Search Results (158)

Background/Objectives: Intrinsic radioresistance in non-small-cell lung cancer (NSCLC) is partially driven by adaptive redox mechanisms that prevent oxidative cell death. Ferroptosis, an iron-dependent form of regulated cell death characterized by lipid peroxidation, has emerged as a potential therapeutic vulnerability in tumors with elevated antioxidant capacity. However, its mechanistic integration with radiotherapy remains incompletely understood. Methods: We compared the effects of three clinically approved VEGFR-targeting tyrosine kinase inhibitors (TKIs), cabozantinib, lenvatinib, and ripretinib, on NSCLC cell viability with and without radiation. Subsequent mechanistic studies focused on cabozantinib and included ferroptosis rescue assays (ferrostatin-1, deferoxamine), lipid ROS quantification, glutathione assays, clonogenic survival, co-immunoprecipitation of BECN1–SLC7A11 complexes, and BECN1 knockdown by siRNA and shRNA. Results: All three TKIs were evaluated for cytotoxicity, but only cabozantinib significantly reduced NSCLC cell viability in combination with radiation in a ferroptosis-dependent manner. Cabozantinib inhibited STAT3 phosphorylation and downregulated MCL1, resulting in the release of BECN1. This allowed BECN1 to bind and suppress SLC7A11, disrupting system Xc⁻ function, depleting glutathione, and promoting lipid ROS accumulation. Genetic silencing of BECN1 reversed these effects and restored redox balance and clonogenic capacity. Lenvatinib and ripretinib failed to elicit similar responses, indicating that the inhibition of non-VEGFR targets (e.g., MET, AXL) may be essential for ferroptosis induction by cabozantinib. Conclusions: Cabozantinib enhances the radiosensitization of NSCLC cells through ferroptosis induction mediated by the suppression of the STAT3/MCL1/BECN1/SLC7A11 axis. These findings uncover a novel mechanism linking kinase inhibition to redox imbalance and suggest that the pharmacologic modulation of ferroptosis using multi-target TKIs may represent a rational approach to overcome radioresistance in NSCLC. Full article

Bovine endometritis can be caused by Escherichia coli (E. coli), from which the lipopolysaccharide (LPS) triggers TLR4/NF-κB-mediated inflammation and reactive oxygen species (ROS) overproduction, resulting in impaired reproductive performance. While NADPH oxidase (NOX) is a critical source of ROS generation, its role in bovine endometrial epithelial cells (BEEC) and modulation by selenium remains unexplored. In this study, primary BEEC was challenged by LPS to assess NOX2/4 expression kinetics. Inhibitors of NOX and NF-κB were applied to observe the role of NOX-derived ROS in BEEC inflammation and in selenomethionine (SeMet)-modulated anti-inflammation. ROS levels were measured by flow cytometry. The changes in inflammatory cytokines, and the proteins related to NOX4 and NF-κB, were analyzed via qPCR and Western blot. As a result, the inhibition of NOX decreased LPS-induced proinflammatory cytokine expression, ROS accumulation, NOX4 level, and the phosphorylation of NF-κB P65 and IκBα. Conversely, the suppression of NF-κB downregulated the levels of ROS and NOX4. Cotreatment with SeMet and a NOX inhibitor further suppressed the inflammatory response, ROS level, and NF-κB pathway activation compared to individual treatment, but had no additive effect on the NOX4 protein level. In conclusion, the NOX4/ROS/NF-κB axis forms a proinflammatory feedback loop in LPS-stimulated BEEC. SeMet mitigates oxidative stress and inflammation partially through NOX4 inhibition. Full article

