired quality of life (11.9%, 95% CI 7–16). Of all BRAF-mutated patients who opted for adjuvant treatment, 52.9% (95% CI 47–59) decided for ICI. Treatment decision for TT or ICI was barely associated with age, gender and tumor stage, but with comorbidities and affiliated center. Shortly after their approval, adjuvant treatments have been well accepted by physicians and patients. Age plays a decisive role in the decision for adjuvant treatment, while pre-existing autoimmune disease and regional differences influence the choice between TT or ICI.
Cancers
2072-6694
10.3390/cancers13102319
urn:nbn:de:bvb:20-opus-239583
2021-06-11T13:00:27+00:00
sword
swordwue
attachment; filename=deposit.zip
7243a460afe95bdf3dec8fbcdb2dccfe
Cancers (2021) 13:10, 2319. https://doi.org/10.3390/cancers13102319
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Georg Lodde
Andrea Forschner
Jessica Hassel
Lena M. Wulfken
Friedegund Meier
Peter Mohr
Katharina Kähler
Bastian Schilling
Carmen Loquai
Carola Berking
Svea Hüning
Kerstin Schatton
Christoffer Gebhardt
Julia Eckardt
Ralf Gutzmer
Lydia Reinhardt
Valerie Glutsch
Ulrike Nikfarjam
Michael Erdmann
Andreas Stang
Bernd Kowall
Alexander Roesch
Selma Ugurel
Lisa Zimmer
Dirk Schadendorf
Elisabeth Livingstone
eng
uncontrolled
melanoma
eng
uncontrolled
adjuvant treatment
eng
uncontrolled
checkpoint blocker
eng
uncontrolled
targeted therapy
eng
uncontrolled
BRAF
eng
uncontrolled
PD-1
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/23958/cancers-13-02319-v2.pdf
12558
2015
eng
120
5
article
1
2016-01-26
--
--
Hypoxia independent drivers of melanoma angiogenesis
Tumor angiogenesis is a process which is traditionally regarded as the tumor’s response to low nutrient supply occurring under hypoxic conditions. However, hypoxia is not a pre-requisite for angiogenesis. The fact that even single tumor cells or small tumor cell aggregates are capable of attracting blood vessels reveals the early metastatic capability of tumor cells. This review sheds light on the hypoxia-independent mechanisms of tumor angiogenesis in melanoma.
Frontiers in Oncology
10.3389/fonc.2015.00102
urn:nbn:de:bvb:20-opus-125586
Frontiers in Oncology 5:102. doi: 10.3389/fonc.2015.00102
Svenja Meierjohann
eng
uncontrolled
melanoma
eng
uncontrolled
angiogenesis
eng
uncontrolled
hypoxia-independent
eng
uncontrolled
reactive oxygen species
eng
uncontrolled
NF-κB
Medizin und Gesundheit
open_access
Theodor-Boveri-Institut für Biowissenschaften
Förderzeitraum 2015
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/12558/Meierjohann_fonc-05-00102.pdf
6787
2013
eng
doctoralthesis
1
2013-09-30
--
2013-09-18
Transcriptional regulation of cancer genes in the Xiphophorus melanoma system
Transkriptionelle Regulation von Krebsgenen im Xiphophorus-Melanommodell
The Xiphophorus melanoma system is a useful animal model for the study of the genetic basis of tumor formation. The development of hereditary melanomas in interspecific hybrids of Xiphophorus is connected to pigment cell specific overexpression of the mutationally activated receptor tyrosine kinase Xmrk. In purebred fish the oncogenic function of xmrk is suppressed by the molecularly still unidentified locus R. The xmrk oncogene was generated by a gene duplication event from the Xiphophorus egfrb gene and thereby has acquired a new 5’ regulatory sequence, which has probably altered the transcriptional control of the oncogene. So far, the xmrk promoter region was still poorly characterized and the molecular mechanism by which R controls xmrk-induced melanoma formation in Xiphophorus still remained to be elucidated. To test the hypothesis that R controls melanoma development in Xiphophorus on the transcriptional level, the first aim of the thesis was to gain a deeper insight into the transcriptional regulation of the xmrk oncogene. To this end, a quantitative analysis of xmrk transcript levels in different Xiphophorus genotypes carrying either the highly tumorigenic xmrkB or the non-tumorigenic xmrkA allele was performed. I was able to demonstrate that expression of the tumorigenic xmrkB allele is strongly increased in malignant melanomas of R-free backcross hybrids compared to benign lesions, macromelanophore spots, and healthy skin. The expression level of the non-tumorigenic xmrkA allele, in contrast, is not influenced by the presence or absence of R. These findings strongly indicate that differential transcriptional regulation of the xmrk promoter triggers the tumorigenic potential of these xmrk alleles. To functionally characterize the xmrk promoter region, I established a luciferase assay using BAC clones containing the genomic regions where xmrk and egfrb are located for generation of reporter constructs. This approach showed for the first time a melanoma cell specific transcriptional activation of xmrkB by its flanking regions, thereby providing the first functional evidence that the xmrk oncogene is controlled by a pigment cell specific promoter region. Subsequent analysis of different deletion constructs of the xmrkB BAC reporter construct strongly indicated that the regulatory elements responsible for the tumor-inducing overexpression of xmrkB in melanoma cells are located within 67 kb upstream of the xmrk oncogene. Taken together, these data indicate that melanoma formation in Xiphophorus is regulated by a tight transcriptional control of the xmrk oncogene and that the R locus acts through this mechanism. As the identification of the R-encoded gene(s) is necessary to fully understand how melanoma formation in Xiphophorus is regulated, I furthermore searched for alternative R candidate genes in this study. To this end, three genes, which are located in the genomic region where R has been mapped, were evaluated for their potential to be a crucial constituent of the regulator locus R. Among these genes, I identified pdcd4a, the ortholog of the human tumor suppressor gene PDCD4, as promising new candidate, because this gene showed the expression pattern expected from the crucial tumor suppressor gene encoded at the R locus.
