Clinical and Translational Medicine最新文献

Lysozyme (LYZ) is a naturally occurring antimicrobial protein first discovered in the 1920s. As a key component of innate immunity, its antimicrobial effects and immunomodulatory functions in bacterial defence have been extensively characterized. However, emerging evidence since the 1950s has revealed its complex involvement in tumour progression, with conflicting reports of both tumour-suppressive and tumour-promoting effects across different cancer types. A critical knowledge gap remains in understanding the mechanistic basis for this duality, exacerbated by reliance on single-omics approaches and small cohorts in previous studies. This review focuses on mammalian C-type LYZ (referred to as LYZ hereafter unless specified) and integrates multi-omics data (transcriptomics and proteomics) with clinical and mechanistic research to systematically dissect its dual roles in cancer. By analysing cross-cancer heterogeneity through multi-omics perspectives, we emphasize its dual promise as both a prognostic biomarker and an actionable therapeutic target, aiming to provide new insights for precision oncology.

Key points

Background

Subarachnoid haemorrhage (SAH), a devastating subtype of stroke, is predominantly caused by the rupture of intracranial aneurysms. Emerging evidence indicates that the risk of intracranial aneurysm rupture correlates with elevated serum levels of fatty acids and pro-inflammatory cytokines. Moreover, increased serum concentrations of adipocyte fatty acid-binding protein (A-FABP), an inflammation-related adipokine, have been associated with poorer prognosis in SAH. However, the precise roles of A-FABP in SAH pathogenesis and its biomarker potential in cerebrospinal fluid (CSF) remain unclear.

Methods

CSF from 40 SAH patients and 30 controls was analysed by targeted fatty acid metabolomics. Experimental SAH mice were induced by endovascular perforation in both genetic deletion and pharmacological inhibition of A-FABP. Brain injury was quantified by neurobehavioural test, inflammatory cytokine expression and TUNEL staining. In vitro, conditioned medium from fatty acid-stimulated microglia was applied to primary neurons to evaluate apoptosis. Microglial metabolic reprogramming was assayed with Seahorse XF assays.

Results

CSF revealed significant metabolic disruption in SAH, characterized by arachidonic acid (AA), linoleic acid and palmitic acid (PA). Enrichment analysis implicated A-FABP plays a crucial role in SAH pathogenesis. Notably, elevated A-FABP levels independently predicted increased SAH severity and poorer prognosis. In mice model of SAH, A-FABP was significantly upregulated in microglia. Genetic deletion and pharmacological inhibition of A-FABP significantly ameliorated brain injury, including neurological deficits, neuroinflammation and neuronal apoptosis. Mechanistically, PA and AA promoted BV2 microglial inflammation via an A-FABP-dependent manner, subsequently inducing apoptosis in co-cultured primary neurons. Moreover, A-FABP inhibition reprogrammed microglial metabolism, enhancing fatty acid β-oxidation and energy supply. Proteomics further identified the JAK2/STAT3 as a downstream pathway of A-FABP-mediated neuroinflammation.

Conclusions

A-FABP is a promising biomarker and translatable therapeutic target to improve SAH outcome. Targeting A-FABP disrupts fatty acids–driven neuroinflammation and microglial metabolic reprogramming to reduce brain injury after SAH.

Background

Lymph node (LN) metastasis is a well-established independent prognostic factor in head and neck squamous cell carcinoma (HNSCC). Formation of suppressive tumour immune microenvironment (TIME) is a major contributor to tumour immune evasion and metastasis. However, the TIME landscape underlying LN-metastatic HNSCC remains poorly elucidated.

Methods

A total of 688 866 single-cell transcriptomes across 212 HNSCC samples were integrated. Comprehensive bioinformatic analyses on single-cell RNA sequencing and microarray datasets revealed a TREM2⁺ tumour-associated macrophage (TAM) cluster associated with LN metastasis. The functional role of TREM2⁺ TAMs was investigated through multiplex immunohistochemistry (mIHC) staining in clinical HNSCC cohort and in vitro co-culture experiments. Furthermore, machine learning algorithms were employed to construct a prognostic model for HNSCC.

