Search Results (113)

Chronic inflammatory signaling contributes to cartilage degeneration across multiple joint diseases, yet the molecular consequences of sustained cytokine exposure remain incompletely understood. We investigated how prolonged interleukin-1β (IL-1β) stimulation remodels the chondrocyte proteome and whether these changes are associated with senescence-associated traits. Primary human articular chondrocytes were exposed to IL-1β (10 ng/mL) for up to four days. Time-resolved data-independent acquisition (DIA) proteomics was integrated with immunofluorescence, quantitative PCR, multiplex metalloproteinase profiling, BrdU incorporation, growth-curve analysis, and senescence-associated β-galactosidase assays. Sustained IL-1β induced extensive time-dependent proteomic remodeling, with early inflammatory and extracellular matrix responses followed by alterations in cell-cycle regulation and cytoskeletal organization. Prolonged stimulation was associated with persistent downregulation of CDK4, Cyclin D1, DNA replication-associated proteins, and Rho GTPase-associated components, accompanied by actin cytoskeletal remodeling. These molecular changes were associated with impaired proliferation, increased senescence-associated β-galactosidase activity, and transient modulation of p21. Following cytokine withdrawal, BrdU incorporation showed partial recovery. Together, these findings indicate that sustained IL-1β progressively reshapes the chondrocyte cellular state through coordinated remodeling of proliferative, cytoskeletal, and metalloprotease programs while showing some degree of proliferative plasticity under the conditions tested. Full article

Melanoma is a highly aggressive and invasive form of skin cancer that arises from the uncontrolled growth of melanocytes. It is characterized by early spread through the lymphatic system and metastasis. The success of metastasis is linked to the ability of melanoma and other cancer cells to resist anoikis, a type of cell death that occurs when cells lose their adhesion to the extracellular matrix. Redox signaling plays an essential role in anoikis resistance. The balance between intracellular levels of nitric oxide (NO) and the reactive oxygen species (ROS) O₂⁻ and H₂O₂ stimulate signaling pathways related to proliferation and survival or cell death. A375 and SK-MEL-28 human melanomas cell lines, representing primary melanoma and lymph node metastatic melanoma cells, respectively, under suspension and adherent culture conditions were used to investigate the redox regulation of anoikis resistance. Both cell lines express the three isoforms of nitric oxide synthases (NOS) and NADPH oxidase 4 (NOX4) as endogenous sources of NO and ROS, respectively. When A375 cells in suspension were treated with the pan-NOS inhibitor L-NAME, their viability decreased. The treatment resulted in a decrease in FAK phosphorylation at Tyr397 and in ERK 1/2 phosphorylation. The expression of FAK, ERK 1/2, β-actin, and α-tubulin were significantly reduced. Treatment with L-NAME led to an increase in the expression of the metalloprotease MMP-9. SK-MEL-28 cells in suspension and treated with the NOX4 inhibitor, GKT36901, exhibited reduced viability. This was accompanied by the inhibition of FAK phosphorylation at Tyr397, ERK 1/2 phosphorylation, and a reduction in the expression of FAK, ERK 1/2, β-actin, and α-tubulin, with a slight elevation in the expression of MMP-9. Migration and invasion were strongly inhibited in A375 cells upon treatment with L-NAME, while treatment with GKT36901 had a marginal effect on the migration and invasion capacities of SK-MEL-28 cells. In summary, melanoma cells employ nitrosative and oxidative stress to shield themselves from anoikis. Nitric oxide was essential for melanoma cells at the primary site for resisting anoikis, while H₂O₂ contributed to anoikis resistance in metastatic melanoma cells. Full article

