Search Results (123)

Background: Dysregulated G protein-coupled receptor (GPCR) signaling is increasingly implicated as an important driver for oncogenesis. Uveal melanoma (UM) represents a highly metastatic intraocular malignancy primarily driven by activating mutations in G protein family members Gαq/11. Although Tebentafusp, the first FDA-approved bi-specific T-cell engager for UM, improves survival, its activity is restricted to specific human leukocyte antigen (HLA) alleles, highlighting the need to identify broadly expressed targetable proteins for immunotherapeutic strategies. Here we aimed to define surfaceome and phospho-signaling signatures associated with oncogenic Gαq-signaling. Methods: Heterologous and UM in vitro systems were used to interrogate Gαq-driven changes. HEK293T cells were transfected with wild-type Gαq or the oncogenic Gαq (R183Q) mutant, with surface marker profiles quantified by flow cytometry. Complementary immunophenotyping was performed in the Gαq-mutant UM cell line MP46 and Gα11-mutant line MP41. Kinase phosphorylation was assessed in control and Gαq mutant conditions followed by effect size estimation (Hedges’ g), Welch’s t-test, principal component analysis, and Spearman correlation-based network analysis of surface and phosphoprotein readouts. Results: Hyperactive Gαq in HEK293T cells induced graded remodeling of surface protein profiles, including reduced CD56 (NCAM) and CD49c (ITGA3) expression. Similarly, in UM models, MP46 versus MP41 had limited expression of CD56 and CD49c. Moreover, phospho kinase profiling and network analysis identified altered surface-phosphoprotein relationships, including a CD56-p70 S6 kinase association. Conclusions: These data provide new insights into Gαq-driven modulators of UM phenotype of relevance for studies of tumor–microenvironment interaction and metastasis. Full article

Listeria monocytogenes (Lm) is an important zoonotic foodborne pathogen that causes severe rhombencephalitis in ruminants. The trigeminal ganglion is a critical node for Lm invasion of the central nervous system via neural pathways. However, the roles of key virulence factors InlA, InlB, and LLO from ovine-derived Lm in trigeminal ganglion neuron infection remain unclear. In this study, LM90SB2, an ovine-derived Lm strain isolated from a sheep with encephalitis in Xinjiang, China, was used as the wild type, and its ΔInlAB double-gene deletion and ΔInlABO triple-gene deletion mutants were constructed. Primary mouse trigeminal ganglion cells (TGCs) were infected with these strains, and cell-association and invasion assays, bacterial colonization analysis, cell scratch tests, Western blotting, and qRT-PCR were performed to explore the effects of InlA, InlB, and LLO on Lm infection of TGCs and their regulatory roles in host adhesion molecules N-cadherin and NCAM1. The results showed that the wild-type LM90SB2 had significantly stronger cell-association, invasion, and colonization abilities in TGCs than the ΔInlAB and ΔInlABO mutants (p < 0.01 or p < 0.0001). LM90SB2 infection significantly upregulated the mRNA and protein expression levels of N-cadherin and NCAM1 in TGCs and enhanced TGC migration, while these effects were gradually attenuated with the sequential deletion of InlA, InlB and LLO. This study clarifies the synergistic roles of InlA, InlB, and LLO in mediating the infection of trigeminal ganglion neurons by ovine-derived Lm and reveals the molecular mechanism by which Lm promotes neural invasion by regulating the expression of host cell adhesion molecules. Our findings provide important experimental data for elucidating the neural invasion pathway of Lm in ruminants and lay a theoretical foundation for the development of targeted prevention and control strategies for ruminant listeriosis in veterinary clinical practices. Full article

