Background: Septic cardiomyopathy is a frequent complication in patients with sepsis and is associated with a high mortality rate. Given its clinical significance, understanding the precise underlying mechanism is of great value.

Methods and results: Our results unveiled that Z-DNA binding protein 1 (ZBP1) is upregulated in myocardial tissues of lipopolysaccharide (LPS)-treated mice. Single-cell mRNA sequencing (scRNA-seq) and single-nucleus mRNA sequencing (snRNA-seq) indicated that Zbp1 mRNA in endothelial cells, fibroblasts and macrophages appeared to be elevated by LPS, which is partially consistent with the results of immunofluorescence. Through echocardiography, we identified that global deletion of ZBP1 improves cardiac dysfunction and the survival rate of LPS-treated mice. Mechanistically, snRNA-seq showed that ZBP1 is mainly expressed in macrophages and deletion of ZBP1 promotes the macrophage polarisation towards M2-subtype, which reduces inflammatory cell infiltration. Notably, myeloid-specific deficiency of ZBP1 also promotes M2 macrophage polarisation and improves cardiac dysfunction, validating the role of macrophage-derived ZBP1 in septic myocardial dysfunction. Finally, we revealed that LPS increases the transcription and expression of ZBP1 through signal transducer and activator of transcription 1 (STAT1). Fludarabine, the inhibitor of STAT1, could also promote M2 macrophage polarisation and improve cardiac dysfunction of LPS-treated mice.

Conclusions: Our study provides evidence of a novel STAT1-ZBP1 axis in macrophage promoting septic cardiomyopathy, and underscores the potential of macrophage-derived ZBP1 as a therapeutic target for septic cardiomyopathy.

Obesity and allergic diseases are global health concerns, both of which are seeing an increase in prevalence in recent years. Obesity has been recognised as an important comorbidity in subpopulations with allergic airway diseases, which represents a unique phenotype and endotype. Obesity-related allergic airway diseases are associated with exacerbated clinical symptom burden, altered immune response, increased disease severity and compromised predictive capability of conventional biomarkers for evaluating endotype and prognosis. Moreover, treatment of obesity-related allergic airway diseases is challenging because this unique endotype and phenotype is associated with poor response to standard therapeutic strategies. Therapeutic regimen that involves weight loss by non-surgical and surgical interventions, gut microbiome-targeted treatment, glucagon-like peptide-1 receptor agonist and other agents should be considered in this population. In this review, we outline the current knowledge of the impact of obesity on prevalence, endotypes, clinical symptom and management of allergic airway diseases. Increased understanding of the implications of obesity may contribute to better treatment options for the obesity-related refractory airway inflammation, particularly in precision medicine.

Ischemic cardiomyopathy (ICM) is characterised by the insufficient capacity of the heart to effectively pump blood, which ultimately contributes to heart failure (HF). In this study, the down regulation of SENP1 is identified in the cardiomyocyte of ICM mouse models and in patients. The depletion of SENP1 exacerbates hypoxia-induced apoptosis of cardiomyocytes in vitro and deteriorated cardiomyocyte injury of ICM mice in vivo. Mechanistically, SENP1 deSUMOylates the SUMO2-mediated modification of MEF2C at lysine 401 for stabilising protein stability. Moreover, the interaction with SENP1 controls the nuclear condensation of MEF2C to promote the expression of genes critical for cardiomyocyte function. When rescuing SENP1 expression using adeno-associated virus serotype 9, the attenuation of cardiomyocyte injury is discerned in the mouse model of ICM. Therefore, these finding elicits a previously unrecognised role and mechanism of SENP1 in safeguarding cardiomyocyte in ICM progression while establishing a basis for the development of SENP1 as a potential marker for ICM diagnosis and treatment.

Background: Gastric cancer (GC) exhibits high heterogeneity that relies on the oncogenic properties of cancer cells and multicellular interactions in the tumour microenvironment. However, the heterogeneity of GC and their molecular characteristics are still largely unexplored.

Methods: We employed single-cell and spatial transcriptomics to comprehensively map the intra-tumoural heterogeneity within GC. Additionally, in vitro experiments, clinical sample analyses, and patient-derived organoid models (PDOs) were conducted to validate the key interaction patterns between tumor cells and stromal cells.

