Background/Objectives: Endometrial cancer frequently develops resistance to thera-py, partly due to the ability of tumor cells to adapt to cellular stress through non-apoptotic mechanisms. Mitochondrial dysfunction and cytoskeletal remodeling are increasingly recognized as key components of stress adaptation; however, their structural relationship under pharmacological stress in three-dimensional (3D) tumor models remains poorly characterized. The present study aimed to investigate the ul-trastructural and phenotypic effects of lithium chloride (LiCl)–induced stress in 3D endometrial cancer spheroids, with a particular focus on mitochondrial alterations and intermediate filament organization. Methods: Three-dimensional spheroids gen-erated from Ishikawa endometrial cancer cells were exposed to lithium chloride at concentrations of 1, 10, or 50 mM for defined time periods. Cell viability, proliferative activity, and clonogenic capacity were assessed using Trypan Blue exclusion, BrdU in-corporation, and soft agar assays. Ultrastructural changes were examined by trans-mission electron microscopy to evaluate mitochondrial morphology, cytoplasmic or-ganization, and intermediate filament distribution. Results: LiCl exposure resulted in a dose- and time-dependent reduction in cell viability, proliferation, and clonogenic potential in 3D spheroids. Ultrastructural analysis revealed pronounced mitochondrial swelling, cristae disorganization, and membrane-associated mitochondrial alterations. These changes were consistently accompanied by conspicuous accumulation and re-organization of intermediate filaments in close spatial proximity to damaged mito-chondria. Across all experimental conditions, classical apoptotic ultrastructural fea-tures, including chromatin condensation and apoptotic body formation, were not ob-served, despite substantial organelle-level alterations. Conclusions: Together, these observations indicate that lithium chloride elicits a stress phenotype in 3D endometrial cancer spheroids that primarily manifests at the organelle and cytoskeletal levels, ra-ther than through classical apoptotic execution. Although descriptive in nature, the present study highlights intermediate filament accumulation as a prominent structural feature of lithium-induced mitochondrial stress and establishes a structural reference point for future studies aimed at dissecting mitochondrial–cytoskeletal interplay dur-ing pharmacological stress in endometrial cancer.

Background/Objectives: Endometrial cancer frequently develops resistance to therapy, partly due to the ability of tumor cells to adapt to cellular stress through non-apoptotic mechanisms. Mitochondrial dysfunction and cytoskeletal remodeling are increasingly recognized as key components of stress adaptation; however, their structural relationship under pharmacological stress in three-dimensional (3D) tumor models remains poorly characterized. The present study aimed to investigate the ultrastructural and phenotypic effects of lithium chloride (LiCl)-induced stress in 3D endometrial cancer spheroids, with a particular focus on mitochondrial alterations and intermediate filament organization. Methods: Three-dimensional spheroids generated from Ishikawa endometrial cancer cells were exposed to lithium chloride at concentrations of 1, 10, or 50 mM for defined time periods. Cell viability, proliferative activity, and clonogenic capacity were assessed using Trypan Blue exclusion, BrdU incorporation, and soft agar assays. Ultrastructural changes were examined by transmission electron microscopy to evaluate mitochondrial morphology, cytoplasmic organization, and intermediate filament distribution. Results: LiCl exposure resulted in a dose- and time-dependent reduction in cell viability, proliferation, and clonogenic potential in 3D spheroids. Ultrastructural analysis revealed pronounced mitochondrial swelling, cristae disorganization, and membrane-associated mitochondrial alterations. These changes were consistently accompanied by conspicuous accumulation and reorganization of intermediate filaments in close spatial proximity to damaged mitochondria, suggesting a structural association between cytoskeletal remodeling and mitochondrial injury. Across all experimental conditions, classical apoptotic ultrastructural features, including chromatin condensation and apoptotic body formation, were not observed. Conclusions: Together, these observations indicate that lithium chloride elicits a stress phenotype in 3D endometrial cancer spheroids that primarily manifests at the organelle and cytoskeletal levels, rather than through classical apoptotic execution. Although descriptive in nature, the present study highlights intermediate filament accumulation as a prominent structural feature of lithium-induced mitochondrial stress and establishes a structural reference point for future studies aimed at further investigating mitochondrial–cytoskeletal relationships during pharmacological stress in endometrial cancer.

