Search Results (348)

Glioblastoma (GBM) is an extremely invasive and incurable tumor. We previously reported predominant ALDH1A3 expression at the invasive front of GBM tumors, which was associated with shorter patient survival, and further showed that ALDH1A3 promoted tumor angiogenesis involving plasminogen activator inhibitor-1 (PAI-1). Here, we investigated whether ALDH1A3 drives cell invasion through retinoic acid (RA) and PAI-1 signaling. Analysis of the TCGA-GBM dataset revealed a positive association between ALDH1A3 and PAI-1 (SERPINE1) expression. Overexpression of ALDH1A3 in GBM cells markedly increased PAI-1 mRNA and protein levels, with cellular colocalization of both proteins, accompanied by robust migration and invasion. These effects were reversed by treatment with a pan-RA receptor (RAR) antagonist AGN193109 (AGN), with a specific PAI-1 inhibitor tiplaxtinin (Tip) or by CRISPR/Cas9-mediated knockout of PAI-1. In a chick chorioallantoic membrane (CAM) model, ALDH1A3-overexpressing cells showed increased invasion, which was reduced by tiplaxtinin (Tip) treatment or PAI-1 knockout. Mechanistically, ChIP-qPCR demonstrated that RA treatment or ALDH1A3 overexpression increased RARα occupancy at the PAI-1 regulatory region, accompanied by increased PAI-1 expression, both of which were diminished by AGN. Collectively, the present study defines an ALDH1A3-RA-PAI-1 signaling axis that contributes to GBM cell motility and invasion. Full article

Background/Objectives: Protein misfolding and amyloid fibril formation underlie several degenerative diseases, including Alzheimer’s disease and Parkinson’s disease. Alpha-1 antitrypsin (A1AT), a serpin protein, is particularly prone to misfolding, with polymerization and aggregation implicated in alpha-1 antitrypsin deficiency and associated hepatic and pulmonary disorders. In this study, we examined the structural changes in A1AT induced by the fluorinated alcohol, trifluoroethanol (TFE), and assessed the inhibitory effects of two natural polyphenols, amentoflavone (AMF) and theaflavin (TF), on aggregation and fibril formation. Methods: A library of selected phytocompounds was virtually screened against the crystal structure of A1AT (PDB 3NE4) using AutoDock Vina to elucidate their binding affinity towards it. Based on binding affinities, two compounds, AMF and TF, were selected for further studies. Protein aggregation was induced with TFE, and the protective effects of AMF and TF were evaluated using protease inhibitory activity, intrinsic fluorescence, turbidity, Rayleigh scattering, ANS fluorescence, and ThT fluorescence assays. Furthermore, 100 ns molecular dynamics simulation and MM-PBSA calculations were performed to assess the stability and binding interactions of the A1AT–ligand complexes. Results: Pre-treatment of A1AT with AMF or TF significantly inhibited TFE-induced aggregation in a dose-dependent manner, with AMF being consistently more effective. ThT fluorescence analysis revealed a ~60–65% decrease in aggregate formation upon treatment with polyphenols, with IC₅₀ values estimated at ~40 µM for AMF and ~50 µM for TF, both of which are statistically significant. Molecular docking and 100 ns molecular dynamics simulation also revealed stable A1AT–polyphenol interactions, with AMF exhibiting greater binding affinity and greater attenuation of solvent-induced conformational perturbation. Conclusions: Collectively, our findings show that TFE causes A1AT misfolding via a molten globule-like intermediate, resulting in fibril formation at 30–40% TFE, and natural polyphenols AMF and TF inhibited aggregation in a concentration-dependent manner. These observations suggest the potential of AMF and TF as lead scaffolds for anti-aggregation strategies, as modulators of amyloidogenic processes. Full article

