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International Journal of Molecular... Jun 2024Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest of human malignancies and carries an exceptionally poor prognosis. It is mostly driven by multiple...
Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest of human malignancies and carries an exceptionally poor prognosis. It is mostly driven by multiple oncogenic alterations, with the highest mutation frequency being observed in the KRAS gene, which is a key oncogenic driver of tumorogenesis and malignant progression in PDAC. However, KRAS remained undruggable for decades until the emergence of G12C mutation specific KRAS inhibitors. Despite this development, this therapeutic approach to target KRAS directly is not routinely used for PDAC patients, with the reasons being the rare presence of G12C mutation in PDAC with only 1-2% of occurring cases, modest therapeutic efficacy, activation of compensatory pathways leading to cell resistance, and absence of effective KRASG12D or pan-KRAS inhibitors. Additionally, indirect approaches to targeting KRAS through upstream and downstream regulators or effectors were also found to be either ineffective or known to cause major toxicities. For this reason, new and more effective treatment strategies that combine different therapeutic modalities aiming at achieving synergism and minimizing intrinsic or adaptive resistance mechanisms are required. In the current work presented here, pancreatic cancer cell lines with oncogenic KRAS G12C, G12D, or wild-type KRAS were treated with specific KRAS or SOS1/2 inhibitors, and therapeutic synergisms with concomitant MEK inhibition and irradiation were systematically evaluated by means of cell viability, 2D-clonogenic, 3D-anchorage independent soft agar, and bioluminescent ATP assays. Underlying pathophysiological mechanisms were examined by using Western blot analyses, apoptosis assay, and RAS activation assay.
Topics: Humans; Pancreatic Neoplasms; Proto-Oncogene Proteins p21(ras); Cell Line, Tumor; Protein Kinase Inhibitors; Carcinoma, Pancreatic Ductal; Signal Transduction; Apoptosis; Mutation; Cell Proliferation; Mitogen-Activated Protein Kinase Kinases
PubMed: 38892436
DOI: 10.3390/ijms25116249 -
International Journal of Molecular... Jun 2024Reactive oxygen species (ROS) are central to inter- and intracellular signaling. Their localized and transient effects are due to their short half-life, especially when... (Review)
Review
Reactive oxygen species (ROS) are central to inter- and intracellular signaling. Their localized and transient effects are due to their short half-life, especially when generated in controlled amounts. Upon T cell receptor (TCR) activation, regulated ROS signaling is primarily initiated by complexes I and III of the electron transport chain (ETC). Subsequent ROS production triggers the activation of nicotinamide adenine dinucleotide phosphate oxidase 2 (NADPH oxidase 2), prolonging the oxidative signal. This signal then engages kinase signaling cascades such as the mitogen-activated protein kinase (MAPK) pathway and increases the activity of REDOX-sensitive transcription factors such as nuclear factor-kappa B (NF-κB) and activator protein-1 (AP-1). To limit ROS overproduction and prevent oxidative stress, nuclear factor erythroid 2-related factor 2 (Nrf2) and antioxidant proteins such as superoxide dismutases (SODs) finely regulate signal intensity and are capable of terminating the oxidative signal when needed. Thus, oxidative signals, such as T cell activation, are well-controlled and critical for cellular communication.
Topics: Reactive Oxygen Species; Humans; T-Lymphocytes; Signal Transduction; Animals; Lymphocyte Activation; Oxidative Stress; Oxidation-Reduction; Receptors, Antigen, T-Cell; NF-E2-Related Factor 2
PubMed: 38892300
DOI: 10.3390/ijms25116114 -
International Journal of Molecular... May 2024N-acetylcysteine (NAC) is a mucolytic agent with antioxidant and anti-inflammatory properties. The respiratory syncytial virus (RSV) is one of the most important... (Review)
Review
N-acetylcysteine (NAC) is a mucolytic agent with antioxidant and anti-inflammatory properties. The respiratory syncytial virus (RSV) is one of the most important etiological factors of lower respiratory tract infections, and exposure to air pollution appears to be additionally associated with higher RSV incidence and disease severity. We aimed to systematically review the existing literature to determine which molecular mechanisms mediate the effects of NAC in an RSV infection and air pollution, and to identify the knowledge gaps in this field. A search for original studies was carried out in three databases and a calibrated extraction grid was used to extract data on the NAC treatment (dose, timing), the air pollutant type, and the most significant mechanisms. We identified only 28 studies conducted in human cellular models ( = 18), animal models ( = 7), and mixed models ( = 3). NAC treatment improves the barrier function of the epithelium damaged by RSV and air pollution, and reduces the epithelial permeability, protecting against viral entry. NAC may also block RSV-activated phosphorylation of the epidermal growth factor receptor (EGFR), which promotes endocytosis and facilitates cell entry. EGFR also enhances the release of a mucin gene, MUC5AC, which increases mucus viscosity and causes goblet cell metaplasia; the effects are abrogated by NAC. NAC blocks virus release from the infected cells, attenuates the cigarette smoke-induced shift from necrosis to apoptosis, and reverses the block in IFN-γ-induced antiviral gene expression caused by the inhibited Stat1 phosphorylation. Increased synthesis of pro-inflammatory cytokines and chemokines is induced by both RSV and air pollutants and is mediated by the nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways that are activated in response to oxidative stress. MCP-1 (monocyte chemoattractant protein-1) and RANTES (regulated upon activation, expressed and secreted by normal T cells) partially mediate airway hyperresponsiveness (AHR), and therapeutic (but not preventive) NAC administration reduces the inflammatory response and has been shown to reduce ozone-induced AHR. Oxidative stress-induced DNA damage and cellular senescence, observed during RSV infection and exposure to air pollution, can be partially reversed by NAC administration, while data on the emphysema formation are disputed. The review identified potential common molecular mechanisms of interest that are affected by NAC and may alleviate both the RSV infection and the effects of air pollution. Data are limited and gaps in knowledge include the optimal timing or dosage of NAC administration, therefore future studies should clarify these uncertainties and verify its practical use.
