Search Results (4,653)

Background/Objectives: Epithelial ovarian cancer (EOC) is often diagnosed at advanced stages, with metastasis driven by spheroid dissemination within the peritoneal cavity. We previously demonstrated that autophagy supports spheroid cell survival and suggest that it contributes to chemoresistance. Unc-51-like autophagy activating kinase 1 (ULK1), a key regulator of autophagy, has emerged as a promising therapeutic target. Here, we evaluated the effects of ULK1 inhibition via MRT68921, alone and in combination with afatinib—a tyrosine kinase inhibitor (TKI) known to induce pro-survival autophagy—in EOC. Methods: High-grade serous (HGSOC) and ovarian clear cell carcinoma (OCCC) cell lines were cultured under adherent and spheroid conditions. Immunoblotting confirmed on-target effects and modulation of autophagy. Autophagic flux was assessed using mCherry-eGFP-LC3 reporter assays. We assessed 96 dose combinations of MRT68921 and afatinib using drug combination matrices, with synergy evaluated via Synergy Finder. Promising combinations were evaluated across multiple EOC spheroid models and patient ascites-derived organoids. Results: MRT68921 inhibited ULK1 activity and reduced autophagic flux in a context-dependent manner while afatinib alone induced autophagy. Their combination produced synergistic effects at select concentrations, impairing spheroid reattachment and viability. However, MRT68921 alone significantly reduced viability across multiple EOC models, including patient ascites-derived organoids. Conclusions: This study is the first to evaluate the combined effects of MRT68921 and afatinib in epithelial ovarian cancer. Our findings demonstrate that ULK1 inhibition via MRT68921 consistently reduces cell viability across multiple ovarian cancer models, supporting ULK1 as a promising therapeutic target. In contrast, combination with afatinib produced limited and context-dependent effects, indicating that further investigation is needed to identify optimal combination strategies for ULK1-targeted therapies. Full article

Among the metal-derived complexes, recently, tin derivatives have been investigated as promising anti-cancer drug candidates. Our previous study showed that the tin-based compound Bu₃SnOCOCF₃ (TBT) exerts cytotoxic activity on solid tumor cell lines. In the present study, the effects of TBT were evaluated in vitro on HTLV-1-infected human lymphocytic cell lines at different stages of viral transformation, consisting of IL-2-dependent (PB2/IL-2) and IL-2-independent (PB2/NO-IL-2) cells, generated in our laboratory by HTLV-1 in vitro infection of lymphocytes from the same donor, and the C91/PL cell line established by co-cultivation with T cells from a patient with HTLV-1-positive leukemia. TBT induced a reliable and reproducible dose-dependent inhibition of metabolic activity and viability in the HTLV-1-infected cells. The effect was cell-type-dependent, with C91/PL cells being quite resistant. An investigation into the cytotoxic effects induced by TBT in HTLV-1-infected cells and data on caspase inhibitors/caspase activation indicated that apoptotic cell death was involved, but also that the possible involvement of other forms of cell death could not be excluded. Taken together, the results show for the first time that the tin-based compound, although not devoid of a certain cytotoxicity toward uninfected cells, can induce typical and potent effects on HTLV-1-infected cells. Full article