Osteoarthritis (OA) is a multifactorial disease characterized by inflammation, extracellular matrix remodeling, and joint degeneration, and it still lacks disease-modifying treatments. Here, we applied an ex vivo OA model based on transwell co-cultures of cartilage and synovial membrane explants harvested from OA patients to compare the effects of adipose-derived stem/stromal cell (ASC) conditioned medium (CM) with dexamethasone (DEX), a clinically used corticosteroid. Explants were treated for 48 h with 100 nM DEX, CM derived from 5 × 10⁵ ASCs, or left untreated. Outcomes included gene and protein expression of key mediators, metalloprotease and aggrecanase activities, and nitric oxide release. DEX significantly reduced inflammatory markers (e.g., PTGS, IL-1β, and IDO) and VEGF expression in both tissues, while CM did not elicit consistent anti-inflammatory effects. Regarding matrix remodeling, both treatments reduced metalloprotease activity, with DEX modulating MMP3 and MMP13 expression in both tissues and CM reducing only MMP3 expression in cartilage while presenting high levels of TIMP-1. These results confirm the robustness of the model, demonstrated by reproducible responses to DEX and its high-throughput potential, and underscore the need for mechanistic studies to optimize novel biotherapeutics. Full article

The premetastatic niche (PMN) represents a specialized microenvironment established in distant organs before the arrival of metastatic cells. This concept has fundamentally altered our understanding of cancer progression, shifting it from a random event-driven process to an orchestrated one. This review examines the critical role of extracellular proteases in PMN formation, focusing on matrix metalloproteinases (MMPs), serine proteases, and cysteine cathepsins that collectively orchestrate extracellular matrix remodeling, immune modulation, and vascular permeability changes essential for metastatic colonization. Key findings demonstrate that MMP9 and MMP2 facilitate basement membrane degradation and the recruitment of bone marrow-derived cells. At the same time, tissue inhibitor of metalloproteinase-1 (TIMP-1) promotes organ-specific hepatic PMN recruitment through neutrophil recruitment mechanisms. The plasminogen–plasmin system emerges as a master regulator through its broad-spectrum proteolytic activity and ability to activate downstream proteases, with S100A10-mediated plasmin generation providing mechanistic pathways for remote PMN conditioning. Neutrophil elastase and cathepsin G contribute to the degradation of anti-angiogenic proteins, thereby creating pro-metastatic microenvironments. These protease-mediated mechanisms represent the earliest interventional window in metastatic progression, offering therapeutic potential to prevent niche formation rather than treat established metastases. However, significant methodological challenges remain, including the need for organ-specific biomarkers, improved in vivo methods for measuring protease activity, and a better understanding of temporal PMN dynamics across different target organs. Full article

Background: Following myocardial infarction (MI), cardiac fibroblasts (CFs) adopt distinct phenotypes to ensure scar formation and healing. Although leukocytes are a critical driver of post-MI healing, the role of neutrophils in modulating CF phenotype remains insufficiently explored. We therefore investigated the impact of soluble mediators released by neutrophil subtypes found post-MI—pro-inflammatory (N1) and anti-inflammatory (N2)—on shaping CFs phenotype. Methods: In vitro, human 3D grown CFs were indirectly co-cultured with N1 or N2 neutrophil-like cells using a two-chamber Transwell system. After 24 h, expression of inflammatory, remodeling, and pro-fibrotic markers was evaluated in fibroblasts and conditioned media. In vivo, soluble mediators derived from polarized mouse neutrophils (SN1 or SN2) were injected into the infarcted myocardium of C57BL/6J after MI surgery. The effects on the healing process were investigated at 1 and 7 days post-MI. Results: In vitro, CFs were found to exhibit a pro-inflammatory and matrix-degrading phenotype following indirect co-culture with N1 cells, characterized by overexpression of IL-1β, IL-6, MCP-1, and metalloproteases MMP-3/MMP-9. In vivo, both SN1 and SN2 treatments significantly reduced pro-inflammatory markers IL-1β and IL-6 gene expression at day 1 post-MI (inflammatory phase). At day 7 post-MI (resolution phase), SN1/SN2 treatments continued to limit local inflammation, while mitigating fibrotic remodeling by reducing CCN2, α-SMA, and key extracellular matrix proteins. Conclusions: Together, these findings suggest that while N1-derived mediators promote a pro-inflammatory fibroblast phenotype in vitro, factors secreted by both N1 and N2 support a more balanced reparative response in vivo, by limiting local inflammation and potentially mitigating adverse remodeling post-MI. Full article

