Search Results (283)

Background: YES1 is an Src family non-receptor tyrosine-protein kinase that regulates cell growth, migration, survival, and oncogenic signaling. Although YES1 activation mechanisms and substrates have been extensively studied, its phosphosite-specific regulation across diverse biological contexts remains poorly understood. Methods: We performed a large-scale integrative analysis of 3825 publicly available human mass spectrometry-based phosphoproteomic datasets to map YES1 phosphorylation events. Co-modulation, co-occurrence, evolutionary conservation, and disease-association analyses were conducted to characterize the functional and clinical relevance of site-specific YES1 phosphorylation. Results: Y426 emerged as the predominant YES1 phosphosite across diverse biological conditions, localized within the activation loop of the kinase domain and conserved across Src family kinases. Co-modulation analysis identified 421 positively and 102 negatively associated phosphosites enriched in biological processes related to cell cycle regulation, transcription, cytoskeletal remodeling, apoptosis, and carcinogenesis. Among these high-confidence protein phosphosites, we identified 24 binary interactors, 5 upstream regulators, and 8 candidate downstream substrates. Comparison with DisGeNet cancer biomarkers showed overlap between YES1-associated phosphoproteomic signatures and site-specific oncogenic markers across multiple cancers, such as breast cancer, colorectal cancer, leukemia, and lung adenocarcinoma. Conclusions: This study provides a systems-level, phosphosite-focused view of YES1 signaling and supports a central regulatory role for Y426 within global phosphoregulatory and cancer-associated networks. Full article

Heterotopic ossification (HO), the pathological formation of mature bone in non-skeletal soft tissues (e.g., muscles, tendons), severely impairs patient mobility and quality of life. Despite decades of research, systematic analysis of signaling networks across HO subtypes (acquired traumatic HO, hereditary Fibrodysplasia Ossificans Progressiva (FOP), Progressive Osseous Heteroplasia (POH)) remains insufficient, and clinical therapies suffer from high recurrence and severe side effects. This review synthesizes recent advances in HO pathogenesis: FOP involves gain-of-function activin A receptor type I (ACVR1) mutations (mostly R206H), disrupting bone morphogenetic protein (BMP)/Activin A signaling; POH arises from paternal guanine nucleotide-binding protein, alpha-stimulating activity polypeptide (GNAS) loss-of-function mutations, derepressing Hedgehog signaling via reduced cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) activity; tHO features trauma-induced inflammation/hypoxia activating BMP/transforming growth factor–beta (TGF-β) pathways. Key signaling crosstalk (e.g., BMP-Yes-associated protein (YAP)-Indian hedgehog (IHH)) is integrated, and novel therapies (ACVR1 inhibitors, Activin A antibodies, retinoic acid receptor gamma (RARγ) agonists, adeno-associated virus (AAV)-mediated ACVR1 silencing) are highlighted, with emphasis on subtype-specific efficacy. A stratified, mechanism-based HO management framework is proposed, aiming to accelerate precision therapy development and advance understanding of aberrant tissue regeneration. Full article