Breast cancer is a significant cause of death worldwide. Recent research has focused on identifying natural compounds for developing effective cancer treatments. Resiniferatoxin, a transient receptor potential vanilloid 1 (TRPV1) agonist, is a common diterpene in Euphorbia bicolor Engelm. & A. Gray (Euphorbiaceae), a plant native to the southern United States that has not been studied before. We investigated the antiproliferative activities and mechanisms of action of E. bicolor xylene extract in estrogen receptor-positive T47D and triple-negative MDA-MB-231 cell lines. The extract significantly reduced the viability of T47D and MDA-MB-231 cells in a dose-dependent manner. In MDA-MB-231 cells, the extract induced apoptosis via intracellular calcium overload, triggered by TRPV1 activation. This effect was diminished by the TRPV1 antagonist capsazepine and the calcium chelator BAPTA-AM. Intracellular calcium influx was confirmed through Fura-2 AM staining, revealing that E. bicolor phytochemicals activated TRPV1 in MDA-MB-231 cells. Treatment of T47D cells with E. bicolor xylene extract resulted in apoptosis associated with reactive oxygen species (ROS) generation (10-fold higher in T47D cells than in MDA-MB-231 cells) and mitochondrial calcium overload. These effects were significantly blocked when cells were pretreated with N-acetyl-l-cysteine (NAC), a ROS inhibitor. Both cell lines underwent apoptosis via multiple mitochondrial- and endoplasmic reticulum stress–mediated pathways. This was supported by the activation of caspases 3, 8, and 9; increased expression of FAS, XBP1s, and CHOP; upregulation of BAX; and downregulation of BCL-2. In addition, PI3K, AKT, and pAKT protein expressions were also reduced in both cell lines, indicating downregulation of PI3K/Akt signaling pathway. Phytochemicals in E. bicolor xylene extract could become promising ingredients for developing breast cancer therapeutics. Full article

Chimeric antigen receptor (CAR) T cell therapy has demonstrated clinical success in hematologic malignancies but has limited efficacy in solid tumors due to tumor microenvironment (TME) barriers that impede CAR T cell recognition, infiltration, and sustained function. Traditional 2D assays inadequately recapitulate these constraints, necessitating improved in vitro models. This study validated a 3D tumor spheroid platform using an agarose microwell system to generate uniform B7-H3-positive spheroids from multiple solid tumor cell lines, enabling the evaluation of CAR T cell activity. TME-relevant immune modulation under 3D conditions was analyzed by flow cytometry for B7-H3, MHC I/II, and antigen processing machinery (APM), followed by co-culture with B7-H3 CAR T cells to assess cytotoxicity, spheroid integrity, tumor viability, and CAR T cell activation, exhaustion, and cytokine production. Two human cancer-cell-line-derived spheroids, DU 145 (prostate cancer) and SUM159 (breast cancer), retained B7-H3 expression, while MC38 (mouse colon cancer)-derived spheroids served as a B7-H3 negative control. Under 3D culture conditions, DU 145 and SUM159 spheroids acquire TME-like immune evasion characteristics and specifically downregulated MHC-I and APM (TAP1, TAP2, LMP7) with concurrent upregulation of MHC-II and calreticulin. Co-culture showed effective spheroid infiltration, cytotoxicity, and structural disruption, with infiltrating CAR T cells displaying higher CD4⁺ fraction, activation, exhaustion, effector/terminal differentiation, and IFN-γ/TNF-α production. This 3D platform recapitulates critical TME constraints and provides a cost-effective, feasible preclinical tool to assess CAR T therapies beyond conventional 2D assays. Full article

Two series of tri(2-furyl)- and triphenylphosphine-gold(I) complexes, with pyridyl- and pyrimidine-thiolate ligands containing electron-donating (-CH₃) and electron-withdrawing (-CF₃) substituents were synthesized and investigated for cell viability inhibitions. Prior results indicate that several of the gold(I) complexes in these series have high antifungal properties. The observed link between antifungal and anticancer activity provided motivation to investigate their antiproliferative effects, reported here. The synthesized compounds from both series were characterized by ¹H, ¹³C, and ³¹P NMR spectroscopy, mass spectrometry (MS), infrared and UV-Vis spectroscopy, and solution stability studies. In addition, an X-ray crystallographic study was conducted on one of the gold(I) complexes. Analyte solubilities in McCoy’s 5A cell media were evaluated by ICP-MS. Initial screening studies were conducted on the two series to evaluate cell viability using the SK-BR-3 cell line. All ten gold(I) complexes exhibited sub-µM cytotoxicity and the most potent representatives, one from each series, were selected for further evaluation in four additional cell lines. Half-maximal effective concentrations (EC₅₀) were determined for the MCF7 and MDA-MB-231 malignant mammary cell lines as well as the two control cell lines, HEK293T and MCF10A, to probe for specificity. Results indicate significant selectivity towards inhibition of cancer cells compared to non-transformed for tri(2-furyl)- and triphenylphosphine-gold(I) complexes with the 3,5-dimethylpyrimidine thiolate ligand when dissolved in cell media. Additional studies including 1% DMSO as a solubilizing agent revealed its significant impact on cellular responses. Full article

