Partial Reversion Research Articles

Competition and credit control: some personal reflections

The Bank of England's ‘consultative document’ on Competition and Credit Control (C&CC) was published on 14 May 1971. It was a landmark occasion, representing a decisive break with the prior system of maintaining direct controls over bank lending to the private sector; the intention was now to achieve the monetary authorities’ objectives of policy via the operation of market mechanisms, notably adjustments in interest rates and open market operations. Although the ‘credit control’ aspect was, over the next few years, notably less successful than the encouragement of competition amongst the banks (where the London clearing banks previously had maintained a restrictive cartel with the support of the authorities), nevertheless the direction of travel towards a more liberal, market-based system, remained, despite a partial reversion towards a direct control system in the guise of the ‘corset’, introduced at the end of 1973, and finally laid to rest in June 1980.

Complete Mitochondrial Complex I Deficiency Induces an Up-Regulation of Respiratory Fluxes That Is Abolished by Traces of Functional Complex I.

Complex I (NADH:ubiquinone oxidoreductase) is central to cellular NAD(+) recycling and accounts for approximately 40% of mitochondrial ATP production. To understand how complex I function impacts respiration and plant development, we isolated Arabidopsis (Arabidopsis thaliana) lines that lack complex I activity due to the absence of the catalytic subunit NDUFV1 (for NADH:ubiquinone oxidoreductase flavoprotein1) and compared these plants with ndufs4 (for NADH:ubiquinone oxidoreductase Fe-S protein4) mutants possessing trace amounts of complex I. Unlike ndufs4 plants, ndufv1 lines were largely unable to establish seedlings in the absence of externally supplied sucrose. Measurements of mitochondrial respiration and ATP synthesis revealed that compared with ndufv1, the complex I amounts retained by ndufs4 did not increase mitochondrial respiration and oxidative phosphorylation capacities. No major differences were seen in the mitochondrial proteomes, cellular metabolomes, or transcriptomes between ndufv1 and ndufs4. The analysis of fluxes through the respiratory pathway revealed that in ndufv1, fluxes through glycolysis and the tricarboxylic acid cycle were dramatically increased compared with ndufs4, which showed near wild-type-like fluxes. This indicates that the strong growth defects seen for plants lacking complex I originate from a switch in the metabolic mode of mitochondria and an up-regulation of respiratory fluxes. Partial reversion of these phenotypes when traces of active complex I are present suggests that complex I is essential for plant development and likely acts as a negative regulator of respiratory fluxes.

Enhancing Hydrogen Embrittlement Resistance of Lath Martensite by Introducing Nano-Films of Interlath Austenite

Partial reversion of interlath austenite nano-films is investigated as a potential remedy for hydrogen embrittlement susceptibility of martensitic steels. We conducted uniaxial tensile tests on hydrogen-free and pre-charged medium-Mn transformation-induced plasticity-maraging steels with different austenite film thicknesses. Mechanisms of crack propagation and microstructure interaction are quantitatively analyzed using electron channelling contrast imaging and electron backscatter diffraction, revealing a promising strategy to utilize austenite reversion for hydrogen-resistant martensitic steel design.

Type I Interferon Elevates Co-Regulatory Receptor Expression on CMV- and EBV-Specific CD8 T Cells in Chronic Hepatitis C.

