Background: Oncogenic PIK3CA mutations (PIK3CA ) frequently occur in a higher proportion in luminal breast cancer (LBC), especially in refractory advanced cases, and are associated with changes in tumour cellular metabolism. Nevertheless, its effect on the progression of the immune microenvironment (TIME) within tumours and vital molecular events remains veiled.
Methods: Multiplex immunohistochemistry (mIHC) and single-cell mass cytometry (CyTOF) was used to describe the landscape of TIME in PIK3CA LBC. The PIK3CA mutant cell lines were established using CRISPER/Cas9 system. The gene expression levels, protein secretion and activity of signaling pathways were measured by real-time RT-PCR, ELISA, immunofluorescence staining or western blotting. GSEA analysis, transwell chemotaxis assay, live cell imaging, flow cytometry metabolite analysis targeting arachidonic acid, Dual-luciferase reporter assay, and Chromatin immunoprecipitation assay were used to investigate the underlying function and mechanism of the PI3K/5-LOX/LTB4 axis.
Results: PIK3CA LBC cells can induce an immunosuppressive TIME by recruiting myeloid-derived suppressor cells (MDSCs) and excluding cytotoxic T cells via the arachidonic acid (AA) metabolism pathway. Mechanistically, PIK3CA activates the transcription of 5-lipoxygenase (5-LOX) in a STAT3-dependent manner, which in turn directly results in high LTB4 production, binding to BLT2 on MDSCs and promoting their infiltration. Since a suppressive TIME is a critical barrier for the success of cancer immunotherapy, the strategies that can convert "cold" tumours into "hot" tumours were compared. Targeted therapy against the PI3K/5-LOX/LTB4 axis synergizing with immune checkpoint blockade (ICB) therapy achieved dramatic shrinkage in vivo.
Conclusions: The results emphasize that PIK3CA can induce immune evasion by recruiting MDSCs through the 5-LOX-dependent AA pathway, and combination targeted therapy with ICB may provide a promising treatment option for refractory advanced LBC patients.
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http://dx.doi.org/10.1002/ctm2.1483 | DOI Listing |
Nat Commun
January 2025
Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany.
Multimodal imaging by matrix-assisted laser desorption ionisation mass spectrometry imaging (MALDI MSI) and microscopy holds potential for understanding pathological mechanisms by mapping molecular signatures from the tissue microenvironment to specific cell populations. However, existing software solutions for MALDI MSI data analysis are incomplete, require programming skills and contain laborious manual steps, hindering broadly applicable, reproducible, and high-throughput analysis to generate impactful biological discoveries. Here, we present msiFlow, an accessible open-source, platform-independent and vendor-neutral software for end-to-end, high-throughput, transparent and reproducible analysis of multimodal imaging data.
View Article and Find Full Text PDFPostgrad Med J
January 2025
Shandong University of Traditional Chinese Medicine Affiliated Hospital, No. 42 Wenhua West Road, Lixia District, Jinan, Shandong Province 250011, China.
Background: The formation of gallstones is a multifactorial process involving lifestyle habits, lipid metabolism disorders, and genetic factors. This study aims to explore the association between 19 types of dietary fatty acids and gallstone disease using large-scale population data, assess the correlation between dietary fatty acids and serum fatty acids, and investigate the causal relationship between plasma lipids and gallstone disease from a genetic perspective.
Methods: We employed a cross-sectional study design, combined with logistic regression analysis to evaluate the association between dietary fatty acids and gallstone disease.
Nutrients
January 2025
State Key Laboratory Incubation Base for Green Processing of Chemical Engineering, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, China.
Objectives: Polysaccharides from are known to have several bioactive effects. Previous studies have found that low-molecular-weight polysaccharide (GP1) is degraded by and promotes the production of beneficial bacteria and metabolites, which improves immune disorder and intestinal injury, and then enhances the body's immune regulation ability. However, the immune regulation effect of GP1 on a healthy body has not been studied.
View Article and Find Full Text PDFPharmaceuticals (Basel)
January 2025
Health Sciences Postgraduate Program, São Francisco University-USF, Bragança Paulista 12916-900, SP, Brazil.
Background/objectives: This study investigates the metabolic profile of a single dose of etodolac in healthy volunteers, focusing on pharmacokinetics, clinical parameters, and metabolomic variations to identify biomarkers and pathways linked to drug response, efficacy, and safety.
Methods: Thirty-seven healthy volunteers, enrolled after rigorous health assessments, received a single dose of etodolac (Flancox 500 mg). Pharmacokinetic profiles were determined using tandem mass spectrometry analysis, and the metabolomic profiling was conducted using baseline samples (pre-dose) and samples at maximum drug concentration (post-dose) via liquid chromatography coupled with a quadrupole time-of-flight mass spectrometer.
Int J Mol Sci
January 2025
Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China.
Cadmium (Cd) pollution poses an important problem, but limited information is available about the toxicology effects of Cd on freshwater invertebrates. We investigated the accumulation, oxidative stress, microbial community changes, and transcriptomic alterations in apple snails ) under Cd stress. The snails were exposed to the 10 μg/L Cd solution for 16 days, followed by a 16-day elimination period.
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