The regulation of the human liver-specific cytochrome P450 4F3B (CYP4F3B) isoform, a splice variant of the CYP4F3 gene with strong substrate specificity for long chain fatty acids, is yet an unsolved question. This report provides the first evidence that CYP4F3B is uniquely induced by prostaglandin A1 (PGA1) in human hepatocyte-like HepaRG cells and leads to the synthesis of 20-hydroxy-eicosatetraenoic acids (HETEs). Real time PCR, immunoblot analysis with a specific antipeptide antibody, and determination of fatty acid omega-hydroxylase activity demonstrate that PGA1 treatment strongly increases expression of CYP4F3B. This induction drives the production of 20-HETE (19-fold increase). SiRNA-mediated-silencing of CYP4F3 suppresses both 20-HETE synthesis and PGA1 induced 20-HETE production. Taken together, these results provide evidence that CYP4F3B is the key enzyme to produce 20-HETE by omega-hydroxylation of arachidonic acid in liver cells. Since 20-HETE is a potent activator of PPARalpha and an important inflammatory mediator, CYP4F3B may exert important functions in lipid homeostasis and in inflammatory diseases.
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http://dx.doi.org/10.1194/jlr.M800043-JLR200 | DOI Listing |
Cancer Res
January 2025
The ATIP-Avenir Inserm and ERC StG (Epi)genetic Vulnerabilities in Solid Tumors and Sarcoma Laboratory, Inserm Unit UMR 981, Université Paris-Saclay, Gustave Roussy, Villejuif, France.
Sci Rep
September 2024
INSERM U 1236, University of Rennes 1, Etablissement Français du Sang, 35000, Rennes, France.
T-cell-based adoptive immunotherapy is a new pillar of cancer care. Tumor-redirected B cells could also contribute to therapy if their manipulation to rewire immunoglobulin (Ig) genes is mastered. We designed a single-chain Ig-encoding cassette ("scFull-Ig") that redirects antigen specificity when inserted at a single position of the IgH locus.
View Article and Find Full Text PDFNat Commun
July 2024
Lyon University, Université Claude Bernard Lyon 1, Centre Léon Bérard, 69008, Lyon, France.
PD-1/PD-L1 blockade has so far shown limited survival benefit for high-grade ovarian carcinomas. By using paired samples from the NeoPembrOv randomized phase II trial (NCT03275506), for which primary outcomes are published, and by combining RNA-seq and multiplexed immunofluorescence staining, we explore the impact of NeoAdjuvant ChemoTherapy (NACT) ± Pembrolizumab (P) on the tumor environment, and identify parameters that correlated with response to immunotherapy as a pre-planned exploratory analysis. Indeed, i) combination therapy results in a significant increase in intraepithelial CD8PD-1 T cells, ii) combining endothelial and monocyte gene signatures with the CD8B/FOXP3 expression ratio is predictive of response to NACT + P with an area under the curve of 0.
View Article and Find Full Text PDFNat Cell Biol
July 2024
Institut Curie, PSL Research University, CNRS, UMR144, 26 rue d'Ulm, 75248, Paris Cedex 05, France.
Extracellular vesicles such as exosomes are now recognized as key players in intercellular communication. Their role is influenced by the specific repertoires of proteins and lipids, which are enriched when they are generated as intraluminal vesicles (ILVs) in multivesicular endosomes. Here we report that a key component of small extracellular vesicles, the tetraspanin CD63, sorts cholesterol to ILVs, generating a pool that can be mobilized by the NPC1/2 complex, and exported via exosomes to recipient cells.
View Article and Find Full Text PDFRMD Open
March 2024
Department of Rheumatology, Centro Hospitalar e Universitario de Coimbra EPE, Coimbra, Portugal
Objective: To assess which definition of remission best predicts good radiographic outcome (GRO) and good functional outcome (GFO) in rheumatoid arthritis, focusing the updated American College of Rheumatology/European Alliance of Associations for Rheumatology criteria.
Material And Methods: Meta-analyses of individual patient data (IPD) from randomised controlled trials (RCTs). Six definitions of remission were considered: (1) Boolean with Patient Global Assessment (PGA)≤1 (Boolean); (2) Simplified Disease Activity Index (SDAI)≤3.
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