Hepatitis C virus (HCV) readily sets up persistence in a large fraction of infected hosts. Mounting epidemiological and immunological evidence suggest that HCV’s persistence could influence immune responses toward unrelated pathogens and vaccines. Nonetheless, the fundamental contribution of the inflammatory milieu during persistent HCV infection in impacting immune cells specific for common pathogens such as CMV and EBV has not been fully studied. As the co-regulatory receptors PD-1, Tim-3, and 2B4 have all been shown to be vital in regulating CD8+ T cell function, we assessed their expression on CMV/EBV-specific CD8+ T cells from patients with chronic hepatitis C (CHC) and healthy controls ex vivo and upon stimulation with virus-specific peptides in vitro. Total and CMV/EBV-specific CD8+ T cells expressing PD-1, Tim-3, and 2B4 were highly enriched in patients with CHC compared to healthy individuals ex vivo. In vitro peptide stimulation further potentiated the differential co-regulatory receptor expression of PD-1, Tim-3, and 2B4, which then culminated in an enhanced functionality of CMV/EBV-specific CD8+ T cells in CHC patients. Comprehensively analyzing plasma cytokines between the two cohorts, we observed that not only was IFNα-2a dominant among 21 other inflammatory mediators elevated in CHC patients but it also correlated with PD-1 and Tim-3 expressions ex vivo. Importantly, IFNα-2a further caused upregulation of these markers upon in vitro peptide stimulation. Finally, we could prospectively study patients receiving novel IFN-free antiviral therapy. Here, we observed that treatment-induced clearance of HCV resulted in a partial reversion of the phenotype of CMV/EBV-specific CD8+ T cells in patients with CHC. These data reveal an alteration of the plasma concentrations of IFNα-2a together with other inflammatory mediators during CHC, which appeared to pervasively influence co-regulatory receptor expression on CMV/EBV-specific CD8+ T cells.

Fasting Enhances Pyroglutamyl Peptidase II Activity in Tanycytes of the Mediobasal Hypothalamus of Male Adult Rats.

Fasting down-regulates the hypothalamus-pituitary-thyroid (HPT) axis activity through a reduction of TRH synthesis in neurons of the parvocellular paraventricular nucleus of the hypothalamus (PVN). These TRH neurons project to the median eminence (ME), where TRH terminals are close to the cytoplasmic extensions of β2 tanycytes. Tanycytes express pyroglutamyl peptidase II (PPII), the TRH-degrading ectoenzyme that controls the amount of TRH that reaches the anterior pituitary. We tested the hypothesis that regulation of ME PPII activity is another mechanism by which fasting affects the activity of the HPT axis. Semiquantitative in situ hybridization histochemistry data indicated that PPII and deiodinase 2 mRNA levels increased in tanycytes after 48 hours of fasting. This increase was transitory, followed by an increase of PPII activity in the ME, and a partial reversion of the reduction in PVN pro-TRH mRNA levels and the number of TRH neurons detected by immunohistochemistry. In fed animals, adrenalectomy and corticosterone treatment did not change ME PPII activity 72 hours later. Methimazole-induced hypothyroidism produced a profound drop in tanycytes PPII mRNA levels, which was reverted by 3 days of treatment with T4. The activity of thyroliberinase, the serum isoform of PPII, was increased at most fasting time points studied. We conclude that delayed increases in both the ME PPII as well as the thyroliberinase activities in fasted male rats may facilitate the maintenance of the deep down-regulation of the HPT axis function, despite a partial reactivation of TRH expression in the PVN.

Structural significance of galectin design: impairment of homodimer stability by linker insertion and partial reversion by ligand presence.

Lectins translate information encoded in glycan chains of cellular glycoconjugates into bioeffects. The topological presentation of contact sites for cognate sugar binding is a crucial factor toward this end. To dissect the significance of such phylogenetically conserved properties, the design and engineering of non-natural variants are attractive approaches. Here, a homodimeric human lectin, i.e. adhesion/growth-regulatory galectin-1, is converted into a tandem-repeat display by introducing the 33-amino-acid linker of another family member (i.e. galectin-8). The yield of variant was reduced by about a third. This protein had ∼10-fold higher activity in hemagglutination. Nearly complete sequence determination by mass-spectrometric in-source decay and fingerprinting excluded the presence of any modifications. When (1)H-(15)N heteronuclear single-quantum coherence data on the (15)N-labeled variant and wild-type protein were compared, changes in chemical shifts, signal intensities and resonance multiplicities revealed reduction of stability of interfacial contacts between the lectin domains and an increase in inter-domain flexibility. When both binding sites in the variant were loaded with ligand, association of the two carbohydrate recognition domains was enhanced, corroborated by gel filtration. Dynamic changes in the spatial presentation of the two lectin domains in the context of a tandem-repeat display can alter counterreceptor targeting relative to the fixed positions found in the proto-type galectin homodimer.

