Search Results (1,340)

Cellular senescence, a state of stable cell cycle arrest accompanied by a complex senescence-associated secretory phenotype (SASP), is a fundamental biological process implicated as a key driver of lung aging and lung age-related diseases (LARDs). This review provides a comprehensive overview of the rapidly evolving field of senotyping based on cellular heterogeneity in lung development and aging in health and disease. It also delves into the molecular mechanisms driving senescence and SASP production, highlighting pathways such as p53/p21, p16^INK4a/RB, mTOR, and p38 MAPK as therapeutic targets. The involvement of various novel SASP proteins, such as GDP15, cytokines/chemokines, growth factors, and DNA damage response proteins. We further highlight the effectiveness of senotherapeutics in mitigating the detrimental effects of senescent cell (SnC) accumulation within the lungs. It also outlines two main therapeutic approaches: senolytics, which selectively trigger apoptosis in SnCs, and senomorphics (also known as senostatics), which mitigate the detrimental effects of the SASP without necessarily removing the senescent cells. Various classes of senolytic and senomorphic drugs are currently in clinical trials including natural products (e.g., quercetin, fisetin, resveratrol) and repurposed drugs (e.g., dasatinib, navitoclax, metformin, rapamycin) that has demonstrated therapeutic promise in improving tissue function, alleviating LARDs, and extending health span. We discuss the future of these strategies in lung research and further elaborate upon the usability of novel approaches including HSP90 inhibitors, senolytic CAR-T cells, Antibody drug conjugate and galactose-modified prodrugs in influencing the field of personalized medicine in future. Overall, this comprehensive review highlights the progress made so far and the challenges faced in the field of cellular senescence including SnC heterogeneity, states of senescence, senotyping, immunosenescence, drug delivery, target specificity, long-term safety, and the need for robust cell-based biomarkers. Future perspectives, such as advanced delivery systems, and combination therapies, are considered critical for translating the potential of senotherapeutics into effective clinical applications for age-related pulmonary diseases/conditions. Full article

Human cryptosporidiosis caused by the zoonotic apicomplexan parasite Cryptosporidium parvum represents a neglected and re-emerging poverty-related disease. C. parvum possesses minimalistic metabolic capacities and highly depends on its intestinal epithelial host cell for intracellular replication. Based on previous results showing that glycolysis and glutaminolysis inhibition diminished C. parvum replication in vitro, we here investigated the impact of the olive oil component oleocanthal on C. parvum infection in HCT-8 cells under physioxia (5% O₂) and hyperoxia (21% O₂). Oleocanthal targets a broad spectrum of regulatory molecules, amongst which mTOR represents a master regulator of glycolysis and glutaminolysis. Using a host cell pre-treatment as well as a pre- and post-infection treatment protocol, 5 µM oleocanthal reduced C. parvum infection rates between 51% and 94%. Host cellular metabolic conversion rates linked oleocanthal-induced inhibition of C. parvum infection with an impairment in glutaminolysis, representing an important metabolic pathway in intestinal cells. The principal involvement of mTOR in C. parvum inhibition was confirmed by another mTOR-inhibitor (PP242, 0.5 µM), which also reduced C. parvum infection by 70–77%. Given that oleocanthal is not a selective mTOR inhibitor, we assume that this compound drives a multi-target-based inhibition of asexual C. parvum replication, amongst which mTOR is addressed. Full article

Extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitors show therapeutic potential in triple-negative breast cancer (TNBC), but resistance through compensatory signaling limits their efficacy. We previously identified the secretory carrier membrane protein 3 (SCAMP3) as a regulator of TNBC progression and ERK1/2 activation. Here, we investigated the role of SCAMP3 in ERK1/2 signaling and therapeutic response using TMT-based LC-MS/MS phosphoproteomics of wild-type (WT) and SCAMP3 knockout (SC3KO) SUM-149 cells under basal conditions, after epidermal growth factor (EGF) stimulation, and during ERK1/2 inhibition with MK-8353. A total of 4408 phosphosites were quantified, with 1093 significantly changed. SC3KO abolished residual ERK activity under MK-8353 and affected the compensatory activation of oncogenic pathways observed in WT cells. SC3KO reduced the phosphorylation of ERK feedback regulators RAF proto-oncogene serine/threonine-protein kinase Raf-1 (S43) and the dual-specificity mitogen-activated protein kinase kinase 2 (MEK2) (T394), affected other ERK targets, including nucleoporins, transcription factors, and metabolic enzymes triosephosphate isomerase (TPI1) (S21) and ATP-citrate lyase (ACLY) (S455). SCAMP3 loss also impaired the mammalian target of rapamycin complex I (mTORC1) signaling and disrupted autophagic flux, evidenced by elevated sequestosome-1 (SQSTM1/p62) and microtubule-associated protein light chain 3 (LC3B-II) with reduced levels of the autophagosome lysosome maturation marker, Rab7A. Beyond ERK substrates, SC3KO affected phosphorylation events mediated by other kinases. These findings position SCAMP3 as a central coordinator of ERK signaling and autophagy. Our results support SCAMP3 as a potential therapeutic target to enhance ERK1/2 inhibitor clinical efficacy and overcome adaptive resistance mechanisms in TNBC. Full article

Background: B7-H3, an immunoregulatory protein of the B7 family, has been associated with both anti-cancer immunity and tumor promotion, with its expression commonly correlated with poor prognosis. Although it is frequently expressed across cancers, its heterogeneity may limit the effectiveness of B7-H3-targeted therapies. Consequently, a sensitive and non-invasive method is needed to assess B7-H3 expression for patient selection and stratification. Single-domain antibody fragments (sdAbs) offer a promising platform for developing such a diagnostic tool. Methods: To generate B7-H3 sdAbs, two Ilamas were immunized with the recombinant human B7-H3 protein. Positive clones were selected through Phage biopanning and characterized for thermal stability, binding specificity, and affinity to human and murine B7-H3 proteins. Selected sdAbs were radiolabeled with Technetium-99m (^99mTc) and evaluated for B7-H3 detection in two xenograft tumor models using micro-SPECT/CT imaging and dissection studies. Results: Sixteen purified sdAbs bound specifically to recombinant B7-H3 proteins and cells expressing native B7-H3 antigens, with nanomolar affinities. The four best-performing sdAbs bound promiscuously to tested mouse and human B7-H3 isoforms. Lead sdAb C51 labeled with ^99mTc displayed specific accumulation across two human B7-H3⁺ tumor models, achieving high contrast with a tumor-to-blood ratio of up to 10 ± 3.16, and a tumor uptake of up to 4.96 ± 1.4%IA/g at 1.5 h post injection. Conclusions: The lead sdAb enabled rapid, specific, and non-invasive imaging of human B7-H3⁺ tumors. Its isoform promiscuity supports broad applicability across cancers expressing different human B7-H3 isoforms. These results support further development for clinical translation to enable patient selection and improved B7-H3-targeted therapies. Full article

Reactive oxygen species (ROS) function as critical signaling molecules in cancer biology, promoting proliferation, angiogenesis, and metastasis at controlled levels while inducing lethal damage when exceeding the cell’s buffering capacity. To survive under this state of chronic oxidative stress, cancer cells become dependent on a hyperactive antioxidant shield, primarily orchestrated by the Nrf2, glutathione (GSH), and thioredoxin (Trx) systems. These defenses maintain redox homeostasis and sustain oncogenic signaling, notably through the oxidative inactivation of tumor-suppressor phosphatases, such as PTEN, which drives the PI3K/AKT/mTOR pathway. Targeting this addiction to a rewired redox state has emerged as a compelling therapeutic strategy. Pro-oxidant therapies aim to overwhelm cellular defenses, with agents like high-dose vitamin C and arsenic trioxide (ATO) showing significant tumor-selective toxicity. Inhibiting the master regulator Nrf2 with compounds such as Brusatol or ML385 disrupts the core antioxidant response. Disruption of the GSH system by inhibiting cysteine uptake with sulfasalazine or erastin potently induces ferroptosis, a non-apoptotic cell death driven by lipid peroxidation. Furthermore, the thioredoxin system is targeted by the repurposed drug auranofin, which irreversibly inhibits thioredoxin reductase (TrxR). Extensive preclinical data and ongoing clinical trials support the concept that this reliance on redox adaptation is a cancer-selective vulnerability. Moreover, novel therapeutic strategies, including the expanding field of redox-active metal complexes, such as manganese porphyrins, which strategically leverage the differential redox state of normal versus cancer cells through both pro-oxidant and indirect Nrf2-mediated antioxidative mechanisms (triggered by Keap1 oxidation), with several agents currently in advanced clinical trials, have also been discussed. Essentially, pharmacologically tipping the redox balance beyond the threshold of tolerance offers a rational and powerful approach to eliminate malignant cells, defining a novel frontier for targeted cancer therapy. Full article

