Neuroblastoma, the predominant extracranial solid malignancy in the pediatric population, remains a major clinical challenge due to pronounced intratumoral heterogeneity and intrinsic therapeutic resistance. 4-Methoxydalbergione (4-MD), a benzoquinone derivative isolated from Dalbergia odorifera, has demonstrated anticancer activity in several tumor models; however, its effects and underlying cell death mechanisms in neuroblastoma remain unclear. Here, we investigated the cytotoxic effects of 4-MD in human neuroblastoma cells using cell viability assays, flow cytometry, immunoblotting, and fluorescence microscopy. 4-MD reduced cell viability in a dose- and time-dependent manner and induced caspase-3 cleavage accompanied by MAPK activation, indicating apoptotic cell death. Concurrently, 4-MD promoted autophagosome accumulation, as evidenced by LC3-II accumulation, acidic vesicular organelle formation, ATG5 upregulation, and p62 degradation, in association with activation of the AMPK/mTOR/ULK1 signaling axis. Pharmacological inhibition of autophagy significantly attenuated 4-MD-induced cytotoxicity without affecting caspase-3 activation, demonstrating a caspase-independent, pro-death role of autophagy. Reactive oxygen species (ROS) acted as a critical upstream mediator, as antioxidant treatment suppressed both apoptotic and autophagic signaling. Moreover, inhibition of Na⁺,K⁺-ATPase with ouabain selectively reduced autophagy-dependent cell death, implicating autosis as an additional mechanism. Notably, 4-MD exhibited minimal toxicity toward primary cortical neurons. Collectively, these findings demonstrate that 4-MD engages multiple, non-redundant cell death pathways through coordinated ROS-MAPK-AMPK/mTOR/ULK1 signaling, highlighting its potential to overcome therapeutic resistance in heterogeneous neuroblastoma cells.

Advanced therapy medicinal products require rigorous preclinical testing to exclude tumorigenicity. Human articular cartilage cells expanded at low density with human platelet lysate show enhanced proliferation, matrix production, and immunomodulatory properties, supporting their use for diffuse cartilage lesions in osteoarthritic joints. This study evaluated tumorigenicity and biodistribution of cartilage cell spheroids generated using two platelet lysate sources.

Cartilage cells were expanded at low density with two platelet lysates and assembled into spheroids. Cytogenetic stability was assessed by metaphase karyotyping following expansion. Immunodeficient mice received subcutaneous implantation and were monitored for 180 days. Human colon carcinoma cells and mouse fibroblasts were used as controls. Clinical follow-up, full organ histopathology, and immunohistochemistry were performed to detect human cell persistence.

Expanded cartilage cells showed predominantly normal karyotypes, with rare low-level mosaic chromosomal alterations not detected at the previous passage. Cartilage cell spheroids were well tolerated in vivo, with complete survival and no evidence of tumorigenicity, inflammation, or human cell persistence at implantation sites or distant organs. Control experiments confirmed the sensitivity of the model, and no systemic toxicity was observed.

Spheroids derived from cartilage cells are non-tumorigenic, non-migratory, and biologically safe in immunodeficient mice. These findings support their development as cell-based cartilage therapies and align with regulatory recommendations for non-clinical safety evaluation.

Glioblastoma multiforme (GBM) is the most lethal primary brain tumor in adults. Emerging evidence endorses that gut dysbiosis contributes to GBM progression through the gut-brain axis (GBA), promoting inflammation and therapeutic resistance via abnormal short-chain fatty acid production and cytokine dysregulation. Exosomes, naturally occurring nanovesicles (30-150 nm), offer promising therapeutic potential due to their blood-brain barrier permeability, biocompatibility, and versatile cargo capacity. This review examines exosome engineering strategies for dual targeting: inhibiting alterations in gut microbiome and inducing regulated cell death mechanisms such as apoptosis and ferroptosis in GBM. We describe exosome engineering with detailed focus on cargo loading approaches (e.g., genetic modification, electroporation, and sonication), exosome surface functionalization with specific ligands (e.g., antibodies), and exosome biogenesis pathway manipulation. Engineered exosomes can deliver anti-inflammatory agents and gut microbiome modulators to restore GBA homeostasis while simultaneously transporting tumor-suppressive non-coding RNAs (e.g., miRNAs, siRNAs) and therapeutic agents to induce apoptosis by overcoming temozolomide resistance, and trigger ferroptosis-inducing components in GBM stem cells. Preclinical studies make obvious that this dual-targeting approach ought to enhance therapeutic efficacy by creating systemic immunity and eliminating tumor cells. However, clinical translation brings forth challenges, such as manufacturing, targeting specificity, and standardized quality control, and warrants further study.

