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Extracellular vesicles (EVs) are important mediators in the intercellular communication, influencing the function and phenotype of different cell types within the tumor micro-milieu and thus promote tumor progression. Since EVs safely transport packages of proteins, lipids and also nucleic acids such as miRNAs, EVs and their cargo can serve as diagnostic and prognostic markers. Therefore, the aim of this study was to investigate EV embedded miRNAs specific for melanoma, which could serve as potential biomarkers. In contrast to previous studies, we not only analysed miRNAs from EVs, but also included the miRNA profiles from the EV-secreting cells to identify candidates as suitable biomarkers. While the characterization of EVs derived from normal melanocytes and melanoma cells showed largely comparable properties with regard to size distribution and expression of protein markers, the NGS analyses yielded marked differences for several miRNAs. While miRNA load of EVs derived from normal human epidermal melanocytes (NHEMs) and melanoma cells were very similar, they were highly different from their secreting cells. By comprehensive analyses, six miRNAs were identified to be enriched in both melanoma cells and melanoma cell-derived EVs. Of those, the accumulation of miR-92b-3p, miR-182-5p and miR-183-5p in EVs could be validated in vitro. By functional network generation and pathway enrichment analysis we revealed an association with different tumor entities and signaling pathways contributing melanoma progression. Furthermore, we found that miR-92b-3p, miR-182-5p and miR-183-5p were also enriched in EVs derived from serum of melanoma patients. Our results support the hypothesis that miRNAs derived from EVs can serve as prognostic or diagnostic liquid biopsy markers in melanoma. We identified EV-derived miRNAs and showed that those miRNAs, which were enriched in melanoma cells and EVs, are also found elevated in serum-derived EVs of patients with metastatic melanoma, but not in healthy subjects.

Simple Summary Approximately 60% of all melanomas are associated with a constitutive activating BRAF mutation. Inhibition of BRAF downstream signaling by targeted therapies significantly improved patient outcomes. However, most patients eventually develop resistance. Here we identified miR-129-5p as a novel tumor suppressor in BRAF mutated melanoma, which expression is increased during response to BRAF inhibition, but repressed in an EZH2 dependent manner during activated BRAF signaling. Overexpression of miR-129-5p decreases melanoma cell proliferation and improves response to BRAF inhibition by targeting SOX4. Taken together our results emphasize SOX4 as a potential therapeutic target in BRAF driven melanoma which could be attacked by pharmaceutically. Abstract Many melanomas are associated with activating BRAF mutation. Targeted therapies by inhibitors of BRAF and MEK (BRAFi, MEKi) show marked antitumor response, but become limited by drug resistance. The mechanisms for this are not fully revealed, but include miRNA. Wishing to improve efficacy of BRAFi and knowing that certain miRNAs are linked to resistance to BRAFi, we wanted to focus on miRNAs exclusively associated with response to BRAFi. We found increased expression of miR-129-5p during BRAFi treatment of BRAF- mutant melanoma cells. Parallel to emergence of resistance we observed mir-129-5p expression to become suppressed by BRAF/EZH2 signaling. In functional analyses we revealed that miR-129-5p acts as a tumor suppressor as its overexpression decreased cell proliferation, improved treatment response and reduced viability of BRAFi resistant melanoma cells. By protein expression analyses and luciferase reporter assays we confirmed SOX4 as a direct target of mir-129-5p. Thus, modulation of the miR-129-5p-SOX4 axis could serve as a promising novel strategy to improve response to BRAFi in melanoma.

Sexuelle Zustimmung und Einvernehmlichkeit sind bisher keine zentralen Themen sexueller Bildung. Die vorliegende Publikation setzt bei dieser Leerstelle an und stellt theoretische, pädagogische und künstlerische Zugänge zur Auseinandersetzung mit sexueller Einvernehmlichkeit in Schule, Lehrer:innenbildung und außerschulischer Bildungsarbeit vor. Gegenwärtige Debatten um sexualisierte Übergriffe und Gewalt betonen insbesondere die Notwendigkeit von Präventions- und Interventionsarbeit. Der vorliegende Band geht darüber hinaus, indem er die Frage nach der Gestaltung von Einvernehmlichkeit als wichtigen Aspekt sexueller Selbstbestimmung ins Zentrum rückt. Die Beitragenden des Sammelbandes forschen nach Zugängen, die konsensuale, grenzwahrende und kooperative Begegnungsformen im Bereich des Sexuellen stärken. Über theoretische Texte, Gespräche, Filmanalysen, kunst- und sexualpädagogische Methoden sowie künstlerische Beiträge werden Möglichkeiten aufgezeigt, sexuelle Einvernehmlichkeit im Rahmen sexueller Bildung zu thematisieren. Die kunst- und sexualpädagogischen Konzepte legen den Schwerpunkt auf die Arbeit mit bewegte Bildern wie Coming-of-Age-Filme und Erklärvideos, anhand derer Auseinandersetzungen mit Fragen der Aushandlung und Entscheidungsfindung in sexuellen Interaktionen und intimen Beziehungen angeregt werden können.