Search Results (751)

Glioblastoma multiforme (GBM) remains one of the most aggressive and treatment-resistant brain tumors, with poor prognosis and limited therapeutic options. Background/Objectives: Integrin α_vβ₃, a cell surface receptor overexpressed in GBM, specifically binds to cyclic arginine-glycine-aspartate-D-phenylalanine-lysine (c(RGDfK)) motif, making it a valuable target for tumor-specific delivery and PET imaging. This study explores a novel radiotheranostic agent, [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK), which combines the imaging and therapeutic capabilities of copper-64 (⁶⁴Cu) and the cytotoxic activity of a terpyridine-platinum (TP) complex, conjugated to c(RGDfK). Methods: A robust protocol was developed for the small-scale preparation of NOTA-TP-c(RGDfK). Comparative cellular studies were conducted using U87 MG glioblastoma (GBM) cells and SVG p12 human astrocytes to evaluate the performance of [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK) relative to [⁶⁴Cu]Cu-NOTA-c(RGDfK), [⁶⁴Cu]Cu-NOTA-TP, ^natCu-NOTA-TP-c(RGDfK), cisplatin, and temozolomide. Results: ⁶⁴Cu-radiolabeling of NOTA-TP-c(RGDfK) was achieved with >99% radiochemical purity, and competition assays confirmed high binding affinity to integrin α_vβ₃ (IC₅₀ = 16 ± 8 nM). Cellular uptake, internalization, and retention studies demonstrated significantly higher accumulation of [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK) in U87 MG cells compared to control compounds, with 38.8 ± 1.8% uptake and 28.0 ± 1.0% internalization at 24 h. Nuclear localization (6.0 ± 0.5%) and stable intracellular retention further support its therapeutic potential for inducing localized DNA damage. Importantly, [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK) exhibited the highest cytotoxicity in U87 MG cells (IC₅₀ = 10 ± 2 nM at 48 h), while maintaining minimal toxicity in normal SVG p12 astrocytes. Conclusions: These results highlight [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK) as a promising targeted radiotheranostic agent for GBM, warranting further preclinical development Full article

A thermosensitive collagen-based gel (TSV gel), containing type I and III collagen, has been developed to improve the handling and stability of bone graft materials. However, its direct effect on osteoblasts is not well understood. This in vitro study evaluated the biological response of human oral osteoblasts to four bone substitutes: OsteoBiol^® GTO^® (larger granules with 20% TSV gel), Gen-OS^® (smaller granules), Gen-OS^® combined with 50% TSV gel (Gen-OS^®+TSV), and TSV gel alone. Cell proliferation, adhesion, morphology, collagen and calcium deposition, alkaline phosphatase (ALP) activity, gene expression of osteogenic markers and integrins, and changes in pH and extracellular calcium and phosphate levels were investigated. All materials supported osteoblast activity, but Gen-OS+TSV and GTO showed the most pronounced effects. These two groups promoted better cell adhesion and proliferation, higher ALP activity, and greater matrix mineralization. GTO improved cell adhesion, while the addition of TSV gel to Gen-OS enhanced biological responses compared with Gen-OS alone. Integrins α2, α5, β1, and β3, important for cell attachment to collagen, were notably upregulated in Gen-OS+TSV and GTO. Both groups also showed increased expression of osteogenic markers such as BMP-2, ALP, and osteocalcin (OCN). Higher extracellular ion concentrations and a more alkaline pH were observed, particularly in conditions without cells, suggesting active ion uptake by osteoblasts. In conclusion, combining TSV gel with collagen-based granules improves the cellular environment for osteoblast activity and may support bone regeneration more effectively than using either component alone. Full article