Alzheimer’s disease (AD), the most common cause of dementia, is characterized by progressive memory and cognitive decline. Conventional genome-wide association studies (GWAS) comparing AD cases and controls may miss genetic influences that act along a continuum of cognitive function. Using data from 3007 participants in the National Institute on Aging Late-Onset Alzheimer’s Disease Family Study (NIA-LOAD GWAS), we conducted a family-based GWAS of eight quantitative cognitive phenotypes encompassing episodic memory (Logical Memory IA and IIA), working memory (Digit Span Forward, Backward, and Ordering), and semantic fluency (Animal, Fruit and Vegetable, and Vegetable Fluency). Family-based association testing in PLINK v1.9 identified numerous single nucleotide polymorphisms (SNPs) associated with cognitive phenotypes at genome-wide significant (p < 5 × 10⁻⁸) levels. Notably, genome-wide significant variants with cognatic functions were localized to genes implicated in synaptic function, neurodevelopment, and neurodegeneration, including TOMM40 (rs2075650), ERBB4 (rs1521543), APLP2 (rs12281267, rs959354), PTPRD (rs1353983, rs970347, rs1392511), NCAM2 (rs2826728), GRM7 (rs6788201), PAX5 (rs2988003, rs2381595), NRG1 (rs16875655), and NRG3 (rs1937957). Furthermore, the TOMM40 (rs2075650) was significantly associated with AD as a binary outcome (p = 4.60 × 10⁻²⁴) and APLP2 (rs12281267, rs959354), APOE (rs405509), PTPRD (rs1353983, rs970347, rs1392511) were associated with AD (p < 0.001). Additionally, several pathways including the ERBB4 signaling pathway (adjusted p = 2.82 × 10⁻³), driven by ERBB4, NRG1, and NRG3 may contribute to cognitive impairments. This study provides a comprehensive resource of cognitive endophenotype associations in AD families, advancing understanding of the genetic architecture underlying memory, executive function, and cognitive aging, and highlights new therapeutic targets for replication and functional follow-up. Full article

Natural killer (NK) cells are effector cells of the innate immune system. The cytokine microenvironment influences NK cell function. Dysregulation of NK cell cytotoxicity can manifest in reproductive disorders and is also observed in tumor-transformed tissues. The search for immunotherapies capable of regulating NK cell activity is therefore relevant. This study aimed to evaluate the effect of the TGFβ signaling pathway inhibitor and the cyclin-dependent kinase (CDK) 7/12/13 inhibitor on the transcriptional profile of NK-92 cell line. In the study, the cytokines TGFβ1, IL-12, IL-15, IL-18, and TNFα, and the TGFβ receptor type 1 (TGFβR1) inhibitor LY3200882 and the CDK7/12/13 inhibitor THZ1 were used. The cells were cultured sequentially in the presence of inhibitors and cytokines, followed by assessment of the gene expression of NCR2, NCR3, AHR, NCAM1, B3GAT1, EOMES, GATA3, KLRC1, KLRC2, CCL5, IL10 and TBX21. We observed direct effects of the inhibitors on NK cells. LY3200882 increased the expression of KLRC1 and B3GAT1, and reduced NCAM1. THZ1 increased the expression of KLRC1, KLRC2, AHR and EOMES, while it reduced IL-10 and NCR2. IL-12, IL-15, IL-18, and TNFα modified the gene expression of some phenotypic and cytotoxic receptors and transcription factors. TGFβ1 increased the expression of KLRC1, NCAM1, and B3GAT1. Blocking TGFβ-dependent signaling with LY3200882 abolished TGFβ1 effects. We assessed CD56 presence on NK-92 cell membrane and found its increase in the presence of LY3200882. After LY3200882 treatment, in the presence of TGFβ1 and choriocarcinoma cell line JEG-3, the expression of CD56 receptor on NK cell membrane decreased. Pretreating NK cells with THZ1 decreased the expression of NCAM1, B3GAT1, and EOMES in the presence of TGFβ1. Thus, LY3200882 partially neutralized TGFβ1 effects on the expression of NK cell receptor genes. THZ1 followed by TGFβ1 treatment promoted NK cell transcriptional profile characteristic for CD56dim NK cells. Both LY3200882 and THZ1 affected the NK cell transcription even without cytokine treatment. The independent effects of synthetic inhibitors on NK cells, as well as their influence in the presence of tumor cells, should be considered. Full article

Polysialic acid (PSA), a highly negatively charged glycan attached mainly to the neural cell adhesion molecule (NCAM), is emerging as a critical but underrecognized extracellular regulator of glutamatergic neurotransmission. While previous literature has focused on PSA’s developmental roles, increasing evidence indicates that PSA–NCAM also contributes to synaptic plasticity mechanisms in the mature brain. This review integrates evidence from structural biophysics, single-channel electrophysiology, and disease models to explain how PSA modulates glutamate receptor gating to control learning and memory. We synthesize findings from biochemical reconstitution, electrophysiological recordings, and in vivo studies to show that PSA can modulate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor open probability, burst duration, and cooperative gating without affecting conductance, thereby promoting long-term potentiation. Conversely, PSA selectively suppresses GluN2B-containing extrasynaptic N-methyl D-Aspartate (NMDA) receptor activity by lowering open probability and calcium influx, maintaining an optimal balance between potentiation and depression while providing neuroprotection. Disruption of PSA–NCAM signaling in developmental and disease models, including prenatal cannabinoid exposure and neurodegeneration, produces cognitive deficits reversible by PSA restoration. Notably, much of the current evidence derives from in vitro systems, with relatively few studies conducted in vivo, and studies employing PSA mimetics mostly, which should be considered when interpreting physiological relevance. Collectively, the available evidence suggests that PSA functions as an extracellular modulator linking synaptic glycans to glutamate receptor regulation and plasticity related signaling pathways, highlighting the potential importance of extracellular glycan mechanisms in the control of synaptic function. Full article