Background: Ovarian cancer (OC) is characterized by aggressive progression, high metastatic potential, and frequent resistance to conventional chemotherapy, highlighting the need for novel combination-based therapeutic strategies. Metformin has emerged as a promising antineoplastic agent; however, its efficacy may be enhanced through combination with bioactive compounds. This study aimed to investigate the antineoplastic effects of metformin in SKOV3 human OC cells and to evaluate whether these effects could be potentiated by boric acid (BA) and resveratrol, with particular emphasis on their modulatory impact on key inflammatory and tumor-associated biomarkers, including interleukin-17 (IL-17), nuclear factor kappa-B (NF-κB), and midkine (MDK). Methods: SKOV3 cells were treated with metformin, BA, and resveratrol as monotherapies or in combination. Cell viability was assessed using a colorimetric assay, while migratory capacity was evaluated by wound healing analysis. The expression levels of IL-17, NF-κB, and MDK were quantified in cell lysates, and p21 protein expression was analyzed by immunocytochemistry. Results: All treatments induced concentration- and time-dependent reductions in cell viability. Combination treatments, particularly metformin with boric acid or resveratrol, produced more pronounced inhibitory effects on cell survival and migration compared with single-agent treatments. Inflammatory and tumor-associated biomarkers, including IL-17, NF-κB, and MDK, were significantly modulated following treatment. Additionally, increased p21 expression was observed in treated cells, indicating enhanced cell cycle regulatory activity. Conclusions: These findings indicate that BA and resveratrol enhance the antineoplastic activity of metformin in SKOV3 OC cells by suppressing proliferative and migratory capacities and modulating inflammatory mediators such as IL-17, NF-κB, and MDK. However, since toxicity assessments in non-cancerous cells were not performed, the safety profile of this combination remains unclear and requires further investigation in non-cancerous models.

Mitochondrial stress has emerged as a key regulator of tumor–immune interactions, extending beyond its classical bioenergetic role to coordinate metabolic adaptation and immune regulation. Rather than merely accompanying tumor progression, mitochondrial dysfunction contributes to immune evasion and resistance to immunotherapy. Here, we propose that mitochondrial stress functions as a unifying axis governing three key determinants of anti-tumor immunity: immune visibility, immune cell fitness, and the metabolic architecture of the tumor microenvironment. Mechanistically, mitochondrial reactive oxygen species, mitochondrial DNA release, and mitophagy modulate antigen presentation and T cell function. We further highlight emerging experimental platforms, including 3D spheroid and organoid systems, that enable physiologically relevant investigation of mitochondria-driven tumor–immune interactions. Together, this perspective provides a mechanistic framework for understanding and targeting resistance to immune checkpoint blockade.