Near-infrared photoimmunotherapy (NIR-PIT) has recently attracted attention as a highly selective cancer treatment, with good treatment outcomes observed from the only antibody-based drug currently available for clinical use. However, since only a single agent is currently used clinically and the development of new antibodies is costly, exploring other therapeutic modalities is important. In this study, we investigated a novel peptide-based PIT drug targeting programmed death-ligand 1 (PD-L1), which is overexpressed in many types of cancer. The WL12 peptide, which is known to bind to PD-L1, was conjugated with the photoabsorber IRDye700DX (IR700), and its usefulness was evaluated in vitro and in vivo. In therapeutic experiments on PD-L1-positive cells, NIR-PIT with WL12-IR700 induced PIT-like morphological changes in cells and reduced cancer cell viability in an NIR light dose- and drug concentration-dependent manner. In vivo experiments showed significant suppression of tumor growth and an extended overall survival rate. These results indicate that the developed peptide-based drug can be used for PD-L1-targeted NIR-PIT. Full article

Background/Objectives: Cancer-associated fibroblasts (CAFs) are key stromal mediators of breast tumor progression and therapy resistance. Carvacrol, a dietary monoterpenic phenol, exhibits antiproliferative activity in cancer cells, but its effects on primary human breast CAFs remain unclear. This study aimed to determine whether carvacrol selectively induces mitochondria-related apoptotic signaling in breast CAFs while sparing normal fibroblasts (NFs). Methods: Primary fibroblast cultures were established from invasive ductal carcinoma tissues (CAFs, n = 9) and nonmalignant breast tissues (NFs, n = 5) and validated by α-SMA and FAP immunofluorescence. Cells were exposed to 400 μM carvacrol. Apoptosis was assessed by TUNEL assay and BAX/BCL-XL Western blotting. Changes in signaling pathways were evaluated by analyzing PPARα/NF-κB, sirtuin (SIRT1, SIRT3), autophagy-related markers (LAMP2A, p62), and matrix metalloproteinases (MMP-2, MMP-3). In silico molecular docking and 100-ns molecular dynamics simulations were performed to examine interactions between carvacrol and caspase-3 and caspase-9. Results: Carvacrol induced a pronounced, time-dependent apoptotic response in CAFs, with TUNEL-based viability declining to approximately 10% of control levels by 12 h and a marked increase in the BAX/BCL-XL ratio. In contrast, NFs exhibited minimal TUNEL positivity and no significant change in BAX/BCL-XL. In CAFs, but not NFs, carvacrol reduced PPARα expression and NF-κB nuclear localization, increased SIRT1 and SIRT3 levels, selectively suppressed MMP-3 while partially normalizing MMP-2, and altered autophagy-related markers (decreased LAMP2A and accumulation of p62), consistent with autophagic stress and possible impairment of autophagic flux. Computational analyses revealed stable carvacrol binding to caspase-3 and caspase-9 with modest stabilization of active-site loops, supporting caspase-dependent, mitochondria-related apoptosis. Conclusions: Carvacrol selectively targets breast cancer-associated fibroblasts by inducing mitochondria-related apoptotic signaling while largely sparing normal fibroblasts. This effect is accompanied by coordinated modulation of PPARα/NF-κB, sirtuin, autophagy, and MMP pathways. These findings support further evaluation of carvacrol as a microenvironment-directed adjunct in breast cancer therapy. Full article

