Correction to: Eight years after an international workshop on myotonic dystrophy patient registries: Case study of a global collaboration for a rare disease (Orphanet Journal of Rare Diseases (2018) 13 (155) DOI: 10.1186/s13023-018-0889-0)

The original version of this article [1] unfortunately included an error to an author\u27s name. Author Jordi Díaz-Manera was erroneously presented as Jorge Alberto Diaz Manera. The correct author name has been included in the author list of this Correction article. For citation purposes the author\u27s given name is Jordi and family name Diaz-Manera. Therefore, the correct citation of the author\u27s details is: Diaz-Manera J

Pax3 Down-regulation and Shut-off of Melanogenesis in Melanoma B16/F10.9 by Interleukin-6 Receptor Signaling

International audienceThe microphthalmia-associated transcription factor (Mitf) is essential for melanocytic lineage development and for expression of melanogenic enzymes, such as tyrosinase. Interleukin-6 receptor/interleukin-6 chimera (IL6RIL6) induces in B16/F10.9 melanoma cells a loss of melanogenesis preceded by a sharp decrease in Mitf mRNA and gene promoter activity. In the Mitf promoter, the main cis-acting element mediating the IL6RIL6 effect is shown to be the binding site of Pax3, a paired homeodomain factor regulating among other things the development of melanocytes. Pax3 protein and mRNA levels decline steadily after IL6RIL6 treatment, and overexpression of an ectopic Pax3 cDNA suppresses the Mitf promoter inhibition. Loss of the synergism between Pax3 and Sox10, a high mobility group domain costimulatory factor, seems to be critical in the rapid decrease in Mitf gene expression. The Pax3 down-regulation in IL6RIL6-induced F10.9 cell is linked to growth arrest and transdifferentiation to a glial cell phenotype. IL6RIL6 stimulates the interleukin-6 family cytokine receptor gp130, leading to the rapid phosphorylation of Stat3 on tyrosine 705. This phosphorylation is required for Pax3 down-regulation and Mitf promoter silencing since these are inhibited in F10.9 cells overexpressing the Stat3 DN-mutant Y705F

CONSTITUTIVE ERK ACTIVITY INDUCES DOWN-REGULATION OF TRISTETRAPROLIN, A MAJOR PROTEIN CONTROLLING INTERLEUKIN8/CXCL8 mRNA STABILITY IN MELANOMA CELLS.

International audienceMost melanoma cells are characterized by the V600E mutation in B-Raf kinase. This mutation leads to increased expression of Interleukin (CXCL8) which plays a key role in cell growth and angiogenesis. Thus, CXCL8 appears to be an interesting therapeutic target. Hence, we performed vaccination of mice with GST-CXCL8 which results in a reduced incidence of syngenic B16 melanoma cell xenograft tumors. We next addressed the molecular mechanisms responsible for aberrant CXCL8 expression in melanoma. The CXCL8 mRNA contains multiples AU-rich sequences (AREs) that modulate mRNA stability through the binding of Tristetraprolin (TTP). Melanoma cell lines express very low TTP levels. We therefore hypothesized that the very low endogenous levels of TTP present in different melanoma cell lines might be responsible for the relative stability of CXCL8 mRNAs. We show that TTP is actively degraded by the proteasome and that ERK inhibition results in TTP accumulation. Conditional expression of TTP in A375 melanoma cells leads to CXCL8 mRNA destabilization via its 3'UTR and TTP over-expression reduces its production. In contrast, down-regulation of TTP by sh-RNA results in up-regulation of CXCL8 mRNA. Maintaining high TTP levels in melanoma cells decreases cell proliferation and autophagy and induces apoptosis. Sorafenib, a therapeutic agent targeting Raf kinases, decreases CXCL8 expression in melanoma cells through re-expression of TTP. We conclude that loss of TTP represents a key event in the establishment of melanomas through constitutive expression of CXCL8, which constitutes a potent therapeutic target

Inhibition of nicotinamide phosphoribosyltransferase reduces neutrophil-mediated injury in myocardial infarction

Aims: nicotinamide phosphoribosyltransferase (Nampt) is a key enzyme for nicotinamide adenine dinucleotide (NAD(+)) biosynthesis, and recent evidence indicates its role in inflammatory processes. Here, we investigated the potential effects of pharmacological Nampt inhibition with FK866 in a mouse myocardial ischemia/reperfusion model. In vivo and ex vivo mouse myocardial ischemia/reperfusion procedures were performed. Results: treatment with FK866 reduced myocardial infarct size, neutrophil infiltration, and reactive oxygen species (ROS) generation within infarcted hearts in vivo in a mouse model of ischemia and reperfusion. The benefit of FK866 was not shown in the Langendorff model (ex vivo model of working heart without circulating leukocytes), suggesting a direct involvement of these cells in cardiac injury. Sera from FK866-treated mice showed reduced circulating levels of the neutrophil chemoattractant CXCL2 and impaired capacity to prime migration of these cells in vitro. The release of CXCL8 (human homolog of murine chemokine CXCL2) by human peripheral blood mononuclear cells (PBMCs) and Jurkat cells was also reduced by FK866, as well as by sirtuin (SIRT) inhibitors and SIRT6 silencing, implying a pivotal role for this NAD(+)-dependent deacetylase in the production of this chemokine. Innovation: the pharmacological inhibition of Nampt might represent an effective approach to reduce neutrophilic inflammation- and oxidative stress-mediated tissue damage in early phases of reperfusion after a myocardial infarction. Conclusions: nampt inhibition appears as a new strategy to dampen CXCL2-induced neutrophil recruitment and thereby reduce neutrophil-mediated tissue injury in mice

Autophagy plays a critical role in the degradation of active RHOA, the control of cell cytokinesis, and genomic stability.

International audienceDegradation of signaling proteins is one of the most powerful tumor-suppressive mechanisms by which a cell can control its own growth. Here, we identify RHOA as the molecular target by which autophagy maintains genomic stability. Specifically, inhibition of autophagosome degradation by the loss of the v-ATPase a3 (TCIRG1) subunit is sufficient to induce aneuploidy. Underlying this phenotype, active RHOA is sequestered via p62 (SQSTM1) within autolysosomes and fails to localize to the plasma membrane or to the spindle midbody. Conversely, inhibition of autophagosome formation by ATG5 shRNA dramatically increases localization of active RHOA at the midbody, followed by diffusion to the flanking zones. As a result, all of the approaches we examined that compromise autophagy (irrespective of the defect: autophagosome formation, sequestration, or degradation) drive cytokinesis failure, multinucleation, and aneuploidy, processes that directly have an impact upon cancer progression. Consistently, we report a positive correlation between autophagy defects and the higher expression of RHOA in human lung carcinoma. We therefore propose that autophagy may act, in part, as a safeguard mechanism that degrades and thereby maintains the appropriate level of active RHOA at the midbody for faithful completion of cytokinesis and genome inheritance

Inhibition of nicotinamide phosphoribosyltransferase reduces neutrophil-mediated injury in myocardial infarction

Nicotinamide phosphoribosyltransferase (Nampt) is a key enzyme for nicotinamide adenine dinucleotide (NAD(+)) biosynthesis, and recent evidence indicates its role in inflammatory processes. Here, we investigated the potential effects of pharmacological Nampt inhibition with FK866 in a mouse myocardial ischemia/reperfusion model. In vivo and ex vivo mouse myocardial ischemia/reperfusion procedures were performed