Fische der Gattung Xiphophorus sind ein gut etabliertes Modellsystem zur Analyse der genetischen Grundlagen der Tumorentwicklung. Die Entwicklung hereditärer Melanome in bestimmten interspezifischen Xiphophorus-Hybriden wird durch die pigmentzellspezifische Überexpression des Onkogens xmrk ausgelöst. Dieses Gen codiert für eine durch Mutationen aktivierte Rezeptortyrosinkinase. In den reinerbigen Elterntieren wird die onkogene Funktion von xmrk durch den Regulator-Locus R unterdrückt, welcher jedoch auf molekularer Ebene noch nicht identifiziert wurde. Das Onkogen xmrk ist durch eine Genduplikation aus dem Protoonkogen egfrb entstanden und hat dabei eine neue regulatorische 5‘ Region erhalten, welche mit hoher Wahrscheinlichkeit die transkriptionelle Regulation des Onkogens verändert hat. Die Promotorregion von xmrk war allerdings bisher nur unzureichend charakterisiert und der molekulare Mechanismus, durch den der R-Locus die xmrk-induzierte Melanomentwicklung kontrolliert, war noch weitgehend unbekannt. Um zu analysieren, ob der R-Locus die Melanomentwicklung in Xiphophorus auf transkriptioneller Ebene kontrolliert, war das erste Ziel dieser Arbeit die transkriptionelle Regulation des xmrk Onkogens genauer zu untersuchen. Zu diesem Zweck habe ich eine quantitative Analyse der xmrk Expressionslevel in Geweben verschiedener Xiphophorus-Genotypen durchgeführt, welche entweder das stark tumorigene xmrkB oder das nicht tumorigene xmrkA Allel besitzen. Ich konnte zeigen, dass im Vergleich zu benignen Läsionen, Macromelanophoren und gesunder Haut, die Expression des tumorigenen xmrkB Allels in den malignen Melanomen der R-defizienten Rückkreuzungshybride stark erhöht ist. Das Expressionslevel des xmrkA Allels wird hingegen nicht durch den R-Locus beeinflusst. Dieses Ergebnis deutet darauf hin, dass eine differenzielle transkriptionelle Regulierung des xmrk Promotors für die Unterschiede im onkogenen Potential dieser Allele verantwortlich ist. Um die xmrk Promotorregion funktional zu charakterisieren, habe ich in der hier vorliegenden Studie einen Luciferase-Assay etabliert, für den BAC-Klone, welche die xmrk- oder egfrb-Region enthalten, zur Herstellung von Reporterkonstrukten verwendet wurden. Mit Hilfe dieses Ansatzes konnte ich zum ersten Mal eine melanomzellspezifische Aktivierung des xmrkB Gens durch seine regulatorischen Regionen zeigen. Dies liefert den ersten funktionalen Beweis, dass das xmrk Onkogen tatsächlich durch einen pigmentzellspezifischen Promotor kontrolliert wird. Durch die nachfolgende Analyse einer Deletionsserie des xmrkB Reporterkonstrukts konnte gezeigt werden, dass die regulatorischen Elemente, welche die starke Überexpression von xmrk in Melanomzellen steuern, in den proximalen 67 kb der xmrk 5‘ Region lokalisiert sind. Zusammengefasst deuten diese Ergebnisse darauf hin, dass die Melanomentwicklung in Xiphophorus durch eine strikte transkriptionelle Kontrolle des xmrk Onkogens reguliert wird und dass der Regulator-Locus R seine tumorsuppressive Funktion über diesen Mechanismus ausübt. Da die Identifizierung des R-Locus-Gens entscheidend ist, um die Melanomentwicklung in Xiphophorus vollständig zu verstehen, habe ich im zweiten Teil dieser Arbeit drei Gene, welche in derselben genomischen Region liegen in der R lokalisiert wurde, genauer untersucht, um zu testen, ob es sich bei einem dieser Gene um eine entscheidende tumorsuppressive Komponente des R-Locus handelt. Von diesen Genen wurde pdcd4a, welches das Ortholog zum humanen Tumorsuppressorgen PDCD4 ist, als vielversprechendes neues Kandidatengen identifiziert, da das Expressionsmuster von pdcd4a mit dem zu erwartenden Expressionsmuster des am R-Locus codierten Tumorsuppressorgens übereinstimmt.