Nosema bombycis, the causal agent of silkworm pébrine disease, causes substantial economic losses to sericulturists annually. Previously, 19 serpin genes (NbSPNs) were identified in this parasite, but most of their functions remain unidentified yet. Here, we provide a functional and cellular characterization of NbSPN4 and NbSPN5. Bioinformatics tools predicted four cis-regulatory motifs in the promoter region of NbSPN genes. A yeast signal sequence trap (YSST) assay confirmed the computationally predicted N-terminal signal peptide for NbSPN4 but not for NbSPN5. Immunofluorescence assay revealed that NbSPN4 was localized to the nucleus and NbSPN5 to the cytoplasm of infected host BmE cells. Recombinant NbSPN4/5 proteins significantly inhibited host hemolymph melanization and phenoloxidase activity in vitro, demonstrating their immune-regulatory roles. These findings provide essential insights into the roles of NbSPNs in host–pathogen interactions during N. bombycis infection. Full article

Objective: This study aims to investigate the role of thrombospondin-1 (THBS1) in polycystic ovary syndrome (PCOS) pathogenesis and its mechanism in regulating granulosa cell (GC) function. Methods: Follicular fluid and granulosa cells from 21 PCOS patients and 21 age-matched non-PCOS controls were analysed for THBS1 expression and clinical correlations. A dehydroepiandrosterone (DHEA)-induced PCOS rat model with adeno-associated virus serotype 9 (AAV9)-mediated THBS1 knockdown was used to assess phenotypic changes. The KGN human granulosa-like cell line was employed to evaluate THBS1 overexpression effects on proliferation, apoptosis, and steroidogenesis. Mechanistic studies included RNA sequencing with Gene Set Enrichment Analysis (GSEA), co-immunoprecipitation, molecular docking against the latent TGF-β1 crystal structure (PDB 9VJJ), molecular dynamics simulation, an active/total TGF-β1 ELISA, and pharmacological TGF-β receptor inhibition. Results: THBS1 was elevated in PCOS follicular fluid and granulosa cells and correlated positively with serum AMH and LH after Benjamini–Hochberg FDR correction. AAV9-mediated ovarian THBS1 knockdown (37.4% protein reduction, p = 0.006) ameliorated cystic morphology, restored estrous cyclicity, and normalised serum AMH/LH/T. In KGN cells, THBS1 overexpression suppressed proliferation, induced apoptosis and inflammatory cytokines, and dysregulated steroidogenic enzymes. Transcriptome analysis revealed upregulation of canonical TGF-β/Smad pathway components (SERPINE1, SMAD7, TGFB2, INHBA, CCN2, COL1A1/2). Molecular docking and 100-ns dynamics simulation supported a stable interaction between THBS1 and latent TGF-β1 (ΔG_TOTAL ≈ −120 kcal·mol⁻¹). Co-immunoprecipitation confirmed physical association in cells, and ELISA showed elevated TGF-β1 in PCOS follicular fluid and rat serum, both attenuated by THBS1 knockdown. Pharmacological TGF-β receptor inhibition with SB-431542 rescued THBS1-induced cellular dysfunction. Conclusions: THBS1 is associated with PCOS-related granulosa cell dysfunction through the TGF-β/Smad pathway and represents a candidate biomarker and exploratory therapeutic target that warrants validation in independent multicentre cohorts. Full article

Background: MEIS proteins are essential homeobox transcription factors that play critical roles in development and have been increasingly implicated in oncogenesis, including breast cancer. Methods: In this study, we identified and characterized novel small-molecule MEIS2 inhibitors through in silico docking targeting the active region of the human MEIS2 homeobox domain. Lead candidates MEISi-2E, MEISi-3, and MEISi-4 were identified with binding energies ranging from −3.0 to −3.90 kcal/mol. The inhibitory potential of these molecules was validated in vitro using a species-conserved MEIS-Luciferase Reporter construct containing the TGACAG targeted locus. Results: Our results demonstrate that MEISi-2E, MEISi-3, and MEISi-4 significantly suppress MEIS-driven luciferase activity and downregulate the expression of Meis1, Meis2, and downstream genes such as IL17RB, CDH1, EGR2, PAX6, and SERPINE1 while upregulating negative regulator TGIF1 and SOX3. In breast cancer cell lines, these inhibitors exhibited potent growth inhibition, with MEISi-3 showing an exceptional IC50 as low as 0.1 μM in SK-BR-3 cells. Mechanistic studies using flow cytometry revealed that these inhibitors induce dose-dependent apoptosis and necrosis. Importantly, the novel inhibitors showed minimal toxicity to healthy human dermal and MRC5 fibroblasts, suggesting a favorable safety profile. Conclusions: These findings establish these small molecules as promising therapeutic candidates for targeting MEIS2-dependent pathways in breast cancer. Full article

