Search Results (1,096)

Osteosarcoma (OS) is the most common primary bone malignancy in children and adolescents, which is also considered an aggressive disease due to its rapid growth rate, ability to metastasize early, and complex and heterogeneous tumor microenvironment (TME). Although we are developing improved surgical and chemotherapeutic approaches, the presence of metastatic or recurrent disease is still detrimental to the patient’s outcome. Major advances in understanding the molecular mechanisms of OS are needed to substantially improve outcomes for patients being treated for OS. This review integrates new data on the molecular biology, pathophysiology, and immune landscape of OS, as well as introducing salient areas of tumorigenesis underpinning these findings, such as chromothripsis; kataegis; cancer stem cell dynamics; and updated genetic, epigenetic, and glycosylation modifiers. In addition, we review promising biomarkers, diagnostic platforms, and treatments, including immunotherapy, targeted small molecule inhibitors, and nanomedicine. Using genomic techniques, we have defined OS for its significant genomic instability due to TP53 and RB1 mutations, chromosomal rearrangements, and aberrant glycosylation. The TME is also characterized as immunosuppressive and populated by tumor-associated macrophages, myeloid-derived suppressor cells, and regulatory T cells, ultimately inhibiting immune checkpoint inhibitors. Emerging fields such as glycomics and epigenetics, as well as stem cell biology, have defined promising biomarkers and targets. Preclinical studies have identified that glycan-directed CAR therapies could be possible, as well as metabolic inhibitors and 3D tumor models, which presented some preclinical success and could allow for tumoral specificity and enhanced efficacy. OS is a biologically and clinically complex disease; however, advances in exploring the molecular and immunologic landscape of OS present new opportunities in biomarkers and the development of new treatment options with adjunctive care. Successful treatments in the future will require personalized, multi-targeted approaches to account for tumor heterogeneity and immune evasion. This will help us turn the corner in providing improved outcomes for patients with this resilient malignancy. Full article

CD26 (dipeptidyl peptidase-4) is a marker of colorectal cancer stem cells with high metastatic potential and resistance to therapy. Although CD26 expression is known to be associated with tumor progression, its functional involvement in epithelial-mesenchymal transition (EMT) and metastasis remains to be fully elucidated. In this study, we aimed to investigate the effects of a monoclonal anti-CD26 antibody on EMT-related phenotypes and metastatic behavior in colorectal cancer cells. We evaluated changes in EMT markers by quantitative PCR and Western blotting, assessed cell motility and invasion using scratch wound-healing and Transwell assays, and examined metastatic potential in vivo using a splenic injection mouse model. Treatment with the anti-CD26 antibody significantly increased the expression of the epithelial marker E-cadherin and reduced levels of EMT-inducing transcription factors, including ZEB1, Twist1, and Snail1, at the mRNA and protein levels. Functional assays revealed that the antibody markedly inhibited cell migration and invasion in vitro without exerting cytotoxic effects. Furthermore, systemic administration of the anti-CD26 antibody significantly suppressed the formation of liver metastases in vivo. These findings suggest that CD26 may contribute to the regulation of EMT and metastatic behavior in colorectal cancer. Our data highlight the potential therapeutic utility of CD26-targeted antibody therapy for suppressing EMT-associated phenotypes and metastatic progression. Full article

Glioblastoma (GBM) is a highly aggressive brain tumor marked by invasive growth and therapy resistance. Tumor cells adapt to hostile conditions, such as hypoxia and nutrient deprivation, by activating survival mechanisms including autophagy and metabolic reprogramming. Among GBM-associated changes, hypersialylation, particularly, the aberrant expression of polysialic acid (PSA), has been linked to increased plasticity, motility, and immune evasion. PSA, a long α2,8-linked sialic acid polymer typically attached to the NCAM, is abundant in the embryonic brain and re-expressed in cancers, correlating with poor prognosis. Here, we investigated how PSA expression was regulated in GBM cells under nutrient-limiting conditions. Serum starvation induced a marked increase in PSA-NCAM, driven by upregulation of the polysialyltransferase ST8SiaIV and an autophagy-dependent recycling of sialic acids from degraded glycoproteins. Inhibition of autophagy or sialidases impaired PSA induction, and PSA regulation appeared dependent on p53 function. Immunohistochemical analysis of GBM tissues revealed co-localization of PSA and LC3, particularly around necrotic regions. In conclusion, we identified a novel mechanism by which GBM cells sustain PSA-NCAM expression via autophagy-mediated sialic acid recycling under nutrient stress. This pathway may enhance cell migration, immune escape, and stem-like properties, offering a potential therapeutic target in GBM. Full article