Results: Seven robust meta-programs (MP1–MP7) in GC were defined with distinct biological significance and spatial distributions. MP3 and MP4 were intimately associated with distinct CD8 T cells skewed toward a cytotoxic or exhaustion state, while MP7, characterised by the highest degree of malignancy, harboured an immune lockdown microenvironment around it and spatially associated with myofibroblasts (myCAFs). Notably, we clarified the interplay between the MP7 and myCAFs, where MP7 induces the chemotactic migration of fibroblasts and promoting their transformation into myCAFs via GDF15/TGFBR2, and in turn, myCAFs-derived RSPO3 up-regulates EGR1 to promote the transformation to MP7 in GC cells and human PDOs. Ultimately, the accumulation of myCAFs around MP7 led to fewer infiltration of CD8 T cells, resulting an immune-deprived microenvironment and the diminished efficacy of immunotherapy. Additionally, based on the gene expression signatures of MP7 GC cells, we predicted specific drugs and verified more potent inhibitory effects of Taselisib and Lapatinib for MP7 GC cells than conventional drugs at the same concentration.

Conclusion: Taken together, these results deepened the understanding of GC heterogeneity and paved the way for novel therapeutic strategies by targeting MP7 GC cells and their interaction loop with myCAFs in GC treatment.

Mitochondria-derived vesicles (MDVs) participate in early cellular defence mechanisms initiated in response to mitochondrial damage. They maintain mitochondrial quality control (MQC) by clearing damaged mitochondrial components, thereby ensuring the normal functioning of cellular processes. This process is crucial for cell survival and health, as mitochondria are the energy factories of cells, and their damage can cause cellular dysfunction and even death. Recent studies have shown that MDVs not only maintain mitochondrial health but also have a significant impact on tumour progression. MDVs selectively encapsulate and transport damaged mitochondrial proteins under oxidative stress and reduce the adverse effects of mitochondrial damage on cells, which may promote the survival and proliferation of tumour cells. Furthermore, it has been indicated that after cells experience mild stress, the number of MDVs significantly increases within 2–6 h, whereas mitophagy, a process of clearing damaged mitochondria, occurs 12–24 h later. This suggests that MDVs play a critical role in the early stress response of cells. Moreover, MDVs also have a significant role in intercellular communication, specifically in the tumour microenvironment. They can carry and transmit various bioactive molecules, such as proteins, nucleic acids, and lipids, which regulate tumour cell's growth, invasion, and metastasis. This intercellular communication may facilitate tumour spread and metastasis, making MDVs a potential therapeutic target. Advances in MDV research have identified novel biomarkers, clarified regulatory mechanisms, and provided evidence for clinical use. These breakthroughs pave the way for novel MDV-targeted therapies, offering improved treatment alternatives for cancer patients. Further research can identify MDVs' role in tumour development and elucidate future cancer treatment horizons.

Background: Intervertebral disc degeneration (IDD), a chronic and multifactorial skeletal disorder, is the primary cause of low back pain. It results in reduced disc height and nucleus pulposus hydration due to proteoglycan loss and nucleus pulposus cells (NPCs) dysfunction within a hypoxic microenvironment. Metabolic dysregulation initiates catabolic processes, leading to extracellular matrix (ECM) degradation and compromising disc biomechanical integrity. Emerging evidence highlights epigenetic modifications as pivotal in IDD, influencing NPC gene expression transcriptionally and post-transcriptionally.

Methods: In order to understand the epigenetic underpinnings of IDD, our study provided a comprehensive profile of chromatin accessibility changes in degenerated NPCs using Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq).

Results: With motif enrichment analysis, we identified the activator protein-1 (AP-1) transcription factor critical in driving the chromatin accessibility changes during IDD. Integrative ATAC-seq and transcriptional profiling revealed cell migration-inducing protein (CEMIP) as a key biomarker and contributor to IDD, exhibiting marked upregulation in IDD. Furthermore, we demonstrated that the AP-1 family, especially, c-Fos, orchestrates the upregulation of CEMIP. Elevated CEMIP plasma levels correlated with clinical IDD severity, and CEMIP knockout mice demonstrated improved IDD.

Conclusions: Mechanistically, CEMIP disrupted ECM homeostasis through its regulation of high molecular weight hyaluronic acid (HMW-HA) degradation, and its contribution to fibrotic changes. Our findings highlight CEMIP's vital role in IDD and identify the AP-1 family as a critical regulator of IDD, providing new potential therapeutic targets for novel IDD interventions.

Background: Our previous findings have underscored the role of innate immunity in obliterative bronchiolitis (OB). However, despite the central importance of the cyclic GMP‒AMP synthase (cGAS)/stimulator of interferon genes (STING) signalling pathway in innate immune responses, its specific contribution to OB progression remains largely unexplored.