Vasculogenic mimicry (VM) refers to the capacity of cancer cells from aggressive tumors to form a set of sinuses and channels that mimic normal blood vessels and lack endothelial cells. The rapid growth of a tumor leads to a deficiency in normal vessels, followed by poor oxygen and nutrient supply to tumor cells and VM induction. Understanding the mechanisms behind the development of the VM phenotype is important for the development of new anti-cancer therapies. Previous reports indicate that, during VM formation by melanoma Mel Z cells, about 2000 developmental genes undergo dramatic changes in expression. To identify genes more tightly linked to VM development, we compared the transcriptomes of Mel Z and MDA-MB-231 cells (triple-negative breast cancer cells), which also form VM. Most of the genes that change expression differ substantially between these two cell types. However, we identified 51 up- and 98 downregulated genes common to both cell lines. The non-overlapping groups of these genes are involved in regulating cell adhesion and proliferation. The group of common upregulated genes includes nine genes controlling blood vessel development and tube morphogenesis. Two genes in this group (BAK1 and SERPINE1) rapidly form numerous contacts with nucleoli during VM phenotype formation. We observed that knockdown of the SERPINE1 gene prevents the development of VM in Mel Z cells. Our data indicate that the formation of VM by aggressive cancer cells might be controlled by a special set of genes. Full article

Plasminogen activator inhibitor-1 (PAI-1), encoded by SERPINE1, is the principal physiological inhibitor of tissue-type and urokinase-type plasminogen activators and a central regulator of fibrinolysis. Beyond its canonical hemostatic role, PAI-1 has emerged as a pleiotropic mediator of tissue remodeling, fibrosis, metabolic dysfunction, cancer progression, cellular senescence, and age-associated immune dysregulation. A central argument of this review is that PAI-1 should be understood not only as a downstream biomarker of aging-associated pathology, but also as an active effector linking senescence-associated secretory phenotype (SASP) signaling, chronic low-grade inflammation, impaired immune surveillance, fibrotic extracellular matrix remodeling, and a prothrombotic state. In this framework, PAI-1 may function as an immune-aging checkpoint: a molecular node through which senescent, stromal, malignant, and inflammatory cells reinforce immune evasion and tissue dysfunction. Structure-guided drug discovery has enabled the development of small-molecule PAI-1 inhibitors, including TM5275, TM5441, TM5509, and TM5614. Among these, TM5614 is an orally available investigational compound that has progressed to clinical evaluation. Preclinical studies support anti-thrombotic, anti-fibrotic, anti-inflammatory, anti-senescent, and tumor-microenvironment-modulating effects of PAI-1 inhibition, while early clinical studies have evaluated TM5614 in chronic myeloid leukemia, immune-checkpoint-refractory malignant melanoma, non-small-cell lung cancer, and COVID-19-associated pneumonia. This review summarizes the biology of PAI-1, expands the discussion of immunoaging, reviews representative preclinical and clinical data, compares available PAI-1 inhibitors, and discusses the translational opportunities and safety considerations for TM5614 and related compounds. Full article

Inflammatory bowel diseases, particularly ulcerative colitis (UC), are chronic relapsing inflammatory disorders with limited therapeutic options. The zinc-finger transcription factor ZBTB4 has been implicated in the initiation and progression of cancer, but its role in UC remains unknown. Here, we found that ZBTB4 deficiency exacerbates dextran sulfate sodium (DSS)-induced colitis in C57BL/6J male mice. Compared with the wild type, ZBTB4 deficiency increases weight loss, colon shortening and proinflammatory cytokine production. RNA-seq analysis revealed that ZBTB4 deficiency enhances Serpine1 expression and activates the NF-κB pathway. NF-κB inhibition by JSH-23 alleviated the effect of ZBTB4 deficiency on DSS-induced colitis. These results imply the protective role of ZBTB4 in UC. Through an integrated drug screening, we identified a natural sesquiterpene lactone, handelin, as a potential compound to enhance ZBTB4 expression in NCM460 cells. Handelin administration relieved colitis in wild-type mice but produced no effect in ZBTB4 knockout mice, demonstrating that its anti-colitic effect depends on ZBTB4 expression. Collectively, our results indicate the key role of ZBTB4 in UC and ZBTB4 agonists may serve as a novel approach for UC treatments. Full article

