268 research outputs found

    Protein Kinase R Modulates c-Fos and c-Jun Signaling to Promote Proliferation of Hepatocellular Carcinoma with Hepatitis C Virus Infection

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    Double-stranded RNA-activated protein kinase R (PKR) is known to be upregulated by hepatitis C virus (HCV) and overexpressed in hepatocellular carcinoma (HCC). However, the precise roles of PKR in HCC with HCV infection remain unclear. Two HCV replicating cell lines (JFH-1 and H77s), generated by transfection of Huh7.5.1 cells, were used for experiments reported here. PKR expression was modulated with siRNA and a PKR expression plasmid, and cancer-related genes were assessed by real-time PCR and Western blotting; cell lines were further analyzed using a proliferation assay. Modulation of genes by PKR was also assessed in 34 human HCC specimens. Parallel changes in c-Fos and c-Jun gene expression with PKR were observed. Levels of phosphorylated c-Fos and c-Jun were upregulated by an increase of PKR, and were related to levels of phosphorylated JNK1 and Erk1/2. DNA binding activities of c-Fos and c-Jun also correlated with PKR expression, and cell proliferation was dependent on PKR-modulated c-Fos and c-Jun expression. Coordinate expression of c-Jun and PKR was confirmed in human HCC specimens with HCV infection. PKR upregulated c-Fos and c-Jun activities through activation of Erk1/2 and JNK1, respectively. These modulations resulted in HCC cell proliferation with HCV infection. These findings suggest that PKR-related proliferation pathways could be an attractive therapeutic target

    The antimicrobial lysine-peptoid hybrid LP5 inhibits DNA replication and induces the SOS response in Staphylococcus aureus

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    BACKGROUND: The increase in antibiotic resistant bacteria has led to renewed interest in development of alternative antimicrobial compounds such as antimicrobial peptides (AMPs), either naturally-occurring or synthetically-derived. Knowledge of the mode of action (MOA) of synthetic compounds mimicking the function of AMPs is highly valuable both when developing new types of antimicrobials and when predicting resistance development. Despite many functional studies of AMPs, only a few of the synthetic peptides have been studied in detail. RESULTS: We investigated the MOA of the lysine-peptoid hybrid, LP5, which previously has been shown to display antimicrobial activity against Staphylococcus aureus. At concentrations of LP5 above the minimal inhibitory concentration (MIC), the peptoid caused ATP leakage from bacterial cells. However, at concentrations close to the MIC, LP5 inhibited the growth of S. aureus without ATP leakage. Instead, LP5 bound DNA and inhibited macromolecular synthesis. The binding to DNA also led to inhibition of DNA gyrase and topoisomerase IV and caused induction of the SOS response. CONCLUSIONS: Our data demonstrate that LP5 may have a dual mode of action against S. aureus. At MIC concentrations, LP5 binds DNA and inhibits macromolecular synthesis and growth, whereas at concentrations above the MIC, LP5 targets the bacterial membrane leading to disruption of the membrane. These results add new information about the MOA of a new synthetic AMP and aid in the future design of synthetic peptides with increased therapeutic potential

    Vortex State and Field-Angle Resolved Specific Heat Oscillation for H // ab in d-Wave Superconductors

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    When magnetic field is applied parallel to the ab plane in d_{x^2-y^2}-wave superconductors, the transition of stable vortex lattice structure, spatial structure of local density of states, and specific heat oscillation by rotation of magnetic field orientation are investigated by quantitative calculations based on the selfconsistent Eilenberger theory. We estimate how the vortex state changes depending on the relative angle between the node-direction of the superconducting gap and magnetic field orientation. To reproduce the sign-change of specific heat oscillation observed in CeCoIn_5, our study is done by including strong paramagnetic effect. The quantitative theoretical calculations give decisive information to analyze the experimental data on the field-angle dependence, and establish the angle-resolved specific heat experiment as a spectroscopic means to identify the node-position of the superconducting gap.Comment: 9 pages, 13 figure

    Lenvatinib versus Sorafenib as first-line treatment in hepatocellular carcinoma: A multi-institutional matched case-control study

