TY - JOUR A1 - Kosnopfel, Corinna A1 - Sinnberg, Tobias A1 - Sauer, Birgit A1 - Niessner, Heike A1 - Muenchow, Alina A1 - Fehrenbacher, Birgit A1 - Schaller, Martin A1 - Mertens, Peter R. A1 - Garbe, Claus A1 - Thakur, Basant Kumar A1 - Schittek, Birgit T1 - Tumour progression stage-dependent secretion of YB-1 stimulates melanoma cell migration and invasion JF - Cancers N2 - 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. KW - melanoma KW - secretion KW - Y-box binding protein 1 KW - migration and invasiveness Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-211206 SN - 2072-6694 VL - 12 IS - 8 ER - TY - JOUR A1 - Allert, Stefanie A1 - Förster, Toni M. A1 - Svensson, Carl-Magnus A1 - Richardson, Jonathan P. A1 - Pawlik, Tony A1 - Hebecker, Betty A1 - Rudolphi, Sven A1 - Juraschitz, Marc A1 - Schaller, Martin A1 - Blagojevic, Mariana A1 - Morschhäuser, Joachim A1 - Figge, Marc Thilo A1 - Jacobsen, Ilse D. A1 - Naglik, Julian R. A1 - Kasper, Lydia A1 - Mogavero, Selene A1 - Hube, Bernhard T1 - \(Candida\) \(albicans\)-Induced Epithelial Damage Mediates Translocation through Intestinal Barriers JF - mBio N2 - Life-threatening systemic infections often occur due to the translocation of pathogens across the gut barrier and into the bloodstream. While the microbial and host mechanisms permitting bacterial gut translocation are well characterized, these mechanisms are still unclear for fungal pathogens such as Candida albicans, a leading cause of nosocomial fungal bloodstream infections. In this study, we dissected the cellular mechanisms of translocation of C. albicans across intestinal epithelia in vitro and identified fungal genes associated with this process. We show that fungal translocation is a dynamic process initiated by invasion and followed by cellular damage and loss of epithelial integrity. A screen of >2,000 C. albicans deletion mutants identified genes required for cellular damage of and translocation across enterocytes. Correlation analysis suggests that hypha formation, barrier damage above a minimum threshold level, and a decreased epithelial integrity are required for efficient fungal translocation. Translocation occurs predominantly via a transcellular route, which is associated with fungus-induced necrotic epithelial damage, but not apoptotic cell death. The cytolytic peptide toxin of C. albicans, candidalysin, was found to be essential for damage of enterocytes and was a key factor in subsequent fungal translocation, suggesting that transcellular translocation of C. albicans through intestinal layers is mediated by candidalysin. However, fungal invasion and low-level translocation can also occur via non-transcellular routes in a candidalysin-independent manner. This is the first study showing translocation of a human-pathogenic fungus across the intestinal barrier being mediated by a peptide toxin. IMPORTANCE Candida albicans, usually a harmless fungus colonizing human mucosae, can cause lethal bloodstream infections when it manages to translocate across the intestinal epithelium. This can result from antibiotic treatment, immune dysfunction, or intestinal damage (e.g., during surgery). However, fungal processes may also contribute. In this study, we investigated the translocation process of C. albicans using in vitro cell culture models. Translocation occurs as a stepwise process starting with invasion, followed by epithelial damage and loss of epithelial integrity. The ability to secrete candidalysin, a peptide toxin deriving from the hyphal protein Ece1, is key: C. albicans hyphae, secreting candidalysin, take advantage of a necrotic weakened epithelium to translocate through the intestinal layer. KW - Candida albicans KW - candidalysin KW - host cell damage KW - host cell invasion KW - intestinal barrier KW - necrosis KW - translocation Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-221084 VL - 9 IS - 3 ER -