High-altitude hypoxic adaptation in mammals involves complex molecular mechanisms, with non-coding RNAs (ncRNAs) increasingly reported to participate in hypoxia-related regulation. However, the contribution of circRNAs in cardiac adaptation to chronic hypoxia remains largely unexplored. This study performed an integrative competitive endogenous RNA (ceRNA) analysis to investigate circRNA-mediated regulatory networks in the hearts of Tibetan pigs and Yorkshire pigs maintained under high- and low-altitude conditions, using four comparison groups (TH, TL, YH, and YL). Using Ribo-Zero RNA sequencing, we identified 961 circRNAs in heart tissues, with 358 differentially expressed circRNAs (DE-circRNAs) detected across the four groups. Functional enrichment analysis revealed that their host genes were associated with hypoxia-related pathways, including HIF-1, VEGF, AMPK, and autophagy, critical for energy metabolism and mitochondrial function. A HIF-1-specific ceRNA network was constructed, identifying key axes including circDUSP16–ssc-miR-671-5p–CAMK2A, circTLK1–ssc-miR-331-3p–SERPINE1, and circTLK1–novel-miR-624–ENO1. JASPAR analysis predicted potential HIF-1α binding sites in the promoters of ENO1, SERPINE1, and CAMK2A, supporting their regulatory roles. These findings provide a transcriptomic overview of circRNA expression patterns in pig heart tissues under different altitude conditions and prioritize candidate ceRNA relationships for further functional investigation. Full article

Objectives: This study aimed to elucidate the multi-target therapeutic mechanisms of Camellia sinensis phytochemicals in periodontitis using an integrative multi-scale molecular modeling strategy. Methods: An integrated in silico strategy was employed, incorporating network-based pharmacological analysis, protein interaction network evaluation, molecular docking assessment, density functional theory (DFT) computations, molecular dynamics (MD) trajectory analysis, MM/PBSA-derived binding energy estimation, and residue-level energetic contribution profiling. Overlapping targets between C. sinensis and periodontitis-associated genes were identified, followed by topological screening to determine crucial hub proteins. The most promising target was subjected to detailed structural and energetic evaluation. Results: Intersection analysis identified 23 common targets, with AKT1, myeloperoxidase (MPO), MMP2, MMP3, MMP9, STAT1, IL2, BCL2, ESR1, and SERPINE1 emerging as central hubs. Functional enrichment highlighted AGE–RAGE and JAK–STAT signaling pathways and extracellular matrix remodeling processes. Docking revealed MPO as the most favorable core target. Gallate-containing catechins, particularly (−)-gallocatechin gallate (−9.63 kcal/mol) and gallocatechin 3-O-gallate (−9.52 kcal/mol), exhibited more favorable binding affinities than the standard inhibitor 4-ABAH (−6.02 kcal/mol). DFT analysis demonstrated moderate HOMO–LUMO gaps (4.31–4.78 eV) and favorable dipole moments supporting electronic stability and reactivity. MD simulations confirmed stable complex formation over 100 ns, with persistent hydrogen bonding and consistent ligand retention. MM/PBSA calculations further validated a favorable binding of (−)-gallocatechin gallate (−27.66 ± 7.53 kcal/mol) and gallocatechin 3-O-gallate (−26.09 ± 8.96 kcal/mol), comparable to or exceeding 4-ABAH (−25.88 ± 4.44 kcal/mol). Conclusions: C. sinensis phytochemicals, particularly gallate-containing catechins, exhibit stable, energetically favorable interactions with MPO, supporting their potential as competitive inhibitors that modulate oxidative stress and inflammatory pathways in periodontitis. Full article