Chemoresistance is a major challenge in the treatment of triple-negative breast cancer (TNBC). Multicellular spheroids are an attractive platform for investigating chemoresistance in TNBC, as they replicate the cues of the tumour microenvironment in vivo. We conducted a comprehensive literature search to summarise the multifactorial and interlinked mechanisms driving chemoresistance in TNBC spheroids. These mechanisms include spatial heterogeneity, hypoxia, extracellular matrix remodelling, tumour–stroma crosstalk, drug efflux, apoptotic resistance, and cancer stem cell signalling. Strategies for overcoming chemoresistance in TNBC spheroids include nanocarrier systems to overcome spatial diffusion limitations, pathway inhibition, and targeting tumour–microenvironment interactions. Despite their advantages, some spheroid models face challenges such as low reproducibility, a lack of heterogeneity, variability in size and shape, limited vascularisation, and constraints in long-term culture. Advanced culturing platforms such as clinostat bioreactors allow for extended culture periods, enabling mature spheroid drug testing. Furthermore, advanced analytical techniques provide spatially resolved spheroid data. These multifactorial and interlinked mechanisms reflect the tumour microenvironment in vivo that spheroids recapitulate, rendering them valuable models for studying chemoresistance. The incorporation of stromal components and advanced analytical workflows will enhance the utility and translational relevance of spheroids as reliable preclinical models for drug discovery in TNBC. Full article

Background: Often, neoadjuvant therapy, which relies on the induction of double-strand breaks (DSBs), is used prior to surgery to shrink tumors by inducing cancer cell apoptosis. However, recent studies have suggested that this treatment may also induce a fluctuating state between senescence and stemness in PA-1 embryonal carcinoma cells, potentially affecting therapeutic outcomes. Thus, the respective epigenetic pathways are up or downregulated over a time period of days. These fluctuations go hand in hand with changes in spatial DNA organization. Methods: By means of Single-Molecule Localization Microscopy in combination with mathematical evaluation tools for pointillist data sets, we investigated the organization of euchromatin and heterochromatin at the nanoscale on the third and fifth day after etoposide treatment. Results: Using fluorescently labeled antibodies against H3K9me3 (heterochromatin tri-methylation sites) and H3K4me3 (euchromatin tri-methylation sites), we found that the induction of DSBs led to the de-condensation of heterochromatin and compaction of euchromatin, with a peak effect on day 3 after the treatment. On day 3, we also observed the co-localization of euchromatin and heterochromatin, which have marks that usually occur in exclusive low-overlapping network-like compartments. The evaluation of the SMLM data using topological tools (persistent homology and persistent imaging) and principal component analysis, as well as the confocal microscopy analysis of H3K9me3- and H3K4me3-stained PA-1 cells, supported the findings that distinct shifts in euchromatin and heterochromatin organization took place in a subpopulation of these cells during the days after the treatment. Furthermore, by means of flow cytometry, it was shown that the rearrangements in chromatin organization coincided with the simultaneous upregulation of the stemness promotors OCT4A and SOX2 and senescence promotors p21Cip1 and p27. Conclusions: Our findings suggest potential applications to improve cancer therapy by inhibiting chromatin remodeling and preventing therapy-induced senescence. Full article

