A multi-gene signature predicts outcome in patients with pancreatic ductal adenocarcinoma.

© 2014 Haider et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Improved usage of the repertoires of pancreatic ductal adenocarcinoma (PDAC) profiles is crucially needed to guide the development of predictive and prognostic tools that could inform the selection of treatment options

A Genetic Screen for Anchorage-Independent Proliferation in Mammalian Cells Identifies a Membrane-Bound Neuregulin

Anchorage-independent proliferation is a hallmark of oncogenic transformation and is thought to be conducive to proliferation of cancer cells away from their site of origin. We have previously reported that primary Schwann cells expressing the SV40 Large T antigen (LT) are not fully transformed in that they maintain a strict requirement for attachment, requiring a further genetic change, such as oncogenic Ras, to gain anchorage-independence. Using the LT-expressing cells, we performed a genetic screen for anchorage-independent proliferation and identified Sensory and Motor Neuron Derived Factor (SMDF), a transmembrane class III isoform of Neuregulin 1. In contrast to oncogenic Ras, SMDF induced enhanced proliferation in normal primary Schwann cells but did not trigger cellular senescence. In cooperation with LT, SMDF drove anchorage-independent proliferation, loss of contact inhibition and tumourigenicity. This transforming ability was shared with membrane-bound class III but not secreted class I isoforms of Neuregulin, indicating a distinct mechanism of action. Importantly, we show that despite being membrane-bound signalling molecules, class III neuregulins transform via a cell intrinsic mechanism, as a result of constitutive, elevated levels of ErbB signalling at high cell density and in anchorage-free conditions. This novel transforming mechanism may provide new targets for cancer therapy

A case-control study of mastitis: nasal carriage of Staphylococcus aureus

BACKGROUND: Mastitis is a common problem for breastfeeding women. Researchers have called for an investigation into the possible role of maternal nasal carriage of S. aureus in the causation of mastitis in breastfeeding women. METHODS: The aim of the study was to investigate the role of maternal S. aureus nasal carriage in mastitis. Other factors such as infant nasal S. aureus carriage, nipple damage, maternal fatigue and oversupply of milk were also investigated. A case-control design was used. Women with mastitis (cases, n = 100) were recruited from two maternity hospitals in Melbourne, Australia (emergency departments, breastfeeding clinics and postnatal wards). Breastfeeding women without mastitis (controls, n = 99) were recruited from maternal and child health (community) centres and the rooms of a private obstetrician. Women completed a questionnaire and nasal specimens were collected from mother and baby and placed in charcoal transport medium. Women also collected a small sample of milk in a sterile jar. RESULTS: There was no difference between nasal carriage of S. aureus in breastfeeding women with mastitis (42/98, 43%) and control women (45/98, 46%). However, significantly more infants of mothers with mastitis were nasal carriers of S. aureus (72/88, 82%) than controls (52/93, 56%). The association was strong (adjusted OR 3.23, 95%CI 1.30, 8.27) after adjustment for the following confounding factors: income, private health insurance, difficulty with breastfeeding, nipple damage and tight bra. There was also a strong association between nipple damage and mastitis (adjusted OR 9.34, 95%CI 2.99, 29.20). CONCLUSION: We found no association between maternal nasal carriage of S. aureus and mastitis, but nasal carriage in the infant was associated with breast infections. As in other studies of mastitis, we found a strong association between nipple damage and mastitis. Prevention of nipple damage is likely to reduce the incidence of infectious mastitis. Mothers need good advice about optimal attachment of the baby to the breast and access to skilled help in the early postpartum days and weeks

HSPVdb—the Human Short Peptide Variation Database for improved mass spectrometry-based detection of polymorphic HLA-ligands

T cell epitopes derived from polymorphic proteins or from proteins encoded by alternative reading frames (ARFs) play an important role in (tumor) immunology. Identification of these peptides is successfully performed with mass spectrometry. In a mass spectrometry-based approach, the recorded tandem mass spectra are matched against hypothetical spectra generated from known protein sequence databases. Commonly used protein databases contain a minimal level of redundancy, and thus, are not suitable data sources for searching polymorphic T cell epitopes, either in normal or ARFs. At the same time, however, these databases contain much non-polymorphic sequence information, thereby complicating the matching of recorded and theoretical spectra, and increasing the potential for finding false positives. Therefore, we created a database with peptides from ARFs and peptide variation arising from single nucleotide polymorphisms (SNPs). It is based on the human mRNA sequences from the well-annotated reference sequence (RefSeq) database and associated variation information derived from the Single Nucleotide Polymorphism Database (dbSNP). In this process, we removed all non-polymorphic information. Investigation of the frequency of SNPs in the dbSNP revealed that many SNPs are non-polymorphic “SNPs”. Therefore, we removed those from our dedicated database, and this resulted in a comprehensive high quality database, which we coined the Human Short Peptide Variation Database (HSPVdb). The value of our HSPVdb is shown by identification of the majority of published polymorphic SNP- and/or ARF-derived epitopes from a mass spectrometry-based proteomics workflow, and by a large variety of polymorphic peptides identified as potential T cell epitopes in the HLA-ligandome presented by the Epstein–Barr virus cells

