Search Results (505)

Sepsis, which affects 49 million people yearly, killing 11 million of them, is known to induce severe liver dysfunction. It is characterized by extensive metabolic reprogramming, resulting in acute metabolic loss of function and maladaptive repair that can prime the organ for fibrosis rather than functional regeneration. To understand how intercellular communication dictates these outcomes, we performed cell type-specific bulk RNA-sequencing on hepatocytes (HEP), hepatic stellate cells (HSCs), liver sinusoidal endothelial cells (LSECs), Kupffer cells (KC), and CD45⁺ leukocytes (CD45) from mice following polymicrobial sepsis. Cell-cell communication analyses using CellChat and NicheNet revealed a clear reorganization of the hepatic environment. While HSCs remain largely quiescent during homeostasis, after sepsis, they become the liver’s central signaling hub and broadcast potent fibrogenic and chemotactic signals (e.g., Ccl7) to surrounding cells. This actively suppresses hepatocyte metabolic functions, promotes leukocyte infiltration, and may further initiate early fibrogenic priming. Our findings highlight HSCs as regulators during septic acute liver injury, revealing communication nodes that could be targeted to constrain fibrosis responses and promote normal functions and repair. Full article

Background: Angiogenesis is critical for tumor progression. Microvessel density (MVD) is commonly assessed using CD31 and CD34, which detect both mature and newly formed vessels and therefore cannot distinguish active neoangiogenesis from stable, quiescent vasculature. Nestin, an intermediate filament protein expressed preferentially in proliferating endothelial cells, has been proposed as a complementary marker of active angiogenesis and has been investigated in several solid tumor types, including pancreatic, colorectal, and breast carcinomas. However, no studies have quantitatively compared nestin-positive MVD across AK, BCC, and SCC using standardized methods. Methods: Immunohistochemistry for nestin, CD31, and CD34 was performed on 118 patient samples collected in 2015–2019 and diagnosed with AK, BCC, or SCC. MVD was quantified by averaging vessel counts in three representative “hot spot” areas. Results: Nestin-positive MVD was significantly lower in patients with AK compared to patients with BCC and SCC (p < 0.001). The mean MVD of nestin-positive vessels was significantly lower in AK than in BCC and SCC (p < 0.0001). In all three groups, nestin-positive MVD demonstrated a strong, positive correlation with both CD34 and CD31. Conclusions: Nestin-positive MVD was significantly elevated in BCC and SCC compared to AK lesions and demonstrated strong correlations with standard angiogenic markers. These findings suggest that nestin may warrant further investigation as a complementary marker of angiogenesis in non-melanoma skin cancer. Whether nestin-positive MVD offers independent diagnostic or prognostic value in this context remains to be determined in larger, prospective, multicentre studies. Full article

Background: Quiescent cancer cells (QCCs) evade conventional therapies and contribute to minimal residual disease (MRD) and relapse, yet the signaling pathways governing their survival remain poorly understood. Methods: Here, we performed integrative proteomic and phosphoproteomic profiling of triple-negative breast cancer (TNBC) cells transitioning between proliferation and serum removal-induced quiescence, followed by re-stimulation. Results: We identified dynamic remodeling of both proteome and phosphoproteome, with quiescent cells showing downregulation of mitotic drivers and upregulation of extracellular matrix components. Notably, phosphorylation of CK2 substrates was increased during quiescence, and CK2 inhibition using CX-4945 impaired cell survival under nutrient and genotoxic stress, disrupted autophagy, microtubule dynamics, and protein synthesis. Phospho-enrichment and functional assays identified death-associated protein kinase 3 (DAPK3) as a CK2-regulated effector mediating stress-induced apoptosis. In silico analysis confirms a link between high CK2 expression and poor chemotherapy response in basal breast cancer. Conclusions: These findings establish CK2 as a critical survival kinase in QCCs and a potential therapeutic target for MRD eradication in breast cancer. Full article

Epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) has historically been regarded as a therapeutically uniform entity, characterized by marked sensitivity to EGFR tyrosine kinase inhibitors (TKIs) and limited responsiveness to immune-checkpoint inhibitors (ICIs). However, accumulating clinical and translational data suggest heterogeneity within EGFR-mutant NSCLCs. In particular, patients whose tumors express high levels of programmed death-ligand 1 (PD-L1) consistently experience inferior outcomes with EGFR-TKI monotherapy, including earlier progression and reduced response durability, even with third-generation EGFR-TKIs. This review synthesizes clinical, molecular, and immunologic evidence supporting the hypothesis that EGFR-mutant NSCLC with high PD-L1 expression may represent a biologically distinct phenotype. Key findings include data from retrospective cohorts, real-world analyses, and translational studies showing high PD-L1 expression to be associated with attenuated oncogene addiction, increased genomic complexity, tumor cell plasticity, and a dysfunctional but non-quiescent immune microenvironment. Notably, in this context, PD-L1 expression does not reliably predict benefit from ICIs but, rather, serves as a marker of aggressive tumor biology and early resistance to EGFR-TKI therapy. Lastly, we discuss the therapeutic implications of these observations, outlining the rationale for biomarker-informed, risk-adapted treatment strategies, including EGFR-TKI-based combinations, while emphasizing the need for careful integration of immunotherapy and prospective validation. Full article