Background: Cucurbitacin E (CuE), a natural tetracyclic triterpenoid compound extracted from the melon stems of Cucurbitaceae plants, has been reported to exhibit anti-inflammatory and anti-cancer properties, along with the ability to enhance cellular immunity. However, its role and molecular mechanism in regulating lipid metabolism and adipogenesis remain unclear. This study aims to investigate the potential anti-adipogenic and anti-obesity effects of CuE in 3T3-L1 adipocytes. Materials and Methods: 3T3-L1 preadipocytes were cultured and induced to differentiate using a standard adipogenic cocktail containing dexamethasone, 3-isobutyl-1-methylxanthine (IBMX), and insulin (DMI). CuE was administered during the differentiation process at various concentrations. Lipid accumulation was assessed using Oil Red O staining, and cell viability was evaluated via the MTT assay. To determine whether CuE induced apoptosis or necrosis, flow cytometry was performed using annexin V/PI staining. Additional molecular analyses, such as Western blotting and RT-PCR, were used to examine the expression of key adipogenic markers. Results: Treatment with CuE significantly reduced lipid droplet formation in DMI-induced 3T3-L1 adipocytes in a dose-dependent manner, as shown by decreased Oil Red O staining. Importantly, CuE did not induce apoptosis or necrosis in 3T3-L1 cells at effective concentrations, indicating its safety toward normal adipocytes. Moreover, CuE treatment downregulated the expression of adipogenic markers such as PPARγ and C/EBPα at both mRNA and protein levels. Discussion: Our findings suggest that CuE exerts a non-cytotoxic inhibitory effect on adipocyte differentiation and lipid accumulation. This anti-adipogenic effect is likely mediated through the suppression of key transcription factors involved in adipogenesis. The absence of cytotoxicity supports the potential application of CuE as a safe bioactive compound for obesity management. Further investigation is warranted to elucidate the upstream signaling pathways and in vivo efficacy of CuE. Conclusions: Cucurbitacin E effectively inhibits adipogenesis in 3T3-L1 adipocytes without inducing cytotoxic effects, making it a promising candidate for the development of functional foods or therapeutic agents aimed at preventing or treating obesity. This study provides new insights into the molecular basis of CuE’s anti-obesity action and highlights its potential as a natural lipogenesis inhibitor. Full article

Tumor drug resistance, a major cause of treatment failure, involves complex multi-gene networks, remodeling of signaling pathways, and interactions with the tumor microenvironment. Yin Yang 1 (YY1) is a critical oncogene overexpressed in many tumors and mediates multiple tumor-related processes, such as cell proliferation, metabolic reprogramming, immune evasion, and drug resistance. Notably, YY1 drives resistance through multiple mechanisms, such as upregulation of drug efflux, maintenance of cancer stemness, enhancement of DNA repair capacity, modulation of the tumor microenvironment, and epithelial–mesenchymal transition, thereby positioning it as a pivotal regulator of drug resistance. This review examines the pivotal role of YY1 in resistance, elucidating its molecular mechanisms and clinical relevance. We demonstrate that YY1 inhibition could effectively reverse drug resistance and restore therapeutic sensitivity across various treatment modalities. Importantly, we highlight the promising potential of YY1-targeted strategies, particularly combined with anti-tumor agents, to overcome resistance barriers. Furthermore, we discuss critical translational considerations for advancing these combinatorial approaches into clinical practice. Full article

