Search Results (66)

The urokinase plasminogen activator or urokinase is a highly specific extracellular protease involved in numerous physiological and pathological processes. Its activity is a consequence of its interplay with its inhibitor, PAI1, and receptor, uPAR, and is finely regulated at several levels. The aim of the work was to investigate whether endoplasmic reticulum stress can modulate urokinase activity. Two tumor cell lines grown in cell culture were treated with Thapsigargin and sodium salicylate, inducers of ER stress response. Urokinase activity was determined in the conditioned media, and expression of uPA system molecules and molecules involved in response to ER stress in cell lysates was measured. ER stress influenced urokinase activity: while in the glioblastoma line its activity was increased, in breast cancer cells it was decreased. Differences in activity were a consequence of urokinase and PAI1 expression at the protein and RNA level. However, ER stress decreased cell migration, invasion, and proliferation regardless of the changes in urokinase activity. Gene expression analysis indicated that cell specific activation of some transcription factors and pathways could be responsible for different urokinase activity regulation. Full article

Urokinase plasminogen activation system regulates the activation of plasminogen to produce the ubiquitous extracellular protease plasmin. It is involved in different physiological and pathophysiological processes, which involve tissue reorganization, wound healing, cell migration and invasion, etc. The system comprises urokinase plasminogen activator, an extracellular protease, its inhibitor plasminogen activator inhibitor PAI1 and urokinase receptor, uPAR. The system is regulated at the level of transcription and posttranscriptionally, and the net urokinase activity depends on the balance between urokinase and PAI1. Promoters of urokinase, PAI1 and uPAR are regulated through different signaling pathways, mostly MAP kinases and TGFβ signaling. Urokinase promoter is complex and mostly depends on strong enhancers containing AP1/ETS binding sites for different combinations of AP1 dimers, whose members are phosphorylated through ERK, JNK and p38 kinases. The PAI1 promoter is mainly regulated through TGFβ signaling, which can use both Smad and AP1-dependent transcription. The uPAR promoter also depends on AP1 signaling, in addition to other transcription factors activated through other pathways. Although activated through common pathways, each of the promoters has specific regulation as a consequence of a signaling network, which enables fine-tuning of the system and urokinase activity according to the physiological needs. Full article

Background: Triple-negative breast cancer (TNBC) is associated with poor prognosis and limited targeted treatment options. The urokinase plasminogen activator receptor (uPAR) contributes to tumor aggressiveness and may be regulated by microRNAs such as miR-221. This study aimed to evaluate the prognostic relevance of uPAR mRNA and miR-221 expression in TNBC. Methods: uPAR mRNA and miR-221 expression levels were quantified by real-time PCR in tumor tissues from 101 patients with TNBC. Associations with clinicopathological parameters and disease-free survival (DFS) were analyzed using univariate and multivariable Cox regression models. In silico analyses of publicly available datasets were performed for validation and, in addition, for further miR-221 target prediction. Results: In both univariate and multivariable analyses, high uPAR mRNA expression was associated with shorter DFS, whereas, in contrast, elevated miR-221 expression correlated with improved DFS. No inverse correlation between uPAR and miR-221 expression was observed, making a direct regulatory miR-221/uPAR axis in TNBC unlikely. Still, combined analysis revealed a pronounced additive prognostic effect, with high uPAR and low miR-221 expression identifying patients with the poorest DFS. These findings were supported by in silico analysis with publicly available patient data. Finally, other potential miR-221 targets were identified by applying in silico target prediction. Conclusions: uPAR and miR-221 represent independent prognostic markers in TNBC. Their combined expression provides additional prognostic value for disease-free survival and supports their potential relevance as biomarkers and therapeutic targets in TNBC. Full article