Background: Glucocorticoids (GCs) are a key pathogenic factor in steroid-induced avascular necrosis of the femoral head (SANFH). GCs can directly damage bone microvascular endothelial cells (BMECs), leading to impaired intraosseous blood supply. Recent studies suggest the Hippo signaling pathway may be involved in the pathogenesis of SANFH; however, its role in vascular endothelial repair and angiogenesis remains unclear. This study aims to investigate the therapeutic effects of human umbilical cord mesenchymal stem cells (hUC-MSCs) on SANFH, with a particular focus on their protective or reparative mechanisms on BMECs. Methods: In vivo, a SANFH mouse model is established and divided into NC, MPS, and hUC-MSCs groups, followed by Micro-CT imagin, hematoxylin and eosin (HE) staining and immunohistochemistry (IHC) (n = 8 per group). In vitro, BMECs are divided into NC, dexamethasone (Dex), hUC-MSCs, and Fer-1 groups to analyze cellular biological behaviors. Target protein expression is assessed using Western blotting and immunofluorescence microscopy. Ferroptosis-related markers are detected via biochemical assays. Mitochondrial ultrastructural changes are observed using transmission electron microscopy. Results: In vivo, the MPS group exhibited significant bone cavitation, sparse trabeculae, and disrupted trabecular architecture in the femoral head. The hUC-MSCs group showed marked improvement in bone microstructure, HE staining showed a significant decrease in the empty lacunae rate in the femoral head, and IHC results revealed markedly increased expression of cluster of differentiation 31 (CD31) and vascular endothelial growth factor (VEGF). In vitro, Dex stimulation suppressed BMECs proliferation. In Dex-treated cells, levels of intracellular reactive oxygen species (ROS), lipid peroxides, ferrous ion (Fe²⁺), malondialdehyde (MDA), acyl-CoA synthetase long chain family member 4 (ACSL4) and nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) were all increased, while expression of glutathione (GSH) and glutathione Peroxidase 4 (GPX4) was reduced. Transmission electron microscopy revealed plasma membrane rupture and reduction or loss of mitochondrial cristae. Furthermore, Dex promoted Hippo-mediated phosphorylation of Yes-associated protein (YAP)/Transcriptional coactivator with PDZ-binding motif (TAZ), upregulated NOX4 expression, and suppressed CD31 and VEGF expression. Following hUC-MSCs treatment, BMECs demonstrated enhanced proliferation, migration, and tube-forming capacity. Cellular GSH and GPX4 levels increased, antioxidant capacity was restored, peroxide accumulation decreased, and cells were protected from ferroptosis-effects comparable to those in the Fer-1 group. Additionally, hUC-MSCs inhibited YAP/TAZ phosphorylation and promoted elevated expression of CD31 and VEGF. Conclusions: These findings suggest that hUC-MSCs may attenuate Dex-induced ferroptosis in BMECs, enhance BMEC migration and angiogenesis, and improve femoral head microstructure in SANFH through modulation of the Hippo-YAP/TAZ signaling pathway. This study provides novel insights into the therapeutic potential of hUC-MSCs for SANFH. Full article

Late relapses are one of the most frustrating aspects of cancer treatment. They are frequently driven by dormant tumor cells and drug-tolerant persisters (DTPs) that survive therapy and later re-enter proliferation. Focal adhesion kinase (FAK) and the mechanosensitive transcriptional co-activators YAP/TAZ integrate extracellular matrix mechanics with intracellular stress signaling to coordinate survival, quiescence and reactivation. We propose that the key determinant is often not “FAK on/off”, but functional mode selection between (Mode I) kinase-dependent signaling bursts linked to adhesion remodeling and regrowth and (Mode II) kinase-independent scaffolding and non-canonical localization (including nuclear pools) that sustain a persistence architecture under stress. This Mode-Switch lens helps explain why ATP-competitive FAK inhibitors can suppress pY397-FAK-dependent outputs yet incompletely eradicate persister reservoirs and motivates strategies that remove FAK protein or disrupt persistence circuitry. We outline operational, pathology-compatible proxies for assigning dominant mode using composite readouts of pY397-FAK/total FAK, FAK localization, and YAP/TAZ/TEAD executor output. Finally, we discuss modality matching—kinase inhibition to suppress regrowth versus FAK degradation and/or YAP/TEAD blockade to dismantle persister reservoirs—as a testable framework for biomarker-stratified intervention in minimal residual disease. Full article

Mesenchymal stem cells (MSCs) sense biophysical cues from their microenvironment, which regulate cytoskeletal organization and the nuclear–cytoplasmic distribution of the mechanotransducer Yes-associated protein (YAP), thereby shaping cellular behavior. Prolonged ex vivo culture on non-physiologically rigid substrates induces persistent nuclear YAP localization, a phenomenon often referred to as mechanical memory. We therefore examined whether transient epigenetic modulation could modulate YAP subcellular localization in human bone marrow-derived MSCs. Treatment with the DNA methyltransferase inhibitor 5-azacitidine (5-Aza) shifted YAP localization toward the cytoplasm in MSCs, without overt changes in pluripotency marker expression or neural differentiation capacity. RNA sequencing revealed broad down-regulation of extracellular matrix (ECM)-related genes following 5-Aza treatment. Independent suppression of ECM production via TGF-β signaling similarly promoted cytoplasmic YAP localization. When subsequently transferred to soft substrates, 5-Aza–treated MSCs restored YAP relocalization despite prior expansion on stiff surfaces. Together, these findings suggest that transient 5-Aza treatment can partially alleviate mechanically induced YAP regulation associated with mechanical memory. Thus, simple and transient administration of 5-Aza may offer a practical means to improve the quality of MSCs during ex vivo expansion for cell-based therapies. Full article