urn:nbn:de:bvb:20-opus-82319
8231
X124745
Deutsches Urheberrecht
Janine Regneri
deu
swd
Melanom
deu
swd
Schwertkärpfling
deu
swd
Chromatophor
deu
swd
Epidermaler Wachstumsfaktor
deu
swd
Onkogen
deu
uncontrolled
Tumorsuppressorgen
deu
uncontrolled
Hybrid
deu
uncontrolled
transkriptionelle Regulation
eng
uncontrolled
melanoma
eng
uncontrolled
Xiphophorus
eng
uncontrolled
xmrk
eng
uncontrolled
transcriptional control
eng
uncontrolled
pigment cell
deu
uncontrolled
Hautkrebs
deu
uncontrolled
Epidermaler Wachstumsfaktor-Rezeptor
Biowissenschaften; Biologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/6787/Dissertation_Janine_Regneri.pdf
2304
2007
eng
doctoralthesis
1
2008-03-27
--
2008-03-19
RAF Kinases: Pathway, Modulation and Modeling
RAF Kinase: Signalweg, Modulation und Modellierung
The Ras/RAF/MEK/ERK cascade is a central cellular signal transduction pathway involved in cell proliferation, differentiation, and survival where RAF kinases are pivotal kinases implicated in cancer. The development of specific irreversible kinase inhibitors is a rewarding but difficult aim. CI-1033 was developed to irreversibly inhibit erbB receptor tyrosine kinases by reacting to the Cys113 residue (p38alpha MAP kinase numbering) of the kinase domain. In this study we tried a similar approach to target the RAF oncoproteins which posses a similar cysteine at position 108 in the hinge region between the small n-lobe and the large c-lobe of the kinase domain. A novel synthetic approach including a lyophilization step allowed us the synthesis of a diphenyl urea compound with an epoxide moiety (compound 1). Compound 1 possessed inhibitory activity in vitro. However our time kinetics experiments and mass spectroscopic studies clearly indicate that compound 1 does not react covalently with the cysteine residue in the hinge region. Moreover, in cell culture experiments, a strong activation of the RAF signaling pathway was observed, an effect which is known from several other RAF kinase inhibitors and is here reported for the first time for a diphenyl urea compound, to which the clinically used unspecific kinase inhibitor BAY 43-9006 (Sorafinib, Nexavar) belongs. Although activation was apparently independent on B- and C-RAF hetero-oligomerization in vitro, in vivo experiments support such a mechanism as the activation did not occur in starved knockout cells lacking either B-RAF or C-RAF. Furthermore, we developed a mathematical model of the Ras/RAF/MEK/ERK cascade demonstrating how stimuli induce different signal patterns and thereby different cellular responses, depending on cell type and the ratio between B-RAF and C-RAF. Based on biochemical data for activation and dephosphorylation, we set up differential equations for a dynamical model of the Ras/RAF/MEK/ERK cascade. We find a different signaling pattern and response result for B-RAF (strong activation, sustained signal) and C-RAF (steep activation, transient signal). We further support the significance of such differential modulatory signaling by showing different RAF isoform expression in various cell lines and experimental testing of the predicted kinase activities in B-RAF, C-RAF as well as mutated versions. Additionally the effect of the tumor suppressor DiRas3 (also known as Noey2 or ARHI) on RAF signaling was studied. I could show that DiRas3 down-regulates the mitogenic pathway by inhibition of MEK, a basis for a refined model of the Ras/RAF/MEK/ERK cascade.
Die Ras/RAF/MEK/ERK Kaskade ist ein zentraler zellulärer Signalweg, der bei der Regulierung der Proliferation, Differenzierung und Überleben der Zelle eine entscheide Rolle spielt. Dabei kommt den RAF Kinasen eine Schlüsselrolle bei der Tumorgenese zu. Die Entwicklung von spezifischen irreversiblen Kinasehemmern stellt einen attraktiven, jedoch schwierigen Ansatz zur Tumorsupression dar. CI-1033 wurde erfolgreich mit dem Ziel entwickelt, ErbB-Rezeptor-Tyrosinkinasen irreversibel zu inhibieren, indem es kovalent mit dem Cys113 (p38alpha MAP Kinase Nummerierung) in der Kinase-Domäne reagiert. In dieser Arbeit wird ein vergleichbarer Ansatz gegen die RAF-Onkoproteine verfolgt, die einen analogen Cystein-Rest in der Position 108 aufweisen. Dieser ist in der Hinge-Region zwischen dem kleinen n-lobe und dem großen c-lobe der Kinase-Domäne lokalisiert. Ein neuer synthetischer Ansatz, der einen Lyophilisierungsschritt mit einschloss, erlaubte hierfür die Synthese einer Diphenylharnstoff-Verbindung mit einer Epoxidgruppe (Verbindung 1). Verbindung 1 zeigt in vitro tatsächlich eine inhibitorische Aktivität gegen RAF-Kinasen. Jedoch zeigen unsere zeitkinetischen Experimente, sowie unsere massenspektrometrischen Analysen, dass Verbindung 1 keine kovalente Bindung