Notably, certain ginsenoside components exhibit distinct bidirectional and context-dependent regulatory effects on ferroptosis depending on the disease setting. In aberrantly proliferating or activated cells, ginsenosides function as ferroptosis inducers, whereas in damaged quiescent cells of normal tissues, they act as ferroptosis inhibitors. The pro-ferroptotic effect is predominantly observed in cells characterized by abnormal proliferation or activation, such as cancer cells and activated hepatic stellate cells in liver fibrosis. In this context, ginsenosides modulate key iron metabolism proteins and suppress antioxidant defense systems (e.g., GPX4, SLC7A11), thereby triggering intracellular iron overload and explosive lipid peroxidation, ultimately culminating in ferroptosis. Conversely, the anti-ferroptotic effect primarily targets damaged non-proliferative cells in normal tissues subjected to pathological insults (e.g., ischemia–reperfusion, inflammation). In this setting, the regulatory focus of ginsenosides shifts toward maintaining iron homeostasis through mechanisms including upregulation of iron storage proteins (e.g., FTH1), downregulation of iron uptake proteins (e.g., TFRC), and inhibition of labile Fe²⁺ accumulation, thereby blocking ferroptosis initiation. This review systematically elucidates the pharmacological effects and underlying mechanisms by which different ginsenoside components regulate ferroptosis across various disease contexts and cell types, with particular emphasis on their disease- and cell type-dependent bidirectional regulatory characteristics. By highlighting these context-specific effects, we aim to provide novel potential therapeutic targets and mechanistic insights for the precision treatment of diverse pathological conditions, including malignant proliferative disorders, non-malignant aberrantly activated/proliferative diseases such as liver fibrosis, and cell injury/degenerative diseases. Full article

Background: The progression of idiopathic pulmonary fibrosis (IPF) involves distal airway remodeling and bronchiolization; however, the mechanisms driving these changes, particularly the contributions of epithelial stem cells, are not fully understood. K13⁺ hillock cells, normally quiescent in proximal airways, were examined for their potential contribution to IPF pathogenesis. Methods: Spatial immunofluorescence was used to profile K13 expression along the airway axes in IPF and control lungs. Multiplex staining complemented by ex vivo culture assays was used to test expression stability. Single-cell RNA-sequencing (scRNA-seq) data were re-analyzed to identify cell subclusters and pathway enrichments. Meanwhile, cell–cell communication was inferred by using CellChat. Results: K13 was ectopically upregulated in IPF honeycomb cysts, triggering a proximal-like pseudostratified phenotype. This shift was marked by surges in K13⁺ regionally overlapping expression patterns (K5⁺, ~9%; CC10⁺, ~53%; ACE-TUB⁺, ~44%; MUC5AC⁺, ~23%) and a decline in SOX2 expression (~95% to ~64%), with ~70% of residual SOX2^low cells exhibiting elevated K13. Accompanying the expansion of K13⁺ subclusters (basal: 1.8% to 41.5%; club: 10.7% to 31.5%), it was observed that the profibrotic markers (K17, S100A2, LGALS7, IGFBP6) and ontologies related to RNA processing, stress response, and senescence were also enriched. These subclusters also amplified pro-fibrotic signaling (e.g., TGF-β, SEMA3, and GALECTIN-9) associated with epithelial subtypes and HAS1^high fibroblasts. Conclusions: Here, we demonstrate that K13⁺ cell activation is a pivotal event, driving the dysregulated proximalization of distal airways in IPF through fate reprogramming and epithelial-mesenchymal crosstalk. Thus, elucidating these K13-mediated fate dynamics provides a critical framework for understanding IPF pathogenesis. Full article