There is no approved drug therapy for schwannomas associated with NF2-related schwannomatosis (NF2-SWN). Neither life-saving surgical resection or radiation are curative and can compound the debilitating neurological effects of the schwannomas. We previously identified fimepinostat, a dual histone deacetylase (HDAC)/phosphoinositide-3 kinase (PI3K) inhibitor, as a promising drug candidate with pro-apoptotic effects on NF2-related schwannomas. This preclinical study used the pharmaceutical formulation of fimepinostat to confirm its efficacy in schwannomas and identify pro-apoptotic signaling pathways. Fimepinostat was tested in human schwannoma model cells, patient-derived primary vestibular and non-vestibular schwannoma cells, and in a sciatic nerve allograft model. The signaling pathways leading to caspase-3-dependent apoptosis were elucidated using immune assays, flow cytometry, imaging, proteome, and acetylome analysis. Acute exposure to fimepinostat led to p21-dependent cell cycle inhibition, upregulation of tumor necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAIL R2), and downregulation of tumor necrosis factor receptor 1 (TNFR1), Yes-associated protein (YAP), and inhibitors of apoptosis. Moreover, fimepinostat downregulated cytokine and chemokine secretion increased by merlin loss in schwannoma cells. Fimepinostat is a promising new drug intervention for NF2-SWN patients with the potential to promote tumor regression. Full article

Cardiac fibrosis represents a final common pathway in a wide range of cardiac disorders, leading to structural remodeling, diastolic dysfunction, and heart failure. From a pathologist’s viewpoint, fibrotic remodeling displays distinctive morphologic patterns such as interstitial, perivascular, and replacement fibrosis, which mirror specific cellular and molecular mechanisms. Central to this process is the activation of cardiac fibroblasts into myofibroblasts, driven by profibrotic signaling cascades such as transforming growth factor beta (TGF-β)/mothers against decapentaplegic homolog proteins (SMAD), Wingless/Integrated signaling pathway (Wnt)/βeta-catenin, and Hippo-Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) pathways. Neurohumoral mediators, including angiotensin II and aldosterone, further amplify extracellular matrix synthesis and tissue stiffness. Epigenetic modulators and non-coding RNAs (n-c RNAs) orchestrate transcriptional programs that perpetuate fibroblast activation. Histopathological correlates of these molecular events, collagen deposition, alpha-smooth muscle actin (α-SMA) expression, and extracellular matrix (ECM) cross-linking, can be demonstrated through immunohistochemistry and digital morphometry. This review integrates molecular signaling and morphologic evidence to delineate the mechanisms of cardiac fibrosis, emphasizing the pathologist’s role as a link between molecular insight and diagnostic interpretation. Understanding these intertwined processes provides the foundation for novel antifibrotic therapies targeting key molecular nodes of fibroblast activation and matrix remodeling. Full article

Ammonium transporters (AMTs) are a class of membrane-associated proteins that play crucial roles in the uptake and transport of ammonium (NH₄⁺ or NH₃). In this study, an ammonium transporter-encoding gene VviAMT4;1 was isolated and identified from table grape ‘Yanpu No.2’. Notably, the expression level of VviAMT4;1 varied significantly across different organs or tissues of ‘Yanpu No.2’, and the highest expression level was detected in the roots of both tissue-cultured seedlings and 5-year-old mature trees. Expression of VviAMT4;1 was significantly up-regulated under NH₄⁺ depletion throughout the whole of tissue-cultured seedlings. Yeast mutant functional complementation indicates that the recombinant strain pYES2-VviAMT4;1/31019b restored growth under different pH conditions. ¹⁵N isotope-labeled uptake kinetics analysis demonstrated that VviAMT4;1 is a typical high-affinity ammonium transporter, with a Kₘ value of 49.58 ± 4.66 μmol·L⁻¹ and a Vₘₐₓ value of 3.29 μmoles·min⁻¹·μg⁻¹ cells. Moreover, VviAMT4;1 can mediate the weak uptake and utilization of methyl amine (MeA⁺) in yeast cells. The VviAMT4;1-mediated NH₄⁺ uptake process may suffer from feedback inhibition by endogenous NH₄⁺ enrichment. This study provides insights into understanding the molecular mechanisms of N transport and utilization in fruit trees. Full article