Matrix metalloproteases (MMPs) are zinc-dependent endopeptidases that are critical for extracellular matrix (ECM) remodeling, with key roles in tissue development and repair, and immune responses. Despite their evolutionary and functional importance, the diversification and regulatory dynamics of MMPs genes in teleosts remain poorly understood. This study investigates the evolutionary history of MMPs with collagenolytic activity in the vertebrates with an emphasis on teleosts. Using comparative genomics and phylogenetics we identified conserved single-copy mmp2 and mmp9 genes and duplicated mmp11 and mmp13 paralogs in all non-salmonid teleosts. Phylogenetic and synteny analyses suggest that mmp11 paralogs originated from the teleost-specific genome duplication (TSGD), whereas the origin of mmp13 paralogs originated from a more complex evolutionary scenario. Protein domain analysis confirmed conserved catalytic motifs across species, supporting functional retention. The expression patterns of paralog genes were studied in two model marine teleosts, the Sparus aurata (gilthead sea bream) and Dicentrarchus labrax (European sea bass). Developmental and adult tissue transcriptome analyses revealed three major expression patterns among the paralogs: similar expression, stage-specific or tissue-specific expression. The overall data point to varied evolutionary dynamics of MMP genes in the teleosts, tracing their origin to different whole-genome duplication events. Expression profiles on paralog genes in model teleosts suggest regulatory sub-functionalization as the most possible fate of retained MMPs paralogs in teleosts following whole-genome duplication. Full article

Therapeutic strategies targeting “tumor-educated platelets” (TEPs) and platelet–tumor interactions by key signaling pathways (ITAM, P2Y12) may reduce metastasis and cancer. Using a TEP gene expression dataset originally created to study swarm intelligence-enhanced detection of lung cancer cells (GSE89843), we did perform extensive transcriptome analysis to integrate these data with directed protein–protein interactions and build a TEP-specific signaling network. We analyze network topology and controllability and identify critical and indispensable nodes, as well as high-weight, usually high-score nodes. We reconstruct (pharmacological) controllable subnetworks of TEP signaling, which we then explore for drugs targets. We found 111 upregulated and 108 downregulated genes compared to control platelets, enriched in pathways related to extracellular matrix interactions, cytoskeleton organization, immune signaling, and platelet activation. Ribosomal function, apoptosis, and immune signaling were among the downregulated processes, highlighting unique TEP profiles in non-small-cell lung cancer (NSCLC). Our integrative analysis of TEPs in NSCLC reveals key transcriptional and network-based alterations harmful for the cancer patient. Using four complementary strategies, we identified five high-confidence genes (Gene symbols always given throughout the paper), ITGA2B, FLNA, GRB2, FCGR2A, and APP, as central to TEP signaling. These can be targeted by FDA-approved drugs. Fostamatinib, an SYK inhibitor, emerged as the top candidate drug to disrupt ITAM-mediated platelet activation selectively; metastasis-promoting metalloprotease and cytoskeletal targets influencing adhesion were also identified. A low-dose combination therapy of fostamatinib, Aducanumab, and acetylsalicylic acid (aspirin) may control TEP effects. In conclusion, our preclinical in silico approach revealed FDA-approved drugs that allow therapeutic targeting of metastasis-promoting TEPs and target NSCLC at the same time. Full article