(1) Aim: The incidence of high-altitude pulmonary hypertension (HAPH) has risen in recent years and is expected to continue increasing; however, its diagnosis remains challenging. In this study, we employed proteomics and metabolomics to identify the proteins and metabolic biomarkers that contribute to the development of HAPH. (2) Methods: We applied integrated proteomics and metabolomics to match blood samples from 40 HAPH patients and 40 healthy controls in Yunnan’s high-altitude regions to characterize molecular profiles, identify biomarkers, and develop a predictive model. (3) Results: Proteomic analysis identified four proteins (A2IPH7, K1C14, PSME2, SERPINE2) commonly dysregulated in HAPH patients from two high-altitude regions. SERPINE2 was notably downregulated and showed a negative correlation with clinical severity, which was further validated in HAPH rat lung tissues and supported by UK Biobank data for idiopathic PAH. Concurrent metabolomics uncovered 11 shared metabolites, largely acyl fatty acids, enriched in pathways such as unsaturated fatty acid synthesis. Integration of these multi-omics data enabled the development of a robust predictive model. (4) Conclusion: Our study identified key protein and metabolic biomarkers involved in HAPH development, which were validated in animal models. Based on these findings, a predictive model was developed, highlighting SERPINE2 and 11 metabolites as promising targets for the prediction and prevention of HAPH. Full article

Background: High-grade soft tissue sarcomas (STSs) are heterogeneous tumours lacking robust prognostic or predictive biomarkers. Regnase-1, an immune RNase, enhances antitumour immunity by limiting immunosuppressive tumour microenvironment (TME) components (e.g., myeloid-derived suppressor cells (MDSCs)), but remains unexplored in STS. As CD68⁺ tumour-associated macrophages (TAMs) drive TME suppression and poor prognosis in non-translocation-driven STS, we evaluated Regnase-1 and CD68⁺ TAMs to assess Regnase-1 as an indicator of an immunologically activated TME. Methods: Immunohistochemistry scoring of Regnase-1 and CD68⁺ TAMs was performed in 91 patients. Overall survival (OS) was assessed by Kaplan–Meier and Cox regression, and findings were validated in an independent “The Cancer Genome Atlas” Sarcoma (TCGA-SARC) cohort (n = 212). Results: In UPS, Regnase-1-high predicted longer OS (17.0 months vs. not reached; p = 0.0247) and lower mortality (univariate hazard ratio (HR) = 0.3; p = 0.0343; multivariate HR = 0.4; p = 0.0413), but not after radiotherapy. CD68⁺ TAM-high predicted shorter OS (13.0 months vs. not reached; p = 0.0274) and higher mortality (HR = 2.0, 95% CI 1.1–3.7; p = 0.0325). Both Regnase-1 effects were reproduced in TCGA-SARC. Regnase-1-high tumours showed inflammatory/interferon enrichment, reduced TGF-β signalling, and SERPINE1 upregulation. Conclusions: Regnase-1 marked a pro-inflammatory TME and favourable outcome in UPS, but this effect may reverse upon radiotherapy. Full article