Methods: A murine orthotopic tracheal transplantation model was established to replicate OB pathogenesis. RNA sequencing and single-cell RNA sequencing data were analysed to investigate mechanisms underlying OB. Key molecules of the cGAS/STING pathway were assessed using immunofluorescence staining. Macrophage-specific Sting1 knockout mice were generated to investigate the role of the cGAS/STING pathway in OB. Haematoxylin and eosin staining and Masson's trichrome staining were utilised to evaluate allograft stenosis and fibrosis. Immune cell infiltration and cytokine expression were analysed using immunofluorescence staining and qRT-PCR. Flow cytometry was used to characterise splenic T-cell subsets and assess co-stimulatory molecule expression in macrophages.

Results: The cGAS/STING pathway was upregulated in macrophages infiltrating allografts. Macrophage-specific Sting1 knockout significantly attenuated alloreactive T-cell responses and alleviated OB. Furthermore, Sting1 deletion reduced the expression of inflammatory marker NOS2, antigen-presenting molecule MHC class II and co-stimulatory molecules (CD80 and CD86) in macrophages. Mechanistically, Sting1 knockout inhibited the production of interferon-α2 (IFN-α2), while the protective effect of macrophage-specific Sting knockout was reversed by IFN-α2 administration. Importantly, STING inhibition enhanced the allograft tolerance-promoting effects of cytotoxic T-lymphocyte-associated antigen 4-Ig (CTLA4-Ig), leading to the preservation of the airway epithelium.

Conclusions: Our study demonstrated that cGAS/STING signalling pathway exacerbated allograft rejection in an IFN-α2-dependent manner. These findings provide insights into potential novel strategies for prolonging allograft survival.

Background: Hepatocellular carcinoma remains one of the most lethal cancers, characterized by poor prognosis and low life expectancy. Unfortunately, there are very few molecular therapeutic options available for it. Sorafenib is a current standard first-line treatment for advanced hepatocellular carcinoma, however, drug resistance significantly limits its therapeutic efficacy.

Methods: Ubiquitin-specific protease 22 (USP22) expression level and its prognostic significance in hepatocellular carcinoma were analyzed using The Cancer Genome Atlas (TCGA) database. A series of cellular experiments related to cell proliferation and ferroptosis, and mouse tumor-bearing experiments were performed to investigate the role of USP22 in hepatocellular carcinoma cell growth and Sorafenib resistance. Flag affinity purification coupled with mass spectrometry, co-immunoprecipitation, and ubiquitination assays were conducted to identify direct substrates of USP22. Spike-in chromatin-immunoprecipitation (ChIP)-seq, RNA-seq, and ChIP assays were employed to explore the transcriptional substrates of USP22 as an H2BK120ub deubiquitinase.

Results: Analysis of TCGA database reveals that USP22 is highly expressed in hepatocellular carcinoma tissues, which is closely associated with poor patient prognosis. Our data further indicates that USP22 promotes the proliferation of hepatocellular carcinoma cells via deubiquitinating and stabilizing cyclin-dependent kinase 11B (CDK11B). Additionally, USP22 acts as a novel inducer of Sorafenib resistance and suppresses Sorafenib-triggered ferroptosis in hepatocellular carcinoma cells. It reduces the transcription of transferrin receptor (TFRC) by decreasing H2BK120ub occupancy at TFRC transcription start site (TSS) downstream region, thereby inhibiting ferroptosis upon Sorafenib treatment. Finally, animal experiments confirm the role of USP22 in promoting hepatocellular carcinoma cell growth and Sorafenib resistance in vivo. Taken together, this study demonstrates that USP22 promotes hepatocellular carcinoma growth and inhibits Sorafenib-induced ferroptosis by deubiquitinating non-histone substrate CDK11B and histone H2B, respectively.

Conclusions: Our findings suggest USP22 as a promising prognostic biomarker and therapeutic target for hepatocellular carcinoma patients, particularly those with Sorafenib resistance.

Background: Engineered extracellular vesicles (EVs) are emerging as a highly potential platform for targeted drug delivery in cancer therapy. Although intravenous injection is commonly used in EV treatment, there is growing interest in using microneedles (MNs) for transdermal EV delivery; however, comprehensive studies comparing the tissue distribution, safety and antitumour efficacy of these two approaches for delivering engineered EVs remain scarce.