DNA methylation profiling identifies two splenic marginal zone lymphoma subgroups with different clinical and genetic features

AbstractSplenic marginal zone lymphoma is a rare lymphoma. Loss of 7q31 and somatic mutations affecting the NOTCH2 and KLF2 genes are the commonest genomic aberrations. Epigenetic changes can be pharmacologically reverted; therefore, identification of groups of patients with specific epigenomic alterations might have therapeutic relevance. Here we integrated genome-wide DNA-promoter methylation profiling with gene expression profiling, and clinical and biological variables. An unsupervised clustering analysis of a test series of 98 samples identified 2 clusters with different degrees of promoter methylation. The cluster comprising samples with higher-promoter methylation (High-M) had a poorer overall survival compared with the lower (Low-M) cluster. The prognostic relevance of the High-M phenotype was confirmed in an independent validation set of 36 patients. In the whole series, the High-M phenotype was associated with IGHV1-02 usage, mutations of NOTCH2 gene, 7q31-32 loss, and histologic transformation. In the High-M set, a number of tumor-suppressor genes were methylated and repressed. PRC2 subunit genes and several prosurvival lymphoma genes were unmethylated and overexpressed. A model based on the methylation of 3 genes (CACNB2, HTRA1, KLF4) identified a poorer-outcome patient subset. Exposure of splenic marginal zone lymphoma cell lines to a demethylating agent caused partial reversion of the High-M phenotype and inhibition of proliferation.

ERK1/2 mediates glucose-regulated POMC gene expression in hypothalamic neurons.

Hypothalamic glucose-sensing neurons regulate the expression of genes encoding feeding-related neuropetides POMC, AgRP, and NPY - the key components governing metabolic homeostasis. AMP-activated protein kinase (AMPK) is postulated to be the molecular mediator relaying glucose signals to regulate the expression of these neuropeptides. Whether other signaling mediator(s) plays a role is not clear. In this study, we investigated the role of ERK1/2 using primary hypothalamic neurons as the model system. The primary neurons were differentiated from hypothalamic progenitor cells. The differentiated neurons possessed the characteristic neuronal cell morphology and expressed neuronal post-mitotic markers as well as leptin-regulated orexigenic POMC and anorexigenic AgRP/NPY genes. Treatment of cells with glucose dose-dependently increased POMC and decreased AgRP/NPY expression with a concurrent suppression of AMPK phosphorylation. In addition, glucose treatment dose-dependently increased the ERK1/2 phosphorylation. Blockade of ERK1/2 activity with its specific inhibitor PD98059 partially (approximately 50%) abolished glucose-induced POMC expression, but had little effect on AgRP/NPY expression. Conversely, blockade of AMPK activity with its specific inhibitor produced a partial (approximately 50%) reversion of low-glucose-suppressed POMC expression, but almost completely blunted the low-glucose-induced AgRP/NPY expression. The results indicate that ERK1/2 mediated POMC but not AgRP/NPY expression. Confirming the in vitro findings, i.c.v. administration of PD98059 in rats similarly attenuated glucose-induced POMC expression in the hypothalamus, but again had little effect on AgRP/NPY expression. The results are indicative of a novel role of ERK1/2 in glucose-regulated POMC expression and offer new mechanistic insights into hypothalamic glucose sensing.

A More Informative Unit Root Test for Driftless Time Series

We derive the driftless unit root test as a special limiting case of a particular type of an autoregressive test. The unit root and autoregressive tests are unified to create a comprehensive data mining tool for driftless time series. The proposed test is more informative than the current methodologies in that it can accommodate momentum, partial mean reversion, and full mean reversion in driftless time series. We discuss the design of the test, including the question whether the alternative hypotheses should include a drift.

Genetic suppression of plant development and chloroplast biogenesis via the Snowy Cotyledon 3 and Phytochrome B pathways.

Plant development is regulated by external and internal factors such as light and chloroplast development. A revertant of the Arabidopsis thaliana (L.) Heyhn. chloroplast biogenesis mutant snowy cotyledon 3 (sco3-1) was isolated partially recovering the impaired chloroplast phenotype. The mutation was identified in the Phytochrome B (PhyB) gene and is a result of an amino acid change within the PAS repeat domain required for light-induced nuclear localisation. An independent phyB-9 mutation was crossed into sco3-1 mutants, resulting in the same partial reversion of sco3-1. Further analysis demonstrated that SCO3 and PhyB influence the greening process of seedlings and rosette leaves, embryogenesis, rosette formation and flowering. Interestingly, the functions of these proteins are interwoven in various ways, suggesting a complex genetic interaction. Whole-transcriptome profiling of sco3-1phyB-9 indicated that a completely distinct set of genes was differentially regulated in the double mutant compared with the single sco3-1 or phyB-9 mutants. Thus, we hypothesise that PhyB and SCO3 genetically suppress each other in plant and chloroplast development.