Kidney fibrosis represents the final common pathway of nearly all progressive renal diseases, linking acute kidney injury (AKI) and chronic kidney disease (CKD) through a maladaptive repair process. Regardless of etiology, persistent inflammation and excessive extracellular matrix (ECM) deposition drive irreversible structural distortion and functional decline in the kidney. Among cellular mediators, macrophages occupy a central role across the continuum from acute injury to fibrosis, orchestrating both tissue injury and repair through dynamic transitions between pro-inflammatory (M1) and pro-fibrotic (M2) states in response to local cues. Here, we synthesize macrophage-driven mechanisms of renal fibrosis, emphasizing recruitment, infiltration, and local proliferation mediated by chemokine–receptor networks and mechanosensitive ion channels. In addition, in this review paper, we provide an overview on the dual roles of macrophages in acute inflammation and chronic remodeling through key cytokine signaling pathways (TLR4/NF-κB, IL-4/STAT6, TGF-β/Smad, IL-10/STAT3), highlighting how metabolic reprogramming, mechanochemical feedback via Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) signaling, and epigenetic modulators collectively stabilize the fibrotic macrophage phenotype. Also, emerging insights into mitochondrial dysfunction, succinate–succinate receptor 1 (SUCNR1) signaling, and autophagy dysregulation reveal the metabolic basis of macrophage persistence in fibrotic kidneys. Understanding these multilayered regulatory circuits offers a framework for therapeutic strategies that selectively target macrophage-dependent fibrogenesis to halt the transition from acute injury to chronic renal failure. Full article

Mechanobiology plays a pivotal role in skeletal development and bone remodeling. Mechanical signals such as matrix stiffness, fluid shear stress, and hydrostatic pressure activate the Runt-related transcription factor 2 (RUNX2) bone-specific transcription factor through pathways including the mitogen-activated protein kinase (MAPK) signaling cascade and yes-associated protein (YAP)/transcriptional co-activator with PDZ-binding motif (TAZ) effectors. RUNX2 itself affects chromatin remodeling and nuclear architecture via Lamin A/C and Nesprin 1, thereby directing osteogenic differentiation. Thus, RUNX2 acts both as a mechanosensor and mechanoregulator, whereas RUNX2’s mechanosensitivity has been leveraged as a target to achieve bone regeneration. Notably, post-translational modifications and epigenetic alterations can orchestrate this regulation, integrating metabolic and circadian signals. However, due to RUNX2’s nuclear localization, its targeting remains a challenging issue. To this end, indirect targeting, through mammalian/mechanistic target of rapamycin complex 1 (mTORC1) or microRNAs (miRNAs), offers new strategies to employ biomechanics in an attempt to intervene with bone diseases driven by mechanical cues or degeneration, and ultimately repair and regenerate the damaged tissues. Herein we critically elaborate upon molecular aspects of RUNX2 regulation towards exploitation at the clinical level. Full article