Herbal melanin (HM), previously reported for its antiproliferative and pro-apoptotic properties, has garnered interest as a promising anti-colorectal cancer drug. However, HM’s biological effects and underlying molecular mechanisms and the related signaling pathways in colorectal cancer (CRC) cell motility are poorly investigated. To evaluate the impact of various concentrations (50, 100, and 200 μg/mL) of HM on cell migration, invasion, and tumorigenicity on human HT29 and SW620 CRC cell lines, a real-time cell analyzer instrument and colony formation assays were employed, respectively. An angiogenesis-related protein array was also used, and the levels of protein expression contributing to colony formation and extracellular proteolysis-driven cell migration and invasion, such as E-cadherin, N-cadherin and urokinase-type plasminogen activator receptor (uPAR), were monitored using Western blotting and RT-qPCR technologies. HM significantly decreased CRC cell motility, invasiveness, and formation of colonies, associated with E-cadherin upregulation and N-cadherin downregulation. In addition, HM specifically inhibited uPAR expression levels, which were also decreased by the pharmacological mitogen-activated protein kinase (MAPK) kinase (MEK) inhibitor UO126 and Jun N-terminal kinase (JNK) inhibitor SP600125, in both CRC cell lines, including metastatic CRC (mCRC) SW620 cell line. Addition of HM to cells pretreated with JNK and MEK inhibitors attenuated the blockade of JNK and ERK phosphorylation and alleviated HM-downregulated uPAR expression and HM-inhibited mCRC cell migration. In conclusion, our in vitro studies demonstrate that HM exhibits an inhibitory effect on CRC migration and invasiveness, associated with uPAR downregulation through JNK and ERK pathways. Full article

Background: Aberrant signalling through the urokinase-type plasminogen activator receptor (uPAR) is a key driver of tumour invasion and progression in prostate cancer, yet linking molecular-level perturbations to emergent spatial invasion phenotypes remains challenging. Methods: In this study, we developed a multiscale in silico framework combining molecular docking, mechanistic ordinary differential equation (ODE) modelling, and agent-based modelling (ABM) to investigate uPAR-driven invasion dynamics. Results: Molecular docking and MM-GBSA analyses were used to prioritise caffeic acid phenethyl ester (CAPE) as a candidate uPA/uPAR modulator, while uPAR inhibition was implemented mechanistically at the signalling level within the ODE model rather than through direct energetic parametrisation. Steady-state signalling outputs were mapped to effective proliferation and motility rates, which served as inputs to a spatial ABM of tumour invasion. The integrated simulations showed that uPAR inhibition results in statistically significant reductions in spatial invasion and tumour growth compared with baseline conditions, whereas enhanced uPA signalling produced only modest, non-significant trends. Conclusions: These findings demonstrate how subtle intracellular signalling perturbations can translate into pronounced population-level invasion phenotypes when embedded in a spatial context. Overall, the proposed digital-twin framework provides a coherent and extensible approach for connecting molecular prioritisation with quantitative predictions of tumour invasion behaviour in prostate cancer. Full article

Chondrosarcomas (ChSs) are mesenchymal chemo- and radiation-resistant tumors, representing the second most frequently diagnosed bone sarcoma after osteosarcoma and 20% of all bone sarcomas. Most of ChS patients have a good prognosis after complete surgical resection. Conversely, patients with inoperable disease, due to the tumor location or metastatic dissemination, represent a great clinical challenge due to the lack of effective therapeutic options. In this study, to the best of our knowledge, we document, for the first time in human ChS tissues, the existence of CD-31- and Podoplanin-negative vascular-like channels containing red blood cells, allowing us to hypothesize the occurrence of vasculogenic mimicry (VM) in ChSs. By using patient-derived ChS cells and a stabilized ChS cell line, we demonstrate that ChS cells are able to form in vitro tubules apparently similar to those formed by endothelial cells. Further characterization of these vessels revealed the pivotal role of the Urokinase Plasminogen Activator Receptor (uPAR) in mediating the capability of ChS cells to form VM. Finally, we provide evidence that, unlike bevacizumab, which did not exert any effect, the uPAR-derived antiangiogenic peptide RI-3 behaves as a potent inhibitor of VM. Full article