Ponicidin, a bioactive diterpenoid derived from Rabdosia rubescens, has been shown to exhibit antitumor activity across a range of cancer types. Despite its potential therapeutic applications, the precise effects and underlying molecular mechanisms of ponicidin in the context of lung cancer remain insufficiently characterized. This study aims to investigate the antitumor effects of ponicidin in lung cancer, focusing on its impact on cell growth and cellular oxidative stress. Our findings demonstrate that ponicidin significantly inhibits the viability of lung cancer cells while exhibiting minimal cytotoxicity to normal lung cells. Notably, ponicidin induces cell death in lung cancer cells via the induction of oxidative stress, a process likely mediated by the depletion of sulfhydryl antioxidants and the downregulation of thioredoxin reductase (TrxR), both of which play critical roles in maintaining cellular redox homeostasis. Moreover, ponicidin was found to concurrently activate endoplasmic reticulum stress, induce mitochondrial dysfunction, and promote DNA damage, further contributing to its antitumor effects. In vivo, the efficacy of ponicidin was confirmed in tumor-bearing mouse models, where ponicidin treatment led to a significant reduction in tumor growth without significant toxicity or adverse effects on the animals. These findings suggest that ponicidin holds significant promise as a safe and effective therapeutic agent for lung cancer, warranting further investigation into its clinical applicability. Full article

Background: Many inhibitors have been discovered to target hypoxia-induced carbonic anhydrase IX (CAIX) due to its critical role in lung cancers. This study discovers a novel compound, 3-(E-3,4-dihydroxycinnamaoyloxyl)-2-hydroxypropyl-9Z,12Z-octadeca-9,12-dienoate, which is produced by the seagrass Cymodocea serrulata and has binding sites at CAIX that are distinct from those of current inhibitors. Methods: Compound and reference drug treatment for cell lines; Cell viability: MTT; Staining: Ao/PI/DAPI; MMP shifts and cell cycle: FACS; Gene and protein expression of CAIX, BAX, BAD: qPCR and Western blotting. Results: The compound binds to the CAIX protein, raises extracellular pH, and kills A549 cells [IC₅₀: 11.61 µM], producing results that are lower than those of the reference drug doxorubicin [13.7 µM]. The substance depolarised the electrical potential of the mitochondrial membrane, caused S-phase arrest, and fragmented DNA. Additionally, it downregulated CAIX by 0.9 times while increasing apoptotic mRNA, BAX and BAD by 5.2 and 3.08 times, respectively, as demonstrated by qPCR. Between 0 and 24 h, the untreated hypoxic cells had a ΔpHe of 0.15, but the compound-treated cells had a ΔpHe of 0.6 indicative of intracellular acidosis. MD simulations verify the stability of the CAIX–C1 complex for more than 100 ns, and in silico studies show a strong binding affinity of the molecule to CAIX [−7.55 kcal/mol]. Conclusions: This implies that the amount of extracellular alkalosis was increased by the combination of treatment and hypoxia induction. As a result, when the cells were deprived of O₂, the compound provided less defense against ROS. The compound binds to the glutamine and alanine amino acids at positions 242 and 392, respectively, at the central Zn atom of CAIX, which sets it apart from conventional sulphonamide CAIX inhibitors. This naturally occurring compound may be a potent CAIX inhibitor with newer binding sites, which could help treat hypoxic lung cancers. Full article

Lung cancer remains a major clinical challenge, with therapy resistance in non-small-cell lung cancer (NSCLC) driving the search for novel selective agents. This study demonstrates that 2,3′-dihydroxy-5′-methoxystilbene exhibits significant anticancer activity in NSCLC cell lines (A549, H23, and H460) while displaying substantially lower toxicity toward normal NIH/3T3 fibroblasts. The compound reduced the viability of H23 and H460 cells after 48 h. (IC50: 23.39 ± 3.27 μM and 24.20 ± 2.61 μM, respectively), with NIH/3T3 cells remaining comparatively resistant (IC50 > 100 μM). At 25 μM, it suppressed proliferation by approximately 40% in H23, 30% in H460, and 20% in A549 cells, and dose-dependently impaired colony formation and migration, leading to near-complete migration arrest in H460 cells. Apoptosis induction peaked at 19% in H23, 17% in H460, and 8% in A549 cells at 25 μM. Mechanistic studies and molecular modeling revealed AKT-dependent activity, with decreased p-AKT and p-GSK3β levels (0.70 and 0.75 in H23; 0.65 and 0.70 in H460 at 25 μM), without changes in total protein expression. Combination treatment with cisplatin yielded synergistic effects in A549 (CI = 0.83) and H460 (CI = 0.94) cells, but antagonistic effects in H23 cells (CI = 1.32). These findings identify 2,3′-dihydroxy-5′-methoxystilbene as a selective AKT-targeting stilbene with promising anticancer potential and context-dependent chemosensitizing activity in NSCLC cells. Full article