Cardiomyocyte hypertrophy is regulated by several factors, including the ADP-ribosylation factor (Arf) family of small G proteins, among others. For instance, ArfGAP with dual pleckstrin homology domains 1 (Adap1) exerts an anti-hypertrophic effect in cultured cardiomyocytes. Its homologous protein, Adap2, is also expressed in the heart but its role remains elusive. To elucidate its function, we investigated the effects of adenoviral-mediated overexpression of Adap2 in cultured neonatal rat ventricular myocytes under both basal and pro-hypertrophic conditions, employing a range of microscopy and biochemical techniques. Despite minimal detection in neonatal rat hearts, Adap2 was found to be well expressed in adult rat hearts, being predominantly localized at the membrane fraction. In contrast to Adap1, overexpression of Adap2 provokes the robust accumulation of β1-integrin at the cellular surface of cultured cardiomyocytes. Interestingly, overexpressed Adap2 relocalizes at the sarcolemma and increases the size of cardiomyocytes upon phenylephrine stimulation, despite attenuating Erk1/2 phosphorylation and Nppa gene expression. Under these same conditions, cardiomyocytes overexpressing Adap2 also express higher level of detyrosinated tubulin, a marker of hypertrophic response. These findings provide new insights into the pro-hypertrophic function of Adap2 in cardiomyocytes. Full article

Skeletal muscle development is a critical economic trait in livestock, governed by myogenic satellite cell regulation. Integrins mediate mechanical anchorage to the ECM and enable ECM–intracellular signaling. CIB2, as an EF-hand-domain protein involved in mechanotransduction, shows significant developmental regulation in goat muscle. Although the role of CIB2 in skeletal muscle growth is poorly characterized, we observed pronounced developmental upregulation of IB2 in postnatal goat muscle. CIB2 expression increased >20-fold by postnatal day 90 (P90) compared to P1, sustaining elevation through P180 (p < 0.05). Functional investigations indicated that siRNA-mediated knockdown of CIB2 could inhibit myoblast proliferation by inducing S-phase arrest (p < 0.05) and downregulating the expression of CDK4/Cyclin D/E. Simultaneously, CIB2 interference treatment was found to decrease the proliferative activity of goat myogenic satellite cells, yet it significantly promoted differentiation by upregulating the expression of MyoD/MyoG/MyHC (p < 0.01). Mechanistically, CTCF was identified as a transcriptional repressor binding to an intragenic region of the CIB2 gene locus (ChIP enrichment: 2.3-fold, p < 0.05). Knockdown of CTCF induced upregulation of CIB2 (p < 0.05). RNA-seq analysis established CIB2 as a calcium signaling hub: its interference activated IL-17/TNF and complement cascades, while overexpression suppressed focal adhesion/ECM–receptor interactions and enriched neuroendocrine pathways. Collectively, this study identifies the CTCF-CIB2–integrin α7β1–PI3K/AKT axis as a novel molecular mechanism that regulates the balance of myogenic fate in goats. These findings offer promising targets for genomic selection and precision breeding strategies aimed at enhancing muscle productivity in ruminants. Full article

Osteoarthritis (OA) is a chronic progressive joint disease characterized by cartilage degradation, subchondral bone remodeling, and synovial inflammation. This complex disorder arises from the interplay between mechanical stress and inflammatory processes, which is mediated by interconnected molecular signaling pathways. This review explores the dual roles of inflammatory and mechanical signaling in OA pathogenesis, focusing on crucial pathways such as NF-kB, JAK/STAT, and MAPK in inflammation, as well as Wnt/β-catenin, Integrin-FAK, and Hippo-YAP/TAZ in mechanotransduction. The interplay between these pathways highlights a vicious cycle wherein mechanical stress exacerbates inflammation, and inflammation weakens cartilage, increasing its vulnerability to mechanical damage. Additionally, we discuss emerging therapeutic strategies targeting these pathways, including inhibitors of cartilage-degrading enzymes, anti-inflammatory biologics, cell-based regenerative approaches, and non-pharmacological mechanical interventions. By dissecting the molecular mechanisms underlying OA, this review aims to provide insights into novel interventions that address both inflammatory and mechanical components of the disease, paving the way for precision medicine in OA management. Full article