Origanum majorana L. (O. majorana) (Lamiaceae) is an aromatic Mediterranean plant widely used in food, cosmetics, and traditional medicine due to its aroma and rich content of bioactive compounds. While its leaves and flowers are commonly utilized, lignified stems are often discarded. This study compared hydroalcoholic extracts from the leaves and flowers (valuable fraction, VF) and stems (by-product, BP). Phytochemical analysis revealed qualitatively similar profiles, identifying 20 phenolic compounds, with Rosmarinic acid and Salvianolic acid B as the most and second most abundant, respectively. Antioxidant activity was evaluated in vitro using DPPH (IC₅₀ [µg/mL]: VF 30.11 ± 3.46; BP 31.72 ± 1.46), H₂O₂ (IC₅₀ [µg/mL]: VF 103.09 ± 4.97; BP 119.55 ± 10.58), and O₂^•− (IC₅₀ [µg/mL]: VF 0.71 ± 0.062; BP 0.79 ± 0.070). Both extracts (20 µg/mL) fully restored oxidative balance in hemin-stressed AC16 cardiomyocytes, without altering the expression of catalase, heme-oxygenase 1, superoxide dismutase 2, or ferritin. Anti-inflammatory activity in LPS-stimulated RAW 264.7 macrophages showed that VF (IC₅₀ 400 µg/mL) reduced ^•NO release to control levels, while BP achieved a ~60% reduction. Cytotoxicity was assessed on cancer cell lines: CaCo-2 (IC₅₀ [µg/mL]: VF 154.1 ± 6.22; BP 305.2 ± 15.94), MCF-7 (IC₅₀ [µg/mL]: VF 624.6 ± 10.27; BP 917.9 ± 9.87), and A549 (IC₅₀ [µg/mL]: VF 720.8 ± 13.66; BP 920.2 ± 16.79), with no cytotoxicity on normal fibroblasts HFF-1 (IC₅₀ > 1000 µg/mL for both extracts). Finally, both extracts slightly inhibited only CYP1A2 (IC₅₀ [µg/mL]: VF 497.45 ± 9.64; BP 719.72 ± 11.37) and CYP2D6 (IC₅₀ [µg/mL]: VF 637.15 ± 14.78, BP 588.70 ± 11.01). These results support the potential reuse of O. majorana stems as a sustainable source of bioactive compounds for nutraceutical and health-related applications. Full article

Background/Objectives: Cisplatin remains a cornerstone chemotherapeutic agent for non-small-cell lung cancer (NSCLC) treatment, yet its clinical utility is substantially limited by acquired resistance and the inadequate suppression of tumor metastasis. Emerging evidence implicates interleukin 6 (IL-6) as a critical mediator of chemoresistance through cancer stem cell (CSC) enrichment and metastasis promotion via epithelial–mesenchymal transition (EMT) induction, ultimately contributing to cisplatin therapy failure. This study sought to address these challenges by designing a nanoplatform with two innovative aims: (1) to achieve active tumor targeting through binding to the IL-6 receptor (IL-6R), and (2) to concurrently inhibit IL-6-mediated chemoresistance signaling pathways. Methods: A lipid–polymer hybrid nanoparticle (LPC) encapsulating cisplatin was synthesized and subsequently surface-functionalized with tocilizumab (TCZ), a monoclonal antibody that targets IL-6R. The therapeutic efficacy of this TCZ-modified nanoparticle (LPC-TCZ) was assessed through a series of in vitro and in vivo experiments, focusing on the inhibition of EMT, expression of CSC markers, tumor growth, and metastasis. Results: Systematic in vitro and in vivo evaluations revealed that LPC-TCZ synergistically attenuated both EMT progression and CSC marker expression through the targeted blockade of IL-6/STAT3 signaling. This multimodal therapeutic strategy demonstrated superior tumor growth inhibition and metastatic suppression compared to conventional cisplatin monotherapy. Conclusions: Our findings establish a nanotechnology-enabled approach to potentiate cisplatin efficacy by simultaneously countering chemoresistance mechanisms and metastatic pathways in NSCLC management. Full article