Quercetin (Q), a bioactive flavonoid, exerts potent antioxidant and redox-modulating effects by activating the nuclear factor erythroid 2-related factor 2/antioxidant response Element (Nrf2/ARE) pathway and upregulating endogenous antioxidant defenses, including enzymatic antioxidants such as superoxide dismutase (SOD) and catalase (CAT), as well as non-enzymatic glutathione (GSH) and lipid peroxidation (MDA). Gemcitabine (Gem), a widely used antimetabolite chemotherapeutic, often shows limited efficacy under hypoxic and oxidative stress conditions driven by hypoxia-inducible factor 1-alpha (HIF-1α) and vascular endothelial growth factor (VEGF)-mediated angiogenesis. This study investigated the redox-mediated synergistic effects of Q and Gem in MDA-MB-231 human breast cancer cells. Combination treatment significantly reduced cell viability beyond the expected Bliss value, indicating a synergistic interaction and enhanced apoptosis compared with single-agent treatments. Increased reactive oxygen species (ROS) production was accompanied by depletion of GSH and accumulation of MDA, establishing a pro-apoptotic oxidative stress environment. Q alone enhanced SOD and CAT activities, whereas the combination induced exhaustion of antioxidant defenses under oxidative load, reflecting a redox-adaptive response. Molecular analyses revealed downregulation of HIF-1α and VEGF, alongside upregulation of Bax and Caspase-3, confirming suppression of hypoxia-driven survival and activation of the intrinsic apoptotic pathway. Transcriptomic and enrichment analyses further identified modulation of oxidative stress- and apoptosis-related pathways, including phosphoinositide-3-kinase–protein kinase B/Akt (PI3K/Akt), HIF-1 and VEGF signaling. Collectively, these results indicate that Q potentiates Gem cytotoxicity via redox modulation, promoting controlled ROS elevation and apoptosis while suppressing hypoxia-induced survival mechanisms, highlighting the therapeutic potential of redox-based combination strategies against chemoresistant breast cancer. Full article

Estrogen (E2, 17β estradiol) is recognized for its regulatory role in numerous genes associated with energy metabolism and for its ability to disrupt mitochondrial function in various cancer types. However, the influence of E2 on the metabolism of colorectal cancer (CRC) cells remains largely unexplored. In this study, we examined how E2 affects mitochondrial function and energy production in CRC cells, utilizing two distinct CRC cell lines, HCT-116 and SW480. Cell viability, mitochondrial function, and the expression of several genes involved in oxidative phosphorylation (OXPHOS) were assessed in estrogen receptor α (ERα)-expressing and ERα-silenced cells treated with increasing concentrations of E2 for 48 h. Our results indicated that the cytotoxicity of E2 against CRC cells is mediated by the E2/ERα complex, which induces disturbances in mitochondrial function and the OXPHOS pathway. Furthermore, we identified two novel targets, RPS2 and TMEM177, which displayed overexpression, hypomethylation, and a negative association with ERα expression in CRC tissue. E2 treatment in CRC cells reduced the expression of both targets through promoter hypermethylation. Treatment with 5-Aza-2-deoxycytidine increased the expression of RPS2 and TMEM177. This epigenetic effect disrupts the mitochondrial membrane potential (MMP), resulting in decreased activity of the OXPHOS pathway and inhibition of CRC cell growth. Knockdown of RPS2 or TMEM177 in CRC cells resulted in anti-cancer effects and disruption of MMP and OXPHOS. These findings suggest that E2 exerts ERα-dependent epigenetic reprogramming that leads to significant mitochondria-related anti-growth effects in CRC. Full article

