1,794 research outputs found

    Molecular therapies for HCC: Looking outside the box

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    Summary Over the past decade, sorafenib has been the only systemic agent with proven clinical efficacy for patients with unresectable hepatocellular carcinoma (HCC). Recently, lenvatinib was shown to be non-inferior to sorafenib, while regorafenib, cabozantinib, and ramucirumab were shown to be superior to placebo in patients failing sorafenib. In addition, trials of immune checkpoint inhibitors reported encouraging efficacy signals. However, apart from alpha-fetoprotein, which is used to select patients for ramucirumab, no biomarkers are available to identify patients that may respond to a specific treatment. Different synergisms have been postulated based on the potential interplay between antiangiogenic drugs and immunotherapy, with several clinical trials currently testing this hypothesis. Indeed, encouraging preliminary results of phase I studies of bevacizumab plus atezolizumab and lenvatinib plus pembrolizumab have led to the design of ongoing phase III trials, including both antiangiogenics and immune checkpoint inhibitors in the front-line setting. Other important phase II studies have tested molecular therapies directed against different novel targets, such as transforming growth factor-beta, MET (hepatocyte growth factor receptor), and fibroblast growth factor receptor 4. These studies integrated translational research with the aim of better defining the biological tumour profile and identifying tumour and blood biomarkers that select patients who may really benefit from a specific molecular therapy. Importantly, good safety profiles make these drugs suitable for future combinations. In this review, we discuss the most recent data on novel combination strategies and targets, as well as looking ahead to the future role of molecular therapies in the treatment of patients with advanced HCC

    Molecular therapies and precision medicine for hepatocellular carcinoma

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    The global burden of hepatocellular carcinoma (HCC) is increasing and might soon surpass an annual incidence of 1 million cases. Genomic studies have established the landscape of molecular alterations in HCC; however, the most common mutations are not actionable, and only ~25% of tumours harbour potentially targetable drivers. Despite the fact that surveillance programmes lead to early diagnosis in 40–50% of patients, at a point when potentially curative treatments are applicable, almost half of all patients with HCC ultimately receive systemic therapies. Sorafenib was the first systemic therapy approved for patients with advanced-stage HCC, after a landmark study revealed an improvement in median overall survival from 8 to 11 months. New drugs — lenvatinib in the frontline and regorafenib, cabozantinib, and ramucirumab in the second line — have also been demonstrated to improve clinical outcomes, although the median overall survival remains ~1 year; thus, therapeutic breakthroughs are still needed. Immune-checkpoint inhibitors are now being incorporated into the HCC treatment armamentarium and combinations of molecularly targeted therapies with immunotherapies are emerging as tools to boost the immune response. Research on biomarkers of a response or primary resistance to immunotherapies is also advancing. Herein, we summarize the molecular targets and therapies for the management of HCC and discuss the advancements expected in the near future, including biomarker-driven treatments and immunotherapies

    Black Hole Spectroscopy: Testing General Relativity through Gravitational Wave Observations

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    Assuming that general relativity is the correct theory of gravity in the strong field limit, can gravitational wave observations distinguish between black hole and other compact object sources? Alternatively, can gravitational wave observations provide a test of one of the fundamental predictions of general relativity? Here we describe a definitive test of the hypothesis that observations of damped, sinusoidal gravitational waves originated from a black hole or, alternatively, that nature respects the general relativistic no-hair theorem. For astrophysical black holes, which have a negligible charge-to-mass ratio, the black hole quasi-normal mode spectrum is characterized entirely by the black hole mass and angular momentum and is unique to black holes. In a different theory of gravity, or if the observed radiation arises from a different source (e.g., a neutron star, strange matter or boson star), the spectrum will be inconsistent with that predicted for general relativistic black holes. We give a statistical characterization of the consistency between the noisy observation and the theoretical predictions of general relativity, together with a numerical example.Comment: 19 pages, 7 figure

    Optimization of NANOGrav\u27s Time Allocation for Maximum Sensitivity to Single Sources