Selective remodeling of nuclear architecture under pharmacological stress remains incompletely characterized in three-dimensional cancer models, particularly at the ultrastructural level. Lithium chloride (LiCl) is widely used as a cellular stressor capable of altering membrane organization, proliferation, and organelle dynamics; however, its effects on nucleus-associated structural remodeling in three-dimensional tumor systems remain unclear. In the present study, Ishikawa endometrial carcinoma spheroids were exposed to LiCl (10 or 50 mM) for up to 96 h, and cellular responses were evaluated using cell cycle analysis, 5-bromo-2′-deoxyuridine (BrdU) incorporation, viability assays, and transmission electron microscopy. LiCl exposure was associated with sustained accumulation of cells in the G₀/G₁ phase and suppression of DNA synthesis without evidence of a dominant apoptotic or necrotic response under the examined conditions. Ultrastructural analyses showed prominent nuclear envelope elongation, membrane reorganization, and perinuclear double-membraned structures, particularly under prolonged LiCl exposure. These alterations were observed alongside mitochondrial and endomembrane remodeling, supporting the presence of a broader stress-associated ultrastructural adaptation response within LiCl-treated spheroids. Importantly, the present study is morphology-focused and descriptive in scope. Although some ultrastructural features were morphology-compatible with nucleophagy-associated remodeling, no molecular validation using LC3, p62/SQSTM1, LAMP1/lysosomal colocalization, lamin degradation, or autophagic-flux assays was performed. Therefore, the findings should be interpreted as evidence of stress-associated nuclear envelope remodeling rather than mechanistic proof of nucleophagy. Collectively, this study identifies nucleus-associated ultrastructural remodeling as a prominent cellular response to LiCl-induced stress in 3D endometrial cancer spheroids and highlights the utility of three-dimensional tumor models for investigating stress-related architectural adaptations in cancer cells.

Ovarian cancer remains a major cause of gynecological cancer-related mortality, highlighting the need for novel therapeutic strategies capable of enhancing antitumor activity while targeting multiple mechanisms involved in tumor progression. Everolimus, an inhibitor of the mammalian target of rapamycin pathway, and carboplatin are established antineoplastic agents with distinct mechanisms of action, whereas astaxanthin is a bioactive carotenoid with antioxidant, anti-inflammatory, and potential anticancer properties. This study compared the individual and pairwise combination effects of carboplatin, everolimus, and astaxanthin on cell viability, migratory capacity, and inflammatory and tumor-associated biomarkers in SKOV3 ovarian cancer cells. Human SKOV3 ovarian cancer cells were cultured under standard conditions and exposed to different concentrations of carboplatin, everolimus, and astaxanthin, either individually or as pairwise two-drug combinations, for 24–72 h. Cell viability was assessed using the Cell Counting Kit-8 (CCK-8) assay. Cell migration was evaluated using a scratch wound-healing assay. Based on the experimental treatment protocol, 100 nM everolimus, 100 μM carboplatin, and 100 μM astaxanthin, alone and in combination, were further evaluated for their effects on β-defensin 1, β-defensin 2, α-defensin 1, tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β) levels. Biomarker concentrations were determined by ELISA. Experiments were independently performed in triplicate. Everolimus, carboplatin, and astaxanthin produced concentration- and time-dependent alterations in SKOV3 cell viability, with more pronounced cytotoxic effects generally observed following prolonged exposure. The pairwise combination treatments also substantially affected cell viability, particularly at later experimental time points. Assessment of migratory capacity demonstrated significant differences in wound closure among treatment groups at 24, 48, and 72 h (p = 0.0224, p = 0.0155, and p = 0.0028, respectively), indicating a time-dependent inhibitory effect on SKOV3 cell migration. Treatment with carboplatin, everolimus, and astaxanthin, individually or in pairwise combinations, also significantly modulated β-defensin 1, β-defensin 2, α-defensin 1, TNF-α, and IL-1β levels compared with control cells, with the magnitude and direction of these changes varying according to treatment regimen and exposure duration. Everolimus, carboplatin, and astaxanthin exerted significant time- and treatment-dependent effects on the viability and migratory behavior of SKOV3 ovarian cancer cells and markedly modulated defensin and pro-inflammatory cytokine responses. The findings demonstrate distinct treatment- and time-dependent responses to the individual agents and their pairwise combinations in SKOV3 ovarian cancer cells. These observations represent preliminary comparative in vitro effects rather than evidence of pharmacological synergy or therapeutic benefit. Further mechanistic studies using additional ovarian cancer cell lines, formal drug interaction analyses, and in vivo models are required to establish the biological and potential therapeutic relevance of these treatment combinations.