Methods: We used EVs derived from umbilical cord mesenchymal stem cells, modified with phospholipid‒polyethylene glycol‒N-hydroxysuccinimide and conjugated with CD38 peptides (CD38-EVs), to target myeloma cells that highly express CD38 antigen, and tested their safety and antitumour efficacy in mice with subcutaneous plasmacytoma, administrated via dissolvable transdermal MNs or intravenous injection. Flow cytometry, immunofluorescence and fluorescence molecular projection imaging analysis were employed to evaluate the distribution of CD38-EVs at the cellular level and within living systems. Additionally, histopathological analysis and biochemical analyses were conducted to assess the antitumour effects and safety of CD38-EVs loaded with doxorubicin (CD38-EVs-Dox).

Results: Compared to standard EVs, CD38-EVs exhibited enhanced uptake by CD38^high tumour cells and reduced uptake by CD38-negative non-tumour cells in vitro. In plasmacytoma NOD/SCID mouse models, CD38-EVs encapsulated within MNs (CD38-EVs^MNs) effectively targeted the tumour cells much more than the standard EVs encapsulated within MNs (EVs^MNs) and CD38-EVs intravenously administrated (CD38-EVs^i.v), with reduced distribution to the lungs and spleen. Additionally, CD38-EVs-Dox induced significantly greater cytotoxicity against the tumour cells than EVs-Dox in vitro, and CD38-EVs-Dox^MNs significantly reduced tumour burden compared to both EVs-Dox^MNs and CD38-EVs-Dox^i.v, while maintaining favourable safety profiles.

Conclusions: CD38-EVs-Dox^MNs have superior efficacy and safety in treating plasmacytoma mice, compared to CD38-EVs-Dox^i.v, providing novel insights into the potential of MNs as a platform for delivering targeted engineered EVs in tumour therapy.

Background: The multidimensional regulatory mechanism of the gut–brain–immune axis in the context of inflammatory bowel disease (IBD) has garnered significant attention, particularly regarding how intestinal microbiota finely regulates immune responses through immune cells and sensory neurons.

Main Body: Metabolites produced by intestinal microbiota influence the phenotype switching of immune cells via complex signalling pathways, thereby modulating their anti-inflammatory and pro-inflammatory functions during intestinal inflammation. Furthermore, sensory neurons exhibit heightened sensitivity to microbial-derived signals, which is essential for preserving intestinal balance and controlling pathological inflammation by integrating peripheral environmental signals with local immune responses. The dynamic equilibrium between immune cells and the neuroimmunoregulation mediated by sensory neurons collectively sustains immune homeostasis within the intestine. However, this coordination mechanism is markedly disrupted under the pathological conditions associated with IBD.

Conclusion: An in-depth exploration of the interactions among immune cells, gut microbiota and sensory neurons may yield significant insights into the pathological mechanisms underlying IBD and guide the creation of new treatment approaches.

Analysing the genome, epigenome, transcriptome, proteome, and metabolome within the spatial context of cells has transformed our understanding of tumour spatiotemporal heterogeneity. Advances in spatial multi-omics technologies now reveal complex molecular interactions shaping cellular behaviour and tissue dynamics. This review highlights key technologies and computational methods that have advanced spatial domain identification and their pseudo-relations, as well as inference of intra- and inter-cellular molecular networks that drive disease progression. We also discuss strategies to address major challenges, including data sparsity, high-dimensionality, scalability, and heterogeneity. Furthermore, we outline how spatial multi-omics enables novel insights into disease mechanisms, advancing precision medicine and informing targeted therapies.

Background: Immune checkpoint blockade, particularly targeting programmed death 1 (PD-1) and programmed death ligand 1 (PD-L1), shows promise in treating hepatocellular carcinoma (HCC). However, acquired resistance, especially in patients with ‘hot tumours’, limits sustained benefits. Lysine-specific demethylase 1 (LSD1) plays a role in converting ‘cold tumours’ to ‘hot tumours’, but its involvement in PD-1 inhibitor resistance in HCC is unclear.

Methods: LSD1 and PD-L1 expression, along with CD8⁺ T cell infiltration, were assessed using immunohistochemistry in HCC tissues, correlating these markers with patient prognosis. The impact of LSD1 deletion on tumour cell proliferation and CD8⁺ T cell interactions was examined in vitro. Mouse models were used to study the combined effects of LSD1 inhibition and anti-PD-1 therapy on tumour growth and the tumour microenvironment (TME). The clinical relevance of LSD1, CD74 and effector CD8⁺ T cells was validated in advanced HCC patients treated with PD-1 blockade.