This review reappraises the anti-inflammatory potential of the contact activation system (CAS) in intensive care through an evolutionary lens. The authors propose that coagulation factor XII (FXII) and related components evolved in terrestrial animals as a “foreign-surface sensing–immunothrombosis” module, helping to explain the minimal bleeding phenotype of FXII deficiency and the secondary loss of F12 in marine mammals. CAS shares components with the kallikrein–kinin system (KKS): alpha-coagulation factor XIIa (α-FXIIa) drives coagulation factor XI (FXI) activation to amplify coagulation, whereas betacoagulation factor XIIa (β-FXIIa) activates the KKS to generate bradykinin, promoting vasodilation and vascular leak. Beyond proteolysis, zymogen FXII signals via urokinase-type plasminogen activator receptor (uPAR) to induce neutrophil extracellular trap formation (NETosis), thereby amplifying immunothrombosis. Clinically, the relevance spans sepsis and extracorporeal organ support: pathogens can hijack CAS/KKS to facilitate invasion, and artificial surfaces such as extracorporeal membrane oxygenation (ECMO) circuits chronically trigger contact activation. In animal models, selective inhibition of FXII/FXI prolongs circuit life and attenuates pulmonary edema and inflammation without materially increasing bleeding. The review also catalogs “non-coagulation” roles of CAS members: Activated coagulation factor XI (FXIa) modulates endothelial permeability and smooth-muscle migration, and the FXII heavy chain exhibits direct antimicrobial activity—underscoring CAS as a nexus for coagulation, inflammation, and host defense. Overall, CAS inhibitors may couple “safe anticoagulation” with “cascade-level anti-inflammation,” offering a testable translational path for organ protection in the ICU alongside infection control and informing combined, precision strategies for anticoagulation and anti-inflammatory therapy. Full article

The urokinase-type plasminogen activator receptor (uPAR) plays a pivotal role in regulating extracellular proteolysis, cell migration, immune responses, and tissue remodeling across diverse physiological and pathological contexts. This review provides detailed insights into the structure of uPAR, ligand interactions, and signaling mechanisms, emphasizing its central function in cancer progression, including tumor invasion, metastasis, angiogenesis, and modulation of the tumor microenvironment. We also summarize the involvement of uPAR as a key player in cardiovascular, infectious, and neurological diseases, where it contributes to inflammation, tissue damage, and disease progression. However, translational gaps remain, most notably inconsistent assay harmonization (especially for suPAR), uncertain context-specific cut-offs and patient-selection criteria and limited multicenter validation for uPAR-targeted imaging and therapeutics. This review addresses these gaps by synthesizing cross-disease evidence to clarify clinical use cases and outline practical selection frameworks. Furthermore, we discuss the clinical potential of uPAR as a diagnostic and prognostic biomarker in diverse disease contexts, along with recent advances in therapeutic strategies targeting uPAR. Full article

Autoimmune diseases arise from complex interactions of genetic, environmental, and hormonal factors, yet their precise causes remain elusive. Beyond its canonical role in fibrin degradation, the fibrinolytic system is increasingly recognized as both a pathogenic driver and a regulatory modulator in autoimmunity. Key factors—plasminogen (Plg), plasmin, α2-antiplasmin (α2AP), tissue-type plasminogen activator (tPA), urokinase-type plasminogen activator (uPA), its receptor (uPAR), and plasminogen activator inhibitor-1 (PAI-1)—not only reflect secondary responses to vascular and immune dysregulation but also actively shape innate and adaptive immunity. They influence macrophage activation, dendritic cell maturation, T cell responses, and cytokine production, thereby bridging coagulation, inflammation, and tissue repair. This review integrates current evidence on the dual pathogenic and regulatory roles of fibrinolytic factors, organizing autoimmune diseases into systemic, organ-specific, and secondary syndromes. We further discuss how the imbalance of fibrinolysis can either promote inflammatory persistence or, conversely, facilitate resolution through fibrin clearance and immune homeostasis. By highlighting this bidirectional influence, the review aims to refine our understanding of fibrinolytic components as both contributors to and regulators of autoimmune disease pathogenesis. Full article

