Zinc transporter HKE4 as a new target in antihormone resistance of breast cancer

Background Oestrogen receptor-positive breast cancers develop resistance to anti-oestrogens by utilising alternative growth factor pathways as observed in our tamoxifen-resistant cell line (TAMR). These include EGFR, IGF1-R and Src signalling as well as increased growth and invasion. Zinc is elevated in breast cancer tissue and has been demonstrated to activate certain growth factor signalling pathways. We have tested the expression level of members of the LIV-1 family of zinc influx transporters and discovered that HKE4 (SLC39A7, ZIP7), previously shown by us capable of increasing the intracellular zinc levels, has increased expression in TAMR. We have therefore investigated whether the development of the more aggressive phenotype observed in our TAMR cells, including activation of these signalling pathways as well as increased growth and invasion, is due to an increase of intracellular zinc and as a direct result of increased expression of HKE4. Methods All nine members of the LIV-1 subfamily of ZIP transporters were measured in our model of tamoxifen-resistant breast cancer using Affymetrix arrays. Zinc-induced activation of growth factor signalling pathway components was investigated by western blot and/or fluorescent microscopy. Short-term (15-min) treatments with 20 μM zinc included ionophore, whereas long-term (hours/days) did not. Recombinant LIV-1 family members with a V5 tag were expressed using pcDNA3.1/V5-His-TOPO vector, and siRNA (Dharmacon smartpools with relevant controls) was used to reduce endogenous expression. Results HKE4 (SLC39A7), a ZIP transporter from the LIV-1 subfamily, was discovered to be elevated in TAMR cells by Affymetrix analysis and confirmed by PCR and western blot. We have observed that our TAMR cells have a twofold increase in intracellular zinc compared with wild-type cells, using the zinc-specific fluorescent dye Newport Green. Short-term zinc treatment of TAMR cells activates the signalling pathways implicated in antihormone-resistant proliferation and is reduced by both the zinc chelator TPEN and the Src kinase inhibitor SU6556. The same effects are observed after longer term (6 days) zinc treatment with additional increases in cell growth and invasion through Matrigel. Since we have previously demonstrated that HKE4 is capable of increasing intracellular zinc in cells and, more recently, that these TAMR have elevated intracellular zinc levels, we have tested the hypothesis that elevated HKE4 expression is directly responsible for the aggressive phenotype observed in our TAMR cells. Reducing HKE4 levels by siRNA demonstrated a role for this molecule in driving the zinc-induced activation of multiple signalling pathways. In the presence of siRNA for HKE4, the previously observed zinc-induced activation of EGFR, Src, and IGF1-R was eradicated and the EGF-stimulated activation was also decreased. Additionally, we have demonstrated the converse by transfecting recombinant HKE4 into wild-type cells and/or treating them with zinc to observe the activation of these signalling pathways and increases in invasive capability. Interestingly, we have observed a similar role of HKE4 in our model of faslodex-resistant breast cancer. Conclusion The presented results propose that HKE4, a member of the LIV-1 subfamily of ZIP transporters, is directly involved in the activation of the aggressive phenotype observed with the development of antihormone resistance, and as such is a potential new target for the prevention of resistance to antihormones in breast cancer progression

Diversity of Reactive Astrogliosis in CNS Pathology: Heterogeneity or Plasticity?

Astrocytes are essential for the development and homeostatic maintenance of the central nervous system (CNS). They are also critical players in the CNS injury response during which they undergo a process referred to as "reactive astrogliosis." Diversity in astrocyte morphology and gene expression, as revealed by transcriptional analysis, is well-recognized and has been reported in several CNS pathologies, including ischemic stroke, CNS demyelination, and traumatic injury. This diversity appears unique to the specific pathology, with significant variance across temporal, topographical, age, and sex-specific variables. Despite this, there is limited functional data corroborating this diversity. Furthermore, as reactive astrocytes display significant environmental-dependent plasticity and fate-mapping data on astrocyte subsets in the adult CNS is limited, it remains unclear whether this diversity represents heterogeneity or plasticity. As astrocytes are important for neuronal survival and CNS function post-injury, establishing to what extent this diversity reflects distinct established heterogeneous astrocyte subpopulations vs. environmentally dependent plasticity within established astrocyte subsets will be critical for guiding therapeutic development. To that end, we review the current state of knowledge on astrocyte diversity in the context of three representative CNS pathologies: ischemic stroke, demyelination, and traumatic injury, with the goal of identifying key limitations in our current knowledge and suggesting future areas of research needed to address them. We suggest that the majority of identified astrocyte diversity in CNS pathologies to date represents plasticity in response to dynamically changing post-injury environments as opposed to heterogeneity, an important consideration for the understanding of disease pathogenesis and the development of therapeutic interventions