Results: LSD1 overexpression in HCC patients correlated with reduced PD-L1 expression, less CD8⁺ T cell infiltration and poorer prognosis. LSD1 deletion increased PD-L1 expression, boosted effector CD8⁺ T cells in vitro and inhibited tumour growth in vivo. While anti-PD-1 monotherapy initially suppressed tumour growth, it led to relapse upon antibody withdrawal. In contrast, combining LSD1 inhibition with anti-PD-1 therapy effectively halted tumour growth and prevented relapse, likely through TME remodelling, enhanced CD8⁺ T cell activity and improved CD74-mediated antigen presentation. Clinically, low LSD1 expression was associated with better response to anti-PD-1 therapy.

Conclusion: LSD1 deletion reshapes the TME, enhances CD8⁺ T cell function and prevents acquired resistance to anti-PD-1 therapy in HCC. The combination of LSD1 inhibitors and PD-1 blockade offers a promising strategy for overcoming resistance in advanced HCC.

Background: Diffuse large B-cell lymphoma (DLBCL), an aggressive type of non-Hodgkin's lymphoma, has a high relapse/refractory rate. We previously identified sex-determining region Y (SRY)-box transcription factor (SOX9) as a transcription factor that serves as a prognostic biomarker, particularly in BCL2-overexpressing DLBCL, and plays a vital role in lymphomagenesis. However, the molecular mechanisms that modulate the aberrant expression of SOX9 in this DLBCL subset remain unknown.

Methods: Cell viability, apoptosis and cell cycle assays were performed to determine whether SOX9 contributes to DLBCL chemoresistance and rescues silencing IRF4-induced phenotypes. Protein‒protein interactions and protein ubiquitination were elucidated using immunoprecipitation, immunohistochemistry, immunofluorescence and immunoblotting. Chromatin immunoprecipitation sequencing (ChIP-seq), ChIP and dual-luciferase reporter assays were used to investigate IRF4 binding to the SOX9 promoter. The therapeutic potential of IRF4 inhibition was evaluated in vitro and in a mouse model of DLBCL xenografts.

Results: SOX9 enhanced the resistance of the BCL2-overexpressing DLBCL subset to chemotherapy or a BCL2 inhibitor. Moreover, BCL2 inhibition downregulated SOX9 in an immunoglobulin heavy chain/BCL2-positive DLBCL subset. We further identified IRF4 as a key regulator of BCL2-induced SOX9 expression, and ChIP-seq confirmed that IRF4 is a key transcription factor for SOX9 in DLBCL. In addition, BCL2 promotes IRF4 entry into the nucleus by enhancing protein stability and downregulating proteasomal ubiquitination, thereby enforcing SOX9-mediated phenotypes. Finally, in a DLBCL cell line and xenografted mouse model, in vivo inhibition of IRF4 with an hIRF4 antisense oligonucleotide repressed lymphomagenesis and DLBCL chemoresistance.

Conclusions: Our data support the conclusion that IRF4 plays an essential role in BCL2-induced upregulation of SOX9 expression, and targeting IRF4 may represent a promising therapeutic strategy to cure relapsed and refractory DLBCL.

Background: Mutations in c-MET receptor tyrosine kinase (MET) can be primary oncogenic drivers of multiple tumour types or can be acquired as mechanisms of resistance to therapy. MET tyrosine kinase inhibitors (TKIs) are classified as type I or type II inhibitors, with the former binding to the DFG-in, active conformation of MET, and the latter to the DFG-out, inactive conformation of MET. Understanding how the different classes of MET TKIs impact tumours with varied MET alterations is critical to optimising treatment for patients with MET altered cancers. Here, we characterise MET mutations identified in patients’ tumours and assess responsiveness to type I and II TKIs.

Methods: We used structural modelling, in vitro kinase and in cell-based assays to assess the response of MET mutations to type I and II TKIs. We then translated our pre-clinical findings and treated patients with MET mutant tumours with selected inhibitors.

Results: We detected the emergence of four (three previously uncharacterised and one known) MET resistance mutations (MET^G1090A, MET^D1213H, MET^R1227K and a MET^Y1230S) in samples from patients with multiple solid tumours, including patients who had been previously treated with type I inhibitors.In silico modelling and biochemical assays across a variety of MET alterations, including the uncharacterised MET^G1090A and the MET^Y1230S substitutions, demonstrated impaired binding of type I but not of type II TKIs (i.e., cabozantinib/foretinib). Applying our pre-clinical findings, we then treated two patients (one with a non-small-cell lung cancer and one with a renal cell carcinoma) whose tumours harboured these previously uncharacterised MET alterations with cabozantinib, a type II MET TKI, and observed clinical responses.

