Constitutive nuclear factor kB (NF-kB) activation is a hallmark of colon tumor growth. Cyclin-dependent kinases (CDKs) are critical cell-cycle regulators, and inhibition of CDK activity has been used successfully as anticancer therapy. Here, we show that the NFE2L3 transcription factor functions as a key regulator in a pathway that links NF-kB signaling to the control of CDK1 activity, thereby driving colon cancer cell proliferation. We found that NFE2L3 expression is regulated by the RELA subunit of NF-kB and that NFE2L3 levels are elevated in patients with colon adenocarcinoma when compared with normal adjacent tissue. Silencing of NFE2L3 significantly decreases colon cancer cell proliferation in vitro and tumor growth in vivo. NFE2L3 knockdown results in increased levels of double homeobox factor 4 (DUX4), which functions as a direct inhibitor of CDK1. The discovered oncogenic pathway governing cell-cycle progression may open up unique avenues for precision cancer therapy.

Cytokines play key roles in a variety of reproductive processes including normal parturition as well as preterm birth. Our previous data have shown that MAFF , a member of the MAF family of bZIP transcription factors, is rapidly induced by pro‐inflammatory cytokines in PHM 1‐31 myometrial cells. We performed loss‐of‐function studies in PHM 1‐31 cells to identify MAFF dependent genes. We showed that knockdown of MAFF significantly decreased CXCL 1 chemokine and CSF 3 cytokine transcript and protein levels. Using chromatin immunoprecipitation analyzes, we confirmed CXCL 1 and CSF 3 genes as direct MAFF targets. We also demonstrated that MAFF function in PHM 1‐31 myometrial cells is able to control cytokine and matrix metalloproteinase gene expression in THP ‐1 monocytic cells in a paracrine fashion. Our studies provide valuable insights into the MAFF dependent transcriptional network governing myometrial cell function. The data suggest a role of MAFF in parturition and/or infection‐induced preterm labour through modulation of inflammatory processes in the microenvironment.

BackgroundMyogenesis is initiated by myoblast differentiation and fusion to form myotubes and muscle fibres. A population of myoblasts, known as satellite cells, is responsible for post-natal growth of muscle and for its regeneration. This differentiation requires many changes in cell behaviour and its surrounding environment. These modifications are tightly regulated over time and can be characterized through the study of changes in gene expression associated with this process. During the initial myogenesis steps, using the myoblast cell line C2C12 as a model, Janot et al. (2009) showed significant variations in expression for genes involved in pathways of glycolipid synthesis. In this study we used murine satellite cells (MSC) and their ability to differentiate into myotubes or early fat storage cells to select glycosylation related genes whose variation of expression is myogenesis specific.ResultsThe comparison of variant genes in both MSC differentiation pathways identified 67 genes associated with myogenesis. Comparison with data obtained for C2C12 revealed that only 14 genes had similar expression profiles in both cell types and that 17 genes were specifically regulated in MSC. Results were validated statistically by without a priori clustering. Classification according to protein function encoded by these 31 genes showed that the main regulated cellular processes during this differentiation were (i) remodeling of the extracellular matrix, particularly, sulfated structures, (ii) down-regulation of O-mannosyl glycan biosynthesis, and (iii) an increase in adhesion protein expression. A functional study was performed on Itga11 and Chst5 encoding two highly up-regulated proteins. The inactivation of Chst5 by specific shRNA delayed the fusion of MSC. By contrast, the inactivation of Itga11 by specific shRNA dramatically decreased the fusion ability of MSC. This result was confirmed by neutralization of Itga11 product by specific antibodies.ConclusionsOur screening method detected 31 genes specific for myogenic differentiation out of the 383 genes studied. According to their function, interaction networks of the products of these selected genes converged to cell fusion. Functional studies on Itga11 and Chst5 demonstrated the robustness of this screening.

We investigated the role of the NFE2L3 transcription factor in inflammation-induced colorectal cancer. Our studies revealed that Nfe2l3−/− mice exhibit significantly less inflammation in the colon, reduced tumor size and numbers, and skewed localization of tumors with a more pronounced decrease of tumors in the distal colon. CIBERSORT analysis of RNA-seq data from normal and tumor tissue predicted a reduction in mast cells in Nfe2l3−/− animals, which was confirmed by toluidine blue staining. Concomitantly, the transcript levels of Il33 and Rab27a, both important regulators of mast cells, were reduced and increased, respectively, in the colorectal tumors of Nfe2l3−/− mice. Furthermore, we validated NFE2L3 binding to the regulatory sequences of the IL33 and RAB27A loci in human colorectal carcinoma cells. Using digital spatial profiling, we found that Nfe2l3−/− mice presented elevated FOXP3 and immune checkpoint markers CTLA4, TIM3, and LAG3, suggesting an increase in Treg counts. Staining for CD3 and FOXP3 confirmed a significant increase in immunosuppressive Tregs in the colon of Nfe2l3−/− animals. Also, Human Microbiome Project (HMP2) data showed that NFE2L3 transcript levels are higher in the rectum of ulcerative colitis patients. The observed changes in the tumor microenvironment provide new insights into the molecular differences regarding colon cancer sidedness. This may be exploited for the treatment of early-onset colorectal cancer as this emerging subtype primarily displays distal/left-sided tumors.