Fucans, but Not Fucomannoglucuronans, Determine the Biological Activities of Sulfated Polysaccharides from Laminaria saccharina Brown Seaweed

Sulfated polysaccharides from Laminaria saccharina (new name: Saccharina latissima) brown seaweed show promising activity for the treatment of inflammation, thrombosis, and cancer; yet the molecular mechanisms underlying these properties remain poorly understood. The aim of this work was to characterize, using in vitro and in vivo strategies, the anti-inflammatory, anti-coagulant, anti-angiogenic, and anti-tumor activities of two main sulfated polysaccharide fractions obtained from L. saccharina: a) L.s.-1.0 fraction mainly consisting of O-sulfated mannoglucuronofucans and b) L.s.-1.25 fraction mainly composed of sulfated fucans. Both fractions inhibited leukocyte recruitment in a model of inflammation in rats, although L.s.-1.25 appeared to be more active than L.s.-1.0. Also, these fractions inhibited neutrophil adhesion to platelets under flow. Only fraction L.s.-1.25, but not L.s.-1.0, displayed anticoagulant activity as measured by the activated partial thromboplastin time. Investigation of these fractions in angiogenesis settings revealed that only L.s.-1.25 strongly inhibited fetal bovine serum (FBS) induced in vitro tubulogenesis. This effect correlated with a reduction in plasminogen activator inhibitor-1 (PAI-1) levels in L.s.-1.25-treated endothelial cells. Furthermore, only parent sulfated polysaccharides from L. saccharina (L.s.-P) and its fraction L.s.-1.25 were powerful inhibitors of basic fibroblast growth factor (bFGF) induced pathways. Consistently, the L.s.-1.25 fraction as well as L.s.-P successfully interfered with fibroblast binding to human bFGF. The incorporation of L.s.-P or L.s.-1.25, but not L.s.-1.0 into Matrigel plugs containing melanoma cells induced a significant reduction in hemoglobin content as well in the frequency of tumor-associated blood vessels. Moreover, i.p. administrations of L.s.-1.25, as well as L.s.-P, but not L.s.-1.0, resulted in a significant reduction of tumor growth when inoculated into syngeneic mice. Finally, L.s.-1.25 markedly inhibited breast cancer cell adhesion to human platelet-coated surfaces. Thus, sulfated fucans are mainly responsible for the anti-inflammatory, anticoagulant, antiangiogenic, and antitumor activities of sulfated polysaccharides from L. saccharina brown seaweed

Mechanisms Underlying Interferon-γ-Induced Priming of Microglial Reactive Oxygen Species Production.

Microglial priming and enhanced reactivity to secondary insults cause substantial neuronal damage and are hallmarks of brain aging, traumatic brain injury and neurodegenerative diseases. It is, thus, of particular interest to identify mechanisms involved in microglial priming. Here, we demonstrate that priming of microglia with interferon-γ (IFN γ) substantially enhanced production of reactive oxygen species (ROS) following stimulation of microglia with ATP. Priming of microglial ROS production was substantially reduced by inhibition of p38 MAPK activity with SB203580, by increases in intracellular glutathione levels with N-Acetyl-L-cysteine, by blockade of NADPH oxidase subunit NOX2 activity with gp91ds-tat or by inhibition of nitric oxide production with L-NAME. Together, our data indicate that priming of microglial ROS production involves reduction of intracellular glutathione levels, upregulation of NADPH oxidase subunit NOX2 and increases in nitric oxide production, and suggest that these simultaneously occurring processes result in enhanced production of neurotoxic peroxynitrite. Furthermore, IFNγ-induced priming of microglial ROS production was reduced upon blockade of Kir2.1 inward rectifier K+ channels with ML133. Inhibitory effects of ML133 on microglial priming were mediated via regulation of intracellular glutathione levels and nitric oxide production. These data suggest that microglial Kir2.1 channels may represent novel therapeutic targets to inhibit excessive ROS production by primed microglia in brain pathology