Conclusions: Comprehensive characterisation of the sensitivity of mutations to different TKI classes in oncogenic kinases may guide clinical intervention and overcome resistance to targeted therapies in selected cases.

Background and purpose: In this study, we applied an induced pluripotent stem cell (iPSC)-based model of inherited erythromelalgia (IEM) to screen a library of 281 small molecules, aiming to identify candidate pain-modulating compounds.

Experimental approach: Human iPSC-derived sensory neuron-like cells, which exhibit action potentials in response to noxious stimulation, were evaluated using whole-cell patch-clamp and microelectrode array (MEA) techniques.

Key results: Sensory neuron-like cells derived from individuals with IEM showed spontaneous electrical activity characteristic of genetic pain disorders. The drug screen identified four compounds (AZ106, AZ129, AZ037 and AZ237) that significantly decreased spontaneous firing with minimal toxicity. The calculated IC₅₀ values indicate the potential efficacy of these compounds. Electrophysiological analysis confirmed the compounds’ ability to reduce action potential generation in IEM patient-specific iPSC-derived sensory neuron-like cells.

Conclusions and implications: Our screening approach demonstrates the reproducibility and effectiveness of human neuronal disease modelling offering a promising avenue for discovering new analgesics. These findings address a critical gap in current therapeutic strategies for both general and neuropathic pain, warranting further investigation. This study highlights the innovative use of patient-derived iPSC sensory neuronal models in pain research and emphasises the potential for personalised medicine in developing targeted analgesics.

Background: V-set and immunoglobulin domain containing 4 (VSIG4) is a B7-family-related protein almost exclusively expressed on macrophages. The difference in its expression mediates the dynamic transformation of the polarization state of macrophages, but the underlying mechanism is still unclear. We sought to reveal the correlation between VSIG4 and the polarization of tumour-associated macrophages (TAMs) and the immune escape of tumour cells in colorectal cancer (CRC).

Methods: THP-1 monocyte-derived macrophages expressing different levels of VSIG4 were used for in vitro investigations. In addition, the co-culture system was used to verify the effect of tumour cells on the expression of VSIG4 in macrophages, and the effect of VSIG4 expression level on tumour cells in turn. Subcutaneous xenograft models evaluated the tumour growth inhibition efficacy of VSIG4 blockade as monotherapy and combined with immune checkpoint inhibitors (ICIs).

Results: CRC cells secreted lactate to promote VSIG4 expression in macrophages. On the contrary, VSIG4 promoted macrophage M2 polarization and induced malignant progression of tumour cells by promoting M2 macrophage secretion of heparin-bound epidermal growth factor. In vivo experiments confirmed that knockdown VSIG4 inhibited tumour growth and improved the efficacy of ICIs therapy. Mechanistically, lactate secreted by CRC cells promoted its expression by influencing the epigenetic modification of VSIG4 in macrophages. In addition, VSIG4 enhanced the fatty acid oxidation (FAO) of macrophages and upregulated PPAR-γ expression by activating the JAK2/STAT3 pathway, which ultimately induced M2 polarization of macrophages. Downregulation of VSIG4 or blocking of FAO reversed the M2 polarization process of macrophages.

Conclusions: Our findings provide a molecular basis for VSIG4 to influence TAMs polarization by regulating the reprogramming of FAO, suggesting that targeting VSIG4 in macrophages could enhance the ICIs efficacy and represent a new combination therapy strategy for immunotherapy of CRC.

Persistent stimulation from cancer antigens leads to T lymphocytes (T cells) exhaustion, with up-regulated expression of co-inhibitory receptors, including programmed death-1 (PD-1), cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), lymphocyte-activation gene 3 (LAG-3), T cell immunoglobulin and mucin domain 3 (TIM-3) and T cell immunoreceptor with Ig and ITIM domains (TIGIT). These receptors collectively impair T cell function via distinct molecular pathways, contributing to immune evasion and cancer progression. This review highlights the therapeutic promise of immune checkpoint inhibitors (ICIs) in reversing T cell exhaustion while delving into the complex molecular processes and functional works of these important co-inhibitory receptors in tumourigenesis. Additionally, we examine the synergistic effects of combining ICIs with other therapeutic strategies, which can enhance anti-tumour efficacy. Finally, the clinical implications of bispecific antibodies are highlighted, representing a promising frontier in cancer immunotherapy, that could revolutionise treatment paradigms while improving patient outcomes.

