Spatial transcriptomics reveals tumor-derived SPP1 induces fibroblast chemotaxis and activation in the hepatocellular carcinoma microenvironment

Deciphering the cellular and molecular landscape of cervical cancer progression through single-cell and spatial transcriptomics

Cervical cancer represents a significant global health challenge, with complex cellular and molecular mechanisms driving its progression from HPV infection to invasive malignancy. This study employed an integrated approach combining single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics (stRNA-seq) to comprehensively characterize the tumor microenvironment (TME) across different stages of cervical cancer development. Through analysis of samples from normal cervix, HPV-infected normal cervix, high-grade squamous intraepithelial lesions (HSIL), and invasive cervical cancer, we identified distinct cellular populations and their dynamic changes during disease progression. Our findings revealed significant heterogeneity in immune cell populations, particularly highlighting the role of SPP1+ macrophages that were substantially enriched in cervical cancer compared to precancerous and normal tissues. Cell-cell communication networks and spatial mapping demonstrated that SPP1+ macrophages interact extensively with immune cells through the SPP1-CD44 signaling axis. This interaction contributes to an immunosuppressive microenvironment through modulation of T cell function and promotion of tumor cell survival. Furthermore, high expression of SPP1 correlated with advanced tumor stages and poor overall survival in cervical cancer patients, highlighting its potential as a prognostic biomarker. Our comprehensive characterization of the cellular landscape and intercellular communication networks in cervical cancer progression provides valuable insights for the development of targeted therapeutic strategies aimed at modulating the TME, particularly through disruption of the SPP1-CD44 axis. These findings establish a foundation for more effective personalized approaches to improve clinical outcomes in cervical cancer patients.

Ability of SPP1 to Alleviate Post-Intracerebral Hemorrhage Ferroptosis via Nrf2/HO1 Pathway

PURPOSE

This study aimed to investigate the role of secretory phosphoprotein 1 (SPP1/OPN) in modulating iron-induced cell death (ferroptosis) following intracerebral hemorrhage (ICH). By integrating transcriptomic analysis and experimental validation, we sought to identify key molecular pathways and therapeutic targets associated with ferroptosis in ICH.

METHOD

The Gene Expression Omnibus Series GSE24265 dataset was analyzed using the limma package (R platform) to identify differentially expressed genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) enrichment analyses were performed to elucidate biological functions. Genes associated with iron-induced mortality were identified by cross-referencing transcriptomic profiles with the FerrDb database. A protein-protein interaction network was constructed using Cytoscape, and hub genes were identified. An experimental ICH model was developed in mice using stereotactic instrumentation, and the effects of OPN administration were evaluated through neurological assessments, biochemical assays (superoxide dismutase, glutathione, malondialdehyde), Western immunoblotting (GPX4, ACSL4), Prussian blue histochemistry, and electron microscopy.

FINDING

Transcriptomic analysis identified 27 hub genes, with CD44 and ITGB3 characterized as receptors for OPN. In the ICH model, OPN administration improved neurological outcomes, elevated antioxidant markers, and reduced lipid peroxidation. OPN upregulated GPX4 while suppressing ACSL4, indicating anti-ferroptotic effects. These protective effects were mediated through the Nrf2 pathway, as confirmed by inhibitor ML385. Prussian blue staining and electron microscopy demonstrated reduced cerebral iron deposition and mitochondrial damage following OPN treatment.

CONCLUSION

This study provides novel evidence for SPP1/OPN as a key modulator of ferroptosis in ICH, highlighting its potential as a therapeutic target. By enhancing iron homeostasis and mitigating oxidative stress, OPN offers a promising strategy for improving outcomes in ICH patients.

The immunosuppressive role of MDSCs in HCC: mechanisms and therapeutic opportunities

Hepatocellular carcinoma (HCC) is a prevalent malignancy with a significant global burden. Despite substantial advancements in HCC treatment in recent years, therapeutic efficacy remains constrained by immune evasion mechanisms within the tumor microenvironment (TME). Myeloid-derived suppressor cells (MDSCs), as critical immunosuppressive elements of the TME, have garnered increasing attention for their role in tumor progression. Recent studies emphasize their central involvement in promoting immune evasion, tolerance, and immunosuppression in HCC. This review examines the contributions of MDSCs to HCC pathogenesis, elucidates their underlying mechanisms, and discusses ongoing clinical trials, emphasizing their potential as therapeutic targets for improving clinical outcomes.

Analysis of single-cell and spatial transcriptomics in TNBC cell-cell interactions

Triple-negative breast cancer (TNBC) is a highly malignant tumor in women, characterized by high morbidity, mortality, and recurrence rates. Although surgical treatment, radiotherapy, and chemotherapy are the mainstays of current treatment methods, the high heterogeneity of TNBC results in unsatisfactory outcomes with low 5-year survival rates. Rapid advancements in omics technology have propelled the understanding of TNBC molecular biology. The emergence of single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics (ST) has significantly enhanced knowledge of tumor heterogeneity and the distribution, functionality, and intercellular interactions of various cell types within the tumor microenvironment, including tumor cells, T cells, B cells, macrophages, and fibroblasts. The present study provides an overview of the technical characteristics of scRNA-seq and ST, highlighting their applications in exploring TNBC heterogeneity, cell spatial distribution patterns, and intercellular interactions. This review aims to enhance the comprehension of TNBC at the cellular level for the development of effective therapeutic targets.