Collagen type I (COL(I)) is a key component of the extracellular matrix (ECM) and is involved in cell signaling and migration through cell receptors. Collagen degradation produces bioactive peptides (matrikines), which influence cellular processes. In this study, we investigated the biological effects of nine most abundant, naturally occurring urinary COL(I)-derived peptides on human endothelial cells at physiological concentrations, using cell migration assays, mass spectrometry-based proteomics, flow cytometry, and AlphaFold 3. While none of the peptides significantly altered endothelial migration by themselves at physiological concentrations, full-length COL(I) increased cell migration, which was inhibited by Peptide 1 (²²⁹NGDDGEAGKPGRPGERGPpGp²⁴⁹). This peptide uniquely contains the DGEA and GRPGER motifs, interacting with integrin α2β1. Flow cytometry confirmed the presence of integrin α2β1 on human endothelial cells, and AlphaFold 3 modeling predicted an interaction between Peptide 1 and integrin α2. Mass spectrometry-based proteomics investigating signaling pathways revealed that COL(I) triggered phosphorylation events linked to integrin α2β1 activation and cell migration, which were absent in COL(I) plus peptide 1-treated cells. These findings identify Peptide 1 as a biologically active COL(I)-derived peptide at a physiological concentration capable of modulating collagen-induced cell migration, and provide a foundation for further investigation into its mechanisms of action and role in urine excretion. Full article

Bone is the most frequent site of distant metastasis in advanced prostate cancer (PCa), contributing substantially to patient morbidity and mortality. Hypoxia, a defining feature of the solid tumour microenvironment, plays a pivotal role in driving bone-tropic progression by promoting epithelial-to-mesenchymal transition (EMT), cancer stemness, extracellular matrix (ECM) remodelling, and activation of key signalling pathways such as Wingless/Integrated (Wnt) Wnt/β-catenin and PI3K/Akt. Hypoxia also enhances the secretion of extracellular vesicles (EVs), enriched with pro-metastatic cargos, and upregulates bone-homing molecules including CXCR4, integrins, and PIM kinases, fostering pre-metastatic niche formation and skeletal colonisation. In this review, we analysed current evidence on how hypoxia orchestrates PCa dissemination to bone, focusing on the molecular crosstalk between HIF signalling, Wnt activation, EV-mediated communication, and cellular plasticity. We further explore therapeutic strategies targeting hypoxia-related pathways, such as HIF inhibitors, hypoxia-activated prodrugs, and Wnt antagonists, with an emphasis on overcoming therapy resistance in castration-resistant PCa (CRPC). By examining the mechanistic underpinnings of hypoxia-driven bone metastasis, we highlight promising translational avenues for improving patient outcomes in advanced PCa. Full article

Skin aging is characterized by compromised epidermal homeostasis and dermo-epidermal junction (DEJ) integrity, resulting in reduced stem cell potential and impaired tissue regeneration. This study investigated the effects of Andrographis paniculata extract (APE) on keratinocyte stem cells (KSCs) and DEJ composition in human skin. Using human skin explants and cell culture models, we demonstrated that APE treatment enhances DEJ composition by increasing Collagen IV and Laminin production while decreasing MMP-9 expression, without altering epidermal structure or differentiation. In the same model, APE preserved stemness potential by upregulating markers related to niche components (collagen XVII and β1-integrin), proliferation (Ki-67 and KRT15), and stem cell capacity (Survivin and LRIG1). In vitro studies revealed that APE selectively stimulated KSC proliferation without affecting transit amplifying cells and promoted Collagen IV and Laminin secretion, particularly in KSCs. Furthermore, in a co-culture model simulating a compromised DEJ (UVB-induced), APE increased Laminin production in KSCs, suggesting a protective effect against photo-damage. These findings indicate that APE enhances DEJ composition and preserves stem cell potential, highlighting its promise as a candidate for skin anti-aging strategies targeting stem cell maintenance and extracellular matrix stability to promote skin regeneration and repair. Full article