Topics: Humans; Acetylcysteine; Respiratory Syncytial Virus Infections; Animals; Air Pollution; ErbB Receptors
PubMed: 38892239
DOI: 10.3390/ijms25116051 -
International Journal of Molecular... May 2024Understanding the factors which control endothelial cell (EC) function and angiogenesis is crucial for developing the horse as a disease model, but equine ECs remain...
Understanding the factors which control endothelial cell (EC) function and angiogenesis is crucial for developing the horse as a disease model, but equine ECs remain poorly studied. In this study, we have optimised methods for the isolation and culture of equine aortic endothelial cells (EAoECs) and characterised their angiogenic functions in vitro. Mechanical dissociation, followed by magnetic purification using an anti-VE-cadherin antibody, resulted in EC-enriched cultures suitable for further study. Fibroblast growth factor 2 (FGF2) increased the EAoEC proliferation rate and stimulated scratch wound closure and tube formation by EAoECs on the extracellular matrix. Pharmacological inhibitors of FGF receptor 1 (FGFR1) (SU5402) or mitogen-activated protein kinase (MEK) (PD184352) blocked FGF2-induced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and functional responses, suggesting that these are dependent on FGFR1/MEK-ERK signalling. In marked contrast, vascular endothelial growth factor-A (VEGF-A) had no effect on EAoEC proliferation, migration, or tubulogenesis and did not promote ERK1/2 phosphorylation, indicating a lack of sensitivity to this classical pro-angiogenic growth factor. Gene expression analysis showed that unlike human ECs, FGFR1 is expressed by EAoECs at a much higher level than both VEGF receptor (VEGFR)1 and VEGFR2. These results suggest a predominant role for FGF2 versus VEGF-A in controlling the angiogenic functions of equine ECs. Collectively, our novel data provide a sound basis for studying angiogenic processes in horses and lay the foundations for comparative studies of EC biology in horses versus humans.
Topics: Animals; Fibroblast Growth Factor 2; Horses; Endothelial Cells; Neovascularization, Physiologic; Vascular Endothelial Growth Factor A; Cell Proliferation; Receptor, Fibroblast Growth Factor, Type 1; Cell Movement; Cells, Cultured; MAP Kinase Signaling System; Phosphorylation
PubMed: 38892205
DOI: 10.3390/ijms25116017 -
International Journal of Molecular... May 2024Pertuzumab (Perjeta), a humanized antibody binding to the dimerization arm of HER2 (Human epidermal growth factor receptor-2), has failed as a monotherapy agent in HER2...
Pertuzumab (Perjeta), a humanized antibody binding to the dimerization arm of HER2 (Human epidermal growth factor receptor-2), has failed as a monotherapy agent in HER2 overexpressing malignancies. Since the molecular interaction of HER2 with ligand-bound EGFR (epidermal growth factor receptor) has been implied in mitogenic signaling and malignant proliferation, we hypothesized that this interaction, rather than HER2 expression and oligomerization alone, could be a potential molecular target and predictor of the efficacy of pertuzumab treatment. Therefore, we investigated static and dynamic interactions between HER2 and EGFR molecules upon EGF stimulus in the presence and absence of pertuzumab in HER2+ EGFR+ SK-BR-3 breast tumor cells using Förster resonance energy transfer (FRET) microscopy and fluorescence correlation and cross-correlation spectroscopy (FCS/FCCS). The consequential activation of signaling and changes in cell proliferation were measured by Western blotting and MTT assay. The autocorrelation functions of HER2 diffusion were best fitted by a three-component model corrected for triplet formation, and among these components the slowly diffusing membrane component revealed aggregation induced by EGFR ligand binding, as evidenced by photon-counting histograms and co-diffusing fractions. This aggregation has efficiently been prevented by pertuzumab treatment, which also inhibited the post-stimulus interaction of EGFR and HER2, as monitored by changes in FRET efficiency. Overall, the data demonstrated that pertuzumab, by hindering post-stimulus interaction between EGFR and HER2, inhibits EGFR-evoked HER2 aggregation and phosphorylation and leads to a dose-dependent decrease in cell proliferation, particularly when higher amounts of EGF are present. Consequently, we propose that EGFR expression on HER2-positive tumors could be taken into consideration as a potential biomarker when predicting the outcome of pertuzumab treatment.