Case report: a diagnostically challenging conjunctival mass caused by the Epstein-Barr virus.

We present a paediatric case of infectious mononucleosis in a 13-year old, manifesting with follicular conjunctivitis and a conjunctival mass in one eye with no evidence of leucocytosis on the blood count. The diagnosis was confirmed following surgical excision and biopsy. The case represented a diagnostic challenge due to its atypism and given the steady increase in the prevalence of EBV-related ocular diseases in the last years, this report can serve as an example to prompt earlier serological tests to identify the aetiology in similar cases. This is important because EBV can be treated with acyclovir early in the active viral phase

A new diagrammatic representation for correlation functions in the in-in formalism

In this paper we provide an alternative method to compute correlation functions in the in-in formalism, with a modified set of Feynman rules to compute loop corrections. The diagrammatic expansion is based on an iterative solution of the equation of motion for the quantum operators with only retarded propagators, which makes each diagram intrinsically local (whereas in the standard case locality is the result of several cancellations) and endowed with a straightforward physical interpretation. While the final result is strictly equivalent, as a bonus the formulation presented here also contains less graphs than other diagrammatic approaches to in-in correlation functions. Our method is particularly suitable for applications to cosmology.Comment: 14 pages, matches the published version. includes a modified version of axodraw.sty that works with the Revtex4 clas

Short-term efficacy of physical interventions in osteoarthritic knee pain. A systematic review and meta-analysis of randomised placebo-controlled trials.

BACKGROUND: Treatment efficacy of physical agents in osteoarthritis of the knee (OAK) pain has been largely unknown, and this systematic review was aimed at assessing their short-term efficacies for pain relief. METHODS: Systematic review with meta-analysis of efficacy within 1-4 weeks and at follow up at 1-12 weeks after the end of treatment. RESULTS: 36 randomised placebo-controlled trials (RCTs) were identified with 2434 patients where 1391 patients received active treatment. 33 trials satisfied three or more out of five methodological criteria (Jadad scale). The patient sample had a mean age of 65.1 years and mean baseline pain of 62.9 mm on a 100 mm visual analogue scale (VAS). Within 4 weeks of the commencement of treatment manual acupuncture, static magnets and ultrasound therapies did not offer statistically significant short-term pain relief over placebo. Pulsed electromagnetic fields offered a small reduction in pain of 6.9 mm [95% CI: 2.2 to 11.6] (n = 487). Transcutaneous electrical nerve stimulation (TENS, including interferential currents), electro-acupuncture (EA) and low level laser therapy (LLLT) offered clinically relevant pain relieving effects of 18.8 mm [95% CI: 9.6 to 28.1] (n = 414), 21.9 mm [95% CI: 17.3 to 26.5] (n = 73) and 17.7 mm [95% CI: 8.1 to 27.3] (n = 343) on VAS respectively versus placebo control. In a subgroup analysis of trials with assumed optimal doses, short-term efficacy increased to 22.2 mm [95% CI: 18.1 to 26.3] for TENS, and 24.2 mm [95% CI: 17.3 to 31.3] for LLLT on VAS. Follow-up data up to 12 weeks were sparse, but positive effects seemed to persist for at least 4 weeks after the course of LLLT, EA and TENS treatment was stopped. CONCLUSION: TENS, EA and LLLT administered with optimal doses in an intensive 2-4 week treatment regimen, seem to offer clinically relevant short-term pain relief for OAK