Nanolaminate transformation-induced plasticity–twinning-induced plasticity steel with dynamic strain partitioning and enhanced damage resistance

Conventional martensitic steels have limited ductility due to insufficient microstructural strain-hardening and damage resistance mechanisms. It was recently demonstrated that the ductility and toughness of martensitic steels can be improved without sacrificing the strength, via partial reversion of the martensite back to austenite. These improvements were attributed to the presence of the transformation-induced plasticity (TRIP) effect of the austenite phase, and the precipitation hardening (maraging) effect in the martensitic matrix. However, a full micromechanical understanding of this ductilizing effect requires a systematic investigation of the interplay between the two phases, with regards to the underlying deformation and damage micromechanisms. For this purpose, in this work, a Fe–9Mn–3Ni–1.4Al–0.01C (mass%) medium-Mn TRIP maraging steel is produced and heat-treated under different reversion conditions to introduce well-controlled variations in the austenite–martensite nanolaminate microstructure. Uniaxial tension and impact tests are carried out and the microstructure is characterized using scanning and transmission electron microscopy based techniques and post mortem synchrotron X-ray diffraction analysis. The results reveal that (i) the strain partitioning between austenite and martensite is governed by a highly dynamical interplay of dislocation slip, deformation-induced phase transformation (i.e. causing the TRIP effect) and mechanical twinning (i.e. causing the twinning-induced plasticity effect); and (ii) the nanolaminate microstructure morphology leads to enhanced damage resistance. The presence of both effects results in enhanced strain-hardening capacity and damage resistance, and hence the enhanced ductility.

Abstract 5296: The role of SOCS-1 in stimulating melanoma development through growth factor receptors and MAPK pathways

Abstract Knowledge on the regulatory pathways involved in melanoma development and progression has advanced significantly in recent years. It is now recognized that multiple signaling pathways that affect motility, growth control, invasion, metabolism, cytokine release and the ability to escape the immune response, regulate melanoma development. Silencing of SOCS-1 protein, a negative regulator of Jak/Stat pathway, leads to partial reversion of the tumorigenic phenotype of B16F10-Nex2 melanoma cells. SOCS-1 silencing with shRNAi inhibits in vitro growth by cell cycle regulation with S phase arrest and increased size of cells and nuclei. It also inhibited tumor cell migration and invasion. Down-regulation of SOCS-1 decreased the expression of epidermal growth factor receptor (mainly the phosphorylated-R), Ins-Rα, and fibroblast growth factor receptors. Based on the results of SOCS-1 silencing, the present work aims at analyzing the expression of proteins relevant to tumor development, searching for signaling pathways related with SOCS-1. A protein microarray analysis of murine melanoma cells silenced for SOCS-1 by shRNAi SOCS-1 lentivirus transduction was undertaken using as controls, cells transduced with the empty vector. Among the 614 differentially expressed genes some cytokine/growth factor receptors were down regulated, e.g. c-kit, met and EphA3. Western blotting of B16 shR-SOCS-1 cell extracts showed a significant decrease in the expression of these receptors, indicating that SOCS-1 positively regulates the MAPK pathways in these cells. We analyzed the main MAPK pathways that were up regulated in melanoma and observed a decrease in the phosphorylation of mediators of ERK1/2 and p38 pathways and of STAT3 (S727). These results demonstrate that SOCS-1 can play an important role in tumor development and progression up regulating a number of growth factor receptors in murine melanoma cells. Interestingly, p-CREB (S133) was up regulated in the SOCS-1-deficient B16F10-Nex2 cells. In vivo experiments showed that using a prophylactic protocol, the subcutaneous immunization of syngeneic mice with B16 shR-SOCS-1 viable cells, rendered a protective effect against subcutaneously grafted and metastatic murine melanoma, with significant reduction in tumor growth and metastates in the lungs. A flow cytometry assay showed decreased expression of PD-L1 at the surface of B16 shR-SOCS-1 cells. This might explain the protective effect of subcutaneous immunization with these cells, rather than with wild-type B16F10-Nex2 cells that overexpress PD-L1, which negatively regulates T-cell immune response. Down regulation of PD-L1 is compatible with inactive ERK. The present results show the important role of SOCS-1 in murine melanoma stimulating cell growth and migration, allowing for the invasive phenotype. Citation Format: Rodrigo Berzaghi, Felipe V. Pereira, Vera S.C. Maia, Jorge B. Scutti, Luiz R. Travassos. The role of SOCS-1 in stimulating melanoma development through growth factor receptors and MAPK pathways. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5296. doi:10.1158/1538-7445.AM2014-5296