Anxiety disorders are closely associated with oxidative stress-mediated neuronal damage, mitochondrial dysfunction, and apoptosis. In this study, we investigated the neuroprotective effects of Lactiplantibacillus plantarum HY7715 in a mouse model of restraint stress-induced anxiety, and in neuronal cell models (HT-22 mouse hippocampal neuroblast cell and SH-SY5Y human neuroblastoma cells). Oral administration of HY7715 (1 × 10⁹ CFU/kg/day) alleviated anxiety-like behaviors significantly, as shown by increased central exploration in the open field test and prolonged open-arm activity in the elevated plus maze. HY7715 reduced serum norepinephrine levels elevated by stress, and restored hippocampal expression of brain-derived neurotrophic factor, while suppressing pro-inflammatory (NF-κB, IL-6) and pro-apoptotic (BAX, caspase-3) markers. It also increased expression of mitochondrial regulatory genes (SIRT1, mTOR), and decreased that of cytochrome c, in brain tissue. Histological analysis revealed that HY7715 preserved neuronal integrity in the CA1 and CA3 hippocampal regions. In vitro, HY7715 attenuated oxidative stress-induced cytotoxicity, decreased intracellular ROS accumulation, maintained mitochondrial activity, and inhibited apoptosis of both neuronal cell types, showing greater efficacy than the strain type L. plantarum KCTC3108. These findings suggest that HY7715 exerts neuroprotective effects by modulating oxidative stress/apoptosis/mitochondrial pathways, and highlight its potential as a psychobiotic for stress-related neuropsychiatric disorders. Full article

Background: Despite advances in gene-targeted and immunotherapies, many aggressive cancers—including glioblastoma and triple-negative breast cancer—remain refractory to treatment. Mounting evidence implicates metabolic reprogramming, especially dysregulation of glucose and glutamine metabolism, as a core hallmark of tumor progression. Natural compounds with metabolic-modulatory effects have emerged as promising adjuncts in oncology. Research Question and Objectives: This review investigates the following question: How can metabolic-targeted therapies—particularly those modulating the Warburg effect and glutamine metabolism—improve cancer treatment outcomes, and what role do natural compounds play in this strategy? The objectives were to (1) evaluate the therapeutic potential of metabolic interventions targeting glucose and glutamine metabolism, (2) assess natural compounds with metabolic regulatory activity, (3) examine integration of metabolic-targeted therapies with conventional treatments, and (4) identify metabolic vulnerabilities in resistant malignancies. Methods: A qualitative systematic review (QualSR) was conducted following PRISMA guidelines. A total of 87 peer-reviewed studies published between 2000 and 2024 were included. Inclusion criteria required clearly defined mechanistic or clinical endpoints and, for clinical trials, sample sizes ≥ 30. Data extraction focused on tumor response, survival, metabolic modulation, and safety profiles. Results: Curcumin significantly reduced serum TNF-α and IL-6 (both p = 0.001) and improved antioxidant capacity (p = 0.001). EGCG downregulated ERα (p = 0.002) and upregulated tumor suppressors p53 and p21 (p = 0.001, p = 0.02). High-dose intravenous vitamin C combined with chemoradiotherapy yielded a 44.4% pathologic complete response rate in rectal cancer. Berberine suppressed Akt/mTOR signaling and glutamine transporter SLC1A5 across tumor types (q < 10⁻¹⁰). However, poor bioavailability (e.g., EGCG t½ = 3.4 ± 0.3 h) and systemic toxicity limit their standalone clinical application. Conclusions: Metabolic-targeted therapies—particularly natural compounds acting on glucose and glutamine pathways—offer a viable adjunct to standard cancer therapies. Clinical translation will require biomarker-driven patient stratification, improved delivery systems, and combination trials to optimize the therapeutic impact in treatment-resistant cancers. Full article

