Search Results (363)

Background: Malignant salivary gland tumors represent a highly diverse group of neoplasms, their heterogeneity likely arising due to variable origin in different tissue components. Emerging evidence suggests that SOX-2 and EZH-2 play critical roles in salivary gland carcinogenesis, being related to tumor cell stemness potential, along with accelerated tumor progression and unfavorable clinical outcomes. The aim of this study was to assess the association between SOX-2 and EZH-2 expression, survival parameters, and tumors’ pathological characteristics in a group of patients with primary epithelial malignant salivary gland tumors (MSGTs) and to evaluate their value as diagnostic and prognostic markers. Methods: Our study group comprised 104 patients with primary epithelial MSGTs diagnosed in “Sf. Spiridon” County Hospital, Iasi, over a period of fifteen years. Pathological parameters and survival evaluation, along with SOX-2 and EZH-2 immunohistochemistry assessment and scoring, were conducted, and the associations between different parameters were analyzed. Results: High SOX-2 immunoexpression was significantly associated with lymphatic invasion (LY) (p = 0.003), pT stage (p = 0.010), histological tumor type (p = 0.003), and tumor grading (p = 0.037), while high EZH-2 immunoexpression was significantly associated with perineural invasion (PnI) (p < 0.001), vascular invasion (p = 0.038), LY (p = 0.001), tumor grading (p = 0.002), and pathological extranodal extension (pENE) (p = 0.018). The tumors with high SOX-2 and EZH-2 expressions were associated with a reduced overall survival (OS) (p = 0.013 and p = 0.011). Cox regression analysis revealed that pT (HR = 1.826, p = 0.019), LY (HR = 0.318, p = 0.007), and tumor grade (HR = 0.505, p = 0.021) added to high SOX-2 and EZH-2 immunoexpression independently predicted a poor survival outcome (HR = 2.373, p = 0.016 and HR = 2.746, p = 0.015). Conclusions: Our findings suggest that SOX-2 and EZH-2 may serve as biomarkers of aggressive behavior and a poor prognosis in primary epithelial MSGTs, providing potential opportunities for precision-targeted therapies. Full article

Cutaneous T-cell lymphoma (CTCL) comprises a heterogeneous group of extranodal non-Hodgkin lymphomas. With the publication of the fifth edition of the World Health Organization Classification of Hematolymphoid Tumors, the diagnostic framework for CTCL has shifted from primarily morphologic phenotypes toward an emphasis on molecular drivers. Current research suggests that malignant clones may arise from somatic mutations at the hematopoietic stem cell stage and may follow a continuous hematogenous dissemination model with bidirectional trafficking between the skin and systemic circulation. At the molecular level, genomic instability, often associated with somatic copy-number variations, may promote activation of the janus kinase-signal transducer and activator of transcription (JAK/STAT) signaling pathway through gene-dosage effects. In parallel, chromatin remodeling linked to EZH2 overexpression and reduced special SATB1 expression may support a Th2-polarized program. This phenotype may contribute to epidermal barrier impairment via cytokines such as Interleukins-4 (IL-4) and IL-13, potentially creating conditions permissive for Staphylococcus aureus colonization. Microbial superantigens and exotoxins may further contribute to tumor progression and therapeutic resistance by reinforcing JAK/STAT signaling, particularly STAT3, and reducing CD8+ T-cell–mediated immune surveillance. In the dermis, reprogramming of cancer-associated fibroblasts and polarization of macrophages toward an M2 phenotype may collectively contribute to an immunosuppressive niche. Emerging biomarkers, including CD74, and acquired resistance mechanisms after anti-C-C chemokine receptor 4 therapy further extend the translational relevance of recent pathologic findings. Overall, CTCL evolution appears to be a systemic process shaped by interactions between tumor-intrinsic genetic alterations and the skin microenvironment. Full article