Background/Objectives: The detection of ovarian cancer remains challenging due to the lack of reliable serum biomarkers that reflect malignant transformation rather than mere tumor presence. We developed a novel biotest using an immortalized human fallopian tube epithelial cell line (TY), which exhibits anchorage-independent growth (AIG) in response to cancer-associated serum factors. Methods: Sera from ovarian and breast cancer patients, non-cancer controls, and ID8 ovarian cancer-bearing mice were tested for AIG-promoting activity in TY cells. Results: TY cells (passage 96) effectively distinguished cancer sera from controls (68.50 ± 2.12 vs. 17.50 ± 3.54 colonies, p < 0.01) and correlated with serum CA125 levels (r = 0.73, p = 0.03) in ovarian cancer patients. Receiver operating characteristic (ROC) analysis showed high diagnostic accuracy (AUC = 0.85, cutoff: 23.75 colonies). The AIG-promoting activity was mediated by HGF/c-MET and IGF/IGF-1R signaling, as inhibition of these pathways reduced phosphorylation and AIG. In an ID8 mouse ovarian cancer model, TY-AIG colonies strongly correlated with tumor burden (r = 0.95, p < 0.01). Conclusions: Our findings demonstrate that the TY cell-based AIG assay is a sensitive and specific biotest for detecting ovarian cancer and potentially other malignancies, leveraging the fundamental hallmark of malignant transformation. Full article

Epicardial mesothelial cells (EMCs), which form the epicardium, play a crucial role in cardiac homeostasis and repair. Upon damage, EMCs reactivate embryonic development programs, contributing to wound healing, progenitor cell amplification, and regulation of lymphangiogenesis, angiogenesis, and fibrosis. However, the mechanisms governing EMC activation and subsequent regulation remain poorly understood. We hypothesized that hepatocyte growth factor (HGF), a pleiotropic regulator of various cellular functions, could modulate EMC activity. To verify this hypothesis, we developed HGF-overexpressing mesenchymal stromal cell sheets (HGF-MSC CSs) and evaluated their effects on EMCs in vitro and in vivo. This study has revealed, for the first time, that EMCs express the c-Met (HGF receptor) on their surface and that both recombinant HGF and HGF-MSC CSs secretome cause c-Met phosphorylation, triggering downstream intracellular signaling. Our findings demonstrate that the HGF-MSC CSs secretome promotes cell survival under hypoxic conditions by modulating the level of autophagy. At the same time, HGF-MSC CSs stimulate EMC proliferation, promoting their amplification in the damage zone. These data demonstrate that HGF-MSC CSs can be considered a promising regulator of epicardial cell activity involved in heart repair after ischemic damage. Full article

Acyl-CoA dehydrogenase 9 deficiency is considered as a rare neuromuscular syndrome with an autosomal recessive transmission. The ACAD9 protein presents two essential functions, i.e., the limiting step enzyme of the fatty acid β-oxidation pathway and one of the complex’s compounds involved in the respiratory chain complex I assembly. Thus, loss-of-function mutations are known to convey mitochondrial cytopathologies. A patient with a mild and late-onset phenotype, suffering from exercise intolerance and hypertrophic cardiomyopathy, was diagnosed as a compound heterozygote of the ACAD9 gene. The first c.1240C> T p.Arg414Cys variant has been previously reported and is known to be responsible for ACAD9 deficiency. However, the second c.1636G> A p.Val546Met variant has never been described. The goal was to investigate the eventual pathogenicity of this new genetic variant. For this purpose, molecular cloning was generated to express the ACAD9 gene with the V546M variant in a cell line (ACAD9mut) and compared to cells expressing the wild-type ACAD9. Then, the mitochondrial respiration, ATP production, the mitochondrial network, and the oxidative phosphorylation’s composition were investigated to reveal the effects of the V546M variant. While avoiding to affect the amount of the respiratory chain’s complexes, the new ACAD9 variant was entirely responsible for reducing over 50% of the mitochondrial complex I activity. Full article