mit dem Cystein-Rest in der Hinge-Region bildet. Außerdem stellten wir in Zellkulturexperimenten eine starke Aktivierung des RAF-induzierten Signalweges fest; ein Effekt, der bereits für andere RAF-Kinase-Inhibitoren beschrieben wurde, jedoch hier erstmalig auch für eine Diphenylharnstoff-Verbindung, zu der auch BAY 43-9006 (Sarafinib, Nexavar) gehört. BAY 43-9006 ist ein unspezifischer, für die Behandlung von Krebs zugelassener, Kinase Inhibitor. Obwohl die Aktivierung in vitro scheinbar unabhängig von einer Heterooligomerisierung von B-RAF und C-RAF war, unterstützen in vivo Experimente einen solchen Mechanismus, da in gehungerten knockout Zellen, in denen B-RAF oder C-RAF fehlte, keine Aktivierung beobachtet werden konnte. Des Weiteren zeigten wir in einem mathematischen Modell, wie abhängig vom B-RAF/C-RAF-Verhältnis verschiedene Zellantworten durch unterschiedliche Stimuli induzierbar werden. Basierend auf biochemischen Daten über Aktivierung und Dephosphorylierung sowie auf den Differentialgleichungen unseres Rechenmodells fanden wir eine unterschiedliche Signalkinetik für B-RAF (starke Aktivierung, anhaltendes Signal) und C-RAF (schwache Aktivierung, transientes Signal). Die Bedeutung dieser differenzierten Signalmodifikation wurde auch durch unterschiedliche Expression der RAF Isoformen in verschiedenen Zelllinien und durch die experimentelle Messung der Kinaseaktivität von B- und C-RAF sowie mutierte Formen überprüft. Zusätzlich wurde der Effekt des Tumorsupressorproteins DiRas3 (auch bekannt als Noey2 oder ARHI) auf den RAF-Signalweg untersucht. Wir konnten zeigen, dass DiRas3 den mitogenen Signalweges durch Inhibierung der mitogen-aktivierten Proteinkinase Kinase (MEK) negativ reguliert, eine Basis für ein verfeinertes Modell der Ras/RAF/MEK/ERK Kaskade.
urn:nbn:de:bvb:20-opus-26953
2695
X121804
Armin Robubi
deu
swd
Systembiologie
deu
uncontrolled
RAf
deu
uncontrolled
BAY 43-9006
deu
uncontrolled
Sorafinib
deu
uncontrolled
Nexavar
deu
uncontrolled
DiRas3
deu
uncontrolled
Noey2
deu
uncontrolled
ARHI
deu
uncontrolled
Diphenylharnstoff
deu
uncontrolled
Krebs
deu
uncontrolled
Melanom
deu
uncontrolled
Kinase Inhibitor
eng
uncontrolled
RAF
eng
uncontrolled
BAY 43-9006
eng
uncontrolled
Sorafinib
eng
uncontrolled
Nexavar
eng
uncontrolled
DiRas3
eng
uncontrolled
Noey2
eng
uncontrolled
ARHI
eng
uncontrolled
diphenyl urea
eng
uncontrolled
cancer
eng
uncontrolled
melanoma
eng
uncontrolled
kinase inhibitor
Biowissenschaften; Biologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/2304/robubi_thesis.pdf
17181
2017
eng
2
12
article
1
2018-11-15
--
--
Ecto-5 ' -Nucleotidase CD73 (NT5E), vitamin D receptor and FGF23 gene polymorphisms may play a role in the development of calcific uremic arteriolopathy in dialysis patients - Data from the German Calciphylaxis Registry
Introduction: Calciphylaxis/calcific uremic arteriolopathy affects mainly end-stage kidney disease patients but is also associated with malignant disorders such as myeloma, melanoma and breast cancer. Genetic risk factors of calciphylaxis have never been studied before.
Methods: We investigated 10 target genes using a tagging SNP approach: the genes encoding CD73/ ecto-5'-nucleotidase (purinergic pathway), Matrix Gla protein, Fetuin A, Bone Gla protein, VKORC1 (all related to intrinsic calcification inhibition), calcium-sensing receptor, FGF23, Klotho, vitamin D receptor, stanniocalcin 1 (all related to CKD-MBD). 144 dialysis patients from the German calciphylaxis registry were compared with 370 dialysis patients without history of CUA. Genotyping was performed using iPLEX Gold MassARRAY(Sequenom, San Diego, USA), KASP genotyping chemistry (LGC, Teddington, Middlesex, UK) or sequencing. Statistical analysis comprised logistic regression analysis with adjustment for age and sex.
Results: 165 SNPs were finally analyzed and 6 SNPs were associated with higher probability for calciphylaxis (OR>1) in our cohort. Nine SNPs of three genes (CD73, FGF23 and Vitamin D receptor) reached nominal significance (p< 0.05), but did not reach statistical significance after correction for multiple testing. Of the CD73 gene, rs4431401 (OR = 1.71, 95%CI 1.08-2.17, p = 0.023) and rs9444348 (OR = 1.48, 95% CI 1.11-1.97, p = 0.008) were associated with a higher probability for CUA. Of the FGF23 and VDR genes, rs7310492, rs11063118, rs13312747 and rs17882106 were associated with a higher probability for CUA.
Conclusion: Polymorphisms in the genes encoding CD73, vitamin D receptor and FGF23 may play a role in calciphylaxis development. Although our study is the largest genetic study on calciphylaxis, it is limited by the low sample sizes. It therefore requires replication in other cohorts if available.