Neuroblastoma (NB) represents a paradigmatic developmental malignancy in which lineage specification, oncogenic signalling, and epigenetic regulation converge to define tumour behaviour. Among the molecular axes shaping NB heterogeneity, neurotrophin receptors of the tropomyosin receptor kinase (Trk) family (TrkA, TrkB, and TrkC) and the p75NTR occupy a central position at the intersection between neuronal differentiation programs and malignant plasticity. While high TrkA and TrkC expression is associated with adrenergic identity, differentiation competence, and favourable clinical outcome, TrkB, frequently sustained by BDNF-driven autocrine loops, characterises mesenchymal-like, therapy-resistant states enriched in metabolic and inflammatory adaptations. Importantly, in NB, the dysregulation of neurotrophin signalling rarely arises from recurrent genetic alterations of neurotrophic tyrosine receptor kinase (NTRK) loci. Instead, Trk receptor expression is dynamically shaped by promoter methylation, polycomb repressive complex 2/Enhancer of Zeste homolog 2 (PRC2/EZH2)-dependent chromatin repression, MYCN-driven transcriptional silencing, enhancer rewiring, and microRNA-mediated control. These epigenetic mechanisms govern reversible transitions along the adrenergic–mesenchymal (ADRN–MES) continuum, enabling tumour cells to adapt to microenvironmental and therapeutic stress. Single-cell and spatial multi-omics approaches have further revealed that Trk-associated phenotypes are embedded within complex regulatory circuits integrating receptor tyrosine kinase (RTK) networks, cytokine signalling, metabolic remodelling, and stromal reinforcement. Here, we provide a comprehensive synthesis of the epigenetic and microenvironmental mechanisms regulating neurotrophin receptors in NB, with particular emphasis on how chromatin plasticity and cell-state transitions reshape Trk-dependent signalling outputs. We discuss advanced three-dimensional and organoid-based models that recapitulate niche-specific regulation of the Trk axis and evaluate emerging therapeutic strategies combining epigenetic modulators, differentiation-inducing agents, and RTK-targeted compounds. Understanding the temporal and spatial dynamics of Trk signalling may open new opportunities to therapeutically stabilise differentiation states and disrupt adaptive resistance programs in high-risk NB. Full article

We previously demonstrated that human herpesvirus 6A infects papillary thyroid cancer cells (BCPAP), inducing molecular changes compatible with a tumor-promoting phenotype, including increased expression of R273H mutant TP53 (mutp53), upregulation of c-Myc, and enhanced secretion of IL-6. To investigate whether and how epigenetic mechanisms contribute to these virus-induced effects, we examined the histone methyltransferase EZH2, a key regulator of chromatin repression frequently altered in cancer. HHV-6A infection reduced EZH2 expression and global H3K27me3 levels. Pharmacological inhibition of EZH2 using DS-3201 reproduced some of the molecular effects of viral infection, including increased mutp53 stability. Both viral infection and EZH2 inhibition induced delayed upregulation of SIRT1, which mediated deacetylation-dependent stabilization of mutp53 while reducing c-Myc expression. Indeed, the inhibition of SIRT1 with EX-527 reversed mutp53 accumulation but restored c-Myc expression and increased extracellular IL-6 release. This drug also reduced cell survival, suggesting that SIRT1 supports cellular adaptation to oncogenic stress triggered by EZH2 loss. Overall, our findings identify an epigenetic axis in which the HHV-6A-mediated downregulation of EZH2 induces SIRT1, regulating mutp53 stability and c-Myc expression and reshaping inflammatory signaling to maintain cell viability. These results establish a mechanistic link between viral infection, epigenetic remodeling, and oncogenic dependency. They also suggest that targeting IL-6 signaling could represent a therapeutic vulnerability in HHV-6A-associated thyroid cancer, particularly in combination with SIRT1 inhibitors. Full article

Enhancer of Zeste Homolog 2 (EZH2), the catalytic subunit of Polycomb Repressive Complex 2 (PRC2), mediates histone H3 lysine 27 trimethylation (H3K27me3), an epigenetic modification associated with transcriptional repression. EZH2 inhibitors (EZH2is) gained attention after the first-in-class drug Tazemetostat received FDA approval for treating epithelioid sarcoma. Preclinical studies suggest that EZH2is could be effective against melanoma, but their general inability to cross the blood–brain barrier (BBB), among others, limits the treatment of secondary brain metastases. Based on these limitations, we designed SG-8, a novel compound derived from TDI-6118 (a known brain-penetrant EZH2i). In silico docking predicted that SG-8 may exhibit high affinity for EZH2 as well as for another PRC2 subunit, Embryonic Ectoderm Development (EED). In addition, in vitro PAMPA assays suggested passive BBB permeability of SG-8. In cell-based assays, SG-8 and the structurally related EZH2i PF-06726304 displayed lower cytotoxicity than Tazemetostat in both primary (A375) and metastatic (Colo-679) human melanoma cells. Western blot analysis showed that SG-8 and PF-06726304 markedly reduced EED protein levels and, to a lesser extent, EZH2 levels, without affecting total H3K27me3, consistent with preserved canonical PRC2 activity. Instead, treatment with both compounds—most prominently SG-8—was associated with reduced phosphorylation levels of EZH2 (Ser21) and its upstream regulator Akt (Ser473), suggesting that modulation of the Akt–EZH2 signaling axis may at least partially contribute to their anti-melanoma activity. Full article