Gene expression profiling of peripheral blood mononuclear cells during treatment with a gene-modified allogeneic tumor cell vaccine in advanced renal cell cancer: tumor-induced immunosuppression and a possible role for NF-κB.

Tumor-induced immunosuppression remains a major challenge for immunotherapy of cancer patients. To further elucidate why an allogeneic gene-modified [interleukin-7 (IL-7)/CD80-cotransfected] renal cell cancer (RCC) vaccine failed to induce clinically relevant TH-1-polarized immune responses, peripheral blood mononuclear cells from enrolled study patients were analyzed by gene expression profiling (GEP) both prior and after vaccination. At baseline before vaccination, a profound downregulation of gene signatures associated with antigen presentation, immune response/T cells, cytokines/chemokines and signaling/transcription factors was observed in RCC patients as compared to healthy controls. Vaccination led to a partial reversion of preexisting immunosuppression, however, GEP indicated that an appropriate TH-1 polarization could not be achieved. Most interestingly, our results suggest that the nuclear factor-kappa B signaling pathway might be involved in the impairment of immunological responsiveness and the observed TH-2 deviation. In summary, our data suggest that GEP might be a powerful tool for the prediction of immunosuppression and the monitoring of immune responses within immunotherapy trials.

Abstract 3043: Mesenchymal phenoptype of metastasizing primary human colorectal TIC is maintained through epigenetic silencing of miR-200

Abstract Metastasis formation is the most common cause of colorectal cancer (CRC) related death. How cancer cells disseminate from the primary tumor, gain access to blood and lymphatic vessels and seed to distant organs is not fully understood. To gain deeper mechanistic insights into metastasis formation, we developed a metastasis xenotransplantation model for primary human colorectal cancer cells. Patient (n=12) derived tumor-initiating cells (TIC) were enriched in spheroid cultures and subsequently transplanted into the kidney capsule of immunodeficient NOD/SCID-IL2RGnull (NSG) mice. Importantly, cultures derived from 3 distinct patients frequently metastasized into the murine liver and spleen, whereas spheroids derived from all other patients (n=9) never did. Compared to non-metastasizing spheroids, metastasizing spheroids strongly expressed mesenchymal markers (e.g. Vimentin and N-cadherin), whereas epithelial and colonic differentiation markers (e.g. E-cadherin, Trefoil factor 3, Defensin alpha 5, Keratin-8, -18 -20) were down-regulated suggesting that metastasizing primary patient derived CRC spheroids may have passed through an epithelial to mesenchymal transition (EMT). As the miR-200 family has been shown to support an epithelial phenotype and has been implicated in the process of EMT in tumor cells, we analyzed miRNA expression in metastasizing versus non-metastasizing spheroid cultures. Interestingly, metastasizing spheroids strongly down-regulated the miR-200 clusters miR-200a/-200b/-429 and miR-200c/-141 as well as miR-194 and miR-203. To further understand the mechanism of deregulated gene- and miRNA expression in metastasizing spheroids, we evaluated the DNA methylation status of miRNA promoters. In contrast to non-metastasizing spheroid cultures, metastasizing spheroids showed pronounced DNA methylation within the miR-200 promoter regions, indicating that miR-200 expression in primary metastasizing human colorectal cancer spheroids is suppressed through epigenetic mechanisms. Forced overexpression of both miR-200 clusters in metastasizing spheroids restored expression of epithelial genes like E-Cadherin and Keratin-8 and reduced expression of the mesenchymal markers Vimentin and N-cadherin. Moreover, incubation with low dose 5-aza-2′-deoxycytidine increased the expression of epithelial cell adhesion molecule (EpCAM) in metastasizing spheroids, indicating a partial reversion of the mesenchymal phenotype by demethylating agents. In summary, our findings indicate that metastasizing primary human CRC spheroids are epigenetically fixed in a mesenchymal state. This model allows further dissecting and understanding mechanisms of EMT and metastasis formation in human CRC thereby providing the basis for the development of future therapeutic intervention strategies against metastasizing human colorectal cancer. Citation Format: Christopher M. Hoffmann, Klara M. Giessler, Claudia R. Ball, Taronish D. Dubash, Sebastian M. Dieter, Sarah Bergmann, Wilko Weichert, Christof Von Kalle, Martin Schneider, Constance Baer, Christoph Plass, Manfred Schmidt, Hanno Glimm. Mesenchymal phenoptype of metastasizing primary human colorectal TIC is maintained through epigenetic silencing of miR-200. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3043. doi:10.1158/1538-7445.AM2014-3043

