Sphingosine kinase 1/S1P receptor signaling axis is essential for cellular uptake of Neisseria meningitidis in brain endothelial cells

Invasion of brain endothelial cells (BECs) is central to the pathogenicity of Neisseria meningitidis infection. Here, we established a key role for the bioactive sphingolipid sphingosine-1-phosphate (S1P) and S1P receptor (S1PR) 2 in the uptake process. Quantitative sphingolipidome analyses of BECs infected with N. meningitidis revealed elevated S1P levels, which could be attributed to enhanced expression of the enzyme sphingosine kinase 1 and its activity. Increased activity was dependent on the interaction of meningococcal type IV pilus with the endothelial receptor CD147. Concurrently, infection led to increased expression of the S1PR2. Blocking S1PR2 signaling impaired epidermal growth factor receptor (EGFR) phosphorylation, which has been shown to be involved in cytoskeletal remodeling and bacterial endocytosis. Strikingly, targeting S1PR1 or S1PR3 also interfered with bacterial uptake. Collectively, our data support a critical role of the SphK/S1P/S1PR axis in the invasion of N. meningitidis into BECs, defining a potential target for adjuvant therapy

Sole-Search: an integrated analysis program for peak detection and functional annotation using ChIP-seq data

Next-generation sequencing is revolutionizing the identification of transcription factor binding sites throughout the human genome. However, the bioinformatics analysis of large datasets collected using chromatin immunoprecipitation and high-throughput sequencing is often a roadblock that impedes researchers in their attempts to gain biological insights from their experiments. We have developed integrated peak-calling and analysis software (Sole-Search) which is available through a user-friendly interface and (i) converts raw data into a format for visualization on a genome browser, (ii) outputs ranked peak locations using a statistically based method that overcomes the significant problem of false positives, (iii) identifies the gene nearest to each peak, (iv) classifies the location of each peak relative to gene structure, (v) provides information such as the number of binding sites per chromosome and per gene and (vi) allows the user to determine overlap between two different experiments. In addition, the program performs an analysis of amplified and deleted regions of the input genome. This software is web-based and automated, allowing easy and immediate access to all investigators. We demonstrate the utility of our software by collecting, analyzing and comparing ChIP-seq data for six different human transcription factors/cell line combinations

Sphingosine kinase 1/S1P receptor signaling axis is essential for cellular uptake of Neisseria meningitidis in brain endothelial cells.

Invasion of brain endothelial cells (BECs) is central to the pathogenicity of Neisseria meningitidis infection. Here, we established a key role for the bioactive sphingolipid sphingosine-1-phosphate (S1P) and S1P receptor (S1PR) 2 in the uptake process. Quantitative sphingolipidome analyses of BECs infected with N. meningitidis revealed elevated S1P levels, which could be attributed to enhanced expression of the enzyme sphingosine kinase 1 and its activity. Increased activity was dependent on the interaction of meningococcal type IV pilus with the endothelial receptor CD147. Concurrently, infection led to increased expression of the S1PR2. Blocking S1PR2 signaling impaired epidermal growth factor receptor (EGFR) phosphorylation, which has been shown to be involved in cytoskeletal remodeling and bacterial endocytosis. Strikingly, targeting S1PR1 or S1PR3 also interfered with bacterial uptake. Collectively, our data support a critical role of the SphK/S1P/S1PR axis in the invasion of N. meningitidis into BECs, defining a potential target for adjuvant therapy

Cost-Utility Analysis of Transarterial Radioembolization With Yttrium-90 Resin Microspheres Compared With Sorafenib in Locally Advanced and Inoperable Hepatocellular Carcinoma

International audiencePurpose: The SARAH (Sorafenib Versus Radioembolization in Advanced Hepatocellular Carcinoma) trial (ClinicalTrials.gov Identifier NCT01482442) did not show a significant survival benefit for patients treated with transarterial radioembolization (TARE) compared with continuous oral sorafenib. The improved toxicity profile of patients treated with TARE in the trial, however, could result in a quality of life benefit in economic evaluations. Our objective was to perform a cost-utility analysis of TARE versus sorafenib for locally advanced and inoperable hepatocellular carcinoma.Methods: This study used patient-level data of the SARAH trial regarding resource use, progression-free and overall survival, and quality of life for the within-trial period for the patients who received at least 1 dose of sorafenib or 1 treatment with TARE according to their randomization arm. Data were extrapolated by using a partitioned survival model that incorporated costs and health outcomes, measured in life-years and quality-adjusted life-years (QALYs).Findings: The use of TARE resulted in an average loss of 0.036 life-year and a gain of 0.006 QALY compared with sorafenib. The aerage cost for the TARE arm was €17,179 (95% CI, 9,926-24,280) higher than the sorafenib arm, for an incremental cost-effectiveness ratio of €3,153,086/QALY. The probabilistic sensitivity analysis revealed a 50% risk that the TARE strategy was dominated. TARE was consistently dominated by sorafenib or had an incremental cost-effectiveness ratio more than €450,000/QALY in all sensitivity analyses.Implications: This economic evaluation of SARAH found that using radioembolization with yttrium-90 microspheres for the treatment of hepatocellular carcinoma was not a cost-effective option at the usually accepted willingness-to-pay thresholds

Health-related quality of life in locally advanced hepatocellular carcinoma treated by either radioembolisation or sorafenib (SARAH trial)

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