Extrachromosomal circular DNA (eccDNA) has emerged as a pivotal contributor to cancer progression, facilitating oncogene amplification, dysregulated gene expression, and tumor heterogeneity. Despite its significance in cancer, the interplay between eccDNA and key epigenetic regulators such as EZH2 remains largely unexplored. In this study, we systematically investigate the correlation between Tazemetostat, a highly selective EZH2 inhibitor, and alterations in the eccDNA landscape and transcriptional programs in ovarian cancer. Through integrated profiling using Circle-seq and RNA sequencing, we demonstrate that EZH2 inhibition is associated with markedly reprogrammed eccDNA dynamics. Furthermore, multi-omics integration identified that 67 genes exhibited concordant changes in both eccDNA abundance and transcript expression. Subsequent analyses also pinpointed 11 genes as putative effectors of drug response. Notably, spatial single-cell transcriptomics identified SFRP1 as the most consistently reactivated tumor suppressor across eccDNA, bulk expression, and spatial datasets, based on predefined statistical and biological criteria, by Tazemetostat. Moreover, SFRP1 was one of the genes that varied the most within cancer-associated fibroblast populations, exhibiting distinct spatial expression patterns. Taken together, this study establishes the first potential evidence that EZH2 inhibition may reprogram eccDNA dynamics to potentially restore SFRP1 tumor suppressor expression in ovarian cancer. By integrating multi-omics and spatial single-cell transcriptomics, we uncovered a novel epigenetic–eccDNA axis that may contribute to oncogenic plasticity and therapeutic resistance. This could result in a paradigm shift in targeting eccDNA-driven malignancies. Full article

Lung adenocarcinoma is the most common form of lung cancer with a 5-year survival rate of 15%, largely due to asymptomatic metastasis and late diagnosis. Overexpression of Polycomb group (PcG) proteins, particularly EZH2, the catalytic component of Polycomb Repressive Complex 2 (PRC2), has been associated with the pathogenesis of lung cancer, frequently showing correlation with cancer progression and poor prognosis. In this study, EZH2 levels were modulated by CRISPR/Cas9 gene editing and PRC2 activity was inhibited with EZH2 inhibitor EPZ6438 or EED inhibitor MAK683. EZH2 gene editing reduced cell proliferation, migration, invasion, and colony formation and reduced NFκ-B signaling activation, indicating an antitumoral effect in vitro. Moreover, EZH2 inhibition also increased the expression of differentiation-related genes, such as GATA5, FOXA2, and lung surfactants, indicating a pro-differentiation effect. However, EZH2-edited cells injected into an immunocompromised mouse model generated larger tumors compared to unedited cells. This was accompanied by increased expression of other PcG genes, including EZH1, CBX2, RING1, EED, and SUZ12, suggesting a compensatory interaction between PRC2 and PRC1 complexes. These findings provide significant clinical relevance, both in elucidating the mechanisms of novel molecular targets and in guiding treatment strategies for lung cancer when using epigenetic inhibitors. Full article

Background: Triple-negative breast cancer (TNBC) represents the most aggressive breast cancer subtype, characterized by high genomic instability, metabolic stress, and limited therapeutic options. Ferroptosis, an iron-dependent form of regulated cell death, has emerged as a promising vulnerability in TNBC, yet its subtype-specific regulatory landscape remains insufficiently defined. Methods: Using transcriptomic (METABRIC, TCGA, GEO) and proteomic (CPTAC) datasets, ferroptosis-related genes were profiled across PAM50 breast cancer subtypes. Differential expression, univariate Cox regression, LASSO modeling, survival analyses, GSEA, and dimensionality reduction (PCA, t-SNE) were applied. A Ferroptosis Index (FI) was calculated using β-coefficients from the Cox/LASSO regression model. Single-cell RNA-seq data was used to map ferroptosis-associated signature across tumor and microenvironmental compartments. Results: Basal-like tumors exhibited the strongest ferroptosis-associated transcriptional shift, characterized by upregulation of ACSL4 and EZH2 and downregulation of AR, GPX4, and CIRBP. Sixteen ferroptosis-related genes were associated with overall survival, forming a ferroptosis-associated signature. The FI was significantly higher in Basal-like tumors, indicating elevated ferroptosis-associated transcriptional state. GSEA revealed enrichment of cell cycle, mitotic, cytoskeletal, and metabolic stress pathways. Single-cell analysis demonstrated expression of ferroptosis markers across cancer epithelial, stromal, and myeloid populations. Conclusions: Basal-like tumors harbor a distinct ferroptosis-associated transcriptional state linked to tumor aggressiveness and poor prognosis. These findings provide a biologically grounded framework for ferroptosis-related stratification and support future functional and translational studies targeting ferroptosis vulnerabilities in aggressive breast cancer. Full article