Cellular redox pathways are critical regulators of various biological processes, including the intricate modulation of intracellular signaling pathways. This review explores how major redox enzymes—such as catalase, superoxide dismutases, glutathione peroxidases, thioredoxins, and peroxiredoxins—interact with key cellular signaling pathways, including receptor tyrosine kinase, mTORC1/AMPK, Wnt/β-catenin, TGF-β/SMAD, NF-κB, Hedgehog, Notch, and GPCR signaling. By investigating mechanisms such as ROS-mediated activation, cysteine oxidation, spatial enzyme localization, and phosphatase regulation, we demonstrate the extensive influence of redox balance on cellular signaling dynamics. Understanding these redox-dependent interactions provides insights into pathophysiological conditions ranging from cancer to fibrosis, offering novel therapeutic opportunities. Full article

The aim of this study was to investigate the clinical and prognostic significance of the NOTCH1 pathway in oral squamous cell carcinoma (OSCC). To this end, the expression of NOTCH1 and two downstream targets, HES1 and p21, was evaluated by immunohistochemistry in 165 OSCC patient specimens. Clinicopathological associations and impact on survival were assessed. Possible mechanistic crosstalk with epithelial–mesenchymal transition (EMT) induction through combined E-cadherin and Vimentin markers, or mTORC1 activation by means of phospho-S6 expression were also investigated. NOTCH1 staining was detected in 56 (35%) tumors, nuclear HES1 in 131 (81%) and nuclear p21 in 116 (70%) tumors. p21 was strongly correlated with mTORC1 activation and HES1 expression was inversely associated with EMT status. NOTCH1 expression was positively associated with an advanced T stage, neck lymph node metastasis, advanced TNM stage, second primary cancer, and was significantly associated with shorter disease-specific survival (DSS). By contrast, HES1 and p21 expression showed significant associations with early clinical stages, and combined p21 and pS6 expression (p21+/p-S6+) distinguished good-prognosis patients. Multivariate Cox analysis further revealed NOTCH1 expression as a significant independent predictor of poor DSS. Mechanistically, we found a strong link between p21 and pS6 proteins, which could potentially serve as a good-prognosis classifier for OSCC patients. Full article

Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver tumor. Due to its aggressive nature and resistance to conventional treatments, there is a pressing need to develop novel and more effective therapies for this deadly malignancy. Here, we explored the therapeutic potential of the DNA minor groove binders trabectedin (TRB) and lurbinectedin (LUR) for the treatment of iCCA using cell lines, spheroids, cancer-associated fibroblasts (CAFs), patient-derived tumor organoids (PDOs), and the chicken chorioallantoic membrane (CAM) in vivo model. TRB and, more substantially, LUR, significantly inhibited cell growth in iCCA cell lines, spheroids, CAFs, and PDOs at very low nanomolar concentrations. Specifically, the two drugs significantly reduced proliferation, triggered apoptosis, and caused DNA damage in iCCA cells. At the metabolic level, TRB and LUR decreased mitochondrial respiration and glycolysis. At the molecular level, the two compounds effectively downregulated the mammalian target of rapamycin complex 1 (mTORC1) and Hippo/YAP pathways and suppressed the expression of yes-associated protein 1 (YAP1), cellular myelocytomatosis oncogene (c-Myc), E2F transcription factor 1 (E2F1), Bromodomain-containing protein 4 (BRD4), TEA domain transcription factor 4 (TEAD4), and cluster of differentiation 7 (CD7) proto-oncogenes. Furthermore, LUR significantly restrained the in vivo growth of iCCA cells in the CAM model. Our data indicate that TRB and LUR possess strong anti-proliferative and pro-apoptotic activities and could represent promising therapeutic agents for the treatment of iCCA. Full article