The SERPINE1 gene encodes the serine protease inhibitor plasminogen activator inhibitor type-1 (PAI-1), a major negative regulator of the plasmin-dependent pericellular proteolytic cascade and a crucial determinant in the program of stromal remodeling. Recent omics approaches confirmed that high tumor SERPINE1 levels are prognostic for poor disease outcomes and shorter disease-free survival in various malignancies. Kinetic analysis of biomarkers of cell cycle transit in growth-synchronized p53 dual mutant human keratinocytes confirmed that PAI-1 transcription occurred early after growth activation of quiescent (G₀) cells and prior to G1 entry. Previous evidence has confirmed that differential residence of USF family members (USF1→USF2 switch) at the PE2 region hexanucleotide E box motif (CACGTG) in the SERPINE1 proximal promoter characterizes the G₀→G₁ transition period and the transcriptional status of the SERPINE1 gene. A consensus PE2 E box motif (5′-CACGTG-3′) at nucleotides −566 to −561 is required for USF occupancy of the PE2 E box and serum-stimulated SERPINE1 transcription. Interference with USF2 occupancy of the PE2 E Box site by a double-stranded PE2 “decoy”, or induced expression of a dominant-negative USF (A-USF) construct, attenuate serum- and TGF-β1-stimulated SERPINE1 synthesis. Tet-Off activation of an A-USF insert reduced both PAI-1 and PAI-2 transcripts while increasing the fraction of proliferating (Ki-67⁺ cells). Conversely, overexpression of USF2 or adenoviral delivery of a PAI-1 vector inhibited HaCaT colony expansion. These findings are discussed in this review and collectively suggest that the USF1→USF2 transition at the PE2 E box site and subsequent SERPINE1 transcription impact serum-stimulated keratinocyte growth and, likely, cell cycle progression. Full article

Eosinophils are multifunctional granulocytes with central roles in the pathobiology of chronic airway diseases. While systemic eosinophilia (>300 cells/μL) is a well-established biomarker to guide therapeutic decision-making, accumulating evidence indicates that eosinophils are not a uniform population but instead exhibit substantial phenotypic and functional heterogeneity across biological compartments, inflammatory states, and disease contexts. In this review, we synthesize the current understanding of eosinophil heterogeneity in airway diseases and critically evaluate the strengths and limitations of surface marker-based approaches, with emphasis on CD62L/L-selectin-defined subpopulations. Although CD62L-based stratification has provided valuable insight into eosinophil activation and tissue localization, its limited specificity, inconsistent clinical associations, and reliance on murine models restrict its utility as a framework for eosinophil subtyping in humans. We highlight how transcriptomic and proteomic profiling has transformed the field by revealing that peripheral blood eosinophils are largely quiescent, whereas disease-relevant functional specialization is predominantly acquired within inflamed tissues in response to cues from the local microenvironment. These molecular studies support a model in which eosinophil heterogeneity represents a continuum of activation rather than discrete, fixed subsets. A refined, integrative approach to understanding eosinophil heterogeneity is critical for improving patient stratification, predicting therapeutic responsiveness, and optimizing precision medicine strategies in chronic airway diseases. Full article

Cervical Intervertebral Disc Degeneration (CIVDD) involves significant microenvironmental physical stiffening, forcing nucleus pulposus cells (NPCs) into a rigid phenotype via F-actin over-assembly. It remains unclear if cyclic tensile strain (CTS) can reverse this physical stiffening, particularly in severe degeneration. This study stratified 18 patients into Mild, Moderate, and Severe cohorts based on MRI. Primary NPCs were subjected to physiological 5% CTS (1 Hz, 24 h). Atomic Force Microscopy (AFM) and immunofluorescence were utilized to evaluate Young’s modulus and cytoskeletal remodeling. Results demonstrated that baseline cellular stiffness increased significantly with degeneration severity. Following CTS, all groups exhibited universal de-stiffening and F-actin depolymerization. Crucially, a “Degeneration Paradox” emerged: the Severe group displayed the highest relative elastic modulus recovery rate, significantly surpassing the Mild group. This microscopic recovery correlated inversely with preoperative disc height loss and range of motion. We conclude that severely degenerated cells are not metabolically quiescent but “physically locked” by a rigid cytoskeleton. Physiological CTS restores compliance via mechanical unloading, confirming that severe cells retain superior relative mechanoplasticity and may benefit from mechanotherapy-based “unlocking” strategies. Full article