Identification of the entosis-related prognostic signature and tumour microenvironment in hepatocellular carcinoma on the basis of bioinformatics analysis and experimental validation

Liver cancer ranks among the deadliest cancers worldwide. Entosis, a recently uncovered method of cell death, has not yet been fully explored for its relevance to HCC. A bioinformatics analysis was performed to determine the expression and mutational landscapes of Entosis-related genes (ERGs). A subset of differentially expressed Entosis-related genes (DEERGs) was generated. A risk model for entosis was subsequently constructed employing LASSO and Cox regression methodologies. The correlations among ERGs, genes associated with risk, the developed risk model, and the immune context of the tumour were explored. Furthermore, the study investigated the varying drug sensitivities between high-risk and slight-risk patient groups. The expression patterns of four pivotal risk genes were delineated via qRT‒PCR and WB. A prognostic model comprising four DEERGs (KIF18A, SPP1, LCAT and TRIB3) was developed. The ability of this model to predict the survival outcomes of patients with HCC was confirmed through receiver operating characteristic curve analysis. Patients were grouped according to their risk assessments, revealing that the low-risk population demonstrated a more favourable survival outcome than did the high-risk population. The high-risk population presented reduced tumour stroma, immune and ESTIMATE scores, along with an increased proportion of cancer stem cells and tumour mutation burden. Additionally, a connection between the risk model and the responsiveness of various chemotherapy drugs as well as the efficacy of immunotherapies in patients was noted. These findings provide significant guidance for the development of targeted clinical treatment strategies. qRT‒PCR and WB analysis revealed that the gene expression of KIF18A and SPP1 were elevated in HCCLM3 cells compared with that in THLE2 cells; whereas, the expression level of LCAT and TIRB3 was decreased. The four genes KIF18A, SPP1, LCAT and TRIB3 could effectively predict the survival prognosis of patients with liver cancer. KIF18A and SPP1 were elevated in HCC tissues compared with that in THLE2 cells.

Hepatic Arterial Flow-Induced Portal Tract Fibrosis in Portal Hypertension: The Role of VCAM-1 and Osteopontin-Expressing Macrophages

Background

The liver undergoes significant hemodynamic changes during surgery, transplantation, or cirrhosis with portal hypertension(PH). The hepatic artery buffer response(HABR), which compensates for reduced portal venous flow by increasing hepatic artery(HA) flow, is hypothesized to induce pathological portal tract remodeling. This study investigates the molecular mechanisms underlying this process.

Methods

PH was induced in Sprague-Dawley rats via partial portal vein ligation(PPVL). Structural evaluation(microCT), immune cell profiling, hemodynamic measurements, and transcriptomic analysis in macrophages(Mϕ) from sham or PPVL rats were conducted.

Results

MicroCT revealed decreased portal vein flow and increased HA flow correlated with portal pressure(r=0.799, p<0.01). A 2-fold increase in portal tract fibrosis(p<0.001) was observed with increased α-SMA+ myofibroblasts in PPVL rats. CD68+ Mϕ peaked at 10 days post-PPVL, and their depletion significantly reduced fibrosis(p<0.001), indicating critical roles of Mϕ in portal tract remodeling. VCAM-1 was elevated in HA endothelium and portal fibroblasts (PFs); VCAM-1 neutralization reduced collagen accumulation(p<0.05), CD68+ Mϕ(46.3%, p<0.01), and CD3+ T cells(18%, p<0.05). Mϕ-conditioned medium increased VCAM-1 in PFs(8-fold, p<0.001) and enhanced PF migration, while VCAM-1 knockdown reduced this effect (p<0.01). Single-cell RNA sequencing data(GSE171904) and RNA-FISH revealed increased interactions between osteopontin (Spp1)+ Mϕ and PFs, with Spp1+ Mϕ driving fibrosis. Spp1 knockdown in Mϕ co-culture reduced PF fibrogenic markers, while recombinant Spp1 upregulated Col1a1, Fn1, and Acta2 expression in PFs.

Conclusion

Increased VCAM-1 in arterial endothelial cells and PFs facilitates the recruitment of Spp1+ Mϕ, which drive HA flow-mediated vascular remodeling and portal tract fibrosis. These findings highlight arterial flow-induced fibrosis as a key mechanism in PH, potentially contributing to disease progression and decompensation.

Synopsis

Liver hemodynamic changes in portal hypertension drive extracellular matrix accumulation and portal tract remodeling via Spp1+ macrophages. This study highlights how altered blood flow induces fibrosis, and its potential role in decompensation, and identifies therapeutic targets for advanced liver disease.