Cancer stem cells (CSCs) are increasingly recognized as central drivers of tumorigenesis, therapeutic resistance, and recurrence across diverse malignancies. This review synthesizes our current understanding of CSC biology across CNS tumors, with a focus on glioblastoma, where stem-like cells are sustained by specialized and overlapping tumor microenvironmental niches. Perivascular, hypoxic, invasive, immunosuppressive, and extracellular matrix-associated niches cooperatively enforce stemness, metabolic adaptability, immune evasion, and phenotypic plasticity, enabling CSC persistence despite maximal surgical resection and standard-of-care therapy. Notably, CSCs extend beyond radiographically defined tumor margins and populate peritumoral regions, providing a biological basis for near-universal recurrence. Advances in multiparametric imaging, stem cell-based ex vivo and in vivo models, and single-cell and spatial profiling have refined insight into CSC heterogeneity, niche dependence, and treatment resistance. Together, these findings reframe therapeutic strategies, highlighting the need for function-preserving maximal resection and multimodal therapies that target both CSC-intrinsic pathways and their supportive microenvironments.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by immune cell dysfunction and poor prognosis. CD44, a cell surface glycoprotein with multiple splice variants, has been implicated in tumor progression, but its compartment-specific roles in PDAC remain unclear. CD44 standard and variant isoform expression was analyzed in patient-derived lymph nodes (LNs) by quantitative PCR. Immune cell-specific CD44 expression was assessed by flow cytometry in LNs and peripheral blood. Soluble and exosome-associated CD44 (exo-CD44) were measured in plasma. Clinical associations and survival analyses were performed. Transcriptomic, immune infiltration, immune checkpoint, and drug sensitivity analyses were conducted using TCGA-PAAD and pharmacogenomic datasets. CD44 standard isoform expression was unchanged in PDAC LNs, whereas multiple CD44 variant isoforms (v4-v10) were significantly reduced and associated with metastatic disease and poor survival, particularly CD44v5, v6, v7, and v10. CD44 expression was enriched in CD45⁺ immune cells, with highest levels in CD4⁺ T cells in both LNs and blood. Soluble CD44 levels showed no clinical associations. In contrast, exo-CD44 levels were reduced overall in PDAC but increased in patients with distant metastasis, positive resection margins, systemic inflammation, and reduced survival. High CD44 expression was associated with advanced disease, immune cell infiltration, immune checkpoint gene expression, reduced sensitivity to gemcitabine, paclitaxel, rapamycin, and FMK, and distinct CTLA4/PD-L1 checkpoint profiles. CD44 exhibits compartment-specific regulation in PDAC, linking immune remodeling, exosome signaling, and therapeutic resistance to adverse clinical outcome.

Many cancer-associated deaths result from metastases rather than primary tumors. Growing evidence suggests that DNA methylation alterations are crucial for inducing a plastic phenotype that allows cancer cells to adapt to the metastatic microenvironment. Brain metastases of melanoma (MBM) and glioblastoma (GB) share a neuroectodermal origin and the brain as tissue of residence, but their epigenetic regulation is poorly understood. Aiming at elucidating shared and tumor-distinct features, we analyzed the methylation of MGMT regulatory elements. We focused on MGMT because MGMT promoter methylation is used as a predictive marker for temozolomide response in GB, but its role in MBM has been discussed controversially. By targeting 12 CpG dinucleotides (CpGs) in the promoter, 68 CpGs in intergenic enhancers, and 31 CpGs in intragenic enhancers, we identified shared features, including an L-shaped relationship between promoter methylation and MGMT protein expression and an inverse L-shaped relationship between intragenic enhancer methylation and MGMT protein expression. GB exhibited higher methylation, particularly in promoter and intergenic enhancers, and stronger associations between methylation and overall survival than MBM. These results highlight both conserved and tumor-specific MGMT regulation, reflecting the complexity of epigenetic control in brain malignancies and emphasizing divergent evolution between MBM and GB.