Background: Hepatocellular carcinoma (HCC) stands as a prevalent global health issue with increasing incidence and mortality rates. Hepatocellular carcinoma (HCC) exhibits profound molecular and clinical heterogeneity, which limits the effectiveness of current therapeutic strategies. Circadian rhythm disruption has been implicated in metabolic reprogramming, proliferation, and immune modulation in cancer, but its role in shaping HCC heterogeneity remains poorly defined. Methods: Four public HCC transcriptomic cohorts (TCGA-LIHC, CHCC, LIRI, LICA) were integrated using RMA normalization and ComBat for batch correction. Consensus clustering based on 31 core circadian clock genes (CCGs) identified robust molecular subtypes. Multi-omics characterization—including genomic alterations, pathway activity (GSEA/GSVA), immune microenvironment profiling (CIBERSORT, EPIC, MCP-counter, xCell), and drug-sensitivity prediction (pRRophetic/oncoPredict)—was performed to delineate subtype-specific biological properties. A nine-gene CCG-based RiskScore model was constructed using LASSO Cox regression to internally validate subtype robustness and intra-subtype risk stratification. Results: Using consensus clustering of 31 core CCGs in TCGA-LIHC and three independent validation cohorts (CHCC, LIRI, LICA), we identified three reproducible subtypes—Cluster-1 (metabolic–quiescent), Cluster-2 (transition–intermediate), and Cluster-3 (proliferation–inflammatory)—which were recapitulated across cohorts and showed distinct overall survival (Cluster-3 worst; log-rank p values significant across datasets). Multi-omic characterization revealed that Cluster-3 exhibits the highest tumor mutational burden and CNV burden with enrichment of TP53/AXIN1/TERT alterations, strong activation of cell-cycle, E2F, and G2M programs, and an immune-hot yet immunosuppressed microenvironment enriched for TAMs, Tregs and MDSCs. By contrast, Cluster-1 shows relative genomic stability, dominant hepatic metabolic signatures (fatty-acid oxidation, bile-acid and xenobiotic metabolism) and an immune-cold phenotype. Single-cell mapping linked ALAS1 expression to malignant hepatocytes predominating in Cluster-1, whereas NONO and CSNK1D localized to stromal (CAFs/TECs) and both malignant/immune compartments respectively in Cluster-3, providing a cellular mechanism for subtype-specific metabolism, angiogenesis and immune modulation. Finally, a nine-gene CCG-based RiskScore validated prognostic stratification and drug-sensitivity predictions indicated subtype-specific therapeutic vulnerabilities (notably increased predicted TKI sensitivity in Cluster-3). Conclusion: In conclusion, this study proposes a robust circadian rhythm-based molecular classification of hepatocellular carcinoma, revealing three biologically and clinically distinct subtypes characterized by divergent genomic alterations, metabolic programs, immune microenvironment states, and prognostic patterns. By integrating bulk and single-cell transcriptomic data, we identify subtype-specific roles of key circadian regulators—including ALAS1, NONO, and CSNK1D—in shaping tumor metabolism, proliferation, stromal remodeling, and immune suppression. These findings highlight circadian dysregulation as a potential upstream factor associated with HCC heterogeneity and provide a conceptual framework for developing subtype-tailored mechanistic studies and circadian-informed therapeutic strategies. Full article

Glioblastoma stem cells (GSCs) function as dynamic regulators of tumor persistence, maintained by interconnected genetic, epigenetic, metabolic, and microenvironment-derived circuits. Rather than fixed entities, GSCs continuously recalibrate their functional state as transcriptional regulators, chromatin architecture, and non-coding RNA networks shift in response to microenvironmental cues. Hypoxic, vascular, and immune niches reinforce these adaptive states by stabilizing HIF signaling, modulating cytokine gradients, and sustaining immunosuppression. Metabolic flexibility further supports survival under therapeutic and environmental stress. Standard therapies inadvertently activate these same resilience pathways: TMZ enhances DNA repair and quiescent survival, while radiation promotes mesenchymal transition and immune evasion, thereby enriching GSC-associated circuits that drive recurrence. Understanding how these molecular circuits converge to sustain stemness, plasticity, and microenvironmental crosstalk highlights the need for combinatorial strategies that simultaneously disrupt epigenetic gating, metabolic rewiring, ncRNA-controlled repair, and niche-dependent signaling to achieve durable glioblastoma control. Full article

Targeted therapies and chemoimmunotherapy have transformed outcomes for non–small cell lung cancer (NSCLC), yet relapse remains common. Resistance is increasingly recognized to include an early, largely reversible phase in which a minor subpopulation survives lethal therapy through non-genetic adaptation. These drug-tolerant persister (DTP) cells may be quiescent or cycling, and provide a reservoir from which stable, genetically resistant clones can later emerge. In parallel, late recurrence may reflect tumor dormancy, in which disseminated or residual cells persist for prolonged periods under microenvironmental constraint and/or immune surveillance. This review integrates DTP and dormancy frameworks in NSCLC, summarizes mechanisms that sustain persistence (chromatin and transcriptional plasticity, stress signaling, metabolic rewiring, and stromal/immune protection), and highlights experimental models and translational readouts, including circulating tumor DNA (ctDNA)–based minimal residual disease (MRD) monitoring. We also discuss potential therapeutic concepts to prevent DTP formation, exploit persister liabilities, or enforce dormancy in minimal-disease settings. A mechanistically grounded understanding of these survival programs is essential for rational combinations and biomarker-guided trials aimed at durable remission. Full article