Abstract 5297: Role of p38 MAPK signaling pathway in the inhibition of breast tumor progression induced by Glypican-3 (GPC3)

Abstract Glypican-3 (GPC3) is expressed in normal mammary tissues, but it disappears in tumors. We have transfected the GPC3 gene into murine mammary adenocarcinoma LM3 cells, demonstrating that this proteoglycan acts as a metastasis suppressor. GPC3 reexpressing clones are less metastatic in vivo, showing reduced migration and increased susceptibility to apoptosis in vitro. In relation to GPC3 signaling pathway, we have reported that LM3-GPC3 cells exhibit an inhibition of Akt and canonical Wnt pathways, while they show an activation of non-canonical Wnt and p38 signaling. The aim of this work was to study if the effects of GPC3 on breast tumor progression could be due to p38 activation. LM3-GPC3 or LM3-vector cells were inoculated s.c. into female BALB/c mice. One day later, the p38 inhibitor SB203580 or the vehicle DMSO, were injected i.p. into LM3-GPC3 cells-bearing mice, every 24 h for 10 days. Daily, we recorded the largest and smallest diameter of tumors. Thirty days post-inoculation, mice were killed. We evaluated primary tumor invasiveness behavior by macroscopic examination and histopathological study. We also analyze the spontaneous lungs metastasis, through the counting of macroscopic nodules. LM3-GPC3 and LM3-vector clones generated s.c. tumors showing similar latency and tumorigenic capacity, irrespective of SB203580 treatment (Latency in days, Md [Rg]: 8 [8-10]. Tumorigenicity: 100%). LM3-GPC3 tumors presented a growth rate higher than LM3-vector, while tumors treated with SB203580 grew faster (mm3/day: 17.6±1.9 -GPC3; 15.8±0.9 -vector, 28.2±1.6 -GPC3+SB203580; p<0.05). On the other hand, while only about 30% of LM3-GPC3 tumors showed macroscopic invasion with ulceration compared to 100% of LM3-vector ones, the SB203580 treatment induced an increase in LM3-GPC3 tumors ulceration (reaching 100% affected tumors). This was confirmed through hematoxylin-eosin staining and microscopic examination. We observed only 40% of LM3-GPC3 tumors with occasional invasion of the muscle and dermis, in contrast to 100% of LM3-vector tumors with muscle, dermis and epidermis invasion. The SB203580 treatment was able to revert the GPC3 inhibitory effect on local invasion, inducing invasion of the muscle, dermis and epidermis in all cases. We observed that all tumors generated only lung spontaneous metastasis. While about 90% of LM3-vector tumors-bearing mice developed metastasis, there were no LM3-GPC3 tumors-bearing mice that did it. However, the treatment with p38 inhibitor induced a partial reversion of the GPC3 effect, showing metastasis in 60% of the animals. In sum, we have confirmed that GPC3 acts as metastasis suppressor in the present breast cancer model. Also, we demonstrated that GPC3 would be able to inhibit invasiveness and metastatic capacities trough p38 activation. We trust that our results could be the bases to explore new molecular targets against metastatic disease. Citation Format: Rocio S. Tascon, Lilian F. Castillo, Fernanda Roca, Elisa Bal de Kier Joffé, Maria G. Peters. Role of p38 MAPK signaling pathway in the inhibition of breast tumor progression induced by Glypican-3 (GPC3). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5297. doi:10.1158/1538-7445.AM2014-5297

T-wave reversion in pediatric patients during exercise stress testing.