This study examines the distinct roles of the neural cell adhesion molecules Ncam1a and Ncam1b in zebrafish neuromasts during both homeostasis and hair cell regeneration. While both molecules contribute to the initial development of the lateral line system, previous work showed that a morpholino knockdown of ncam1b causes more severe developmental defects than ncam1a knockdown. However, in ncam1b mutants, only minor changes in FGF/Wnt signaling and cell proliferation are observed in the migrating primordium, which do not affect overall development of the lateral line development, suggesting compensation by Ncam1a. This work shows that after neomycin-induced hair cell loss, only Ncam1b is strongly re-expressed in regenerating hair and support cells. ncam1b mutants show delayed hair cell regeneration, with an increased number of proliferating support cells but impaired differentiation into hair cells. Notably, Ncam1a is not re-expressed during regeneration in ncam1b mutants. These regeneration defects likely arise from disrupted interactions of signaling pathways. Our data suggest that Ncam1b supports regeneration by sustaining the FGF pathway activity required for atoh1a induction. It also maintains balanced Notch signaling, which regulates support cell fate decisions. Together, these results highlight the crucial, non-redundant role of Ncam1b in coordinating signaling pathways to ensure proper hair cell regeneration in zebrafish neuromasts. Full article

Background: Hilar cholangiocarcinoma (HC) is a highly aggressive malignancy with a poor prognosis, highlighting the urgent need to elucidate its molecular drivers. This study aimed to systematically identify and functionally validate key genes and pathways driving HC pathogenesis. Methods: RNA sequencing (RNA-seq) was performed on paired primary HC tumors and matched adjacent non-tumorous tissues to identify differentially expressed genes (DEGs). Subsequent bioinformatic analyses, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and protein–protein interaction (PPI) network construction, were conducted to characterize the functional landscape and identify hub genes. Transwell assays and orthotopic metastatic models were used to investigate the functions of Contactin-1 (CNTN1) in HC invasion in vitro and metastasis in vivo. Results: RNA-seq analysis identified 35 DEGs in HC, mainly involved in cell adhesion, cytoskeletal regulation, and axon development. PPI network analysis identified six hub genes, including CNTN1, NCAM1, PLP1, GPM6B, SLC1A3, and PMP2. Furthermore, we demonstrated that CNTN1, a neuronal membrane glycoprotein, was markedly up-regulated in HC at both mRNA and protein levels, and its elevated expression correlated with poor prognosis. Gain- and loss-of-function studies demonstrated that CNTN1 promotes HC cell invasion in vitro and metastasis in vivo. Mechanistically, CNTN1 exerts its pro-invasive effects by activating the PI3K-AKT signaling pathway and inducing epithelial–mesenchymal transition (EMT). Conclusions: Our integrated analysis identifies CNTN1 as a critical oncogenic driver in HC, promoting metastasis through PI3K-AKT-mediated EMT. These findings nominate CNTN1 as a potential prognostic biomarker and therapeutic target in HC. Full article

Genome editing of late myogenic regulators provides a way to dissect the mechanisms through which transcriptional programs and growth-related signaling pathways shape muscle gene expression programs in farmed fish. This study disrupted myogenic regulatory factor 4 (MRF4) in Nile tilapia using CRISPR/Cas9 to examine downstream transcriptional changes in fast skeletal muscle across the trunk, belly, and head regions. Adult F0 crispants carried a frameshift mutation that truncated the basic helix–loop–helix domain and showed an approximate 80–85% reduction in MRF4 mRNA across the trunk, belly, and head muscles. The expression of 23 genes representing myogenic regulatory factors, MEF2 paralogs, structural and contractile components, non-myotomal regulators, cell adhesion and fusion-related transcripts, and growth-related genes within the GH–IGF–MSTN axis was quantified and compared between wild-type and MRF4-crispants. Expressions of major structural genes remained unchanged despite MRF4 depletion, whereas MyoG and MyoD were upregulated together with MEF2B and MEF2D, indicating strong transcriptional compensation. Twist1, ID1, PLAU, CDH15, CHRNG, NCAM1, MYMK, GHR, and FGF6 were also significantly elevated, while IGF1 was reduced, and MSTN remained stable. Together, these results show that MRF4 loss is associated with coordinated transcriptional changes in regulatory and growth-related pathways, while major fast-muscle structural and contractile transcript levels remain stable, thereby highlighting candidate transcriptional targets for future studies that will evaluate links to muscle phenotype and growth performance in Nile tilapia. Full article