Microcystin-LR (MC-LR) is a potent hepatotoxin that has been shown to cause liver damage even at doses lower than the established Low Observable Adverse Effect Level (LOAEL) of 200 μg/kg in animal models. We have previously observed that low-dose exposure to MC-LR in animals with diet-induced Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) and subsequent treatment with antioxidants like N-acetylcysteine (NAC) and the Na⁺/K⁺ ATPase-Src kinase inhibitor pNaKtide significantly alleviated hepatic infiltration of immune cells, downregulated markers of inflammation and hepatotoxicity, increased the breakdown of the toxin molecule, and restored phase I and II drug metabolism pathways, including the glutathione pathway. Because the liver is composed of heterogeneous cell types, this study aimed to determine the specific role of hepatocytes in the uptake and metabolism of MC-LR, especially in the setting of MASLD. To address this, we used two well-established hepatocyte cell lines—AML-12 murine hepatocytes and human Hep3B hepatocytes. Preliminary dose comparison studies with AML-12 cells showed that MC-LR at 10 μM concentration showed a significant upregulation in the genetic expression of the markers of hepatotoxicity—OSMR (p ≤ 0.01) and SerpinE (p ≤ 0.0001)—in comparison to Vehicle. Treatment with pNaKtide (1 µM) and/or NAC (10 mM) in the presence of MC-LR significantly reduced the expression of both OSMR (p ≤ 0.0001) and SerpinE (p ≤ 0.01 and p ≤ 0.0001, respectively). To model steatotic hepatocytes characteristic of the MASLD phenotype, Hep3B hepatocytes were first treated with 500 µM of oleic acid (OA) before exposing them to the toxin in the presence and absence of antioxidants. MC-LR exposure, induced markers of inflammation and hepatotoxicity to be elevated significantly in the presence of OA as compared to MC-LR exposure alone. This elevation of the genetic markers of inflammation and hepatotoxicity was significantly attenuated on treatment with pNaKtide (1 µM) and NAC (10 mM). Quantification of human SERPINE1 (PAI1) and 8-OHdG, a stable marker of oxidative stress, in the spent media of Hep3B cells corroborated the trends observed in the genetic markers of hepatotoxicity. These observations support the central role that hepatocytes play in the uptake and metabolism of MC-LR, which is complicated by the presence of MASLD-like conditions and can help in the development of future therapeutic strategies. Full article

Background/Objectives: Late-onset Alzheimer’s disease (LOAD) is a multifactorial neurodegenerative disorder involving the interaction of genetic and environmental factors. Dysregulation of the fibrinolytic system, particularly an increase in plasminogen activator inhibitor-1 (PAI-1) levels, may contribute to Alzheimer’s pathology. Vitronectin (VTN) regulates fibrinolysis by stabilizing PAI-1. This study investigated the relationships between plasma PAI-1 activity and VTN, SERPINE1 (PAI-1), and APOE gene variants in nineteen LOAD patients (>65 years) and ten cognitively normal age-matched control groups. Methods: Targeted next-generation sequencing was used to analyze the VTN, APOE, and SERPINE1 genes in 19 LOAD patients and ten controls. Additionally, plasma PAI-1 activity was measured in both groups. Results: Plasma PAI-1 activity was statistically significantly higher in LOAD patients compared to controls (p = 0.04). Targeted next-generation sequencing results showed that VTN 5′-UTR variants (rs7212814, rs1555584131, rs71135830, and rs11437594) were found in all patients and observed in 20% of controls (p = 0.0001). The VTN rs704 variant was detected in 84% of patients and 29% of controls (p = 0.001). VTN 5′-UTR variants showed Spearman correlation with PAI-1 activity (r = 1.0; p < 0.0001). SERPINE1 3′-UTR variants (rs11178, rs41423845) were found to be associated with the disease (p = 0.027; p = 0.0001). The APOEε3/ε4 genotype was present in 52.6% of patients and was not associated with PAI-1 activity. VTN variants showed an association with LOAD. Conclusions: These findings suggest that VTN variants may contribute to LOAD pathogenesis by affecting PAI-1 and leading to fibrinolytic system dysregulation. Full article

Osteosarcoma (OS), the most prevalent primary malignant bone tumor with a dismal prognosis, exhibits significant heterogeneity in programmed cell death (PCD) pathways, but its subtype-specific functional mechanisms remain poorly characterized. This study integrated PCD-related gene signatures to delineate molecular subtypes in OS via consensus clustering, successfully defining four distinct subtypes with divergent prognostic outcomes and immune microenvironments. Differential expression, functional enrichment, and protein–protein interaction (PPI) network analyses revealed subtype-specific PCD pathway associations (e.g., lysosome-dependent cell death, apoptosis, pyroptosis and anoikis), while comparative immune profiling and clinical characterization further refined subgroup identities. A robust prognostic risk model incorporating five pivotal genes (SERPINE2, CBS, SQLE, UBE2D4, and S100A13) and metastasis status demonstrated superior predictive performance in both training and external validation cohorts. These findings not only elucidate the functional architecture of PCD across OS molecular subtypes but also establish a clinically actionable model for precision risk stratification and tailored therapeutic strategies. Full article