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    Background: Advanced Hepatocarcinoma (HCC) is an important health problem worldwide. Recently, the REFLECT trial demonstrated the non-inferiority of Lenvatinib compared to Sorafenib in I line setting, thus leading to the approval of new first-line standard of care, along with Sorafenib. Aims and methods: With aim to evaluate the optimal choice between Sorafenib and Lenvatinib as primary treatment in clinical practice, we performed a multicentric analysis with the propensity score matching on 184 HCC patients. Results: The median overall survival (OS) were 15.2 and 10.5 months for Lenvatinib and Sorafenib arm, respectively. The median progression-free survival (PFS) was 7.0 and 4.5 months for Lenvatinib and Sorafenib arm, respectively. Patients treated with Lenvatinib showed a 36% reduction of death risk (p = 0.0156), a 29% reduction of progression risk (p = 0.0446), a higher response rate (p < 0.00001) and a higher disease control rate (p = 0.002). Sorafenib showed to be correlated with more hand-foot skin reaction and Lenvatinib with more hypertension and fatigue. We highlighted the prognostic role of Barcelona Clinic Liver Cancer (BCLC) stage, Eastern Cooperative Oncology Group Performance Status (ECOG-PS), bilirubin, alkaline phosphatase and eosinophils for Sorafenib. Conversely, albumin, aspartate aminotransferase (AST), alkaline phosphatase and Neutrophil-Lymphocyte Ratio (NLR) resulted prognostic in Lenvatinib arm. Finally, we highlighted the positive predictive role of albumin > Normal Value (NV), ECOG > 0, NLR < 3, absence of Hepatitis C Virus positivity, and presence of portal vein thrombosis in favor of Lenvatinib arm. Eosinophil < 50 and ECOG > 0 negatively predicted the response to Sorafenib. Conclusion: SLenvatinib showed to better perform in a real-word setting compared to Sorafenib. More researches are needed to validate the predictor factors of response to Lenvatinib rather than Sorafenib

    Advanced Instrumentation of Frequency Modulation AFM for Subnanometer-Scale 2D/3D Measurements at Solid-Liquid Interfaces

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    Since the first demonstration of true atomic-resolution imaging by frequency modulation atomic force microscopy (FM-AFM) in liquid, the method has been used for imaging subnanometer-scale structures of various materials including minerals, biological systems and other organic molecules. Rencetly, there have been further advancements in theFM-AFMinstrumentation. Three-dimensional (3D) force measurement techniques are proposed for visualizing 3D hydration structures formed at a solid-liquid interface. Thesemethods further enabled to visualize 3D distributions of flexible surface structures at interfaces between soft materials andwater. Furthermore, the fundamental performance such as force sensitivity and operation speed have been significantly improved using a small cantilever and high-speed phase detector. These technical advancements enabled direct visualization of atomic-scale interfacial phenomena at 1 frame/s. In this chapter, these recent advancements in the FM-AFM instrumentation and their applications to the studies on various interfacial phenomena are presented. © Springer International Publishing Switzerland 201

    Nonalcoholic steatohepatitis in hepatocarcinoma: new insights about its prognostic role in patients treated with lenvatinib

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    Background: Hepatocellular carcinoma (HCC) treatment remains a big challenge in the field of oncology. The liver disease (viral or not viral) underlying HCC turned out to be crucial in determining the biologic behavior of the tumor, including its response to treatment. The aim of this analysis was to investigate the role of the etiology of the underlying liver disease in survival outcomes. Patients and methods: We conducted a multicenter retrospective study on a large cohort of patients treated with lenvatinib as first-line therapy for advanced HCC from both Eastern and Western institutions. Univariate and multivariate analyses were performed. Results: Among the 1232 lenvatinib-treated HCC patients, 453 (36.8%) were hepatitis C virus positive, 268 hepatitis B virus positive (21.8%), 236 nonalcoholic steatohepatitis (NASH) correlate (19.2%) and 275 had other etiologies (22.3%). The median progression-free survival (mPFS) was 6.2 months [95% confidence interval (CI) 5.9-6.7 months] and the median overall survival (mOS) was 15.8 months (95% CI 14.9-17.2 months). In the univariate analysis for OS NASH-HCC was associated with longer mOS [22.2 versus 15.1 months; hazard ratio (HR) 0.69; 95% CI 0.56-0.85; P = 0.0006]. In the univariate analysis for PFS NASH-HCC was associated with longer mPFS (7.5 versus 6.5 months; HR 0.84; 95% CI 0.71-0.99; P = 0.0436). The multivariate analysis confirmed NASH-HCC (HR 0.64; 95% CI 0.48-0.86; P = 0.0028) as an independent prognostic factor for OS, along with albumin–bilirubin (ALBI) grade, extrahepatic spread, neutrophil-to-lymphocyte ratio, portal vein thrombosis, Eastern Cooperative Oncology Group (ECOG) performance status and alpha-fetoprotein. An interaction test was performed between sorafenib and lenvatinib cohorts and the results highlighted the positive predictive role of NASH in favor of the lenvatinib arm (P = 0.0047). Conclusion: NASH has been identified as an independent prognostic factor in a large cohort of patients with advanced HCC treated with lenvatinib, thereby suggesting the role of the etiology in the selection of patients for tyrosine kinase treatment. If validated, this result could provide new insights useful to improve the management of these patients