Carvacrol, a phenolic monoterpene predominantly found in Origanum species, has been reported to exhibit antimicrobial, anti-inflammatory, antioxidant, and cytotoxic effects. Formulations such as Vacrol and S-Mix, enriched with carvacrol and complementary essential oil compounds, may enhance therapeutic efficacy while reducing toxicity. Essential oil components were analyzed via GC-MS. Cell viability was assessed using the sulforhodamine B (SRB) assay at different concentrations and incubation periods. An in ovo chorioallantoic membrane (CAM) assay was performed to investigate tumor volume changes and histopathological alterations. Vacrol and S-Mix demonstrated concentration- and time-dependent cell viability-attenuating effects in MDA-MB-231 cells, with significant reductions in viability at higher concentrations (1–10 mM). In ovo, S-Mix induced ~40% reduction in tumor volume and promoted apoptotic morphology compared to controls. Combined effects of carvacrol with α-pinene, eugenol, and β-terpineol likely contributed to enhanced bioactivity. These findings support further preclinical and mechanistic investigations to validate their therapeutic potential. Full article

Background/Objectives: Oral squamous cell carcinoma (OSCC) remains a major therapeutic challenge due to treatment-related toxicity and impaired oral tissue regeneration. This study aimed to develop and characterize a novel biocomposite based on bioactive compounds from Ganoderma lucidum incorporated into marine collagen derived from Rhizostoma pulmo and to evaluate its physicochemical properties, antioxidant and antimicrobial activities, and in vitro antitumor potential in the oral cavity. Methods: Hydroalcoholic extracts of G. lucidum and pepsin-soluble collagen peptides from R. pulmo jellyfish were prepared and combined to obtain two hydrogel biocomposites with different component ratios. Chemical and structural characterization was performed using HPLC-DAD, SDS-PAGE, FT-IR, circular dichroism, and spectrophotometric assays. Antioxidant activity was assessed by DPPH radical scavenging and reducing power assays, while antimicrobial activity was evaluated against oral pathogens using diffusion and MIC methods. In vitro biological activity was investigated using MTT viability and scratch migration assays on human OSCC cell lines (SCC-9 and HSC-3). Results: The biocomposites preserved the structural integrity of type I collagen and incorporated polysaccharides and polyphenols from G. lucidum. The combined formulations showed enhanced antioxidant and antimicrobial activities compared with collagen alone. In vitro assays demonstrated dose- and time-dependent reductions in OSCC cell viability and delayed cell migration, with effects comparable to those of G. lucidum extract. Conclusions: The G. lucidum–R. pulmo biocomposite exhibits favorable physicochemical properties and demonstrates antioxidant, antimicrobial, and in vitro antitumor activity. These findings support its potential as a multifunctional biomaterial for further investigation as an adjunct approach in oral cancer-related applications. Full article

Gastric cancer remains a leading cause of cancer-related mortality worldwide. Citrus fruits are rich in polyphenols, exerting antioxidant and chemo-preventive activities, and lemon peel represents a valuable source of such bioactive compounds. Previous studies showed that Citrus limon peel extracts (LPE) inhibited the activity of some enzymes of the antioxidant system and reduced the interleukin-6-dependent invasiveness of gastric and colon cancer cells. In the present study, we have investigated the effects of LPE on the human gastric adenocarcinoma AGS and MKN-28 cells and on the activity of a crucial redox enzyme, catalase (CAT). Indeed, LPE significantly reduced the cell viability and clonogenic potential of the gastric cancer cells and induced morphological changes indicative of cytotoxicity. Moreover, LPE modulated the intracellular redox homeostasis by decreasing levels of the hydrogen peroxide-related reactive oxygen species (ROS) while increasing those of superoxide anions and decreasing levels of superoxide dismutases (SODs). Western blotting analysis revealed that LPE downregulated CAT, SOD-1, SOD-2, and monoamine oxidase A (MAO-A) protein expression level in both cell lines. Finally, the extract inhibited CAT activity in a dose-dependent manner (IC₅₀ = 0.008 ± 0.003 mg/mL; K_i = 0.012 ± 0.002 mg/mL). These findings indicate that LPE exerts cytotoxic and redox-modulating effects through the inhibition of antioxidant enzymes and the alteration of ROS balance. Therefore, the agro-industrial by-product LPE could be considered as a promising natural source of polyphenolic compounds with potential applications in the prevention and therapy of gastric cancer. Full article