Antiepileptic drugs (AEDs) are primarily indicated for controlling epileptic seizures. However, accumulating clinical evidence suggests that their benefits in patients with central nervous system (CNS) tumors extend beyond seizure management. Emerging evidence indicates that AEDs possess direct antitumor activity independent of their antiepileptic effects, highlighting a promising novel direction for CNS tumor therapy. This review elucidates the multifaceted antitumor mechanisms of classic (e.g., valproic acid and levetiracetam) and novel (e.g., cannabidiol) AEDs, including their impacts on metabolic reprogramming, epigenetic regulation, endoplasmic reticulum stress and unfolded protein response (ERS-UPR), ion homeostasis, and the tumor immune microenvironment (TIME) to provide new insights and a theoretical basis for developing multitarget therapeutic strategies.

Innate-like T cells (ILTCs) link innate immune responses with adaptive immune functions. This group includes invariant natural killer T (iNKT) cells, mucosa-associated invariant T (MAIT) cells, and γδ T cells. ILTCs detect transformed or stressed cells via non-classical antigen presentation pathways. For example, iNKT cells recognize CD1d-presented glycolipids, MAIT cells respond to MR1-presented metabolites from riboflavin pathways, and γδ T cells sense phosphoantigens through butyrophilin-dependent mechanisms and stress ligands. These features support early tumor control and shape downstream immunity by promoting dendritic cell activation, NK cell function, and priming of tumor-reactive CD8⁺ T cells. In established tumors, ILTC activity is frequently suppressed. Reduced antigen presentation, inhibitory cytokines, hypoxia, and metabolic constraints, including lactate accumulation and kynurenine production, limit effector responses and promote hyporesponsive states. Transcriptional regulators such as TOX, NR4A family members, and BATF are associated with these programs. This review discusses ILTC roles in tumor surveillance, immune escape, and therapeutic strategies to restore their function.

Chondrosarcomas (ChSs) are mesenchymal chemo- and radiation-resistant tumors, representing the second most frequently diagnosed bone sarcoma after osteosarcoma and 20% of all bone sarcomas. Most of ChS patients have a good prognosis after complete surgical resection. Conversely, patients with inoperable disease, due to the tumor location or metastatic dissemination, represent a great clinical challenge due to the lack of effective therapeutic options. In this study, to the best of our knowledge, we document, for the first time in human ChS tissues, the existence of CD-31- and Podoplanin-negative vascular-like channels containing red blood cells, allowing us to hypothesize the occurrence of vasculogenic mimicry (VM) in ChSs. By using patient-derived ChS cells and a stabilized ChS cell line, we demonstrate that ChS cells are able to form in vitro tubules apparently similar to those formed by endothelial cells. Further characterization of these vessels revealed the pivotal role of the Urokinase Plasminogen Activator Receptor (uPAR) in mediating the capability of ChS cells to form VM. Finally, we provide evidence that, unlike bevacizumab, which did not exert any effect, the uPAR-derived antiangiogenic peptide RI-3 behaves as a potent inhibitor of VM.

V-set and immunoglobulin domain-containing 1 (VSIG1) is a member of the immunoglobulin superfamily that has attracted increasing attention as a differentiation-associated protein in gastrointestinal neoplasia. Although initially described as a gastric-specific marker, accumulating evidence indicates that VSIG1 more accurately reflects gastric-enriched epithelial differentiation rather than strict anatomical origin. This conceptual shift has implications for phenotype-oriented tumor classification and diagnostic interpretation in the context of lineage plasticity. A structured and transparently reported literature search was conducted in PubMed/MEDLINE, Web of Science, and Scopus, covering studies published between 2000 and 2024. Eligible studies included original research and relevant reviews evaluating VSIG1 expression in normal tissues and digestive tract tumors, with emphasis on immunohistochemical patterns and clinicopathological correlations. In gastric cancer, VSIG1 expression consistently correlates with preserved glandular architecture and epithelial differentiation, whereas reduced or absent expression accompanies dedifferentiation and architectural disorganization. Outside the stomach, VSIG1 positivity is uncommon but reproducible in tumors exhibiting gastric-type or mixed differentiation, including settings of hepato-gastric phenotypic overlap. These patterns support interpretation of VSIG1 as a context-dependent indicator of lineage engagement and differentiation state rather than tumor origin or aggressiveness. Current data on independent prognostic value are limited and partially conflicting, and predictive roles remain unsupported, while functional data remain limited.