Topics: Humans; Antibodies, Monoclonal, Humanized; ErbB Receptors; Receptor, ErbB-2; Cell Line, Tumor; Signal Transduction; Female; Cell Proliferation; Breast Neoplasms; Fluorescence Resonance Energy Transfer; Transcriptional Activation; Antineoplastic Agents, Immunological
PubMed: 38892166
DOI: 10.3390/ijms25115978 -
International Journal of Molecular... May 2024Ginsenosides, bioactive compounds from the genus , have potential therapeutic effects on diverse ailments, including diabetes. Emerging evidence suggests their... (Review)
Review
Ginsenosides, bioactive compounds from the genus , have potential therapeutic effects on diverse ailments, including diabetes. Emerging evidence suggests their involvement in bone metabolism. The present review summarizes the current understanding of the effects of ginsenosides on osteoporosis, periodontal disease, and osteoarthritis. Their mechanisms of action include effects on osteoblasts, osteoclasts, periodontal ligament fibroblasts (PDLFs), and chondrocytes, which are pivotal in maintaining bone, periodontal tissue, and cartilage homeostasis. Ginsenosides may exert their beneficial effects by enhancing PDLF and osteoblast activity, suppressing osteoclast function, augmenting chondrocyte synthesis in the cartilage matrix, and mitigating connective tissue degradation. Moreover, they possess antioxidant, anti-inflammatory, antimicrobial, and anti-pyroptotic properties. Their efficacy in increasing bone density, ameliorating periodontitis, and alleviating osteoarthritis symptoms has been demonstrated in preclinical studies using animal models. In terms of their mechanism of action, ginsenosides modulate cellular differentiation, activity, and key signaling pathway molecules, such as mitogen-activated protein kinases (MAPKs), while also regulating various mediators. Furthermore, the symptomatic relief observed in animal models lends further credence to their therapeutic utility. However, to translate these preclinical findings into clinical practice, rigorous animal and clinical investigations are imperative to ascertain the safety, efficacy, and optimal dosing regimens in human subjects.
Topics: Ginsenosides; Humans; Osteoarthritis; Animals; Osteoporosis; Periodontal Diseases; Bone and Bones
PubMed: 38892015
DOI: 10.3390/ijms25115828 -
International Journal of Molecular... May 2024Modular supramolecular complexes, where different proteins are assembled to gather targeting capability and photofunctional properties within the same structures, are of...
Modular supramolecular complexes, where different proteins are assembled to gather targeting capability and photofunctional properties within the same structures, are of special interest for bacterial photodynamic inactivation, given their inherent biocompatibility and flexibility. We have recently proposed one such structure, exploiting the tetrameric bacterial protein streptavidin as the main building block, to target protein A. To expand the palette of targets, we have linked biotinylated Concanavalin A, a sugar-binding protein, to a methylene blue-labelled streptavidin. By applying a combination of spectroscopy and microscopy, we demonstrate the binding of Concanavalin A to the walls of Gram-positive and Gram-negative . Photoinactivation is observed for both bacterial strains in the low micromolar range, although the moderate affinity for the molecular targets and the low singlet oxygen yields limit the overall efficiency. Finally, we apply a maximum entropy method to the analysis of autocorrelation traces, which proves particularly useful when interpreting signals measured for diffusing systems heterogeneous in size, such as fluorescent species bound to bacteria.
Topics: Concanavalin A; Escherichia coli; Staphylococcus aureus; Cell Wall; Streptavidin; Bacterial Proteins; Protein Binding
PubMed: 38891937
DOI: 10.3390/ijms25115751 -
International Journal of Molecular... May 2024Alzheimer's disease (AD) is characterized by the deposition in the brain of senile plaques composed of amyloid-β peptides (Aβs) that increase inflammation. An...
Reduction in Hippocampal Amyloid-β Peptide (Aβ) Content during Glycine-Proline-Glutamate (Gly-Pro-Glu) Co-Administration Is Associated with Changes in Inflammation and Insulin-like Growth Factor (IGF)-I Signaling.