Objective: This study aims to investigate the functional role of lncRNA STX17-DT, which was previously found to be upregulated in peripheral blood mononuclear cells (PBMCs) of PBC patients, by examining its impact on gene expression and cellular behavior in a human monocyte model. Methods: STX17-DT was overexpressed in THP-1 cells, which was assessed via plasmid transfection. Transcriptomic changes were analyzed by RNA sequencing, followed by comprehensive bioinformatics analyses including differential expression, functional enrichment, transcription factor network, and protein–protein interaction (PPI) analysis. Functional validation was performed using CCK-8 and TUNEL assays to assess proliferation and apoptosis, respectively. Results: Overexpression of STX17-DT led to 1973 differentially expressed genes (DEGs), with 1201 upregulated and 772 downregulated. Key upregulated genes included interferon-stimulated genes (e.g., interferon induced protein 44 like (IFI44L), interferon induced protein 44 (IFI44), guanylate binding protein 1(GBP1)) and chemokines (CCL4, CCL8). Upregulated DEGs were significantly enriched in immune-related pathways such as NF-κB signaling, Toll-like receptor signaling, TNF signaling, and cytokine–cytokine receptor interaction. Downregulated genes were involved in metabolic and signaling pathways such as PI3K–Akt, cAMP, and butanoate metabolism. Transcription factor analysis revealed significant alterations in regulators like Yes1 associated transcriptional regulator(YAP1), nuclear receptor subfamily 4 group A member 1(NR4A1), and MAF bZIP transcription factor B(MAFB). PPI network analysis suggested TNF, TLR4, TLR6, and STAT2 as central hubs. Functionally, STX17-DT overexpression enhanced THP-1 cell proliferation and significantly reduced apoptosis. Conclusions: STX17-DT promoted a pro-inflammatory transcriptomic profile and enhanced monocyte survival in our study, suggesting a potential role in PBC immunopathology. It may represent a potential biomarker and therapeutic target, particularly for patients with advanced disease or suboptimal response to ursodeoxycholic acid. Further studies in primary cells, animal models, and histological samples are warranted to validate its role in PBC pathogenesis. Full article

Background: The Hippo signaling pathway, a highly conserved regulatory cascade, regulates tissue homeostasis, organ size, and tumor suppression. Dysregulation of this pathway contributes to oncogenesis in various human malignancies; however, its clinicopathologic relevance in cervical cancer has not been completely elucidated. Therefore, this study aimed to investigate the expression patterns of key Hippo pathway proteins and analyze their associations with tumor behavior and clinicopathologic features in cervical carcinoma. Materials and Methods: Ninety-nine cervical cancer specimens obtained from hysterectomies performed at Gyeongsang National University Hospital (2012–2019) were retrospectively analyzed. Immunohistochemical staining for Yes-associated protein (YAP), phosphorylated YAP (p-YAP), mammalian sterile-20-like kinase-1 (MST1), and large tumor suppressor kinase-1 (LATS1) was performed on tissue microarrays. Chi-square or Fisher’s exact tests and logistic regression were employed for assessing associations between marker expression and clinicopathologic variables. Functional validation was conducted via small interfering RNA-mediated YAP knockdown in Caski cervical cancer cells, with reverse transcription-polymerase chain reaction, Western blotting, and wound-healing assays assessing YAP suppression and cell migration. Results: YAP and p-YAP were expressed in 71.8% and 62.6% of tumors, respectively; MST1 in 82.8%; and LATS1 in 22.2%. YAP and p-YAP overexpression was correlated with larger tumor size (p = 0.013 and p = 0.011) and higher International Federation of Gynecology and Obstetrics stage (p = 0.007 and p < 0.001). YAP and p-YAP expression was positively correlated (odds ratio, 4.34; 95% confidence interval, 1.70–11.61). MST1 or LATS1 expression demonstrated no significant associations. In vitro, YAP silencing decreased mRNA and protein expression levels and significantly impaired cell migration, supporting its role in tumor aggressiveness. Conclusions: YAP and p-YAP overexpression are associated with advanced stage and larger tumor size in cervical cancer, indicating Hippo pathway dysregulation. YAP functional suppression attenuated migratory capacity, highlighting YAP as a promising prognostic biomarker and therapeutic target. Full article