Background: Treatment of metastatic cancer remains a challenge, because cancer cells acquire resistance even to the most contemporary therapies. This study analyzed the role of the phosphoprotein Stathmin 1 (STMN1) in regulating cancer cell growth and metastatic potential. Methods: Public datasets with metastatic castration-resistant prostate cancer (mCRPC) and breast cancer (BC) were analyzed to determine the interrelationship between STMN1, hepatocyte growth factor (HGF) and MET proto-oncogene (MET) expression, overall survival, and response to chemotherapy. Site-directed mutagenesis, cell cycle analysis, proliferation, and migration and invasion assays determined the impact of STMN1 phosphorylation on proliferation and metastatic potential. Results: Increased STMN1 associates with HGF and MET gene expression in mCRPC, and taxane chemotherapy further increases HGF expression. STMN1 and HGF are highest, and overall survival is poorest in mCRPC in the liver compared to other sites, implying the metastatic site influences their expression levels and potentially the pattern of metastatic spread. Increased STMN1 and MET also predict taxane responsiveness in BC patients. Analysis of STMN1 serine (S)16, 25, 38, and 63 determined that total (t) STMN1 and STMN1 S16 phosphorylation (pSTMN1^S16) are co-regulated by HGF/MET during cell cycle progression, pSTMN1^S16 alone can promote cell proliferation, and pSTMN1^S16 shortens the cell cycle similar to HGF treatment, while STMN1^S16 dephosphorylation lengthens the cell cycle to arrest cell growth in G2/M, similar to HGF plus the MET inhibitor AMG337. Importantly, STMN1^S16 does not promote metastasis. Conclusions: Selectively inhibiting STMN1^S16 phosphorylation may provide an alternative strategy for inhibiting MET-mediated cell growth to eliminate metastatic cancer cells and inhibit further metastasis. Full article

Disorders of vesicular trafficking and genetic defects in autophagy play a critical role in the development of metabolic and neurometabolic diseases. These processes govern intracellular transport and lysosomal degradation, thereby maintaining cellular homeostasis. In this article, we present two siblings with a novel homozygous variant in VPS51 (Vacuolar protein sorting 51) gene (c.1511C>T; p.Thr504Met), exhibiting developmental delay, a thin corpus callosum, severe intellectual disability, epilepsy, microcephaly, hearing loss, and dysphagia. This study aimed to investigate the effects of the novel VPS51 gene variation at the RNA and protein level in fibroblasts derived from patients. A comparative proteomic analysis, which has not been previously elucidated, was performed to identify uncharacterized proteins associated with vesicular trafficking. Furthermore, the impact of disrupted pathways on mitochondria–lysosome contact sites was assessed, offering a thorough pathophysiological evaluation of GARP/EARP (Golgi Associated Retrograde Protein / Endosome Associated Retrograde Protein) complex dysfunction. An analysis of mRNA expression indicated decreased levels of the VPS51 gene, alongside modifications in the expression of autophagy-related genes (LC3B, p62, RAB7A, TBC1D15). Western blotting demonstrated a reduction in VPS51 and autophagy-related protein levels. Proteomic profiling revealed 585 differentially expressed proteins, indicating disruptions in vesicular trafficking, lysosomal function, and mitochondrial metabolism. Proteins involved in mitochondrial β-oxidation and oxidative phosphorylation exhibited downregulation, whereas pathways related to glycolysis and lipid synthesis showed upregulation. Live-cell confocal microscopy revealed a notable increase in mitochondria–lysosome contact sites in patient fibroblasts, suggesting that VPS51 protein dysfunction contributes to impaired organelle communication. The findings indicate that the novel VPS51 gene variation influences intracellular transport, autophagy, and metabolic pathways, offering new insights into its involvement in neurometabolic disorders. Full article