Late metastatic relapses still represent a major clinical challenge in breast cancer, particularly in hormone receptor-positive (HR+) disease, with dormant disseminated tumor cells (DTCs) playing a critical role in driving late metastatic relapses. In fact, these cells can persist in a quiescent, non-proliferative state in metabolically hostile microenvironments such as the bone marrow, where they can resist conventional therapies, driving metastatic relapses even years after primary tumor removal. Recent advances highlight the crucial role of lipid metabolism in protecting dormant DTCs from ferroptosis—a form of regulated cell death characterized by iron-dependent lipid peroxidation. Dormant DTCs can avoid lipid peroxidation by incorporating monounsaturated fatty acids (MUFAs) into membrane phospholipids through ACSL3 and SCD1 activity, while accumulating lipid droplets (LDs) that sequester oxidizable polyunsaturated fatty acids (PUFAs), thus limiting the substrates available for ferroptosis. In parallel, antioxidant systems such as the GPX4–glutathione axis further prevent lethal lipid-derived reactive oxidative species (ROS) accumulation. This review highlights the central role of lipid metabolism, redox regulation and ferroptosis resistance in dormant DTCs; it also explores emerging therapeutic opportunities to overcome dormancy-associated resistance and reduce late relapse risk in breast cancer. Full article

Endothelial integrity is essential for cardiovascular health, and circulating endothelial progenitor cells, particularly endothelial colony-forming cells (ECFCs), are key contributors to vascular repair and maintenance. Long non-coding RNAs (lncRNAs) have emerged as novel epigenetic regulators of endothelial physiology and pathology. Building on our previous work identifying the lncRNA KLRK1-AS1 as a positive modulator of ECFC wound healing, we aimed to elucidate its role in endothelial biology. Cord blood-derived ECFCs were subjected to siRNA-mediated silencing of KLRK1-AS1, followed by blinded evaluations of monolayer morphology, barrier stability using ECIS impedance measurements, assessments of proliferation, and spheroid-based angiogenic activity. SiRNA-mediated silencing of KLRK1-AS1 induced detectable alterations in ECFC monolayer morphology (p = 0.047), while proliferation remained unaffected. Notably, KLRK1-AS1 knockdown significantly compromised endothelial barrier integrity, resulting in a 44% reduction in impedance after 48 h (p < 0.001), suggesting weakened intercellular contacts. In contrast, loss of KLRK1-AS1 enhanced angiogenic behaviour, demonstrated by an increased number of sprouts (+62%, p = 0.031). Together, these findings indicate that KLRK1-AS1 supports a quiescent, stable endothelial phenotype, with intact barrier function, while its depletion shifts ECFCs toward a more angiogenic, activated state. Our results identify KLRK1-AS1 as a previously unrecognised regulator of endothelial function. Full article

Quiescence is a reversible, non-proliferative cellular state that enables survival under nutrient limitation while preserving the capacity to resume growth. Rather than representing a passive default, quiescence is an actively regulated program conserved from unicellular eukaryotes to metazoans. This review focuses on the nuclear mechanisms underlying quiescence entry, maintenance, and exit, with primary emphasis on mechanistic insights from yeast models while highlighting conserved principles in multicellular systems. Across species, quiescence is characterized by global transcriptional repression, chromatin compaction, and the extensive reorganization of nuclear architecture, coordinated by nutrient-sensing pathways centered on TOR/mTOR signaling. We discuss how transcriptional reprogramming is achieved through redistribution of RNA polymerases, dynamic transcription factor activities, and large-scale remodeling of histone modifications, alongside repressive chromatin formation. In parallel, post-transcriptional mechanisms—including intron retention, alternative polyadenylation, and accumulation of non-coding RNAs—fine-tune gene expression while limiting biosynthetic output. We further examine how changes in nuclear organization, such as nucleolar condensation, condensin-mediated chromosome rearrangements, and telomere hyperclusters, support long-term viability and genome stability. Collectively, this review highlights nuclear dynamics as an integrative regulatory layer that links metabolic state to cellular identity, adaptability, and long-term survival, with broad implications for development, stem cell function, and disease. Full article