Inherited epidermolysis bullosa (EB) is a heterogeneous clinical entity that includes over 30 phenotypically and/or genotypically distinct inherited disorders, characterized by mechanical skin fragility and bullae formation. Junctional EB (JEB) is an autosomal recessive disease characterized by an intermediated cleavage level within the skin layers, commonly at the “lamina lucida”. Laryngo-onycho-cutaneous syndrome (LOC) is an extremely rare variant of JEB, characterized by granulation tissue formation in specific body sites (skin, larynx, and nails). Although most cases of JEB are caused by pathogenic variants occurring in the genes encoding for classical components of the lamina lucida, such as laminin 332 (LAMA3, LAMB3, LAMC2), integrin α6β4 (ITGA6, ITGB4), and collagen XVII (COL17A1), other variants have also been described. We report the case of a 4-month-old male infant who presented with recurrent bullous and erosive lesions from the first month of life. At the first dermatological evaluation, the patient was agitated and exhibited hoarse breathing, a clinical sign suggestive of laryngeal involvement. Multiple polygonal skin erosions were observed on the cheeks, along with similar isolated, roundish lesions on the scalp and legs. Notably, nail dystrophy and near-complete anonychia were evident on the left first and fifth toes. Due to the coexistence of skin erosions and nail dystrophy in such a young infant, a congenital bullous disorder was suspected, prompting molecular analysis of all potentially involved genes. In the patient’s DNA, clinical exome sequencing (CES) identified a pathogenic variant, apparently in homozygosity, in the exon 1 of the LAMA3 gene (18q11.2; NM_000227.6): c.47G > A;p.Trp16*. The presence of this variant was confirmed, in heterozygosity, in the genomic DNA of the patient’s mother, while it was absent in the father’s DNA. Subsequently, trio-based SNP array analysis was performed, revealing a paternally derived pathogenic microdeletion encompassing the LAMA3 locus (18q11.2). To our knowledge, this is the first reported case of JEB with a LOC-like phenotype caused by a maternally inherited monoallelic nonsense mutation in LAMA3, unmasked by an almost complete deletion of the paternal allele. The combined use of exome sequencing and SNP array is proving essential for elucidating autosomal recessive diseases with a discordant segregation. This is pivotal for providing accurate genetic counseling to parents regarding future pregnancies. Full article

Background and aim: ANGPTL3 is a hepatokine acting as a negative regulator of lipoprotein lipase (LPL) through its N-terminal domain. Besides this activity, the C-terminal domain of ANGPTL3 interacts with integrin αVβ3. Since integrins are involved in inflammation and in the initiation of atherosclerotic plaque, the aim of our study was to evaluate the potential direct pro-inflammatory action of ANGPTL3 through the interaction of the fibrinogen-like domain and integrin αVβ3. Methods: We utilized cultured THP-1 human-derived macrophages and evaluated their pro-inflammatory phenotype in response to treatment with human recombinant ANGPTL3 (hANGPTL3). By Western blot, RT-qPCR, biochemical analysis, and ELISA assays, we determined the expression of genes and proteins involved in lipid metabolism and inflammatory response as well as intracellular cholesterol and triglyceride levels. In addition, we evaluated the effect of hANGPTL3 on the cellular cholesterol efflux process. Results: Incubation of THP-1-derived macrophages with 100 ng/mL of hANGPTL3 increased the mRNA expression of the pro-inflammatory cytokines IL-1β, IL-6, and TNFα (respectively, 1.87 ± 0.08-fold, 1.35 ± 0.11-fold, and 2.49 ± 0.43-fold vs. control). The secretion of TNFα, determined by an ELISA assay, was also induced by hANGPTL3 (1.98 ± 0.4-fold vs. control). The pro-inflammatory effect of hANGPTL3 was partially counteracted by co-treatment with the integrin αVβ3 inhibitor RGD peptide, reducing the mRNA levels of IL-1β (3.35 ± 0.35-fold vs. 2.54 ± 0.25-fold for hANGPTL3 vs. hANGPTL3 + RGD, respectively). Moreover, hANGPTL3 reduced cholesterol efflux to apoA-I, with a parallel increase in the intracellular triglyceride and cholesterol contents by 31.2 ± 2.8% and 20.0 ± 4.1%, respectively, compared to the control. Conclusions: ANGPTL3 is an important liver-derived regulator of plasma lipoprotein metabolism, and overall, our results add a new important pro-inflammatory activity of this circulating protein. This new function of ANGPTL3 could also be related to triglyceride and cholesterol accumulation into macrophages. Full article