Results

Integrative single-cell analysis revealed the immunosuppressive TIME of LN-metastatic HNSCC, characterised by high infiltration of exhausted CD8⁺ T cells (CD8⁺ Tex). We identified a specific TREM2⁺ TAM cluster that was strongly associated with CD8⁺ Tex infiltration and LN metastasis. In vitro experiment confirmed that TREM2⁺ TAMs promoted CD8⁺ T cell exhaustion. Mechanistically, TREM2⁺ TAMs exhibited a terminally differentiated phenotype driven by ETV5, and secreted SPP1 to interact with CD44 on CD8⁺ T cells, thus upregulating BHLHE40 to promote CD8⁺ Tex formation. Clinically, a prognostic model based on TREM2⁺ TAM signature genes was trained to independently predict HNSCC outcomes.

Conclusions

This study delineates the mechanism that TREM2⁺ TAMs promote LN metastasis in HNSCC by facilitating CD8⁺ T cells exhaustion via SPP1–CD44–BHLHE40 axis, proposing TREM2⁺ TAMs as potential therapeutic target for HNSCC.

Background

Efferocytosis is a critical physiological process in which phagocytes clear apoptotic cells to maintain tissue homeostasis. However, within the tumour microenvironment (TME), this process is systematically hijacked by tumour cells, transforming it into a key pathological mechanism that drives immunosuppression, tumour progression and therapeutic resistance.

Key findings

This review systematically elucidates the central role of metabolic reprogramming in this functional reversal, emphasising that efferocytosis is essentially an immunometabolic intersection process precisely regulated by metabolism. By releasing various metabolites such as ATP, lactate, adenosine and sphingosine-1-phosphate (S1P), apoptotic tumour cells not only recruit tumour-associated macrophages (TAMs) but also metabolically pre-program their functions, inducing polarisation towards a pro-tumourigenic M2-like phenotype. During the recognition stage, tumour cells exploit metabolic abnormalities, such as glycosylation and lipid oxidation, to modify surface ‘eat-me/don't-eat-me’ signals, thereby hijacking macrophage recognition and engulfment programs. Upon completion of engulfment, systemic reprogramming of amino acid, lipid and glucose metabolism occurs within macrophages. These metabolic alterations synergistically lock their immunosuppressive phenotype and establish a metabolic symbiosis between the tumour and stromal cells.

Conclusions

Based on these mechanisms, this review further explores translational strategies targeting the efferocytic–metabolic axis, aiming to reprogram the immunosuppressive efferocytosis into immune-activating events to overcome TME-mediated immunosuppression and enhance current therapeutic efficacy. By deeply dissecting the metabolic regulatory networks of efferocytosis, we aim to pave new directions for cancer immunotherapy, achieving a paradigm shift from ‘metabolic hijacking’ to ‘metabolic interventional therapy’.

The prognostic relevance of HLA class I (HLA-I)-mediated immunity in cancer immunotherapy remains unclear. We introduce deltaHED, a novel metric that quantifies evolutionary divergence between germline and tumour-acquired HLA-I alleles, integrating both inherited and somatic immunogenetic variation. Using whole-exome sequencing, we analysed deltaHED across three independent cohorts: 164 patients with recurrent/metastatic nasopharyngeal carcinoma (RM/NPC) from the POLARIS-02 trial (PD-1 monotherapy), 88 melanoma patients receiving PD-1 monotherapy, and 477 esophageal squamous cell carcinoma (ESCC) patients from the JUPITER-06 trial (PD-1 plus chemotherapy vs. chemotherapy alone). High deltaHED was significantly associated with increased tumour mutational burden and neoantigen load (p < .001), but predicted worse progression-free survival (PFS) and overall survival (OS) in patients receiving PD-1 blockade across all three cancers. In ESCC, this association was observed only in the immunotherapy arm, not in patients treated with chemotherapy alone. High deltaHED also correlated with increased mutations in antigen-processing and T-cell receptor pathways. These findings establish deltaHED as a clinically relevant biomarker of immune divergence with potential to improve patient stratification and guide personalised immunotherapy strategies.