Systemic sclerosis (SSc) is an autoimmune disease associated with a high burden of morbidity and mortality due to organ complications. Pulmonary arterial hypertension (PAH) and cardiac involvement, characterized by chronic right ventricular (RV) pressure overload with consequent RV dysfunction and ultimately right heart failure (HF), are among these. A common comorbidity in SSc is chronic kidney disease (CKD). CKD is often present at the time of PAH diagnosis or a decline in renal function may occur during the course of the disease. CKD is strongly and independently associated with mortality in patients with PAH and HF. The cardiovascular and renal systems are closely interconnected, and disruption of this balance may result in cardiorenal syndrome (CRS). Type 2 CRS refers to CKD as a consequence of chronic HF. In clinical practice, non-specific markers such as troponin, B-type natriuretic peptide (BNP), N-terminal pro-BNP (NT-proBNP), and serum creatinine aid in CRS diagnosis. More specific biomarkers, including cystatin C (CysC), neutrophil gelatinase-associated lipocalin (NGAL), galectin-3, and soluble urokinase plasminogen activator receptor (suPAR), have shown value for diagnosis and prognosis in CRS. This study aimed to evaluate comprehensively heart/kidney damage markers related to CRS in SSc patients compared with healthy controls (HC) and to examine their association with renal and cardiac ultrasound parameters. SSc patients showed significantly higher CRS markers than HC (p < 0.001). SSc patients with clinically diagnosed CRS had significantly elevated galectin-3, suPAR, sNGAL, and uNGAL levels (p < 0.05) than SSc patients without CRS. Positive correlations were found between renal resistive index (RRI) and NT-proBNP (r = 0.335, p < 0.05), and between RRI and suPAR (r = 0.331, p < 0.05). NT-proBNP, suPAR, galectin-3, sNGAL, and uNGAL emerge as promising biomarkers for the early detection of cardiac and renal involvement in SSc patients. Full article

Integrin αV (IαV) and the urokinase-type plasminogen activator receptor (uPAR) are key mediators of tumor malignancy in Glioblastoma. This study aims to characterize IαV/uPAR interaction in GBM and investigate the role played by glycans in this scenario. Protein expression and interaction were confirmed via confocal microscopy and co-immunoprecipitation. The role of N-glycosylation was evaluated using Swainsonine (SW) and PNGase F. IαV glycoproteomic analysis was performed by mass spectrometry. Sialic acids and glycan structures in IαV/uPAR interaction were tested using neuraminidase A (NeuA) and lectin interference assays, respectively. Protein expression and their interaction were detected in GBM cells, but not in low-grade glioma cells, even in cells transfected to overexpress uPAR. SW, PNGase, and NeuA treatments significantly reduced IαV/uPAR interaction. Also, lectin interference assays indicated that β1-6 branched glycans play a crucial role in this interaction. Analysis of the IαV glycosylation profile revealed the presence of complex and hybrid N-glycans in GBM, while only oligomannose N-glycans were identified in low-grade glioma. N-glycosylation inhibition and sialic acid removal reduced AKT phosphorylation. Our findings demonstrate, for the first time, the interaction between IαV and uPAR in GBM cells, highlighting the essential role of N-glycosylation, particularly β1-6 branched glycans and sialic acids. Full article

The role of the plasminogen activation system is to regulate the activity of the extracellular protease plasmin. It comprises the urokinase plasminogen activator (uPA), a specific extracellular protease which activates plasminogen, its inhibitor PAI1, and the urokinase plasminogen activator receptor, uPAR, which localizes the urokinase activity. The plasminogen activation system is involved in tissue remodeling through extracellular matrix degradation, and therefore participates in numerous physiological and pathological processes, which make it a potential biomarker. To investigate the role of these molecules in the cellular processes, we cloned human uPA, PAI1, and uPAR and overexpressed them in two cell lines, the glioblastoma line A1235 and the transformed human embryonal kidney cells HEK 293. We analyzed the urokinase activity and the expression of plasminogen activation system elements on the protein and RNA level by Western blot analysis and RTqPCR. Cell proliferation was followed up by cell counting, cell migration and invasion by wound-healing and the transwell assays, respectively, and cell adhesion and dispersal by spheroid formation. The cells transfected with urokinase sequence had increased urokinase activity and uPA expression, while the PAI1-transfected cells decreased urokinase activity, increased PAI1 expression, and decreased cell migration. HEK 293 cells expressing PAI formed only small spheroids. The effects of the uPA system molecules depended on their interactions with each other and with other molecules in the microenvironment, as well as on the cell-type-specific signaling. Full article