Background: Protein arginine methyltransferase 3 (PRMT3), a type I family PRMT, regulates the activity of downstream substrates by catalyzing the asymmetric dimethylation of arginine residues. While PRMT3 activity has been reported to be deregulated in many cancers, including glioblastoma (GBM), the underlying signalling mechanisms that contribute to disease progression are largely unknown. Methods: We tested the efficacy of a PRMT3 chemical probe, SGC707, in a cohort of GBM patient-derived primary and recurrent brain tumour stem cell (BTSC) lines. RNA-sequencing, CRISPR-cas9 knockout, and inducible overexpression methods were used to investigate the molecular mechanisms regulated by the aberrant activity of PRMT3 in different BTSC lines. Results: We show that expression of the tumour suppressor protein 4.1B, a negative regulator of PRMT3, predicts the response of GBM BTSCs to the PRMT3 chemical probe, SGC707. Furthermore, PRMT3 modulates the stability and subcellular localization of the downstream effector, UHRF1, a member of the DNA methylation complex. These findings suggest that UHRF1 and DNMT1 may suppress the expression of 4.1B through the increased promoter methylation of EPB4.1L3. Intriguingly, the inducible overexpression of EPB4.1L3 in the BT248^EPB4.1L3low BTSC line mimicked the effects of the pharmacologic and genetic inhibition of PRMT3. In contrast, knockout of EPB4.1L3 in BT143^EPB4.1L3high cells reduced the interactions between PRMT3 and 4.1B proteins, resulting in increased sensitivity of knockout cells to SGC707 treatment. Conclusions: These findings show that 4.1B, PRMT3, and UHRF1/DNMT1 function together to promote BTSC growth. Thus, targeting PRMT3 or UHRF1/DNMT1, especially in tumours with low endogenous 4.1B protein, may have high therapeutic relevance. Full article

Anaplastic thyroid carcinoma (ATC) is a highly aggressive malignancy with poor prognosis and limited treatment options. Precision oncology seeks personalized therapies that selectively modulate tumor behavior, which is critical for improving patient outcomes. In this study, we evaluated the therapeutic potential of human dental pulp stem cell-derived extracellular vesicles (hDPSC-EVs) in three ATC cell lines (8505C, HTH83, KTC-2). Fluorescence and confocal microscopy confirmed the efficient, time-dependent internalization of hDPSC-EVs by ATC cells, with increased fluorescence intensity over 48 h. Functional assays revealed the selective inhibition of migration and invasion in a cell line-dependent manner, without affecting cell proliferation, viability, or tumorigenic traits, indicating a non-cytotoxic, context-specific modulation of tumor behavior. After 72 h of EV treatment, targeted qPCR of 92 cancer-related genes showed the strongest response in 8505C cells (24 genes; 16 up, 8 down), moderate changes in KTC-2 (16 genes; 14 up, 2 down), and few alterations in HTH83 (6 genes; 4 up, 2 down). Across all lines, FN1 emerged as a context-dependent target, downregulated in 8505C but upregulated in the other two. No broad pathway enrichment was observed, indicating the fine-tuning of key networks rather than wholesale reprogramming. Despite variations across cell lines, hDPSC-EVs consistently demonstrated no impact on cell proliferation and no evidence of cytotoxicity or tumorigenic behavior, with no adverse outcomes. These findings provide preclinical evidence for hDPSC-EVs as a promising, safe, and targeted therapeutic platform in precision oncology, particularly for aggressive cancers, like ATC, warranting further exploration in preclinical and clinical studies. Full article

Eukaryotic cells double their mass and divide at the same rate, allowing cells to maintain a uniform cell size over many cell divisions. We hypothesize that aneuploid cancer cells are more sensitive to forced overgrowth, more than doubling their mass during a single longer-duration cell division cycle, relative to healthy diploid cells. This hypothesis stems from the observation that cancer cells are under proteotoxic stress, during which heat-shock proteins become rate-limiting and the unfolded-protein response network has a growth-suppressive phenotype. Forced overgrowth will lead to the production of more individual proteins per cell division cycle and increase the duration of time during which any mis-folded or aggregated proteins might disrupt the function of properly folded proteins. To induce these potential forced overgrowth effects, we suggest targeting the cell division cycle regulatory enzyme, the anaphase-promoting complex/cyclosome (APC/C), to suppress—but not inhibit—its activity. We conclude by proposing experiments to test this hypothesis in which an APC/C inhibitor, such as a low level of proTAME, is combined with the clinically approved heat-shock protein 90 (HSP90)-inhibitor pimitespib (TAS-116) or the pre-clinical molecule tanespimycin, which, to the best of our knowledge, are combinations that have not been investigated before. Full article