Cobalt is an essential trace element involved in key biological processes. It serves most notably as a component of vitamin B₁₂ (cobalamin) and a regulator of erythropoiesis. While cobalt deficiency can lead to disorders such as megaloblastic anemia, excess cobalt poses toxicological risks to the thyroid, cardiovascular, and hematopoietic systems. In recent years, cobalt ions (Co²⁺) have gained attention for their ability to mimic hypoxia and promote angiogenesis. This represents a crucial mechanism for tissue regeneration. Cobalt mediates this effect mainly by stabilizing hypoxia-inducible factor 1α (HIF-1α) under normoxic conditions, thereby upregulating angiogenic genes, including VEGF, FGF, and EPO. Experimental studies—from cell culture to animal models—have demonstrated cobalt-induced enhancement of endothelial proliferation, migration, and microvascular formation. Emerging evidence also indicates that Co²⁺-stimulated macrophages secrete integrin-β1-rich exosomes. These exosomes enhance endothelial motility and tubulogenesis independently of VEGF. Furthermore, cobalt-modified biomaterials have been developed to deliver cobalt ions in a controlled manner. Examples include cobalt-doped β-tricalcium phosphate or bioactive glasses. These materials support both angiogenesis and osteogenesis.This review summarizes current findings on cobalt’s role in angiogenesis. The emphasis is on its potential in cobalt-based biomaterials for tissue engineering and regenerative medicine. Full article

Fibrotic disorders pose a significant global health burden due to limited treatment options, creating an urgent need for novel therapeutic strategies. Amphiregulin (AREG), a low-affinity ligand for the epidermal growth factor receptor (EGFR), has emerged as a key mediator of fibrogenesis through dual signaling pathways. Unlike high-affinity EGFR ligands, AREG induces sustained signaling that activates downstream effectors and promotes the integrin-mediated activation of transforming growth factor (TGF)-β. This enables both canonical and non-canonical EGFR signaling pathways that contribute to fibrosis. Elevated AREG expression correlates with disease severity across multiple organs, including the lungs, kidneys, liver, and heart. The therapeutic targeting of AREG has shown promising antifibrotic and anticancer effects, suggesting a dual-benefit strategy. The increasing recognition of the shared mechanisms between fibrosis and cancer further supports the development of unified treatment approaches. The inhibition of AREG has been shown to sensitize fibrotic tumor microenvironments to chemotherapy, enhancing combination therapy efficacy. Targeted therapies, such as Self-Assembled-Micelle inhibitory RNA (SAMiRNA)-AREG, have demonstrated enhanced specificity and favorable safety profiles in preclinical studies and early clinical trials. Personalized treatment based on AREG expression may improve clinical outcomes, establishing AREG as a promising precision medicine target for both fibrotic and malignant diseases. This review aims to provide a comprehensive understanding of AREG biology and evaluate its therapeutic potential in fibrosis and cancer. Full article

