Multi-omics approach reveals the impact of prognosis model-related genes on the tumor microenvironment in medulloblastomaHan, Chen, Jin
et alFront Oncol (2025) 15, 1477617
Abstract: The tumor microenvironment (TME) significantly impacts the progression and prognosis of medulloblastoma (MB). This study aimed to develop a TME-associated risk score(TMErisk) model using RNA sequencing data to predict patient outcomes and elucidate biological mechanisms.RNA sequencing data from 322 Tiantan and 763 GSE85217 MB samples were analyzed. Key gene modules related to immune and stromal components were identified using Weighted Gene Co-expression Network Analysis (WGCNA). Significant genes were screened using LASSO-COX and COX regression models. Single-cell RNA sequencing (scRNA-seq), single-cell ATAC sequencing (scATAC-seq), and spatial RNA analyses validated the findings.Differential expression analysis identified 731 upregulated and 15 downregulated genes in high vs. low immune score MB patients, and 686 upregulated and 43 downregulated genes in high vs. low stromal score patients. Eight key genes (CEBPB, OLFML2B, GGTA1, GZMA, TCIM, OLFML3, NAT1, and CD1C) were included in the TMErisk model, which demonstrated strong prognostic power. High TMErisk scores correlated with poorer survival, distinct immune cell infiltration patterns, and lower tumor cell stemness. Single-cell analyses revealed the expression dynamics of TMErisk genes across cell types, including macrophages, T cells, and NK cells, and identified key regulatory transcription factors. Spatial transcriptomics showed significant clustering of TMErisk genes in tumor regions, highlighting spatial heterogeneity and the formation of immune hubs.The TMErisk model enhances our understanding of the MB tumor microenvironment, serving as a robust prognostic tool and suggesting new avenues for targeted therapy.Copyright © 2025 Han, Chen, Jin, Li, Wang and Wang.
OLFML3 Promotes IRG1 Mitochondrial Localization and Modulates Mitochondrial Function in MacrophagesYu, Mei, Gu
et alInt J Biol Sci (2025) 21 (5), 2275-2295
Abstract: Olfactomedin-like protein 3 (OLFML3), belonging to olfactomedin (OLF) protein family, has poorly defined functions. Recent studies have reported the functions of OLFML3 in anti-viral immunity and tumorigenesis. In this study, we investigated the roles of OLFML3 in macrophages. In LPS- or Pseudomonas aeruginosa-induced acute lung injury (ALI) mouse model, OLFML3 depletion exacerbated inflammatory response, leading to reduced survival. OLFML3 achieved the in vivo activity by regulating macrophage phagocytosis and migration. Mass spectrometry analysis revealed immunoresponsive gene 1 (IRG1) as an OLFML3-interacting protein. IRG1 is a mitochondrial decarboxylase that catalyzes the conversion of cis-aconitate to itaconate, a myeloid-borne mitochondrial metabolite with immunomodulatory activities. Further investigation showed that OLFML3 could prevent LPS-induced mitochondrial dysfunction in macrophages by maintaining the homeostasis of mitochondrial membrane potential (MMP), mitochondrial reactive oxygen species (mtROS) and itaconate-related metabolites. In-depth protein-protein interaction studies showed that OLFML3 could promote IRG1 mitochondrial localization via a mitochondrial transport protein, apoptosis inducing factor mitochondria associated 1 (AIFM1). In summary, our study showed that OLFML3 could facilitate IRG1 mitochondrial localization and prevent LPS-induced mitochondrial dysfunction in macrophages.© The author(s).
