112 research outputs found

    The Waters of The Third Pole: Sources of Threat, Sources of Survival

    Get PDF
    The purpose of this report is to open up a dialogue on an issue that could put the lives and livelihoods of millions of people at risk in the foreseeable future. This issue is water – water as a vital resource and as a potential crisis driver in the Hindu-Kush Himalaya (HKH) region. In seeking to foster that dialogue, the report has three specific objectives: [i] to survey various types of potential water-related hazards and crisis drivers that could affect the region; [ii] to foster new types of alliances – including greater attention to what will be called humanitarian policy-maker/ science dialogues – for addressing the threats that the region may face; and [iii] to propose first steps that must be taken now to lead to prevention and preparedness measures commensurate with the nature and scale of threats facing the region

    Scoping potential routes to UK civil unrest via the food system: results of a structured expert elicitation

    Get PDF
    We report the results of a structured expert elicitation to identify the most likely types of potential food system disruption scenarios for the UK, focusing on routes to civil unrest. We take a backcasting approach by defining as an end-point a Societal Event in which 1 in 2,000 people have been injured in the UK, which 40% of experts rated as “Possible (20–50%)” or “More likely than not (50–80%)” or “Very likely (>80%)” over the coming decade. Over a longer timeframe of 50 years, nearly 80% of experts rated such an event as “Possible (20–50%)” or “More likely than not (50–80%)” or “Very likely (>80%)”. The experts considered two food system scenarios and ranked their plausibility of contributing to the given societal scenario. For a timescale of 10 years the majority identified a food distribution problem as the most likely. Over a timescale of 50 years the experts were more evenly split between the two scenarios, but over half thought the most likely route to civil unrest would be a lack of total food in the UK. Overall, in the next 50 years, 45% of participants said there is a greater than 20% chance of civil unrest due to insufficient food in the UK due to extreme weather or ecological collapse. However, the experts stressed that the various causes are interconnected, can create cascading risks and highlighted the importance of a systems approach. We encourage food system stakeholders to use these results in their risk planning, and recommend future work to support prevention, preparedness, response and recovery planning

    Prioritizing genes associated with prostate cancer development

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The genetic control of prostate cancer development is poorly understood. Large numbers of gene-expression datasets on different aspects of prostate tumorigenesis are available. We used these data to identify and prioritize candidate genes associated with the development of prostate cancer and bone metastases. Our working hypothesis was that combining meta-analyses on different but overlapping steps of prostate tumorigenesis will improve identification of genes associated with prostate cancer development.</p> <p>Methods</p> <p>A <it>Z </it>score-based meta-analysis of gene-expression data was used to identify candidate genes associated with prostate cancer development. To put together different datasets, we conducted a meta-analysis on 3 levels that follow the natural history of prostate cancer development. For experimental verification of candidates, we used in silico validation as well as in-house gene-expression data.</p> <p>Results</p> <p>Genes with experimental evidence of an association with prostate cancer development were overrepresented among our top candidates. The meta-analysis also identified a considerable number of novel candidate genes with no published evidence of a role in prostate cancer development. Functional annotation identified cytoskeleton, cell adhesion, extracellular matrix, and cell motility as the top functions associated with prostate cancer development. We identified 10 genes--<it>CDC2, CCNA2, IGF1, EGR1, SRF, CTGF, CCL2, CAV1, SMAD4</it>, and <it>AURKA</it>--that form hubs of the interaction network and therefore are likely to be primary drivers of prostate cancer development.</p> <p>Conclusions</p> <p>By using this large 3-level meta-analysis of the gene-expression data to identify candidate genes associated with prostate cancer development, we have generated a list of candidate genes that may be a useful resource for researchers studying the molecular mechanisms underlying prostate cancer development.</p

    Gene Expression Profiling Reveals New Aspects of PIK3CA Mutation in ERalpha-Positive Breast Cancer: Major Implication of the Wnt Signaling Pathway

    Get PDF
    BACKGROUND: The PI3K/AKT pathway plays a pivotal role in breast cancer development and maintenance. PIK3CA, encoding the PI3K catalytic subunit, is the oncogene exhibiting a high frequency of gain-of-function mutations leading to PI3K/AKT pathway activation in breast cancer. PIK3CA mutations have been observed in 30% to 40% of ERα-positive breast tumors. However the physiopathological role of PIK3CA mutations in breast tumorigenesis remains largely unclear. METHODOLOGY/PRINCIPAL FINDINGS: To identify relevant downstream target genes and signaling activated by aberrant PI3K/AKT pathway in breast tumors, we first analyzed gene expression with a pangenomic oligonucleotide microarray in a series of 43 ERα-positive tumors with and without PIK3CA mutations. Genes of interest were then investigated in 249 ERα-positive breast tumors by real-time quantitative RT-PCR. A robust collection of 19 genes was found to be differently expressed in PIK3CA-mutated tumors. PIK3CA mutations were associated with over-expression of several genes involved in the Wnt signaling pathway (WNT5A, TCF7L2, MSX2, TNFRSF11B), regulation of gene transcription (SEC14L2, MSX2, TFAP2B, NRIP3) and metal ion binding (CYP4Z1, CYP4Z2P, SLC40A1, LTF, LIMCH1). CONCLUSION/SIGNIFICANCE: This new gene set should help to understand the behavior of PIK3CA-mutated cancers and detailed knowledge of Wnt signaling activation could lead to novel therapeutic strategies