Background: Arginine (Arg) is thought to potentially stimulate protein synthesis. Although the detailed mechanism by which Arg regulates protein synthesis is not fully known, it is believed to occur primarily through the mechanistic target of rapamycin complex 1 (mTORC1)-dependent activation of translation initiation. The aim of this study was to evaluate the ability of Arg to stimulate translation initiation to upregulate protein synthesis and identify the possible signaling pathways involved in the stimulatory effect of Arg on mRNA translation in skeletal muscle. Methods: Overnight-fasted mice were intraperitoneally injected with Arg, sacrificed 1 h later, and then the gastrocnemius muscles were excised. In addition, to determine the mechanism by which Arg stimulates translation initiation in skeletal muscle, we used mouse-derived C2C12 myotubes. Cells were preincubated with several inhibitors of intracellular signaling or the G protein–coupled receptor, Class C, group 6, subtype A (GPRC6A) antagonist, and then added to the culture with Arg. Phosphorylation of 4E-binding protein 1 (4E-BP1) and ribosomal protein S6 kinase (S6K1) as markers of mTORC1-dependent protein synthesis activity was measured. Results: Intraperitoneal injection of Arg increased 4E-BP1 and S6K1 phosphorylation. In C2C12 myotubes, Arg addition significantly increased the phosphorylation of 4E-BP1 and S6K1, and this upregulation was attenuated by pretreatment with the mTORC1 inhibitor rapamycin. In addition, pretreatment with the PI3K inhibitor LY294002, the AKT inhibitor MK-2206, and the GPRC6A antagonist calindol completely inhibited Arg-upregulated 4E-BP1 and S6K1 phosphorylation. Conclusions: The findings of this study suggest that Arg stimulates the initiation of mRNA translation via the GPRC6A/PI3K/AKT/mTORC1 signaling pathway, thereby stimulating protein synthesis in skeletal muscle. Full article

Angiogenesis, the formation of new blood vessels from pre-existing vasculature, is essential for physiological processes such as development and wound healing, but its dysregulation contributes to a range of pathological conditions including cancer, diabetic retinopathy, and chronic inflammation. In recent years, marine-derived compounds have emerged as promising multitarget agents with anti-angiogenic potential. Posidonia oceanica, a Mediterranean seagrass traditionally used in folk medicine, is increasingly recognized for its pharmacological properties, including antioxidant, anti-inflammatory, and anti-invasive activities. This study investigated the effects of a hydroethanolic extract from P. oceanica leaves (POE) on human Endothelial Colony-Forming Cells (ECFCs), a subpopulation of endothelial progenitor cells with high proliferative and vessel-forming capacity, and a relevant model for studying pathological angiogenesis. ECFCs were treated with POE (4–8 µg/mL), and cell viability, morphology, migration, invasion, tube formation, oxidative stress, and activation markers were evaluated. POE did not alter ECFC morphology or viability, as confirmed by Trypan Blue and MTT assays. However, functional assays revealed that POE significantly impaired ECFC migration, invasion, and in vitro angiogenesis in a dose-dependent manner. Under VEGF (Vascular endothelial growth factor) stimulation, POE reduced intracellular ROS accumulation and downregulated key redox-regulating genes (hTRX1, hTRX2, PRDX2, AKR1C1, AKR1B10). Western blot analysis showed that POE inhibited VEGF-induced phosphorylation of KDR, mTOR and p-ERK, while p-AKT remained elevated, indicating selective disruption of VEGF downstream signaling. Furthermore, POE reduced the expression of pro-inflammatory and pro-coagulant markers (VCAM-1, ICAM-1, TF) and partially reversed TNF-α–induced endothelial activation. These findings suggest that POE exerts anti-angiogenic effects through a multitargeted mechanism, supporting its potential as a natural therapeutic agent for diseases characterized by aberrant angiogenesis. Full article