Background and Clinical Significance: We present an 85-year-old male case of primary hepatic SCC manifesting as multiple liver nodules with atypical imaging findings. Case Presentation: The patient was negative for hepatitis B surface antigen and hepatitis C virus antibody. Serum tumor markers were all within normal limits. Contrast-enhanced ultrasonography with perflubutane demonstrated hypervascular nodules in the early vascular phase, early washout in the portal phase, and a defect in the postvascular phase (10 mm in S5 and 25 mm in S6). Histopathological examination revealed irregularly shaped tumor cells with large hyperchromatic nuclei and basophilic cytoplasm, surrounded by dense fibrous stroma forming cords, solid nests, and sheet-like structures. Immunohistochemical analysis showed positivity for AE1/AE3, p40, CK5/6, c-kit, and NCAM. Conclusions: The lesions were diagnosed as primary hepatic squamous cell carcinoma and suggested the possible involvement of hepatic progenitor cells, supporting the hypothesis of de novo carcinogenesis. Full article

Neuronal development relies on cell-surface glycoconjugates that function as complex bioinformational codes. Recently, altered glycosylation has emerged as a central mechanistic theme in the pathophysiology of autism spectrum disorder (ASD). Critically, the brain maintains a distinctively restricted glycan profile through strict biosynthetic regulation, creating a specialized landscape highly susceptible to homeostatic perturbation. This “membrane-centric vulnerability” spans both glycoproteins and glycolipids; however, evidence remains fragmented, obscuring their pathogenic interplay. To bridge this gap, this review synthesizes evidence for these two primary classes of membrane glycoconjugates into a unified framework. We examine how defects in key glycoproteins (such as NCAM1 and neuroligins) directly impair synaptic signaling, trafficking, and plasticity. We then demonstrate how these defects are functionally coupled to the glycolipid (ganglioside) environment, which organizes the lipid raft platforms essential for glycoprotein function. We propose that these two systems are not independent but represent a final common pathway for diverse etiological drivers. Genetic variants (e.g., MAN2A2), environmental factors (e.g., valproic acid), and epigenetic dysregulation (e.g., miRNAs) all converge on this mechanism of impaired glycan maturation. This model elucidates how distinct upstream causes can produce a common downstream synaptic pathology by compromising the integrity of the membrane signaling platform. Full article

The expression of polysialic acid (polySia) on the neuronal cell adhesion molecule (NCAM) is called NCAM-polysialylation, which is strongly related to the migration and invasion of tumor cells and aggressive clinical status. During the NCAM polysialylation process, polysialyltransferases (polySTs), such as polysialyltransferase IV (ST8SIA4) or polysialyltransferase II (ST8SIA2), can catalyze the addition of CMP-sialic acid (CMP-Sia) to the NCAM to form polysialic acid (polySia). In this study, the docking models of polysialyltransferase IV (ST8Sia4) protein and different ligands were predicted using Alphafold 3 and DiffDock servers, and the prediction accuracy was further verified using the NMR experimental spectra of the interactions between polysialyltransferase domain (PSTD), a crucial peptide domain in ST8Sia4, and a different ligand. This combination strategy provides new insights into a quick and effective screening for inhibitors of tumor cell migration. Full article

Neuroblastoma (NB), a pediatric cancer of sympatho-adrenal (SA) lineage, is marked by disrupted differentiation and cellular heterogeneity. INSM1, a zinc-finger transcription factor, is highly expressed in NB and developing SA tissues, where it regulates neuroendocrine differentiation, especially in chromaffin cells. We investigated INSM1’s role in maintaining an undifferentiated, progenitor-like state in NB and its regulation via metabolic and epigenetic mechanisms. Transcriptomic profiling, promoter assays, and metabolic flux analysis revealed that INSM1 expression correlates with methionine cycle activity, particularly the S-adenosylmethionine (SAM)/S-adenosylhomocysteine (SAH) ratio. Disruption of SAM/SAH balance altered INSM1 promoter activity and histone methylation, implicating epigenetic control in NB cell fate. Retinoic acid-induced differentiation downregulated INSM1 and N-Myc, linking INSM1 to tumor cell immaturity. INSM1 overexpression in SH-SY-5Y cells upregulated neuroendocrine and thyroid hormone-related genes (CHGA, CHGB, DDC, NCAM1, DIO3, TH), while suppressing genes involved in cell cycle (RRM, CDC25A), methionine metabolism (AHCY, MAT2A), transcriptional regulation (MYBL2, EZH2), and oncogenic signaling (ALK, LINC011667). These findings suggest that INSM1 promotes NB aggressiveness by sustaining a neuroendocrine progenitor-like phenotype through metabolic-epigenetic coupling. Full article