PLoS One
10.1371/journal.pone.0172407
28212442
urn:nbn:de:bvb:20-opus-171817
PLoS ONE (2017) 12(2): e0172407. https://doi.org/10.1371/journal.pone.0172407
true
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Hansjörg Rothe
Vincent Brandenburg
Margot Haun
Barbara Kollerits
Florian Kronenberg
Markus Ketteler
Christoph Wanner
eng
uncontrolled
single nucleotide polymorphisms
eng
uncontrolled
calcification
eng
uncontrolled
medical dialysis
eng
uncontrolled
genotyping
eng
uncontrolled
cancer risk factors
eng
uncontrolled
vitamin D
eng
uncontrolled
chronic kidney disease
eng
uncontrolled
melanoma
Medizin und Gesundheit
open_access
Medizinische Klinik und Poliklinik I
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/17181/Rothe_pone.0172407.pdf
21119
2020
eng
8
12
article
1
--
2020-08-17
--
Comparison of hydrogels for the development of well-defined 3D cancer models of breast cancer and melanoma
Bioprinting offers the opportunity to fabricate precise 3D tumor models to study tumor pathophysiology and progression. However, the choice of the bioink used is important. In this study, cell behavior was studied in three mechanically and biologically different hydrogels (alginate, alginate dialdehyde crosslinked with gelatin (ADA–GEL), and thiol-modified hyaluronan (HA-SH crosslinked with PEGDA)) with cells from breast cancer (MDA-MB-231 and MCF-7) and melanoma (Mel Im and MV3), by analyzing survival, growth, and the amount of metabolically active, living cells via WST-8 labeling. Material characteristics were analyzed by dynamic mechanical analysis. Cell lines revealed significantly increased cell numbers in low-percentage alginate and HA-SH from day 1 to 14, while only Mel Im also revealed an increase in ADA–GEL. MCF-7 showed a preference for 1% alginate. Melanoma cells tended to proliferate better in ADA–GEL and HA-SH than mammary carcinoma cells. In 1% alginate, breast cancer cells showed equally good proliferation compared to melanoma cell lines. A smaller area was colonized in high-percentage alginate-based hydrogels. Moreover, 3% alginate was the stiffest material, and 2.5% ADA–GEL was the softest material. The other hydrogels were in the same range in between. Therefore, cellular responses were not only stiffness-dependent. With 1% alginate and HA-SH, we identified matrices that enable proliferation of all tested tumor cell lines while maintaining expected tumor heterogeneity. By adapting hydrogels, differences could be accentuated. This opens up the possibility of understanding and analyzing tumor heterogeneity by biofabrication.
Cancers
2072-6694
10.3390/cancers12082320
urn:nbn:de:bvb:20-opus-211195
swordwue
2020-09-02T23:11:51+00:00
attachment; filename=deposit.zip
4c8076bd140fac357353c7daae2d553d
Cancers (2020) 12:8, 2320. https://doi.org/10.3390/cancers12082320
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Rafael Schmid
Sonja K. Schmidt
Jonas Hazur
Rainer Detsch
Evelyn Maurer
Aldo R. Boccaccini
Julia Hauptstein
Jörg Teßmar
Torsten Blunk
Stefan Schrüfer
Dirk W. Schubert
Raymund E. Horch
Anja K. Bosserhoff
Andreas Arkudas
Annika Kengelbach-Weigand
eng
uncontrolled
breast cancer
eng
uncontrolled
melanoma
eng
uncontrolled
biofabrication
eng
uncontrolled
hydrogel
eng
uncontrolled
tumor heterogeneity
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Unfall-, Hand-, Plastische und Wiederherstellungschirurgie (Chirurgische Klinik II)
Abteilung für Funktionswerkstoffe der Medizin und der Zahnheilkunde
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/21119/cancers-12-02320-v2.pdf
11146
2015
eng
doctoralthesis
1
2015-03-23
--
2015-03-11
Role of Peroxiredoxin 6 in human melanoma
Die Funktion von Peroxiredoxin 6 im humanen Melanom
Peroxiredoxin 6 (PRDX6) is a bifunctional enzyme comprising a peroxidase and a Ca2+-independent phospholipase (iPLA2) activity. This renders the enzyme capable of detoxifying reactive oxygen species (ROS) and of catalyzing the liberation of arachidonic acid (AA) from cellular membranes. Released AA can be further metabolized to bioactive lipids including eicosanoids, which are involved in inflammation, cell growth, differentiation, invasion and proliferation. Human melanoma cells are often characterized by imbalances in both ROS and lipid levels, which can be generated by oncogenic signaling, altered metabolism or UV irradiation.
In previous studies, a comparative proteome analysis of the Xiphophorus fish melanoma model revealed a strong upregulation of Prdx6 in benign and malignant lesions compared to healthy skin. As the Xiphophorus melanoma model displays in many respects molecular characteristics that are similar to human melanoma, I investigated the functional role of PRDX6 in human melanoma cells.
The first part of the study deals with the regulation of PRDX6 in melanocytes and human melanoma cells. I could demonstrate that the protein level of PRDX6 was strongly enhanced by the induction of the EGFR orthologue Xmrk from the Xiphophorus fish as well as the human EGFR. The upregulation of PRDX6 was further shown to be mediated in a PI3K-dependent and ROS-independent manner.