Zika virus (ZIKV) infection of neurons leads to neurological complications and congenital malformations of the brain of neonates. To date, ZIKV mechanism of infection and pathogenesis is not entirely understood and different studies on gene regulation of ZIKV-infected cells have identified a dysregulation of inflammatory and stem cell maintenance pathways. MicroRNAs (miRNAs) are post-transcriptional regulators of cellular genes and they contribute to cell development in normal function and disease. Previous reports with integrative analyses of messenger RNAs (mRNAs) and miRNAs during ZIKV infection have not identified neurological pathway defects. We hypothesized that dysregulation of pathways involved in neurological functions will be identified by RNA profiling of ZIKV-infected fetal neurons. We therefore used microarrays to analyze gene expression levels following ZIKV infection of fetal murine neurons. We observed that the expression levels of transcription factors such as neural PAS domain protein 4 (Npas4) and of three members of the orphan nuclear receptor 4 (Nr4a) were severely decreased after viral infection. We confirmed that their downregulation was at both the mRNA level and at the protein level. The dysregulation of these transcription factors has been previously linked to aberrant neural functions and development. We next examined the miRNA expression profile in infected primary murine neurons by microarray and found that various miRNAs were dysregulated upon ZIKV infection. An integrative analysis of the differentially expressed miRNAs and mRNAs indicated that miR-7013-5p targets Nr4a3 gene. Using miRmimics, we corroborated that miR-7013-5p downregulates Nr4a3 mRNA and protein levels. Our data identify a profound dysregulation of neural transcription factors with an overexpression of miR-7013-5p that results in decreased Nr4a3 expression, likely a main contributor to ZIKV-induced neuronal dysfunction.

IntroductionDysfunctional transcriptional and signalling networks play a fundamental role in colorectal cancer (CRC), one of the most common and fatal malignancies worldwide. Different molecular CRC subtypes have been identified, and understanding of the underlying pathogenesis of CRC formation is crucial for predicting prognosis and treatment response. Constitutive NF-κB activation is a hallmark of colon tumour development. In this study, we aimed to unravel the cellular network governing NFE2L3 regulation and function. We report that NFE2L3 acts as a central player in a newly identified NF-kB signalling pathway that controls colon cancer cell growth.Material and methodsWe analysed the level of NFE2L3 in colon cancer samples extracted from patients. We compared by qPCR and immunohistochemistry the level NFE2L3 expression in normal and tumour tissues. We performed a knockdown of NFE2L3 in different colon cancer cell lines. We characterised the phenotype associated to its depletion in vitro and in vivo. Then, we used a CHIP sequencing analysis to identify the targets of NFE2L3 in our models and we validated by qPCR the direct link between NFE2L3 expression and targets discovered. Finally, by using a strategy of immunoprecipitation associated to mass spectrometry analysis, we identified potential proteins implicated in the pathway of NFE2L3 in colon cancer.Results and discussionsFirstly, we observed that the expression of NFE2L3 in colon cancer samples is significantly higher compared to in normal colon tissues. Moreover, the expression of this protein directly correlated to the survival of patients and could be used as a prognostic marker in colon adenocarcinoma. After that, we depleted the expression of NFE2L3 and we observed that the proliferation of colon cancer cells was slow down. Then, we identified NF-kB pathway as a key regulator of NFE2L3 expression by regulating promoter region. Finally, we demonstrated that NFE2L3 controls the cell cycle in cancer cells by modulating the expression of negative regulators of proliferation.ConclusionTaken together, based on our observations, we propose the existence of a novel oncogenic pathway, comprising the NF–kB, NFE2L3 and cell cycle regulators, that controls cancer cell growth. Our study establishes a key role for the NFE2L3 transcription factor that regulates cell cycle progression in colon cancer cells.

A polychrome and gilded wooden artifact was found, in a heavily deteriorated state, in the stores of the Mdina Cathedral Museum, Malta. The object represents two zoomorphic angels holding a coat of arms. Stylistically, the artifact matches with parts of a late 16th century Organ balcony, currently exhibited at the same Museum. The present study aims to establish whether or not the newly recovered artifact might have formed part of the balcony ensemble by means of material identification techniques. The combined use of XRF, FT-IR and FT-Raman spectroscopy ensure a detailed characterization of the material used. In the case of pigments, for both artifacts the blue pigment was smalt, while cinnabar was used for red and flesh tones. The metallic decorative parts of the panels are gilded, confirmed by the presence of Au peaks in the X-ray spectra. The supporting structure of both artifacts was manufactured from poplar wood.