Eukaryotes use diverse nutrient acquisition strategies, including autotrophy, heterotrophy, mixotrophy, and symbiosis, which shape the evolution of cell regulatory networks. The Target of Rapamycin (TOR) kinase is a conserved growth regulator that in most species functions within two complexes, TORC1 and TORC2. TORC1 is broadly conserved and uniquely sensitive to rapamycin, whereas the evolutionary distribution of TORC2 is less well-defined. We built a sensitive hidden Markov model (HMM)-based pipeline to survey core TORC1 and TORC2 components across more than 800 sequenced eukaryotic genomes spanning multiple major supergroups. Both complexes are present in early-branching lineages, consistent with their presence in the last eukaryotic common ancestor, followed by multiple lineage-specific losses of TORC2 and, more rarely, TORC1. A striking pattern emerges in which TORC2 is uniformly absent from photosynthetic autotrophs derived from primary endosymbiosis and frequently lost in those derived from secondary or tertiary events. In contrast, TORC2 is consistently retained in mixotrophs, which obtain carbon from both photosynthesis and environmental uptake, and in free-living obligate heterotrophs. These findings suggest that TORC2 supports heterotrophic metabolism and is often dispensable under strict autotrophy. Our results provide a framework for the evolutionary divergence of TOR signaling and highlight metabolic and ecological pressures that shape TOR complex retention across eukaryotes. Full article

The mammalian target of rapamycin pathway, mTOR, is a crucial signaling pathway that regulates cell growth, proliferation, metabolism, and survival. Due to its dysregulation it is involved in several ailments such as cancer or age-related diseases. The discovery of mTOR and the understanding of its biological functions were greatly facilitated by the use of rapamycin, an antibiotic of natural origin, which allosterically inhibits mTORC1, effectively blocking its function. In this entirely computational study, we investigated mTOR’s interaction with seven ligands: two clinically established inhibitors (everolimus and rapamycin) and five lignin-derived oligomers, a renewable natural polyphenol recently used for the drug delivery of everolimus. The seven complexes were analyzed through all-atom molecular dynamics simulations in explicit solvent using a high-performance computing platform. Trajectory analyses revealed stable interactions between mTOR and all ligands, with lignin-derived compounds showing comparable or enhanced binding stability relative to reference drugs. To evaluate the stability of the molecular complex and the behavior of the ligand over time, we analyzed key parameters including root mean square deviation, root mean square fluctuation, number of hydrogen bonds, binding free energy, and conformational dynamics assessed through principal component analysis. Our results suggest that lignin fragments are a promising, sustainable scaffold for developing novel mTOR inhibitors. Full article

MYCN amplification without concurrent RB1 mutations characterizes a rare yet highly aggressive subtype of retinoblastoma; however, its precise developmental origins and therapeutic vulnerabilities remain incompletely understood. Here, we modeled this subtype by lentiviral-mediated MYCN overexpression in human pluripotent stem cell-derived retinal organoids, revealing a discrete developmental window (days 70–120) during which retinal progenitors showed heightened susceptibility to transformation. Tumors arising in this period exhibited robust proliferation, expressed SOX2, and lacked CRX, consistent with origin from primitive retinal progenitors. MYCN-overexpressing organoids generated stable cell lines that reproducibly gave rise to MYCN-driven tumors when xenografted into immunodeficient mice. Transcriptomic profiling demonstrated that MYCN-overexpressing organoids closely recapitulated molecular features of patient-derived MYCN-amplified retinoblastomas, particularly through activation of MYC/E2F and mTORC1 signaling pathways. Pharmacological screening further identified distinct therapeutic vulnerabilities, demonstrating distinct subtype-specific sensitivity of MYCN-driven cells to transcriptional inhibitors (THZ1, Flavopiridol) and the cell-cycle inhibitor Volasertib, indicative of a unique oncogene-addicted state compared to RB1-deficient retinoblastoma cells. Collectively, our study elucidates the developmental and molecular mechanisms underpinning MYCN-driven retinoblastoma, establishes a robust and clinically relevant human retinal organoid platform, and highlights targeted transcriptional inhibition as a promising therapeutic approach for this aggressive pediatric cancer subtype. Full article