The identification and targeting of lung-cancer-cell-surface proteins are important for drug development. Molecularly imprinted polymer nanoparticles (nanoMIPs) offer a synthetic approach for the recognition of proteins on the cell surfaces. This work outlines the use of a novel ‘snapshot imprinting’ approach to characterize differences in the cell-surface proteomes of lung cancer cell lines (A549, H460, H522) and a non-cancerous cell line (BEAS-2B) to potential protein targets for diagnostic and therapeutic applications. The mass spectrometry-based quantitative proteomics identified 2381 proteins. Fold change and p-value thresholds were used to define statistically and biologically significant differentially expressed proteins (DEPs) across cell lines, yielding 353, 426, and 274 DEPs for A549, H460, and H522, respectively, when compared to BEAS-2B. The DEPs identified across overlapping cell line comparisons were analyzed using Gene Ontology enrichment and a protein–protein network to identify hub proteins. Among these hub proteins, five proteins (NPM1, TOP2A, EZH2, PRKDC, and HNRNPK) were identified as clinically relevant when cross-referenced with the Human Protein Atlas database and the literature, highlighting their potential as diagnostic and therapeutic targets. These findings highlight the potential of nanoMIP-based snapshot imprinting as an alternative to ‘classical’ approaches for identifying potential protein targets for diagnostic and therapeutic applications. Full article

Metastasis is still the leading cause of cancer-related death. It happens when disseminated tumor cells (DTCs) successfully navigate a series of steps and adapt to the unique conditions of distant organs. In this review, key molecular and immune mechanisms that shape metastatic spread, long-term survival, and eventual outgrowth are examined, with a focus on how tumor-intrinsic programs interact with extracellular matrix (ECM) remodeling, angiogenesis, and immune regulation. Gene networks that sustain tumor-cell plasticity and invasion are described, including EMT-linked transcription factors such as SNAIL and TWIST, as well as broader transcriptional regulators like SP1. Also, how epigenetic mechanisms, such as EZH2 activity, DNA methylation, chromatin remodeling, and noncoding RNAs, lock in pro-metastatic states and support adaptation under therapeutic pressure. Finally, proteases and matrix-modifying enzymes that physically and biochemically reshape tissues, including MMPs, uPA, cathepsins, LOX/LOXL2, and heparinase, are discussed for their roles in releasing stored growth signals and building permissive niches that enable seeding and colonization. In parallel, immune-evasion strategies that protect circulating and newly seeded tumor cells are discussed, including platelet-mediated shielding, suppressive myeloid populations, checkpoint signaling, and stromal barriers that exclude effector lymphocytes. A major focus is metastatic dormancy, cellular, angiogenic, and immune-mediated, framed as a reversible survival state regulated by stress signaling, adhesion cues, metabolic rewiring, and niche constraints, and as a key determinant of late relapse. Tumor-specific metastatic programs across mesenchymal malignancies (osteosarcoma, chondrosarcoma, and liposarcoma) and selected high-burden cancers (melanoma, hepatocellular carcinoma, glioblastoma, and breast cancer) are highlighted, emphasizing shared principles and divergent organotropisms. Emerging therapeutic strategies that target both the “seed” and the “soil” are also discussed, including immunotherapy combinations, stromal/ECM normalization, chemokine-axis inhibition, epigenetic reprogramming, and liquid-biopsy-enabled minimal residual disease monitoring, to prevent reactivation and improve durable control of metastatic disease. Full article