Metarhizium anisopliae, an entomopathogenic fungus, can produce four extracellular proteases, subtilisin (Pr1), trypsin (Pr2), metalloproteases (Pr3), and cysteine proteases (Pr4), which are important for pathogenicity of M. anisopliae in target hosts. In order to understand their function in M. anisopliae pathogenicity, third-instar nymphs of Locusta migratoria were fed with a diet containing either conidia of M. anisopliae strain IPPM202 or in combination with one of the four inhibitors (TPCK: tosyl-phenylalanine chloromethyl-ketone, inhibitor of Pr1; EDTA: ethylenediaminetetraacetic acid, inhibitor of Pr3; APMSF: 4-amidinophenyl methanesulfonyl fluoride, inhibitor of Pr2; CI1: cathepsin inhibitor 1, inhibitor of Pr4). The effects on mortality, midgut integrity, and the gut enzymes peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and phenol oxidase (PO) were examined. The results indicated that exposure to IPPM202/TPCK and IPPM202/CI1 caused decreased mortality to L. migratoria with no loss of midgut epithelial cellular integrity. On the other hand, exposure to IPPM202/APMSF or IPPM202/EDTA mixtures resulted in higher mortality similar to PPM202, with severely damaged epithelial gut cells with fragmented microvilli, broken endoplasmic reticulum, and disrupted nucleus membrane. The activity of the protective enzymes POD, SOD, CAT, and PO all increased significantly when L. migratoria was treated with IPPM202 only, but decreased when any one of the inhibitors was added. We further concluded that TPCK, a subtilisin (Pr1) inhibitor, and CI1, a cysteine protease (Pr4) inhibitor, played important roles in the pathogenicity of the M. anisopliae strain IPPM202. Conversely, trypsin (Pr2) and metalloproteases (Pr3) did not have a role in the given process. We further concluded that trypsin (Pr2) and metalloproteases (Pr3) do not contribute to the fungal infection process, while the subtilisin (Pr1) inhibitor TPCK and cysteine protease (Pr4) inhibitor CI1 play critical roles in the pathogenicity of Metarhizium anisopliae strain IPPM202, thus providing a foundation for targeted biocontrol strategies. Full article

Particulate matter (PM), mainly PM_0.5, represents a significant concern for human health, particularly relating to lung homeostasis, and more research is required to ascertain its tissue tropism and the molecular pathways involved. In this study, we first focus on classical in vitro toxicological endpoints (cytotoxicity and cell growth) in human bronchial and alveolar epithelial cell lines mimicking the two pulmonary target tissues. Air samples were collected in five Italian cities (Brescia, Lecce, Perugia, Pisa, Turin) during winter and spring. To better decipher the PM_0.5 effects on pulmonary cells, a further winter sampling was performed in Brescia, and studies were extended to assess tumour promotion, oxidative stress, and the activity of Matrix metalloproteases (MMP). The results confirmed that the effect of air pollution is linked to the seasons (winter is usually more cytotoxic than spring) and is correlated with the peculiar characteristics of the cities studied (meteoclimatic conditions, economic/anthropogenic activities). Alveolar cells were often less sensitive than bronchial cells. All PM samples from Brescia inhibited intercellular communication mediated by gap junctions (GJIC), increased the total content in glutathione, and decreased the reduced form of glutathione, whereas the Reactive Oxygen Species (ROS) content was almost constant. Long-term treatments at higher doses of PM decreased MMP2 and MMP9 activity. Taken together, the results confirmed that PM is cytotoxic and can potentially act as tumour promoters, but the mechanisms involved in oxidative stress and lung homeostasis are dose- and time-dependent and quite complex. Full article

(1) Objective: Cardiovascular diseases (CVD) are one of the main entities responsible for the progressive increase in morbidity and mortality worldwide. Some of the biomarkers involved in these processes are matrix metalloproteases (MMPs) and disintegrants and metalloproteases (ADAMS), produced by multiple tissues and whose main function is the excessive degradation of the extracellular matrix (ECM). The aim of this study is to describe the existing literature on the role of MMP in the pathophysiology of CVD and its usefulness in clinical practice for the diagnostic and therapeutic approach. (2) Methods: A systematic exploratory review of the literature was carried out according to the guidelines of the Joanna Briggs Institute. The information was collected from the PubMed/Medline and Embase databases, using the search strategy “cardiovascular disease” AND “Metalloprotease”. (3) Results: Thirty eight papers that mainly mention 17 types of MMPs were included. Pathologies such as atherosclerosis, coagulation diseases, atrial fibrillation, ischemic heart disease, heart failure, hypertension, dyslipidemias, congenital cyanotic heart disease and Takotsubo cardiomyopathy were identified. (4) Conclusions: The stimulation or inhibition of these biomolecules could generate positive and/or negative effects, which impact the development and prognosis of the disease. Furthermore, they can be potential biomarkers for new diagnostic and even therapeutic approaches in the future. Full article