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    Pulsar timing arrays (PTAs) are a collection of precisely timed millisecond pulsars (MSPs) that can search for gravitational waves (GWs) in the nanohertz frequency range by observing characteristic signatures in the timing residuals. The sensitivity of a PTA depends on the direction of the propagating GW source, the timing accuracy of the pulsars, and the allocation of the available observing time. The goal of this paper is to determine the optimal time allocation strategy among the MSPs in the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) for a single source of GW under a particular set of assumptions. We consider both an isotropic distribution of sources across the sky and a specific source in the Virgo cluster. This work improves on previous efforts by modeling the effect of intrinsic spin noise for each pulsar. We find that, in general, the array is optimized by maximizing time spent on the best-timed pulsars, with sensitivity improvements typically ranging from a factor of 1.5 to 4

    Gene duplications in prokaryotes can be associated with environmental adaptation

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    <p>Abstract</p> <p>Background</p> <p>Gene duplication is a normal evolutionary process. If there is no selective advantage in keeping the duplicated gene, it is usually reduced to a pseudogene and disappears from the genome. However, some paralogs are retained. These gene products are likely to be beneficial to the organism, e.g. in adaptation to new environmental conditions. The aim of our analysis is to investigate the properties of paralog-forming genes in prokaryotes, and to analyse the role of these retained paralogs by relating gene properties to life style of the corresponding prokaryotes.</p> <p>Results</p> <p>Paralogs were identified in a number of prokaryotes, and these paralogs were compared to singletons of persistent orthologs based on functional classification. This showed that the paralogs were associated with for example energy production, cell motility, ion transport, and defence mechanisms. A statistical overrepresentation analysis of gene and protein annotations was based on paralogs of the 200 prokaryotes with the highest fraction of paralog-forming genes. Biclustering of overrepresented gene ontology terms versus species was used to identify clusters of properties associated with clusters of species. The clusters were classified using similarity scores on properties and species to identify interesting clusters, and a subset of clusters were analysed by comparison to literature data. This analysis showed that paralogs often are associated with properties that are important for survival and proliferation of the specific organisms. This includes processes like ion transport, locomotion, chemotaxis and photosynthesis. However, the analysis also showed that the gene ontology terms sometimes were too general, imprecise or even misleading for automatic analysis.</p> <p>Conclusions</p> <p>Properties described by gene ontology terms identified in the overrepresentation analysis are often consistent with individual prokaryote lifestyles and are likely to give a competitive advantage to the organism. Paralogs and singletons dominate different categories of functional classification, where paralogs in particular seem to be associated with processes involving interaction with the environment.</p

    Developing Priorities for the Great Northern Landscape Conservation Cooperative: State Wildlife Action Plans (SWAP) as One Piece of Information

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    Landscape Conservation Cooperatives (LCCs) are public-private partnerships that focus on natural resource challenges which transcend political and jurisdictional boundaries and require a more holistic, collaborative, and adaptive approach to conservation that is firmly grounded in science and strives to ensure the sustainability of land, water, wildlife and cultural resources. The Great Northern LCC, covering Western Montana and parts of several other states and provinces, is nearing completion of a process that synthesizes conservation priorities among the 25 organizations represented on the Steering Committee and their partners. This Strategic Conservation Framework identifies priority species, ecosystems, and ecosystem processes across the landscape represented by the Great Northern LCC based on synthetic summarizations of five state-based Wildlife Action Plans, 40 other regional conservation planning documents, and focused interviews with key personnel across the region. Here we report on the process by which we analyzed data from the State Wildlife Action Plans (SWAPs) of ID, MT, OR, WA, and WY and from Strategic Habitat Conservation as one piece of information for strategic planning. Thirty-five species of greatest conservation need (as defined in the SWAPs) were identified as having commonality across the five states. The ranges of these species were then overlain and a map of areas with the greatest number of species of conservation need can be visualized across the Great Northern LCC
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