Conditional statistics of electron transport in interacting nanoscale conductors

Interactions between nanoscale semiconductor structures form the basis for charge detectors in the solid state. Recent experimental advances have demonstrated the on-chip detection of single electron transport through a quantum dot (QD). The discreteness of charge in units of e leads to intrinsic fluctuations in the electrical current, known as shot noise. To measure these single-electron fluctuations a nearby coherent conductor, called a quantum point contact (QPC), interacts with the QD and acts as a detector. An important property of the QPC charge detector is noninvasiveness: the system physically affects the detector, not visa-versa. Here we predict that even for ideal noninvasive detectors such as the QPC, when a particular detector result is observed, the system suffers an informational backaction, radically altering the statistics of transport through the QD as compared to the unconditional shot noise. We develop a theoretical model to make predictions about the joint current probability distributions and conditional transport statistics. The experimental findings reported here demonstrate the reality of informational backaction in nanoscale systems as well as a variety of new effects, such as conditional noise enhancement, which are in essentially perfect agreement with our model calculations. This type of switching telegraph process occurs abundantly in nature, indicating that these results are applicable to a wide variety of systems.Comment: 16 pages, 3 figures, to appear in Nature Physic

Contemporary medical television and crisis in the NHS

This article maps the terrain of contemporary UK medical television, paying particular attention to Call the Midwife as its centrepiece, and situating it in contextual relation to the current crisis in the NHS. It provides a historical overview of UK and US medical television, illustrating how medical television today has been shaped by noteworthy antecedents. It argues that crisis rhetoric surrounding healthcare leading up to the passing of the Health and Social Care Act 2012 has been accompanied by a renaissance in medical television. And that issues, strands and clusters have emerged in forms, registers and modes with noticeable regularity, especially around the value of affective labour, the cultural politics of nostalgia and the neoliberalisation of healthcare

Cross modal perception of body size in domestic dogs (Canis familiaris)

While the perception of size-related acoustic variation in animal vocalisations is well documented, little attention has been given to how this information might be integrated with corresponding visual information. Using a cross-modal design, we tested the ability of domestic dogs to match growls resynthesised to be typical of either a large or a small dog to size- matched models. Subjects looked at the size-matched model significantly more often and for a significantly longer duration than at the incorrect model, showing that they have the ability to relate information about body size from the acoustic domain to the appropriate visual category. Our study suggests that the perceptual and cognitive mechanisms at the basis of size assessment in mammals have a multisensory nature, and calls for further investigations of the multimodal processing of size information across animal species

Population Selection and Sequencing of Caenorhabditis elegans Wild Isolates Identifies a Region on Chromosome III Affecting Starvation Resistance

To understand the genetic basis of complex traits, it is important to be able to efficiently phenotype many genetically distinct individuals. In the nematode Caenorhabditis elegans, individuals have been isolated from diverse populations around the globe and whole-genome sequenced. As a result, hundreds of wild strains with known genome sequences can be used for genome-wide association studies (GWAS). However, phenotypic analysis of these strains can be laborious, particularly for quantitative traits requiring multiple measurements per strain. Starvation resistance is likely a fitness-proximal trait for nematodes, and it is related to metabolic disease risk in humans. However, natural variation in C. elegans starvation resistance has not been systematically characterized, and precise measurement of the trait is time-intensive. Here, we developed a population-selection-and-sequencing-based approach to phenotype starvation resistance in a pool of 96 wild strains. We used restriction site-associated DNA sequencing (RAD-seq) to infer the frequency of each strain among survivors in a mixed culture over time during starvation. We used manual starvation survival assays to validate the trait data, confirming that strains that increased in frequency over time are starvation-resistant relative to strains that decreased in frequency. Further, we found that variation in starvation resistance is significantly associated with variation at a region on chromosome III. Using a near-isogenic line (NIL), we showed the importance of this genomic interval for starvation resistance. This study demonstrates the feasibility of using population selection and sequencing in an animal model for phenotypic analysis of quantitative traits, documents natural variation of starvation resistance in C. elegans, and identifies a genomic region that contributes to such variation