Triple-negative breast cancer (TNBC), characterized by the absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), remains a therapeutic challenge due to its aggressive nature, limited treatment options, and high recurrence rates. Current therapies, including chemotherapy and immune checkpoint inhibitors, face resistance driven by tumor heterogeneity, immunosuppressive signaling, and dysregulated redox pathways. This review explores silibinin’s potential to modulate the tumor immune microenvironment (TIME) and overcome therapeutic resistance in TNBC. Silibinin exerts multifaceted anticancer effects by suppressing PD-L1 expression through the inhibition of JAK/STAT3 signaling and MUC1-C interaction, attenuating NF-κB-driven inflammation, and downregulating CCL2-mediated recruitment of tumor-associated macrophages (TAMs). Additionally, silibinin disrupts redox adaptation by targeting the Nrf2-EGFR-MYC-TXNIP axis, enhancing oxidative stress and chemosensitivity. Preclinical studies highlight its ability to inhibit epithelial–mesenchymal transition (EMT), reduce cancer stem cell (CSC) populations, and synergize with existing therapies like PD-1 inhibitors. Despite its low bioavailability, advanced formulations such as liposomes and nanoparticles show promise in improving delivery and efficacy. By reshaping TIME through dual antioxidant and immunomodulatory mechanisms, silibinin emerges as a viable adjunct therapy to reverse immunosuppression and chemoresistance in TNBC. Full article

Mesenchymal stem cells (MSCs) have recently shown great promise as potential anticancer drug delivery carriers. MSCs exhibit tropism to inflammatory sites, such as tumor beds, and resistance to chemotherapeutics. The aim of this study was to examine the efficacy of gemcitabine (GEM) conjugated with flurbiprofen (FLU) as a potential agent enhancing the GEM cytotoxic effect. Pancreatic cancer cell lines (PCCs), including PANC-1, AsPC-1, and BxPC-3, were studied meticulously. Moreover, the usefulness of bone-marrow-derived mesenchymal stem cells (BM-MSCs) treated with GEM and FLU, and the conditioned media from above these cells (CM) as elements supporting the in vitro action of GEM, inducing apoptosis, necrosis, and inhibiting the cell cycle, was tested. The results showed that CM-GEM exhibited higher cytotoxicity towards the selected PCCs compared to GEM alone. Furthermore, the obtained data revealed lower sensitivity of these cells to treatment, which promotes the utilization of BM-MSCs as potential drug carriers. Based on the presented findings, it seems that applying FLU in the antiproliferative effect of GEM might be regarded as an effective strategy in the therapy of pancreatic cancer, especially in the inhibition of proliferation and induction of cancer cell death. Full article

Bardoxolone methyl, also known as CDDO-Me or RTA 402, is a synthetic oleanane triterpenoid that has garnered significant attention as a potent pharmacological activator of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Nrf2 is a master regulator of cellular redox homeostasis, controlling the expression of genes involved in antioxidant defense, detoxification, and mitochondrial function. By inducing Nrf2 and promoting the transcription of downstream antioxidant response element (ARE)-driven genes, bardoxolone methyl enhances cellular resilience to oxidative stress and inflammation. This mechanism is central not only to its cytoprotective effects but also to its emerging role in oncology. A number of studies investigated the effects of bardoxolone methyl in several malignancies including breast cancer, lung cancer, pancreatic ductal adenocarcinoma, prostate cancer, colorectal cancer, oral and esophageal squamous cell carcinoma, ovarian cancer and glioblastoma. Studies in the literature indicate that bardoxolone methyl exhibits anticancer activity through several mechanisms, including the suppression of cell proliferation, induction of cell cycle arrest and apoptosis, inhibition of epithelial–mesenchymal transition (EMT), and impairment of cancer cell stemness. Additionally, bardoxolone methyl modulates mitochondrial function, reduces glycolytic and oxidative phosphorylation capacities, and induces reactive oxygen species (ROS)-mediated stress responses. In this review, we summarize the available literature regarding the studies which investigated the effects of bardoxolone methyl as anticancer agent. Full article