The main part of the thesis comprises the investigation of the functional role of PRDX6 in human melanoma cells as well as the analysis of the underlying mechanism. I could show that knockdown of PRDX6 enhanced the oxidative stress response and led to decreased proliferation of melanoma cells. This cell growth effect was mainly mediated by the iPLA2 activity of PRDX6. Under conditions of strongly enhanced oxidative stress, the peroxidase activity became also important for cellular proliferation. Furthermore, the anti-proliferative effect in cells with lowered PRDX6 levels was the result of reduced cellular AA content and the decrease in the activation of SRC family proteins. Similarly, supplementation with AA led to regeneration of SRC family kinase activity and to an improvement in the reduced proliferation after knockdown of PRDX6. Since AA can be further processed into the prostaglandin PGE2, which has a pro-tumorigenic function in some cancer types, I further examined whether this eicosanoid is involved in the proliferative function of PRDX6. In contrast to AA, PGE2 was not consistently required for melanoma proliferation.
In summary, I could demonstrate that PRDX6 plays a major role in AA-dependent lipid signaling in melanoma cells and thereby regulates proliferation. Interestingly, the proliferation relevant iPLA2 activity can be pharmacologically targeted, and melanoma cell growth was clearly blocked by the inhibitor BEL. Thus, I could identify the phospholipase activity of PRDX6 as a new therapeutically interesting target for melanoma treatment.
Peroxiredoxin 6 (PRDX6) ist ein bifunktionales Enzym, welches neben seiner Peroxidase-Aktivität auch eine Ca2+-unabhängige Phospholipase-Aktivität besitzt. Aufgrund dieser beiden Aktivitäten ist das Enzym in der Lage, sowohl oxidativen Stress zu bekämpfen als auch die Freisetzung von Arachidonsäure aus zellulären Membranen zu katalysieren. Freie Arachidonsäure (AA) dient der Generierung von bioaktiven Lipiden wie zum Beispiel Eicosanoiden, welche an Entzündungsreaktionen, Zellwachstum, Differenzierung, Invasion und Proliferation beteiligt sind. Humane Melanomzellen zeichnen sich oft durch ein gestörtes Gleichgewicht reaktiver Sauerstoffspezies und zellulärer Lipide aus. Dieses Ungleichgewicht kann durch onkogene Signalgebung, einen veränderten Metabolismus oder UV-Bestrahlung hervorgerufen werden.
Eine vorangegangene Proteomanalyse des Xiphophorus-Fisch-Melanommodells zeigte, dass im Vergleich zur gesunden Haut die Menge an PRDX6 in benignen und malignen Läsionen stark erhöht ist. Da das Xiphophorus-Melanommodell in vielerlei Hinsicht die molekulare Situation des humanen Melanoms wiederspiegelt, habe ich die funktionale Rolle von PRDX6 in humanen Melanomzellen untersucht.
Der erste Teil der Studie beschäftigt sich mit der Regulierung von PRDX6 in Melanozyten und humanen Melanomzellen. Ich konnte nachweisen, dass die Menge an PRDX6 Protein durch die Induktion des EGFR Orthologs Xmrk aus Xiphophorus Fischen, sowie des humanen EGFR stark erhöht wurde. Auch konnte ich zeigen, dass die Heraufregulierung von PRDX6 von der Signalgebung der PI3 Kinase, aber nicht von reaktiven Sauerstoffspezies abhängig war.
Der Hauptteil der vorliegenden Forschungsarbeit befasst sich mit der Ermittlung der funktionalen Rolle von PRDX6 in humanen Melanomzellen und der Analyse des zugrundeliegenden Mechanismus. Ich konnte nachweisen, dass ein Knockdown von PRDX6 die oxidative Stress-Antwort verstärkte und die Proliferation von Melanomzellen reduzierte. Der Effekt auf das zelluläre Wachstum wurde hierbei hauptsächlich durch die iPLA2-Aktivität von PRDX6 verursacht. Bei stark erhöhtem oxidativem Stress konnte auch eine Relevanz der Peroxidase-Aktivität für die zelluläre Proliferation nachgewiesen werden. Auch ging der anti-proliferative Effekt mit einer Abnahme zellulärer AA und der Reduktion aktiver Kinasen der SRC-Familie einher. Die Zugabe von AA zu Zellen mit PRDX6-Knockdown führte zur Regeneration der SRC-Kinase-Aktivität und konnte die Proliferation wieder verbessern. Da AA zum Prostaglandin PGE2 prozessiert werden kann, welches in einigen Krebsarten pro-tumorigene Funktionen erfüllt, untersuchte ich, ob dieses Eicosanoid auch für die proliferative Funktion von PRDX6 relevant ist. Im Gegensatz zu AA wies PGE2 jedoch keine kontinuierliche pro-proliferative Funktion auf.