Background/Objectives: The ineffectiveness of current treatments for glioblastoma underscores the urgent need for effective alternatives. This study aimed to investigate the effectiveness of sodium dichloroacetate (NaDCA) and a sodium valproate NaDCA combination (NaVPA–NaDCA) on formed patients’ primary cell tumors on the chick embryo chorioallantoic membrane (CAM). Methods: Glioblastoma tissue samples were obtained from three patients during tumor surgery. WHO grade IV, IDH wild-type, and a strong positive cytoplasmic GFAP reaction in tumor cells characterized the investigated glioblastoma cases. The tumor cells GBM2-2F, GBM2-3F, and GBM-4M from the patients were examined. Histological examination of tumor invasion into CAM, angiogenesis, and immunohistochemical expression of GFAP-, PCNA-, p53-, EZH2- and vimentin-positive cells were examined. Results: No difference in GFAP expression was observed between the patient’s GBM tumor tissue and the tumor formed on CAM from the same patient’s tumor cells. There were no significant differences in invasion or in the frequency of GFAP- and p53-positive cells among the study control groups. The expression of PCNA-, EZH2-, and vimentin-positive cells in control tumors varied significantly. Treatment significantly reduced the incidence of tumor invasion in GBM2-2F and GBM2-4M and did not affect GBM2-3F tumors; treatment also significantly reduced GFAP expression in GBM2-3F and GBM2-4M and did not affect GBM2-2F tumors. The treatment with NaVPA–NaDCA significantly reduced the expression of PCNA, p53, EZH2 and vimentin in the tested tumors. Conclusions: Data demonstrated an antitumor effect of NaVPA–NaDCA in an in vivo model of a patient’s primary glioblastoma cells. Full article

Precision medicine has reshaped the clinical management of prostate cancer by integrating comprehensive genomic profiling, biomarker-driven patient stratification, and the development of molecularly targeted therapeutics. Advances in next-generation sequencing have uncovered diverse genomic alterations—including homologous recombination repair defects, MSI-H/MMRd, PTEN loss, BRCA1/BRCA2 mutations, ATM alterations, SPOP mutations, and molecular hallmarks of neuroendocrine differentiation—that now inform individualized treatment decisions. This review synthesizes established clinical evidence with emerging translational insights to provide an updated and forward-looking overview of precision oncology in prostate cancer. Landmark trials of PARP inhibitors and PSMA-targeted radioligand therapy have redefined treatment standards for biomarker-selected patients. Concurrently, efforts to optimize immune checkpoint inhibition, AKT pathway targeting, and rational combinations with androgen receptor pathway inhibitors continue to expand therapeutic possibilities. Rapidly evolving investigational strategies—including bipolar androgen therapy (BAT), immunotherapeutic approaches for CDK12-altered tumors, targeted interventions for SPOP-mutated cancers, and epigenetic modulation such as EZH2 inhibition for neuroendocrine prostate cancer—further illuminate mechanisms of tumor evolution, lineage plasticity, and treatment resistance. Integrating multi-omics technologies, liquid biopsy platforms, and AI-assisted imaging offers new opportunities for dynamic disease monitoring and biology-driven treatment selection. By consolidating current clinical practices with emerging experimental directions, this review provides clinicians and researchers with a comprehensive perspective on the evolving landscape of precision medicine in prostate cancer and highlights future opportunities to improve patient outcomes. 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

Triple Negative Breast Cancers (TNBCs) are heterogeneous and aggressive tumors with a median overall survival of less than two years. Despite the availability of new drugs, the prognosis remains poor, implicating a more aggressive clinical course in the metastatic setting. This study investigated the effects of metronomic treatment (mCHT) with 5-fluorouracil (5-FU) plus vinorelbine (VNR) on spheroids derived from two different TNBC cell lines (BT-549 and MDA-MB-231) and a patient-derived primary cell line (MS-186). mCHT significantly reduced spheroid growth and altered spheroid architecture, with a pronounced effect in second-generation spheroids, enriched in self-renewing cancer stem cells (CSCs). Expression of CSC-related markers (CD44, CD133, NOTCH-1, and MYC) was more significantly altered—both at the mRNA and protein levels—by mCHT than by standard treatment (STD). In MS-186-derived spheroids, mCHT downregulated EZH2 and STAT3, key regulators of CSC maintenance, and reduced H3K27ac, suggesting a global epigenetic reprogramming. Unlike STD, which partially and transiently reduced stemness markers, mCHT achieved sustained suppression, indicating preferential targeting of therapy-resistant CSCs. These results indicate mCHT as a promising strategy for specifically aiming at the CSC-like compartment in TNBC, underscoring a therapeutic approach that reprograms key epigenetic networks and overcomes resistance to treatment. Full article