Background: Increased IL-1β levels may promote carcinogenesis and metastasis by affecting tumor biology and the tumor microenvironment (TME). In this context, extracellular vesicles (EVs) play a key role in cell-to-cell communication, thus modulating the TME and immune response. Here, we aimed to test whether tumor-derived small EVs (TEVs) isolated from sensitive and osimertinib-resistant (OR) non-small-cell lung cancer (NSCLC) cells may promote EMT via fibronectin binding to α5β1 integrin as well as suppress the immune system and if these effects may be favored by IL-1β. Methods: TEVs were isolated from control, OR, and IL-1β-stimulated NSCLC cells. Expressions of fibronectin and PD-L1 were screened in TEVs and the mRNA levels of vimentin and SMAD3 were also assessed in cancer cells after TEV co-culturing. Furthermore, to detect the effect on immune cells, we co-cultured TEVs with lung cancer patients’ peripheral blood mononuclear cells (PBMCs). Results: TEVs were positive for fibronectin and the highest protein levels were found in TEVs obtained from the OR and IL-1β-stimulated cells. TEV-mediated activation of α5β1 signaling led to the upregulation of vimentin and SMAD3 mRNA in NSCLC cells and stimulated cell migration. EVs also increased PD-1, CTLA-4, FOXP3, TNF-α, IL-12, and INF-γ mRNA in lung cancer patients’ immune cells. Conclusions: Our findings indicate that TEVs promote EMT in NSCLC cells by the activation of the fibronectin–α5β1 axis. Finally, IL-1β stimulation induces TEV release with biological properties similar to OR TEVs, thus leading to cancer invasion and immune suppression and suggesting that inflammation can promote tumor spreading. Full article

The attachment of the oral epithelium to the abutment surface is crucial for the long-term success of dental implants. This study aimed to evaluate the attachment of human epithelial cells to anodized titanium surfaces. Anodized titanium discs were used as the experimental group, while machined titanium discs served as the control. Surface roughness and wettability were first measured for each group. Next, human epithelial cells were seeded onto each disc at a density of 4.0 × 10⁴ cells/cm² and evaluated 3, 6, and 24 h later for cell proliferation, as well as mRNA expression and protein levels of laminin and integrin β₄. Surface roughness was comparable between the two groups; however, wettability was significantly higher in the experimental group. Cell proliferation increased over time in both groups and showed no significant difference. Notably, the expression levels of both laminin and integrin β₄ were significantly higher in the experimental group at 24 h. Furthermore, protein localization of laminin and integrin β₄ was observed along the cell margins on the anodized surface. These findings suggest that anodization enhances epithelial cell attachment by promoting the expression and peripheral organization of key adhesion molecules. Full article

The junctional epithelium, which lines the inner gingival surface, seals the gingival sulcus to block the infiltration of food debris and pathogens. The junctional epithelium is derived from the reduced enamel epithelium, consisting of late developmental stage ameloblasts and accessory cells. No prior studies have investigated whether defective ameloblast differentiation or enamel matrix formation affects junctional epithelium anatomy or function. Here, we examined the junctional epithelium in mice exhibiting amelogenesis imperfecta due to loss-of-function mutations in the major enamel matrix protein amelogenin (Amelx^−/−) or the critical enamel matrix protease KLK4 (Klk4^−/−). Histological analyses demonstrated altered morphology and cell layer thickness of the junctional epithelium in Amelx^−/− and Klk4^−/− mice as compared to wt. Immunohistochemistry revealed reduced ODAM, laminin 5, and integrin α6, all of which are critical for the adhesion of the junctional epithelium to the enamel in Amelx^−/− and Klk4^−/− mice. Furthermore, we observed altered cell–cell adhesion and increased permeability of Dextran-GFP through the mutants’ junctional epithelium, indicating defective barrier function. Reduced β-catenin and Ki67 at the base of the junctional epithelium in mutants suggest impaired mitotic activity and reduced capacity to replenish continuously desquamated epithelium. These findings highlight the essential role of normal amelogenesis in maintaining junctional epithelium homeostasis. Full article