Exosomes in melanoma: A role in tumor progression, metastasis and impaired immune system activity

Exosomes (Exo) are small vesicles produced by melanoma cells and the accessory cells of the tumor microenvironment. They emerge via both classical and direct pathways and actively participate in tumor colonisation of distant tissues. The proteins, nucleic acids, cytokines and growth factors engulfed by Exo are transferred to recipient cells, where they drive numerous functions required for the tumor escape from immune system control and tumor progression. By positively or negatively modulating immune cell properties, Exo provoke immune suppression and, in turn, defective dendritic cell (DC) functions. Together, these effects limit the cytotoxicity of T-cells and expand both T-regulatory and myeloid-derived suppressor populations. They also hinder perforin and granzyme production by natural killer cells. Finally, Exo also control the organotropism of melanoma cells. The distinct phenotypic properties of Exo can be exploited both for diagnostic purposes and in the early identification of melanoma patients likely to respond to immunotherapy. The potential therapeutic application of Exo derived from DCs has been demonstrated in vaccination trials, which showed an increase in anti-melanoma activity with respect to circulating tumor cells. However, additional studies are required before Exo can be effectively used in diagnostic and therapeutic applications in melanoma

CORRIGENDUM to The mechanisms of acute interstitial nephritis in the era of immune checkpoint inhibitors in melanoma

In this article, the authors’ first names and surnames were incorrectly listed in the wrong order. The correct author list is: Marco Tucci, Anna Passarelli, Annalisa Todisco, Francesco Mannavola, Luigia Stefania Stucci, Stella D’Oronzo, Michele Rossini, Marco Taurisano, Loreto Gesualdo and Franco Silvestris

AN OVERVIEW OF NATIONAL STUDIES ON THE ACQUISITION OF NAMING IN PROCEDURES WITH STIMULUS EQUIVALENCE AND COCHLEAR IMPLANT USERS

O presente artigo teve por objetivo descrever e analisar, criticamente, o conjunto de experimentos conduzidos por pesquisadores brasileiros a respeito de equivalência de estímulos, nomeação e implante coclear, publicados entre 2008 e 2013. Para tanto, realizou-se um levantamento bibliográfico, em periódicos da área da análise do comportamento e em bancos de teses e dissertações, selecionando-se trabalhos sobre equivalência de estímulos, implante coclear e nomeação. Foram analisados 11 estudos. Após a análise dos estudos, tornou-se possível sugerir que os procedimentos de ensino, comumente aplicados em participantes com implante coclear, foram mais eficientes para estabelecer comportamentos de seleção de figuras e de palavras impressas – ambos considerados repertório receptivo –, do que para estabelecer comportamentos de nomeação de figuras e de palavras impressas, que são comportamentos associados à leitura expressiva. Nesta perspectiva, percebe-se como são necessários avanços tecnológicos nos procedimentos de ensino que se propõem a instalar e manter comportamentos associados à leitura expressiva, a ponto de serem tão eficazes quanto os procedimentos de ensino que instalam e mantêm o repertório receptivo. Palavras chave: equivalência de estímulos, implante coclear, nomeação.This paper aims to describe and critically analyze the set of experiments conducted by Brazilian researchers on stimulus equivalence, naming (expressive repertoire) and cochlear implants, which were published between 2008 and 2013. To this end, a literature review in journals of Behavior Analysis, and banks of theses and dissertations, selecting work on stimulus equivalence, cochlear implants and naming, was conducted. 11 studies were analyzed. After analyzing the studies, it was possible to suggest that the teaching procedures, more often used with participants with cochlear implants, have been more efficient to establish picture and printed words selection behaviors - both considered receptive repertoire - than to establish naming pictures and printed words behaviors, which are behaviors associated with expressive reading. In this perspective, it became clear how necessary technological advances in teaching procedures that propose to install and maintain behaviors associated with expressive reading, as effective as teaching procedures that install and maintain behaviors associated with receptive reading. Keywords: stimulus equivalence, cochlear implant, naming.