T-wave inversion in lateral electrocardiogram (ECG) leads (II, III, aVF, V4 -V6 ) is suspicious of cardiac pathology in pediatric patients, though many are found to have structurally normal hearts. The purpose of this study is to evaluate T-wave response during exercise stress testing (EST) in pediatric patients with structurally normal hearts and lateral-lead T-wave inversion on resting ECG. An IRB-approved, retrospective review of EST databases at two centers identified patients with lateral-lead T-wave inversion on resting ECG. Inclusion criteria were normal exam and echocardiogram, absence of anginal chest pain, and age <18 years. All patients underwent treadmill or cycle ergometer EST. Data recorded included demographics, echocardiogram results, baseline ECG, EST method, peak heart rate and metabolic equivalents (METs), and heart rate and METs at T-wave reversion. T-wave reversion was considered complete if T-waves reverted in all leads, partial if reversion occurred in only some leads, and none if no reversion occurred. The search identified 14 patients: nine females and five males (10 Caucasians and four African Americans) and an average age of 16 (range 12-18) years. Complete T-wave reversion occurred in 11 (79%) patients, partial in two (14%), and none in one (7%). Reversion occurred in both genders, ethnicities, and EST methods. No complications occurred during EST; no adverse outcomes occurred during 2-year follow-up. EST in pediatric patients with lateral-lead T-wave inversion on resting ECG and structurally and functionally normal hearts resulted in either complete or partial T-wave reversion in the vast majority of patients.

Platelet-rich plasma induces mixed osteogenic/osteoclastogenic phenotype in osteosarcoma SaOS-2 cells: role of TGF-beta.

Platelet-rich plasma (PRP) is widely used to promote tissue repair and accelerate osteogenesis, but there is no agreement about its mechanism of action. We characterized the modulatory effect of PRP on the in vitro osteoblast model SaOS-2, by using cell motility/chemoattraction and osteogenesis/mineralization assays, and a series of osteogenic/ osteoclastogenic genomic markers. Scratch wound assay showed that PRP stimulates cell motility, while transwell assay revealed a strong chemoattraction. Alkaline phosphatase (ALP) and alizarin red-S assays showed that PRP induces slight, but significant, stimulations of ALP activity and mineralization. The TGF-β inhibitor SB431542 reversed these effects, showing a main role for TGF-β1 released by PRP. Analyses of gene expression by qRT-PCR, showed the upregulation of osteocalcin, osteopontin, osteoprotegerin, receptor activator of NFκB (RANK), and runt-related transcription factor 2 (RUNX2) genes, with a total reversion by SB431542 for osteoprotegerin and RANK, and a partial reversion for ostecalcin, osteopontin, and RUNX2. The use of PCR array technique revealed the upregulation of the cathepsin K gene. These data show that PRP induces the development of mixed osteogenic/osteoclastogenic traits in the SaOS-2 model. Such a behavior may favour in vivo bone resorption and reconstitution at post-surgery or post-traumatic sites.

What Kind of ‘Big Government’ is the Big Society? A Reply to Bulley and Sokhi-Bulley