Zusammenfassend konnte ich zeigen, dass PRDX6 eine entscheidende Rolle im AA- Stoffwechsel von Melanomzellen spielt und hierdurch die Proliferation reguliert. Interessanterweise ist die proliferationsrelevante iPLA2-Aktivität pharmakologisch hemmbar, und auch das Wachstum der Melanomzellen wurde durch den Inhibitor BEL deutlich inhibiert. Mit der Phospholipase-Aktivität von PRDX6 konnte ich somit einen neuen therapeutisch nutzbaren Angriffspunkt für das Melanom identifizieren.
urn:nbn:de:bvb:20-opus-111465
X 126468
Alexandra Schmitt
deu
swd
Melanom
deu
uncontrolled
Peroxiredoxin 6
eng
uncontrolled
peroxiredoxin 6
deu
uncontrolled
Melanom
eng
uncontrolled
melanoma
deu
uncontrolled
Arachidonsäure
eng
uncontrolled
arachidonic acid
deu
uncontrolled
Prostaglandin E2
eng
uncontrolled
prostaglandin E2
deu
uncontrolled
Melanomzellen
eng
uncontrolled
melanoma cells
deu
swd
Peroxiredoxin
deu
swd
Arachidonsäure
deu
swd
Prostaglandin E2
Biowissenschaften; Biologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/11146/Dissertation_Alexandra_Schmitt.pdf
12060
2014
eng
47
1
article
1
2015-10-21
--
--
STAT3 Single Nucleotide Polymorphism rs4796793 SNP Does Not Correlate with Response to Adjuvant IFNα Therapy in Stage III Melanoma Patients
Interferon alpha (IFNα) is approved for adjuvant treatment of stage III melanoma in Europe and the US. Its clinical efficacy, however, is restricted to a subpopulation of patients while side effects occur in most of treated patients. Thus, the identification of predictive biomarkers would be highly beneficial to improve the benefit to risk ratio. In this regard, STAT3 is important for signaling of the IFNα receptor. Moreover, the STAT3 single-nucleotide polymorphism (SNP) rs4796793 has recently been reported to be associated with IFNα sensitivity in metastatic renal cell carcinoma. To translate this notion to melanoma, we scrutinized the impact of rs4796793 functionally and clinically in this cancer. Interestingly, melanoma cells carrying the minor allele of rs4796793 were the most sensitive to IFNα in vitro. However, we did not detect a correlation between SNP genotype and STAT3 mRNA expression for either melanoma cells or for peripheral blood lymphocytes. Next, we analyzed the impact of rs4796793 on the clinical outcome of 259 stage III melanoma patients of which one-third had received adjuvant IFNα treatment. These analyses did not reveal a significant association between the STAT3 rs4796793 SNP and patients' progression free or overall survival when IFNα treated and untreated patients were compared. In conclusion, STAT3 rs4796793 SNP is no predictive marker for the efficacy of adjuvant IFNα treatment in melanoma patients.
Frontiers in Medicine
10.3389/fmed.2014.00047
2296-858X
25593920
urn:nbn:de:bvb:20-opus-120602
Frontiers in Medicine 1:47. doi: 10.3389/fmed.2014.00047
David Schrama
Selma Ugurel
Antje Sucker
Cathrin Ritter
Marc Zapatka
Dirk Schadendorf
Jürgen Christian Becker
eng
uncontrolled
predictive marker
eng
uncontrolled
single nucleotide polymorphism
eng
uncontrolled
melanoma
eng
uncontrolled
interferon
eng
uncontrolled
STAT3
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/12060/106_Schrama_Frontiers_in_Medicine.pdf
31840
2022
eng
283
284
3
187
article
1
--
--
--
How representative are data from global trials on programmed death-1 blockade in melanoma?
The British Journal of Dermatology
10.1111/bjd.21621
urn:nbn:de:bvb:20-opus-318406
@articleSchummer.2022, author = Schummer, Patrick and Schilling, Bastian, year = 2022, title = How representative are data from global trials on programmed death-1 blockade in melanoma?, pages = 283–284, volume = 187, number = 3, journal = The British journal of dermatology, doi = 10.1111/bjd.21621,
md5:c2f84c2f27c04a325c00f8fa65b6f979
2023-06-06T13:36:06+00:00
/tmp/php1lzkKJ
bibtex
647f364608ee77.52690593
The British Journal of Dermatology 2022, 187(3):283-284. DOI: 10.1111/bjd.21621
false
true
CC BY-NC-ND: Creative-Commons-Lizenz: Namensnennung, Nicht kommerziell, Keine Bearbeitungen 4.0 International
Patrick Schummer
Bastian Schilling
eng
uncontrolled
programmed cell death receptor-1
eng
uncontrolled
melanoma
eng
uncontrolled
therapy
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/31840/Schummer_British.pdf
12683
2012
eng
3456-3461
5
29
article
1
2016-02-10
--
--
Association between HRAS rs12628 and rs112587690 polymorphisms with the risk of melanoma in the North American population
HRAS belongs to the RAS genes superfamily. RAS genes are important players in several human tumors and the single-nucleotide polymorphism rs12628 has been shown to contribute to the risk of bladder, colon, gastrointestinal, oral, and thyroid carcinoma. We hypothesized that this SNP may affect the risk of cutaneous melanoma as well. HRAS gene contains a polymorphic region (rs112587690), a repeated hexanucleotide -GGGCCT- located in intron 1. Three alleles of this region, P1, P2, and P3, have been identified that contain two, three, and four repeats of the hexanucleotide, respectively. We investigated the clinical impact of these polymorphisms in a case–control study. A total of 141 melanoma patients and 118 healthy donors from the North America Caucasian population were screened for rs12628 and rs112587690 polymorphisms. Genotypes were assessed by capillary sequencing or fragment analysis, respectively, and rs12628 CC and rs112587690 P1P1 genotypes significantly associated with increased melanoma risk (OR = 3.83, p = 0.003; OR = 11.3, p = 0.033, respectively), while rs112587690 P1P3 frequency resulted significantly higher in the control group (OR = 0.5, p = 0.017). These results suggest that rs12628 C homozygosis may be considered a potential risk factor for melanoma development in the North American population possibly through the linkage to rs112587690.