The occurrence of antibiotic-resistant bacteria is a serious global health issue, and it emphasizes the need for novel antimicrobial agents. This review explores the potential of snake venom as another alternative strategy against antimicrobial resistance. Snake venoms are complex combinations of bioactive peptides and proteins, including metalloproteases (MPs), serine proteases (SPs), phospholipase A₂ (PLA₂) enzymes, three-finger toxins (3FTXs), cysteine-rich secretory proteins (CRISPs), L-amino acid oxidases (LAAOs), and antimicrobial peptides (AMPs). The antibacterial products possess wide-spectrum antibacterial activity against resistant microbes via diverse mechanisms such as cell membrane disruption, enzymatic hydrolysis of microbial structures, generation of oxidative stress, inhibition of biofilms, and immunomodulation. Strong antimicrobial activity is reported by most studies, but these are mostly restricted to in vitro testing with low translational use. Although preliminary insights into molecular targets and physiological effects exist, further studies are needed to clarify long-term safety and therapeutic potential. Special attention is given to snake venom-derived extracellular vesicles (SVEVs), which enhance the therapeutic potential of venom toxins by protecting them from degradation, improving bioavailability, and facilitating targeted delivery. Furthermore, innovative delivery strategies such as PEGylation, liposomes, hydrogels, microneedle patches, biopolymer films, and nanoparticles are discussed for their role in reducing systemic toxicity and enhancing antimicrobial efficacy. The rational modification of venom-derived peptides further expands their therapeutic utility by improving pharmacokinetics and minimizing off-target effects. Together, these approaches highlight the translational potential of snake venom-based therapies as next-generation antimicrobials in the fight against resistant infections. By outlining these challenges and directions, this review positions snake venom as an overlooked but fertile resource in the battle against antibiotic resistance. Full article

ADAMTS-5 (aggrecanase-2) is a major metalloprotease involved in regulating the cartilage extracellular matrix. Due to its role in removing aggrecan in the progression of osteoarthritis (OA), ADAMTS-5 is often regarded as a potential therapeutic target for OA. Punicalagin (PCG), a polyphenolic ellagitannin found in pomegranate (Punica grunatum L.), and ellagic acid (EA), a hydrolytic metabolite of PCG, have been widely investigated as potential disease-modifying osteoarthritis drugs (DMOADs) due to their potent antioxidant and anti-inflammatory properties, but their interaction with ADAMTS-5 has yet to be determined. In this study, molecular docking simulations were used to predict enzyme–inhibitor binding interactions. The results suggest that both compounds may be able to bind within the active site via the formation of H bonds and interactions between the ligand’s aromatic rings and hydrophobic residue in the enzyme with inhibition constants of 183.3 µM and 1.13 µM for PCG and EA, respectively. Biochemical activity against recombinant human ADAMTS-5 was assessed using a dimethylmethylene blue-based assay to determine residual sulfated glycosaminoglycan (sGAG) in porcine articular cartilage. Although its loss could not be attributed to ADAMTS-5, sGAG was effectively persevered by PCG and EA. The potential conversion of PCG to EA by enzyme-catalyzed hydrolysis activity was then investigated using liquid chromatography–mass spectroscopy to determine the potential for the use of PCG and EA as a prodrug–proactive metabolite pair in the development of drug delivery systems to arthritic synovial joints. Full article