The deep fascia, traditionally regarded as a passive structural tissue, is now recognized as a metabolically and biologically active structure where biochemical signals and biomechanical forces interact to influence proprioception, pain, force transmission, and adaptation to mechanical load. In this study, the convergence point between Angiotensin II (Ang II) signaling via its receptor, Angiotensin type 1 receptor (AT1R), and the mechanosensor Yes-associated protein (YAP) was investigated in human fascial fibroblasts. The presence of angiotensin II (Ang II) receptors was confirmed in fibroblasts from the deep fascia, with the AT1 receptor being the most prevalent subtype. Short-term exposure to Ang II (15–30 min) caused YAP dephosphorylation and its translocation to the nucleus, indicating YAP activation. Notably, prolonged Ang II treatment (7 days) significantly increased the expression of fibrosis-related genes, including collagen types I and III (COL1A1, COL3A1), and hyaluronan binding protein 2 (HABP2). This gene expression was decreased by pretreatment with the AT1R antagonist irbesartan or the YAP inhibitor verteporfin. Additionally, Ang II promoted fibroblast proliferation/migration, key features of fibrotic progression, through AT1R-dependent pathways. These findings show that Ang II acts as both a biochemical and biomechanical signal in the deep fascia, activating YAP signaling and promoting fibrotic remodeling. Our results uncover a new Ang II–YAP pathway in fascial fibroblasts, offering potential targets for therapy in fibrosis and related conditions involving the deep fascia. Full article

This study investigated the effects of eight weeks of aerobic exercise training on body composition, lipid profiles, organokines (leptin, irisin), inflammatory biomarkers (high-sensitivity C-reactive protein [hs-CRP], interleukin-6 [IL-6]), and intestinal barrier permeability markers (zonulin, lipopolysaccharide-binding protein [LBP]) in overweight and obese women of different age groups. We hypothesized that aerobic exercise would improve cardiorespiratory fitness, body composition, lipid metabolism, and reduce pro-inflammatory responses and intestinal permeability, and that these effects would differ between age groups. A total of 32 participants with a body mass index (BMI) ≥ 23 kg/m² were randomly assigned to one of four groups (n = 8 per group): young exercise (YE), young control (YC), middle-aged exercise (ME), and middle-aged control (MC). The intervention consisted of treadmill running for 50 min per session, four times per week, at an intensity corresponding to 65% of the target heart rate (THR), calculated using the Karvonen formula, for a duration of eight weeks. Body composition variables included body weight, BMI, body fat mass (BFM), percentage body fat (PBF), lean body mass (LBM), and maximal oxygen uptake (VO₂max). Blood samples were analyzed for lipid profiles (total cholesterol [TC], triglycerides [TG], low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C]), organokines, inflammatory markers, and intestinal barrier integrity biomarkers. After the intervention, the YE and ME groups exhibited significant reductions (p < 0.05) in body weight, BMI, BFM, PBF, TC, TG, LDL-C, leptin, hs-CRP, IL-6, zonulin, and LBP. In contrast, LBM and VO₂max significantly increased (p < 0.05) in both exercise groups. No significant changes were observed in irisin concentrations or HDL-C levels (p > 0.05). These results suggest that aerobic exercise training, irrespective of age, is effective in improving cardiorespiratory fitness, body composition, and lipid metabolism, while simultaneously reducing systemic inflammation and is associated with favorable changes in circulating biomarkers of intestinal barrier function in overweight and obese women. Full article

Innate immunity is the body’s first line of defense for mounting robust antiviral signaling. However, the role of cytoskeletal prestress, a hallmark of cellular mechanotransduction, in regulating innate immune pathways such as retinoic acid-inducible gene I (RIG-I) signaling remains poorly understood. Herein, we show that cells on soft vs. rigid substrates elicit cytoskeletal prestress-dependent activation of RIG-I signaling, leading to differential type-I interferon (IFN) gene expression. Cells were cultured on soft (0.6 kPa) and stiff (8.5 kPa) substrates to modulate cellular traction and prestress, followed by transfection of Poly(I:C), a synthetic viral dsRNA mimic, to measure the RIG-I-mediated innate immune response. Cells on soft substrates show minimal activation of RIG-I signaling, resulting in low expression of IFN-β1 and other IFN-stimulated genes (ISGs), compared to cells on stiff substrates. We further demonstrate that activation of TANK Binding Kinase 1 (TBK1), a downstream effector of the RIG-I pathway, is inhibited in cells on soft substrates due to the cytoplasmic sequestration of the Yes-associated protein (YAP), a HIPPO pathway effector protein. In contrast, cells on stiffer substrates experienced decreased TBK1 inhibition due to the nuclear localization of YAP and exhibited elevated TBK1 activation and heightened IFN and ISG expressions. Together, we demonstrate that cytoskeletal prestress represents a key biophysical regulator of innate immune signaling. Full article