    New susceptibility and resistance HLA-DP alleles to HBV-related diseases identified by a trans-ethnic association study in Asia

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    Previous studies have revealed the association between SNPs located on human leukocyte antigen (HLA) class II genes, including HLA-DP and HLA-DQ, and chronic hepatitis B virus (HBV) infection, mainly in Asian populations. HLA-DP alleles or haplotypes associated with chronic HBV infection or disease progression have not been fully identified in Asian populations. We performed trans-ethnic association analyses of HLA-DPA1, HLA-DPB1 alleles and haplotypes with hepatitis B virus infection and disease progression among Asian populations comprising Japanese, Korean, Hong Kong, and Thai subjects. To assess the association between HLA-DP and chronic HBV infection and disease progression, we conducted high-resolution (4-digit) HLA-DPA1 and HLA-DPB1 genotyping in a total of 3,167 samples, including HBV patients, HBV-resolved individuals and healthy controls. Trans-ethnic association analyses among Asian populations identified a new risk allele HLA-DPB1*09 ratio 01 (P = 1.36 x 10(-6); OR= 1.97; 95% CI, 1.50-2.59) and a new protective allele DPB1*02 ratio 01 (P = 5.22 x 10(-6); OR = 0.68; 95% CI, 0.58-0.81) to chronic HBV infection, in addition to the previously reported alleles. Moreover, DPB1*02 ratio 01 was also associated with a decreased risk of disease progression in chronic HBV patients among Asian populations (P = 1.55 x 10(-7); OR = 0.50; 95% CI, 0.39-0.65). Trans-ethnic association analyses identified Asian-specific associations of HLA-DP alleles and haplotypes with HBV infection or disease progression. The present findings will serve as a base for future functional studies of HLA-DP molecules in order to understand the pathogenesis of HBV infection and the development of hepatocellular carcinoma.published_or_final_versio

    Tumor Necrosis Factor α Inhibits Expression of the Iron Regulating Hormone Hepcidin in Murine Models of Innate Colitis

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    Background: Abnormal expression of the liver peptide hormone hepcidin, a key regulator of iron homeostasis, contributes to the pathogenesis of anemia in conditions such as inflammatory bowel disease (IBD). Since little is known about the mechanisms that control hepcidin expression during states of intestinal inflammation, we sought to shed light on this issue using mouse models. Methodology/Principal Findings: Hepcidin expression was evaluated in two types of intestinal inflammation caused by innate immune activation—dextran sulfate sodium (DSS)-induced colitis in wild-type mice and the spontaneous colitis occurring in T-bet/Rag2-deficient (TRUC) mice. The role of tumor necrosis factor (TNF) α\alpha was investigated by in vivo neutralization, and by treatment of a hepatocyte cell line, as well as mice, with the recombinant cytokine. Expression and activation of Smad1, a positive regulator of hepcidin transcription, were assessed during colitis and following administration or neutralization of TNFα\alpha. Hepcidin expression progressively decreased with time during DSS colitis, correlating with changes in systemic iron distribution. TNFα\alpha inhibited hepcidin expression in cultured hepatocytes and non-colitic mice, while TNFα\alpha neutralization during DSS colitis increased it. Similar results were obtained in TRUC mice. These effects involved a TNFα\alpha-dependent decrease in Smad1 protein but not mRNA. Conclusions/Significance: TNFα\alpha inhibits hepcidin expression in two distinct types of innate colitis, with down-regulation of Smad1 protein playing an important role in this process. This inhibitory effect of TNFα\alpha may be superseded by other factors in the context of T cell-mediated colitis given that in the latter form of intestinal inflammation hepcidin is usually up-regulated
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