Achromobacter spp. adaptation in cystic fibrosis infection and candidate biomarkers of antimicrobial resistance

Achromobacter spp. can establish occasional or chronic lung infections in patients with cystic fibrosis (CF). Chronic colonization has been associated with worse prognosis highlighting the need to identify markers of bacterial persistence. To this purpose, we analyzed phenotypic features of 95 Achromobacter spp. isolates from 38 patients presenting chronic or occasional infection. Virulence was tested in Galleria mellonella larvae, cytotoxicity was tested in human bronchial epithelial cells, biofilm production in static conditions was measured by crystal violet staining and susceptibility to selected antibiotics was tested by the disk diffusion method. The presence of genetic loci associated to the analyzed phenotypic features was evaluated by a genome-wide association study. Isolates from occasional infection induced significantly higher mortality of G. mellonella larvae and showed a trend for lower cytotoxicity than chronic infection isolates. No significant difference was observed in biofilm production among the two groups. Additionally, antibiotic susceptibility testing showed that isolates from chronically-infected patients were significantly more resistant to sulfonamides and meropenem than occasional isolates. Candidate genetic biomarkers associated with antibiotic resistance or sensitivity were identified. Achromobacter spp. strains isolated from people with chronic and occasional lung infection exhibit different virulence and antibiotic susceptibility features, which could be linked to persistence in CF lungs. This underlines the possibility of identifying predictive biomarkers of persistence that could be useful for clinical purposes

Everolimus restrains the IL-17A-dependent osteoclast-like transdifferentiation of dendritic cells in multiple myeloma.

Interleukin-17A (IL-17A) promotes the osteoclast (OC)-like differentiation of dendritic cells (DCs) in multiple myeloma (MM), and contributes to the pathogenesis of myeloma bone disease (MBD). In our study, EVR significantly abrogated the in vitro OC-like activity of DCs from 12 MM patients. Exploring the EVR effects, we found that the inhibition of the osteo-erosive activity of OC-DCs was mostly due to the blockade of signals driven by the IL-17A receptor toward CEBPbeta/MAFB axis Therefore, MM patients with MBD would probably benefit from mTOR inhibition

BRAF Mutation Status and Survival after Colorectal Cancer Diagnosis According to Patient and Tumor Characteristics

BRAF mutations in colorectal cancer (CRC) are disproportionately observed in tumors exhibiting microsatellite instability (MSI), and are associated with other prognostic factors. The independent association between BRAF-mutation status and CRC survival, however, remains unclear

Mendelian randomisation implicates hyperlipidaemia as a risk factor for colorectal cancer.

While elevated blood cholesterol has been associated with an increased risk of colorectal cancer (CRC) in observational studies, causality is uncertain. Here we apply a Mendelian randomisation (MR) analysis to examine the potential causal relationship between lipid traits and CRC risk. We used single nucleotide polymorphisms (SNPs) associated with blood levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) as instrumental variables (IV). We calculated MR estimates for each risk factor with CRC using SNP-CRC associations from 9,254 cases and 18,386 controls. Genetically predicted higher TC was associated with an elevated risk of CRC (odds ratios (OR) per unit SD increase = 1.46, 95% confidence interval [CI]: 1.20-1.79, P=1.68x10−4). The pooled ORs for LDL, HDL, and TG were 1.05 (95% CI: 0.92-1.18, P=0.49), 0.94 (95% CI: 0.84-1.05, P= 0.27), and 0.98 (95% CI: 0.85-1.12, P=0.75) respectively. A genetic risk score for 3-hydoxy-3-methylglutaryl-coenzyme A reductase (HMGCR) to mimic the effects of statin therapy was associated with a reduced CRC risk (OR=0.69, 95% CI: 0.49-0.99, P=0.046). This study supports a causal relationship between higher levels of TC with CRC risk, and a further rationale for implementing public health strategies to reduce the prevalence of hyperlipidaemia. This article is protected by copyright. All rights reserved

Calcium signaling and transcription: elongation, DoGs, and eRNAs

The calcium ion (Ca2+) is a key intracellular signaling molecule with far-reaching effects on many cellular processes. One of the most important Ca2+ regulated processes is transcription. A body of literature describes the effect of Ca2+ signaling on transcription initiation as occurring mainly through activation of gene-specific transcription factors by Ca2+-induced signaling cascades. However, the reach of Ca2+ extends far beyond the first step of transcription. In fact, Ca2+ can regulate all phases of transcription, with additional effects on transcription-associated events such as alternative splicing. Importantly, Ca2+ signaling mediates reduced transcription termination in response to certain stress conditions. This reduction allows readthrough transcription, generating a highly inducible and diverse class of downstream of gene containing transcripts (DoGs) that we have recently described