Comparative evaluation of methods for estimating retinal ganglion cell loss in retinal sections and wholemounts

To investigate the reliability of different methods of quantifying retinal ganglion cells (RGCs) in rat retinal sections and wholemounts from eyes with either intact optic nerves or those axotomised after optic nerve crush (ONC). Adult rats received a unilateral ONC and after 21 days the numbers of Brn3a+ , bIII-tubulin+ and Islet-1+ RGCs were quantified in either retinal radial sections or wholemounts in which FluoroGold (FG) was injected 48 h before harvesting. Phenotypic antibody markers were used to distinguish RGCs from astrocytes, macrophages/microglia and amacrine cells. In wholemounted retinae, counts of FG+ and Brn3a+ RGCs were of similar magnitude in eyes with intact optic nerves and were similarly reduced after ONC. Larger differences in RGC number were detected between intact and ONC groups when images were taken closer to the optic nerve head. In radial sections, Brn3a did not stain astrocytes, macrophages/microglia or amacrine cells, whereas βIII-tubulin and Islet-1 did localize to amacrine cells as well as RGCs. The numbers of βIII-tubulin+ RGCs was greater than Brn3a+ RGCs, both in retinae from eyes with intact optic nerves and eyes 21 days after ONC. Islet-1 staining also overestimated the number of RGCs compared to Brn3a, but only after ONC. Estimates of RGC loss were similar in Brn3astained radial retinal sections compared to both Brn3a-stained wholemounts and retinal wholemounts in which RGCs were backfilled with FG, with sections having the added advantage of reducing experimental animal usage

Atrophy in the parahippocampal gyrus as an early biomarker of Alzheimer’s disease

The main aim of the present study was to compare volume differences in the hippocampus and parahippocampal gyrus as biomarkers of Alzheimer’s disease (AD). Based on the previous findings, we hypothesized that there would be significant volume differences between cases of healthy aging, amnestic mild cognitive impairment (aMCI), and mild AD. Furthermore, we hypothesized that there would be larger volume differences in the parahippocampal gyrus than in the hippocampus. In addition, we investigated differences between the anterior, middle, and posterior parts of both structures. We studied three groups of participants: 18 healthy participants without memory decline, 18 patients with aMCI, and 18 patients with mild AD. 3 T T1-weighted MRI scans were acquired and gray matter volumes of the anterior, middle, and posterior parts of both the hippocampus and parahippocampal gyrus were measured using a manual tracing approach. Volumes of both the hippocampus and parahippocampal gyrus were significantly different between the groups in the following order: healthy > aMCI > AD. Volume differences between the groups were relatively larger in the parahippocampal gyrus than in the hippocampus, in particular, when we compared healthy with aMCI. No substantial differences were found between the anterior, middle, and posterior parts of both structures. Our results suggest that parahippocampal volume discriminates better than hippocampal volume between cases of healthy aging, aMCI, and mild AD, in particular, in the early phase of the disease. The present results stress the importance of parahippocampal atrophy as an early biomarker of AD

Infection and Transmission of Rift Valley Fever Viruses Lacking the NSs and/or NSm Genes in Mosquitoes: Potential Role for NSm in Mosquito Infection

Rift Valley fever virus is transmitted mainly by mosquitoes and causes disease in humans and animals throughout Africa and the Arabian Peninsula. The impact of disease is large in terms of human illness and mortality, and economic impact on the livestock industry. For these reasons, and because there is a risk of this virus spreading to Europe and North America, it is important to develop a vaccine that is stable, safe and effective in preventing infection. Potential vaccine viruses have been developed through deletion of two genes (NSs and NSm) affecting virus virulence. Because this virus is normally transmitted by mosquitoes we must determine the effects of the deletions in these vaccine viruses on their ability to infect and be transmitted by mosquitoes. An optimal vaccine virus would not infect or be transmitted. The viruses were tested in two mosquito species: Aedes aegypti and Culex quinquefasciatus. Deletion of the NSm gene reduced infection of Ae. aegypti mosquitoes indicating a role for the NSm protein in mosquito infection. The virus with deletion of both NSs and NSm genes was the best vaccine candidate since it did not infect Ae. aegypti and showed reduced infection and transmission rates in Cx. quinquefasciatus