Pure membranous lupus nephritis (pMLN, ISN/RPS-class V) is a rare form of lupus nephritis (LN). Despite being associated with significant comorbidities, it has traditionally been considered a less aggressive subtype. Emerging data challenges this perception, highlighting its potential for chronic kidney disease progression and kidney failure. pMLN is pathologically defined by subepithelial immune-complex deposits and typically presents with nephrotic syndrome, preserved renal function, and fewer systemic/immunologic manifestations compared to proliferative LN (ISN/RPS-classes III/IV). Repeat biopsies reveal frequent histological class switching from pMLN to proliferative and mixed LN forms, underscoring the dynamic nature of the disease and the limitations of clinical markers in reflecting histological activity. While the ISN/RPS kidney biopsy classification provides important prognostic insight, it does not fully capture underlying molecular heterogeneity. Recent advances in precision medicine, including proteomic and biomarker studies (e.g., EXT1/2, NCAM1), offer promising tools for patient stratification and tailored treatments. International guidelines now recommend immunosuppressive therapy for pMLN, aligning treatment strategies more closely with those for proliferative and mixed LN. Overall, pMLN should be considered a distinct but clinically relevant LN subtype requiring personalized management based on clinical, histological and molecular features. Long-term monitoring is essential, as baseline presentation does not reliably predict treatment response or disease trajectory. Full article

Aging of the gut involves progressive changes in structure, function, and microbial composition, which impact overall health. The vermiform appendix extends from the apex of the cecum; it contains gut-associated lymphoid tissue and serves as a reservoir of gut microbiota. This study investigates histologic and gene expression changes in 20 morphologically normal appendiceal samples obtained from pediatric (n = 5), adult (n = 8), and geriatric (n = 7) patients. Histologic analysis revealed a higher prevalence of lymphoid follicles reduction and the presence of fibrous obliteration of the appendiceal tip in aged samples. RNA sequencing identified 1004 differentially expressed genes (385 upregulated and 619 downregulated; p < 0.05) between the adult and geriatric population. Upregulated pathways were enriched for oxidative stress response, cholesterol metabolism, and mucosal barrier maintenance, including NRF2 targets (NQO1, MGST1), suggesting enhanced antioxidant activity. Downregulated genes were associated with synaptic signaling, ion channel regulation, and neuronal adhesion (e.g., GRIA2, RET, NOS1, NCAM2, CNTN1), reflecting age-related decline in enteric neuronal integrity. Across all age groups, 25 protein-coding genes showed progressive expression shifts with aging, including upregulation of CLDN2, MUC2, and GDF15, and downregulation of NOG and NELL2, indicating barrier loosening, chronic inflammation, and reduced regenerative potential. These findings suggest that aging of the vermiform appendix recapitulates key processes of intestinal aging, including oxidative stress, inflammaging, and neuronal loss, supporting its potential use as a model tissue for studying gut aging mechanisms. Full article

Proteomics of dystrophic muscle samples is limited by the amount of protein that can be extracted from patient biopsies. Cells and tissues derived from patient-derived induced pluripotent stem cells (iPSCs) can be an expandable alternative source. We have patterned iPSCs from three Duchenne muscular dystrophy (DMD) patient lines into skeletal muscle cells using a two-dimensional as well as our three-dimensional organoid differentiation system. Probes with sufficient protein amounts could be extracted and prepared for mass spectrometry. In total, 3007 proteins in 2D and 2709 proteins in 3D were detected in DMD patient probes. A total of 83 proteins in 2D and 338 proteins in 3D can be described as differentially expressed between DMD and control patient probes in a post hoc test. We have identified and we propose Myosin-9, Collagen 18A, Tropomyosin 1, BASP1, RUVBL1, and NCAM1 as proteins specifically altered in their expression in DMD for further investigation. Proteomics of skeletal muscle organoids resulted in greater consistency of results between cell lines in comparison to the two-dimensional myogenic differentiation protocol. Full article