Medical Oncology
dx.doi.org/10.1007/s12032-012-0255-3
urn:nbn:de:bvb:20-opus-126834
Medical Oncology (2012) 29:3456–3461 DOI 10.1007/s12032-012-0255-3
Sara Tomei
Sharon Adams
Lorenzo Uccellini
Davide Bedognetti
Valeria De Giorgi
Narnygerel Erdenebileg
Maria Libera Ascierto
Jennifer Reinboth
Qiuzhen Liu
Generoso Bevilacqua
Ena Wang
Chiara Mazzanti
Francesco M. Marincola
eng
uncontrolled
HRAS
eng
uncontrolled
polymorphism
eng
uncontrolled
melanoma
eng
uncontrolled
rs12628
eng
uncontrolled
rs112587690
Medizin und Gesundheit
open_access
Theodor-Boveri-Institut für Biowissenschaften
Lehrstuhl für Biochemie
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/12683/Tomei_Medical_Oncology.pdf
27513
2022
eng
9
14
article
1
--
2022-05-04
--
Blood eosinophils are associated with efficacy of targeted therapy in patients with advanced melanoma
Background: Eosinophils appear to contribute to the efficacy of immunotherapy and their frequency was suggested as a predictive biomarker. Whether this observation could be transferred to patients treated with targeted therapy remains unknown. Methods: Blood and serum samples of healthy controls and 216 patients with advanced melanoma were prospectively and retrospectively collected. Freshly isolated eosinophils were phenotypically characterized by flow cytometry and co-cultured in vitro with melanoma cells to assess cytotoxicity. Soluble serum markers and peripheral blood counts were used for correlative studies. Results: Eosinophil-mediated cytotoxicity towards melanoma cells, as well as phenotypic characteristics, were similar when comparing healthy donors and patients. However, high relative pre-treatment eosinophil counts were significantly associated with response to MAPKi (p = 0.013). Eosinophil-mediated cytotoxicity towards melanoma cells is dose-dependent and requires proximity of eosinophils and their target in vitro. Treatment with targeted therapy in the presence of eosinophils results in an additive tumoricidal effect. Additionally, melanoma cells affected eosinophil phenotype upon co-culture. Conclusion: High pre-treatment eosinophil counts in advanced melanoma patients were associated with a significantly improved response to MAPKi. Functionally, eosinophils show potent cytotoxicity towards melanoma cells, which can be reinforced by MAPKi. Further studies are needed to unravel the molecular mechanisms of our observations.
Cancers
2072-6694
10.3390/cancers14092294
urn:nbn:de:bvb:20-opus-275137
2022-06-05T20:26:54+00:00
sword
swordwue
attachment; filename=deposit.zip
3320d4cc0c5f2e6a859373a0e76492bc
Cancers (2022) 14:9, 2294. doi:10.3390/cancers14092294
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Simone Wendlinger
Jonas Wohlfarth
Sophia Kreft
Claudia Siedel
Teresa Kilian
Ulrich Dischinger
Markus V. Heppt
Kilian Wistuba-Hamprecht
Friedegund Meier
Matthias Goebeler
Dirk Schadendorf
Anja Gesierich
Corinna Kosnopfel
Bastian Schilling
eng
uncontrolled
melanoma
eng
uncontrolled
eosinophils
eng
uncontrolled
biomarker
Medizin und Gesundheit
open_access
Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie
Medizinische Klinik und Poliklinik I
Import
Förderzeitraum 2022
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/27513/cancers-14-02294-v2.pdf
5364
1992
eng
article
1
2011-12-09
--
--
Xmrk receptor tyrosine kinase is activated in Xiphophorus malignant melanoma
Xmrk encodes a putative transmembrane glycoprotein of the tyrosine kinase family and is a melanoma-inducing gene in Xiphophorus. We attempted to investigate the biological function of the putative Xmrk receptor by characterizing its signalling properties. Since a potential Iigand for Xmrk has not yet been identified, it has been difficult to analyse the biochemical properlies and biological function of this cell surface protein. In an approach towards such analyses, the Xmrk extracellular domain was replaced by the closely related Iigand-binding domain sequences of the human epidennal growth factor receptor (HER) and the ligand-induced activity of the chimeric HER-Xmrk proteinwas examined. We show that the Xmrk protein is a functional receptor tyrosine kinase, is highly active in malignant melanoma and displays a constitutive autophosphorylation activity possibly due to an activating mutation in its extracellular or transmembrane domain. In the focus formation assay the HER-Xmrk chimera is a potent transfonning protein equivalent to other tyrosine kinase oncoproteins.
urn:nbn:de:bvb:20-opus-61699
6169
In: Embo Journal (1992) , 11, 4239-4246
Deutsches Urheberrecht
Joachim Wittbrodt
Reiner Lammers
Barbara Malitschek
Axel Ullrich
Manfred Schartl
deu
swd
Physiologische Chemie
eng
uncontrolled
chimeric RTKs
eng
uncontrolled
melanoma
eng
uncontrolled
RTK
eng
uncontrolled
Xiphophorus
Chemie und zugeordnete Wissenschaften
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/5364/Schartl20.pdf