Background/Objectives: Tumor cell migration depends on the actin cytoskeleton modified by actin-binding proteins (ABPs). Overexpression of cofilin or thymosin beta4 (Tß4) has been correlated with an increase or decrease in their migratory activity, respectively. Methods: Immunostaining of tumor cells and transfection with EGFP-tagged cofilin or bicistronic vectors leading to independent expression of EGFP and Tß4. Determination of cell migration by transwell or agarose drop assay. Results: We modulated by transfection the intracellular concentrations of cofilin and Tß4 of two colon (3LNLN and EB3) and one breast carcinoma (MDA-MB-231) cell line and analyzed their migratory activity. Increasing wild-type cofilin did not alter their migratory activity, whereas the constitutively active S3A–cofilin mutant elevated migration. Transfection leading to an up- or downregulation of Tß4 showed that MDA-MB-231 and 3LNLN cells responded with a decrease or increase in migration, respectively. Exposure of MDA-MB-231 and 3LNLN cells to increasing concentrations of extracellular Tβ4 (or His-tagged Tß4) induced a biphasic response of migration, being highest around 0.24 µM and decreased at higher extracellular Tß4. Immunostaining of 3LNLN cells exposed to 0.24 µM extracellular His-tagged Tß4 with anti-His antibody indicated its uptake co-localizing with integrin-linked kinase at cell attachment points. Furthermore, the exposure to 0.24 µM His-tagged Tß4 led to increased phosphorylation of AKT1/2 and secretion of matrix metalloproteases. These effects and tumor cell migration were abrogated after exposure of 3LNLN cells to 2.8 µM His-Tß4, also inducing apoptosis in a number of cells. Conclusions: Tumor cell migration can be inhibited by high extracellular Tß4. Full article

Apoptotic executioner caspases-3 and -7 are the main proteases responsible for the execution of apoptosis. Apoptosis is the main form of programmed cell death involved in organism development and maintenance of homeostasis and is commonly impaired in various pathologies. Predominately an immunologically silent form of cell death, it can become immunogenic upon loss of membrane integrity during progression to secondary necrosis, which mostly occurs when apoptotic bodies are not efficiently cleared by efferocytosis. In cancer, the efferocytic capacity can be overwhelmed following chemotherapeutic treatment, thereby providing an opportunity for the potential extracellular functions of executioner apoptotic caspases in the tumor microenvironment. By triggering apoptosis in Jurkat E6.1 acute T cell leukemia cells, we demonstrated that during progression to secondary necrosis, executioner caspases-3 and -7 can be found in the extracellular space. Furthermore, we showed that extracellularly active caspases-3 and -7 can cleave extracellular domains of membrane-bound proteins from MDA-MB-231 breast cancer cells, a function generally executed in the tumor microenvironment by several extracellular proteases from metalloprotease and cathepsin families. As such, this study provides the evidence for the potential involvement of apoptotic caspases-3 and -7 in extracellular proteolytic networks. Presented mass spectrometry data are available via ProteomeXchange with identifier PXD061399. Full article

Although it has been shown that the tumor extracellular matrix (ECM) may sustain the cancer stem cell (CSC) niche, its role in the modulation of CSC properties remains poorly characterized. To elucidate this, paired tumor and adjacent normal mucosa, derived from colon cancer patients’ surgical resections, were decellularized and recellularized with two distinct colon cancer cells, HT-29 or HCT-15. Methods: The matrix impact on cancer stem cell marker expression was evaluated by flow cytometry and qRT-PCR, while transforming growth factor-β (TGF-β) secretion and matrix metalloprotease (MMP) activity were quantified by ELISA and zymography. Results: In contrast to their paired normal counterparts, the tumor decellularized matrices enhanced HT-29 expression of the pluripotency and stemness genes NANOG (p = 0.0117), SOX2 (p = 0.0156), and OCT4 (p = 0.0312) and of the epithelial-to-mesenchymal transition (EMT)-associated transcription factor SNAI1 (p = 0.0156). Notably, no significant differences were found in the expression of SLUG or TGFB on HT-29 or of the six transcripts on HCT-15 cells. HT-29 mRNA alterations were followed by enhanced expression of the stemness-associated receptors cluster of differentiation 44 (CD44), CD133, and CD166 (p = 0.0078), the secretion of TGF-β (p = 0.0286), and MMP-2 (p = 0.0081) and MMP-9 (p = 0.0402) proteolysis. To infer the clinical relevance of these findings, we assessed cohort databases and evidenced that patients expressing higher levels of the four stemness-associated genes (NANOG/SOX2/OCT4/SNAI1) had worse overall survival. This study demonstrates that normal and tumor matrices harbor different stemness potential and suggest patient-derived decellularized matrices as an excellent three-dimensional (3D) model to unveil stemness signatures, appointing candidates for future therapeutic strategies. Full article