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating illness characterized by post-exertional malaise (PEM), a worsening of symptoms following exertion. The biological mechanisms underlying PEM remain unclear. Extracellular vesicles (EVs) play a key role in cell–cell communication and may provide insight into ME/CFS pathophysiology post-exertion. Emerging evidence suggests similarities between ME/CFS and Long COVID, including PEM and overlapping immune and metabolic dysfunctions, highlighting the need for deeper mechanistic understanding.

Methods: This study explores the EV proteome response to exercise in 10 males with ME/CFS and 12 well-matched sedentary male controls. Participants underwent a maximal cardiopulmonary exercise test, and plasma samples were collected at baseline, 15 min, and 24 h postexercise. EVs were isolated from plasma using size-exclusion chromatography and characterized with nanoparticle tracking analysis. EV protein abundance was quantified with untargeted proteomics (nanoLC-MS/MS). Comprehensive analyses included differential abundance, pathway enrichment, protein–protein interaction networks, and correlations between EV protein dynamics and clinical or exercise physiology data.

Results: ME/CFS patients exhibited many significantly altered EV proteomic responses compared with controls, including downregulation of TCA cycle-related proteins and upregulation of complement system proteins at 15 min postexercise. Changes in proteins involved in protein folding and the endoplasmic reticulum (ER) stress response during recovery were highly correlated with PEM severity, highlighting their potential as therapeutic targets. EV protein changes postexercise were also associated with disease severity and unrefreshing sleep. Correlations between EV protein levels and the exercise parameters VO₂ peak and ventilatory anaerobic threshold were observed in controls but were absent in ME/CFS patients, suggesting disrupted EV-mediated physiological processes.

Conclusions: ME/CFS patients exhibit a maladaptive EV proteomic response to exercise, characterized by metabolic impairments, immune overactivation, and ER stress response dysregulation. These findings provide insight into the molecular basis of PEM and suggest promising targets for improving recovery and energy metabolism in ME/CFS.

Ischaemic stroke is one of the most common serious diseases observed in elderly people, which is caused by ischaemia-reperfusion (I/R) injury. Ovarian tumour domain-containing protein 3 (OTUD3) is a member of the ovarian tumour proteases (OTUs) family of deubiquitination enzymes located in the cytoplasm. We previously showed that the expression of OTUD3 in neurons was significantly reduced after cerebral I/R in mice. In addition, OTUD3 knockdown aggravated ferroptosis and brain damage following I/R in mice, and overexpression of OTUD3 reduced the mortality of cortical neurons in an oxygen glucose deprivation model (OGD/R). Co-immunoprecipitation-mass spectrometry analysis revealed that OTUD3 could bind to the amino acid sequence 35–305 of PLK1. Single-cell sequencing results suggested that PLK1 expression was significantly reduced in mouse neurons after I/R injury. Similarly, reduced PLK1 expression was found in the cortical brain tissues of I/R mice and in the OGD/R-stimulated primary cortical neurons of mice. In vitro experiments showed that OTUD3 overexpression led to the upregulation of PLK1 expression, and inhibition of PLK1 suppressed the inhibitory effect of OTUD3 overexpression on ferroptosis. Moreover, PLK1 positively regulated the PI3K/AKT signalling pathway in neurons after I/R injury, and inhibition of PI3K activity suppressed the inhibitory effect of PLK1 on ferroptosis. Ubiquitination experiments showed that OTUD3 modified PLK1 through deubiquitinating K48-linked ubiquitination, thereby reducing its degradation by ubiquitination and stabilizing PLK1 expression. These results indicated that OTUD3 could upregulate PLK1 through deubiquitination modification, thereby activating the PI3K/AKT signalling pathway and reducing ferroptosis after cerebral I/R. Animal behavioural experiments and cellular methyl thiazolyl tetrazolium and lactate dehydrogenase experiments revealed that inhibition of PLK1 exacerbated brain damage after I/R in mice. Inhibition of OTUD3 deubiquitination enzyme activity attenuated the neuroprotective effect of OTUD3. In conclusion, our findings provide evidence that OTUD3 reduces ferroptosis by upregulating PLK1 expression through deubiquitination modification and exerts neuroprotective effects in cerebral I/R injury.

Background: Prolonged sedentary time is a strong risk factor for insulin resistance. Recent evidence indicates that gut microbiota may influence the regulation of insulin sensitivity and demonstrates a distinct profile between sedentary and physically active individuals. However, whether and how microbial metabolism mediates the progression of insulin resistance induced by prolonged sedentary time remains unclear.