Glymphatic system clearance and Alzheimer's disease risk: a CSF proteome-wide studyCullell, Caruana, Elias-Mas
et alAlzheimers Res Ther (2025) 17 (1), 31
Abstract: The emerging evidence of the role of the glymphatic system (GS) in Alzheimer's disease (AD) provides new opportunities for intervention from the earliest stages of the disease. The aim of the study is to evaluate the efficacy of GS in AD to identify new disease biomarkers.We performed a two-stage proteomic study to evaluate the GS health using intravenous gadolinium-based contrast agent (GBCA) with serial T1 3T magnetic resonance imaging (MRI) in individuals with amnestic mild cognitive impairment (aMCI). In Stage 1 (evaluated in the Cohort 1 of aMCI participants (n = 11)), we correlated the levels of 7K cerebrospinal fluid (CSF) proteins (estimated by SOMAscan) with GS health in 78 Freesurfer-segmented brain regions of interest (ROIs).A total of seven different proteins were significantly associated with GS health (p-value < 6.4 × 10-4). The stronger correlations were identified for NSUN6, GRAAK, OLFML3, ACTN2, RUXF, SHPS1 and TIM-4. A pathway enrichment analysis revealed that the proteins associated with GS health were mainly implicated in neurodegenerative processes, immunity and inflammation. In Stage 2, we validated these proteomic results in a new cohort of aMCI participants (with and without evidence of AD pathology in CSF (aMCI(-) and aMCI/AD( +); n = 22 and 7, respectively) and healthy controls (n = 10). Proteomic prediction models were generated in each ROI. These were compared with demographic-only models for identifying participants with aMCI(-) and aMCI/AD( +) vs controls. This analysis was repeated to determine if the models could identify those with aMCI/AD( +) from both aMCI(-) and controls. The proteomic models were found to outperform the demographic-only models.Our study identifies proteins linked with GS health and involved the immune system in aMCI participants.© 2025. The Author(s).
Heparin-enriched plasma proteome is significantly altered in Alzheimer's diseaseGuo, Ping, Dammer
et alMol Neurodegener (2024) 19 (1), 67
Abstract: Heparin binding proteins (HBPs) with roles in extracellular matrix assembly are strongly correlated to β-amyloid (Aβ) and tau pathology in Alzheimer's disease (AD) brain and cerebrospinal fluid (CSF). However, it remains challenging to detect these proteins in plasma using standard mass spectrometry-based proteomic approaches.We employed heparin-affinity chromatography, followed by off-line fractionation and tandem mass tag mass spectrometry (TMT-MS), to enrich HBPs from plasma obtained from AD (n = 62) and control (n = 47) samples. These profiles were then correlated to Aβ, tau and phosphorylated tau (pTau) CSF biomarkers and plasma pTau181 from the same individuals, as well as a consensus brain proteome network to assess the overlap with AD brain pathophysiology.Heparin enrichment from plasma was highly reproducible, enriched well-known HBPs like APOE and thrombin, and depleted high-abundant proteins such as albumin. A total of 2865 proteins, spanning 10 orders of magnitude in abundance, were measured across 109 samples. Compared to the consensus AD brain protein co-expression network, we observed that specific plasma proteins exhibited consistent direction of change in both brain and plasma, whereas others displayed divergent changes, highlighting the complex interplay between the two compartments. Elevated proteins in AD plasma, when compared to controls, included members of the matrisome module in brain that accumulate with Aβ deposits, such as SMOC1, SMOC2, SPON1, MDK, OLFML3, FRZB, GPNMB, and the APOE4 proteoform. Additionally, heparin-enriched proteins in plasma demonstrated significant correlations with conventional AD CSF biomarkers, including Aβ, total tau, pTau, and plasma pTau181. A panel of five plasma proteins classified AD from control individuals with an area under the curve (AUC) of 0.85. When combined with plasma pTau181, the panel significantly improved the classification performance of pTau181 alone, increasing the AUC from 0.93 to 0.98. This suggests that the heparin-enriched plasma proteome captures additional variance in cognitive dementia beyond what is explained by pTau181.These findings support the utility of a heparin-affinity approach coupled with TMT-MS for enriching amyloid-associated proteins, as well as a wide spectrum of plasma biomarkers that reflect pathological changes in the AD brain.© 2024. The Author(s).
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