Rat dental pulp stem cells (DPSCs) can be used to elucidate mesenchymal stem cell (MSC) applications in regenerative medicine. However, information on rat DPSCs during long-term passage, which could lead to replicative senescence, is limited. In this study, we investigated the phenotypic changes in DPSCs after 3–26 passages (3P–26P). The results show that cell morphology and nuclear size increase proportionally with passage number. The phosphorylated histone H2A.X (γ-H2A.X) positive cells (indicating DNA damage) increased significantly earlier than the 4-Hydroxynonenal (4-HNE) stained cells (indicating an abundance of intracellular reactive oxygen species). Compared to the cells subjected to 3P and 5P, the cells subjected to 15P showed reduced proliferation despite being positive for Ki67. Furthermore, cell growth was completely arrested after 26P. The senescence markers, senescence-associated β-galactosidase (SA-β-gal) and p16, exhibited similar expression patterns that were not correlated with those of p21 and urokinase-type plasminogen activator receptor (uPAR). Nearly all cells expressed SA-β-gal and p16 after 26P, whereas only half expressed p21 and uPAR. These results will contribute to understanding the characteristics of DPSCs toward replicative senescence, which are applicable to elucidate mechanisms related to regenerative medicine and stem cell aging. Full article

Cervical cancer is a leading cause of gynecological malignancies and cancer-related deaths among women worldwide. This study investigates the anti-cancer activity of Thua Nao, a Thai fermented soybean, against HeLa cervical carcinoma cells, and explores its underlying mechanisms. Our findings reveal that the ethyl acetate fraction of Thua Nao (TN-EA) exhibits strong anti-cancer potential against HeLa cells. High-performance liquid chromatography (HPLC) analysis identified genistein and daidzein as the major isoflavones in TN-EA responsible for its anti-cancer activity. TN-EA and genistein reduced cell proliferation and induced G2/M phase arrest, while daidzein induced G1 arrest. These responses were associated with the downregulation of cell cycle regulators, including Cyclin B1, cycle 25C (Cdc25C), and phosphorylated cyclin-dependent kinase 1 (CDK-1), and the upregulation of the cell cycle inhibitor p21. Moreover, TN-EA and its active isoflavones promoted apoptosis in HeLa cells through the intrinsic pathway, evidenced by increased levels of cleaved Poly (ADP-ribose) polymerase (PARP) and caspase-3, loss of mitochondrial membrane potential, and the downregulation of anti-apoptotic proteins B-cell leukemia/lymphoma 2 (Bcl-2), B-cell lymphoma-extra-large (Bcl-xL), cellular inhibitor of apoptosis proteins 1 (cIAP), and survivin. Additionally, TN-EA and its active isoflavones effectively reduced cell invasion and migration by downregulating extracellular matrix degradation enzymes, including Membrane type 1-matrix metalloproteinase (MT1-MMP), urokinase-type plasminogen activator (uPA), and urokinase-type plasminogen activator receptor (uPAR), and reduced the levels of the mesenchymal marker N-cadherin. At the molecular level, TN-EA suppressed STAT3 activation via the regulation of JNK and Erk1/2 signaling pathways, leading to reduced proliferation and invasion of HeLa cells. Full article

EGFR-targeted therapies are efficacious, but toxicity is common and can be severe. Urokinase type plasminogen activator receptor (uPAR)-targeted drugs are only emerging, so neither their efficacy nor toxicity is fully established. Recombinant eBAT was created by combining cytokines EGF and uPA on the same single-chain molecule with truncated Pseudomonas toxin. Its purpose was to simultaneously target tumors and their vasculature in the tumor microenvironment. In prior studies on mice and dogs, the drug proved efficacious. Here, we report the safety of eBAT in normal wildtype, uPAR knockout, and immunoreplete and immunodeficient tumor-bearing mice, as well as in dogs with spontaneous sarcoma that more closely mirror human cancer onset. In immunocompetent mice, tumor-bearing mice, uPAR knockout mice, and mice receiving species-optimized eBAT, toxicities were mild and self-limiting. Likewise, in dogs with life-threatening sarcoma given dosages found to be biologically active, eBAT was well tolerated. In mice receiving higher doses, eBAT was associated with dose-dependent evidence of liver injury, including portal biliary hyperplasia, oval cell proliferation, lymphoplasmacytic inflammation, periportal hepatocellular microvesicular change, hemorrhage, necrosis, and apoptosis. The results support continuing the clinical development of eBAT as a therapeutic agent for individuals with sarcoma and other cancers. Full article