Methods: 560 male participants without hypoglycaemic therapy were included, and insulin resistance was evaluated using the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). The gut microbiota was identified through metagenomics, host genetic data were obtained using a genotyping array, and plasma metabolites were quantified by liquid chromatography mass spectrometry.

Results: A panel of 15 sedentary-related species and 38 sedentary-associated metabolic capacities accounted for 31.68% and 21.48% of the sedentary time-related variation in HOMA-IR, respectively. Specifically, decreased Roseburia sp. CAG:471, Intestinibacter bartlettii, and Firmicutes bacterium CAG:83, but increased Bacteroides xylanisolvens related to longer sedentary time, were causally linked to the development of insulin resistance. Furthermore, integrative analysis with metabolomics identified reduced L-citrulline and L-serine, resulting from a suppression of arginine biosynthesis as key microbial effectors linking longer sedentary time to enhanced insulin resistance.

Conclusions: In summary, our findings provide insights into the mediating role of gut microbiota on the progression of insulin resistance induced by excessive sedentary time, and highlight the possibility of counteracting the detrimental effect of prolonged sedentary time on insulin resistance by microbiota-modifying interventions.

Background: Abdominal aortic aneurysm (AAA) is characterized by progressive dilation of the abdominal aorta that has a high prevalence of death due to aortic rupture. The hallmark of AAA is severe degeneration of the aortic media with the loss of vascular smooth muscle cells (VSMCs), the main source of extracellular matrix (ECM) proteins. CD248 was originally implicated in angiogenesis and tumourigenesis, but its role in the development of AAA remains unclear.

Methods: Mice lacking CD248 (Cd248^−/−) were generated and evaluated for angiotensin II (Ang II) and high-cholesterol diet feeding induced AAA. Loss-of-function approaches in A7r5 and C3H10T1/2 cells were used to study the involvement of CD248 in the Ang II signalling.

Results: CD248 expression was upregulated in the media and adventitia of patients and mice with aortic aneurysm. CD248 deficiency in mice exacerbates Ang II-induced aortic lesion along with severe disruption of elastic fibres and the VSMC layer. Interestingly, while compensatory ECM deposition was found in the aortic lesion of Cd248^−/− mice, collagen I content and p38 activation were significantly attenuated. Silencing of CD248 in VSMCs downregulated mitogen-activated protein kinase activation and ECM production. Loss of CD248 in VSMCs destabilized the membrane receptors for Ang II and platelet-derived growth factor (PDGF), and the C-terminal cytoplasmic domain of CD248 is apparently involved in this interaction.

Conclusions: The findings reveal that CD248 regulates the stability of the membrane receptors for Ang II and PDGF in VSMCs to transduce signals for collagen production in combating the loss of aortic wall strength during vascular remodelling.

Background: Despite rapid advances in HCC therapy, surgical resection is still the most effective treatment. However, postoperative relapse develops in a large population and the mechanism remains to be explored.

Methods: HCC resection samples were retrospectively collected from 12 nonrelapsed and 15 relapsed HCC patients for RNA sequencing. Liver-specific solute carrier family 39 member 1 (SLC39A1) knockout mice were generated by crossing Alb-Cre mice and SLC39A1^flox/flox mice. Liver samples were examined for inflammation, fibrosis, proliferation, and apoptosis. Mitochondrial mass, autophagy, ROS, and mitochondrial membrane potential (MMP), were detected. Co-immunoprecipitation and molecular docking were used to identify protein interactions.

Results: SLC39A1 is highly expressed in relapsed HCC patients and negatively correlated with overall survival. Knockdown of SLC39A1 inhibited cell proliferation by arresting the cell cycle and promoted cell apoptosis, accompanied by suppressing autophagic flux. Mechanistically, SLC39A1 interacts with a member of the dynamin superfamily of GTPases dynamin-related protein 1 (DRP1), followed by facilitating mitochondrial fission and MMP reduction. Inhibition of DRP1 abolished SLC39A1-induced mitochondrial division and MMP depolarization, while overexpression of DRP1 reversed mitochondrial fusion and MMP hyperpolarization in SLC39A1 silenced cells, accompanied by recuperative cell proliferative ability. SLC39A1^flox/flox,Alb-Cre mice displayed fewer tumour numbers and less liver damage compared with SLC39A1^flox/flox mice. A specific peptide targeting SLC39A1 to disturb the combination of full-length SLC39A1 and DRP1 efficiently suppressed HCC progression.

Conclusions: Our findings reveal a key role of SLC39A1-DRP1 interaction in HCC progression by disturbing mitochondrial quality control and providing a competitive peptide as a potential anti-tumour therapy.