Research Highlights and Abstract This article Contributes to the debates applying Foucauldian theory to contemporary British Politics and invigorates the debate through a discussion with Bulley and Sokhi Bulley Develops understandings of contemporary British Politics under the Coalition government, particularly in light of the ‘Big Society’ project. Compares, through a Foucauldian framework, the differences and similarities between the New Labour (1997–2010) and Coalition (2010–) Governments Ultimately argues that the Coalition Government is demonstrative of a hybrid of the neo-liberal governmentality typical of the New Labour governments and a partial reversion to a more rudimentary Thatcherite form of neo-liberal governmentality. This article is a reply to Bulley and Sokhi-Bulley's recent article on the Big Society. We put forward two main criticisms of Bulley and Sokhi-Bulley's governmentality-focused approach in our alternative reading of the Big Society. Firstly, we argue that, given the ethopolitical strategies Bulley and Sokhi-Bulley focus their attention on are unlikely to produce the kind of transformation in the ethical outlook of citizens they suppose, the real historical significance of the Big Society must lie elsewhere. Secondly, we argue that Bulley and Sokhi-Bulley overlook the lines of continuity and discontinuity linking the Big Society to the forms of neo-liberal governmentality that have preceded it in British politics. In the final section of the article, we argue that the Cameron project amounts to both a partial continuation of the type of neo-liberal governmental rationality characteristic of the New Labour project and a partial reversion to a more rudimentary Thatcherite form of neo-liberal governmentality.

The Mitogen-activated Protein (MAP) Kinases p38 and Extracellular Signal-regulated Kinase (ERK) Are Involved in Hepatocyte-mediated Phenotypic Switching in Prostate Cancer Cells

The greatest challenge for the seeding of cancer in metastatic sites is integration into the ectopic microenvironment despite the lack of an orthotopic supportive environment and presence of pro-death signals concomitant with a localized "foreign-body" inflammatory response. In this metastatic location, many carcinoma cells display a reversion of the epithelial-to-mesenchymal transition that marks dissemination in the primary tumor mass. This mesenchymal to epithelial reverting transition (MErT) is thought to help seeding and colonization by protecting against cell death. We have previously shown that hepatocyte coculture induces the re-expression of E-cadherin via abrogation of autocrine EGFR signaling pathway in prostate cancer (PCa) cells and that this confers a survival advantage. Herein, we show that hepatocytes educate PCa to undergo MErT by modulating the activity of p38 and ERK1/2. Hepatocytes inhibited p38 and ERK1/2 activity in prostate cancer cells, which allowed E-cadherin re-expression. Introduction of constitutively active MEK6 and MEK1 to DU145 cells cocultured with hepatocytes abrogated E-cadherin re-expression. At least a partial phenotypic reversion can be achieved by suppression of p38 and ERK1/2 activation in DU145 cells even in the absence of hepatocytes. Interestingly, these mitogen-activated protein kinase activities were also triggered by re-expressed E-cadherin leading to p38 and ERK1/2 activity in PCa cells; these signals provide protection to PCa cells upon challenge with chemotherapy and cell death-inducing cytokines. We propose that distinct p38/ERK pathways are related to E-cadherin levels and function downstream of E-cadherin allowing, respectively, for hepatocyte-mediated MErT and tumor cell survival in the face of death signals.

Transcriptional and hormonal regulation of petal and stamen development by STAMENLESS, the tomato (Solanum lycopersicum L.) orthologue to the B-class APETALA3 gene.

Four B-class MADS box genes specify petal and stamen organ identities in tomato. Several homeotic mutants affected in petal and stamen development were described in this model species, although the causal mutations have not been identified for most of them. In this study we characterized a strong stamenless mutant in the tomato Primabel cultivar (sl-Pr), which exhibited homeotic conversion of petals into sepals and stamens into carpels and we compared it with the stamenless mutant in the LA0269 accession (sl-LA0269). Genetic complementation analysis proved that both sl mutants were allelic. Sequencing revealed point mutations in the coding sequence of the Tomato APETALA3 (TAP3) gene of the sl-Pr genome, which lead to a truncated protein, whereas a chromosomal rearrangement in the TAP3 promoter was detected in the sl-LA0269 allele. Moreover, the floral phenotype of TAP3 antisense plants exhibited identical homeotic changes to sl mutants. These results demonstrate that SL is the tomato AP3 orthologue and that the mutant phenotype correlated to the SL silencing level. Expression analyses showed that the sl-Pr mutation does not affect the expression of other tomato B-class genes, although SL may repress the A-class gene MACROCALYX. A partial reversion of the sl phenotype by gibberellins, gene expression analysis, and hormone quantification in sl flowers revealed a role of phytohormones in flower development downstream of the SL gene. Together, our results indicated that petal and stamen identity in tomato depends on gene-hormone interactions, as mediated by the SL gene.