Alzheimer's disease (AD) is characterized by the deposition in the brain of senile plaques composed of amyloid-β peptides (Aβs) that increase inflammation. An endogenous peptide derived from the insulin-like growth factor (IGF)-I, glycine-proline-glutamate (GPE), has IGF-I-sensitizing and neuroprotective actions. Here, we examined the effects of GPE on Aβ levels and hippocampal inflammation generated by the intracerebroventricular infusion of Aβ25-35 for 2 weeks (300 pmol/day) in ovariectomized rats and the signaling-related pathways and levels of Aβ-degrading enzymes associated with these GPE-related effects. GPE prevented the Aβ-induced increase in the phosphorylation of p38 mitogen-activated protein kinase and the reduction in activation of signal transducer and activator of transcription 3, insulin receptor substrate-1, and Akt, as well as on interleukin (IL)-2 and IL-13 levels in the hippocampus. The functionality of somatostatin, measured as the percentage of inhibition of adenylate cyclase activity and the levels of insulin-degrading enzyme, was also preserved by GPE co-treatment. These findings indicate that GPE co-administration may protect from Aβ insult by changing hippocampal cytokine content and somatostatin functionality through regulation of leptin- and IGF-I-signaling pathways that could influence the reduction in Aβ levels through modulation of levels and/or activity of Aβ proteases.
Topics: Animals; Amyloid beta-Peptides; Hippocampus; Rats; Insulin-Like Growth Factor I; Signal Transduction; Female; Oligopeptides; Inflammation; Peptide Fragments; Rats, Wistar; Alzheimer Disease; p38 Mitogen-Activated Protein Kinases; Proto-Oncogene Proteins c-akt; Insulin-Like Peptides
PubMed: 38891902
DOI: 10.3390/ijms25115716 -
CNS Neuroscience & Therapeutics Jun 2024Spinal cord injury (SCI) represents a complex pathology within the central nervous system (CNS), leading to severe sensory and motor impairments. It activates various... (Review)
Review
Spinal cord injury (SCI) represents a complex pathology within the central nervous system (CNS), leading to severe sensory and motor impairments. It activates various signaling pathways, notably the mitogen-activated protein kinase (MAPK) pathway. Present treatment approaches primarily focus on symptomatic relief, lacking efficacy in addressing the underlying pathophysiological mechanisms. Emerging research underscores the significance of the MAPK pathway in neuronal differentiation, growth, survival, axonal regeneration, and inflammatory responses post-SCI. Modulating this pathway post-injury has shown promise in attenuating inflammation, minimizing apoptosis, alleviating neuropathic pain, and fostering neural regeneration. Given its pivotal role, the MAPK pathway emerges as a potential therapeutic target in SCI management. This review synthesizes current knowledge on SCI pathology, delineates the MAPK pathway's characteristics, and explores its dual roles in SCI pathology and therapeutic interventions. Furthermore, it addresses the existing challenges in MAPK research in the context of SCI, proposing solutions to overcome these hurdles. Our aim is to offer a comprehensive reference for future research on the MAPK pathway and SCI, laying the groundwork for targeted therapeutic strategies.
Topics: Spinal Cord Injuries; Humans; Animals; MAP Kinase Signaling System; Mitogen-Activated Protein Kinases
PubMed: 38887853
DOI: 10.1111/cns.14807 -
MedComm Jul 2024Coffee, a widely consumed beverage, has shown benefits for human health but lacks sufficient basic and clinical evidence to fully understand its impacts and mechanisms....
Coffee, a widely consumed beverage, has shown benefits for human health but lacks sufficient basic and clinical evidence to fully understand its impacts and mechanisms. Here, we conducted a cross-sectional observational study of coffee consumption and a 1-month clinical trial in humans. We found that coffee consumption significantly reshaped the immune system and metabolism, including reduced levels of inflammatory factors and a reduced frequency of senescent T cells. The frequency of senescent T cells and the levels of the senescence-associated secretory phenotype were lower in both long-term coffee consumers and new coffee consumers than in coffee nondrinking subjects, suggesting that coffee has anti-immunosenescence effects. Moreover, coffee consumption downregulated the activities of the The Janus kinase/signal transduction and activator of transcription (JAK/STAT) and mitogen-activated protein kinases (MAPK) signaling pathways and reduced systemic proinflammatory cytokine levels. Mechanistically, coffee-associated metabolites, such as 1-methylxanthine, 3-methylxanthine, paraxanthine, and ceramide, reduced the frequency of senescent CD4CD57T cells in vitro. Finally, in vivo, coffee intake alleviated inflammation and immunosenescence in imiquimod-induced psoriasis-like mice. Our results provide novel evidence of the anti-inflammatory and anti-immunosenescence effects of coffee, suggesting that coffee consumption could be considered a healthy habit.
PubMed: 38887468
DOI: 10.1002/mco2.617