    Androgen receptor footprint on the way to prostate cancer progression

    Get PDF
    The prostate gland is exquisitely sensitive to androgen receptor (AR) signaling. AR signaling is obligatory for prostate development and changes in AR levels, its ligands or shifts in AR mode of action are reflected in the physiology of the prostate. The AR is intimately linked to prostate cancer biology through the regulation of epithelial proliferation, suppression of apoptosis and the development of castration-resistant disease. Thus, AR is the primary therapeutic target in various prostate diseases such as BPH and cancer. Although some tumors lose AR expression, most retain the AR and have elevated levels and/or shifts in activity that are required for tumor progression and metastasis. New AR inhibitors currently in clinical trials with higher receptor affinity and specificity may improve prostate cancer patient outcome. Several events play an important role in initiation, primary tumor development and metastatic spread. Androgen receptor activity and promoter specificity change due to altered coregulator expression. Changes in epigenetic surveillance alter the AR cistrome. Both systemic and local inflammation increases with PCa progression affecting AR levels, activity, and requirement for ligand. Our current understanding of AR biology suggest that global androgen suppression may drive the development of castration-resistant disease and therefore the question remains: Does effective inhibition of AR activity mark the end of the road for PCa or only a sharp turn toward a different type of malignancy

    Dunning rat prostate adenocarcinomas and alternative splicing reporters: powerful tools to study epithelial plasticity in prostate tumors in vivo

    Get PDF
    Using alternative splicing reporters we have previously observed mesenchymal epithelial transitions in Dunning AT3 rat prostate tumors. We demonstrate here that the Dunning DT and AT3 cells, which express epithelial and mesenchymal markers, respectively, represent an excellent model to study epithelial transitions since these cells recapitulate gene expression profiles observed during human prostate cancer progression. In this manuscript we also present the development of two new tools to study the epithelial transitions by imaging alternative splicing decisions: a bichromatic fluorescence reporter to evaluate epithelial transitions in culture and in vivo, and a luciferase reporter to visualize the distribution of mesenchymal epithelial transitions in vivo

    Gene expression profiles of prostate cancer reveal involvement of multiple molecular pathways in the metastatic process

    Get PDF
    BACKGROUND: Prostate cancer is characterized by heterogeneity in the clinical course that often does not correlate with morphologic features of the tumor. Metastasis reflects the most adverse outcome of prostate cancer, and to date there are no reliable morphologic features or serum biomarkers that can reliably predict which patients are at higher risk of developing metastatic disease. Understanding the differences in the biology of metastatic and organ confined primary tumors is essential for developing new prognostic markers and therapeutic targets. METHODS: Using Affymetrix oligonucleotide arrays, we analyzed gene expression profiles of 24 androgen-ablation resistant metastatic samples obtained from 4 patients and a previously published dataset of 64 primary prostate tumor samples. Differential gene expression was analyzed after removing potentially uninformative stromal genes, addressing the differences in cellular content between primary and metastatic tumors. RESULTS: The metastatic samples are highly heterogenous in expression; however, differential expression analysis shows that 415 genes are upregulated and 364 genes are downregulated at least 2 fold in every patient with metastasis. The expression profile of metastatic samples reveals changes in expression of a unique set of genes representing both the androgen ablation related pathways and other metastasis related gene networks such as cell adhesion, bone remodelling and cell cycle. The differentially expressed genes include metabolic enzymes, transcription factors such as Forkhead Box M1 (FoxM1) and cell adhesion molecules such as Osteopontin (SPP1). CONCLUSION: We hypothesize that these genes have a role in the biology of metastatic disease and that they represent potential therapeutic targets for prostate cancer

    Characterization of an Nmr Homolog That Modulates GATA Factor-Mediated Nitrogen Metabolite Repression in Cryptococcus neoformans

    Get PDF
    Nitrogen source utilization plays a critical role in fungal development, secondary metabolite production and pathogenesis. In both the Ascomycota and Basidiomycota, GATA transcription factors globally activate the expression of catabolic enzyme-encoding genes required to degrade complex nitrogenous compounds. However, in the presence of preferred nitrogen sources such as ammonium, GATA factor activity is inhibited in some species through interaction with co-repressor Nmr proteins. This regulatory phenomenon, nitrogen metabolite repression, enables preferential utilization of readily assimilated nitrogen sources. In the basidiomycete pathogen Cryptococcus neoformans, the GATA factor Gat1/Are1 has been co-opted into regulating multiple key virulence traits in addition to nitrogen catabolism. Here, we further characterize Gat1/Are1 function and investigate the regulatory role of the predicted Nmr homolog Tar1. While GAT1/ARE1 expression is induced during nitrogen limitation, TAR1 transcription is unaffected by nitrogen availability. Deletion of TAR1 leads to inappropriate derepression of non-preferred nitrogen catabolic pathways in the simultaneous presence of favoured sources. In addition to exhibiting its evolutionary conserved role of inhibiting GATA factor activity under repressing conditions, Tar1 also positively regulates GAT1/ARE1 transcription under non-repressing conditions. The molecular mechanism by which Tar1 modulates nitrogen metabolite repression, however, remains open to speculation. Interaction between Tar1 and Gat1/Are1 was undetectable in a yeast two-hybrid assay, consistent with Tar1 and Gat1/Are1 each lacking the conserved C-terminus regions present in ascomycete Nmr proteins and GATA factors that are known to interact with each other. Importantly, both Tar1 and Gat1/Are1 are suppressors of C. neoformans virulence, reiterating and highlighting the paradigm of nitrogen regulation of pathogenesis
    corecore