Activation of cGAS, a cytosolic receptor recognizing double-stranded DNA, in macrophages is important in sepsis (a life-threatening condition caused by infection). The responses against sepsis induced by subcutaneous implantation of the Pseudomonas-contaminated catheters in cGAS-deficient (cGAS^−/−) mice were lower than in wild-type (WT) mice as indicated by liver enzymes, white blood cell count, cytokines, and M1-polarized macrophages in the spleens. Likewise, a lethal dose of lipopolysaccharide (LPS) induced less severe sepsis severity as determined by mortality, organ injury, cell-free DNA, and serum cytokines. Patterns of the transcriptome of lipopolysaccharide (LPS)-stimulated bone marrow-derived macrophages were clearly different between cGAS^−/− and WT cells. Gene set enrichment analysis (GSEA; a computational statistical determination of the gene set) indicated more prominent enrichment of oxidative phosphorylation (OXPHOS; the mitochondrial function) and mTORC1 pathways in LPS-activated cGAS^−/− macrophages compared with WT. Meanwhile, LPS upregulated cGAS and increased cGAMP (a cGAS inducer) only in WT macrophages along with less severe inflammation in cGAS^−/− macrophages, as indicated by supernatant cytokines, pro-inflammatory molecules (nuclear factor kappa B; NF-κB), M1 polarization (IL-1β, CD80, and CD86), and macrophage extracellular traps (METs; web-like structures composed of DNA, histones, and other proteins) through the detection of citrullinated histone 3 (CitH3) in supernatant and immunofluorescent visualization. In conclusion, less prominent pro-inflammatory responses of cGAS^−/− macrophages than WT were demonstrated in mice (catheter-induced sepsis and LPS injection model) and in vitro (transcriptomic analysis, macrophage polarization, and METs). Full article

Sarcopenic obesity (SO), characterized by an excess of fat and a decrease in muscle strength or mass, is a global public health concern and is linked to metabolic conditions such as metabolic syndrome (MetS). Different mechanisms contribute to SO, such as inflammation, fatty acid infiltration, and insulin resistance (IR). Recently, myostatin (MYOST), an inhibitory factor for skeletal muscle tissue, was proposed as an aimed compound for the treatment of conditions of muscular metabolic imbalance mass and MetS. On the other hand, a therapy with natural compounds such as resveratrol (R) and quercetin (Q) is effective for the treatment of MetS, but its effect on the MYOST pathway has been poorly explored. The control group received water, and the MetS group received 30% commercial sugar in the drinking water for 6 months. Polyphenol mix (R at a dose of 50 mg/kg/day and Q at 0.95 mg/kg/day) was administered for 1 month. MetS rats present SO linked to an increase in the expression of MYOST/ActRIIA and ActRIIB (p < 0.0001). R+Q treatment prevented SO by lowering the expression of MYOST and its receptors and increased the expression of Smad 7 in MetS rats (p < 0.0001). Moreover, the polyphenol treatment reverted IR by increasing Akt phosphorylation, leading to an increase in muscle mass. It decreased lipid stores, restored glycogen accumulation, and increased myosin expression (p < 0.0001). The results of this work indicate that R+Q supplementation could be a promising therapeutic agent to prevent SO and sarcopenia derived from other metabolic alterations. Full article

Metabolic syndrome (MetS) poses considerable toxicological risks due to its association with an increased likelihood of metabolic dysfunction-associated steatotic liver disease (MASLD), and is characterized by hypertension, hyperglycemia, dyslipidemia, and obesity. This study aimed to investigate the therapeutic potential of flavonoid-rich lotus seedpod extract (LSE) in alleviating MetS and MASLD-related hepatic disturbances. In vivo, mice subjected to a high-fat diet (HFD) and streptozotocin (STZ) injection were supplemented with LSE or simvastatin for 6 weeks. Obesity indicators included body weight and epididymal fat, while insulin resistance was measured by fasting serum glucose, serum insulin, homeostasis model assessment–insulin resistance index (HOMA-IR), and oral glucose tolerance (OGTT). Also, the levels of serum lipid profiles and blood pressure were evaluated. Adipokines, proinflammatory cytokines, liver fat droplets, and peri-portal fibrosis were analyzed to clarify the mechanism of MetS. LSE significantly reduced the HFD/STZ-induced MetS markers better than simvastatin, as demonstrated by hypoglycemic, hypolipidemic, antioxidant, and anti-inflammatory effects. In vitro, LSE improved oleic acid (OA)-triggered phenotypes of MASLD in hepatocyte HepG2 cells by reducing lipid accumulation and enhancing cell viability. This effect might be mediated through proteins involved in lipogenesis that are downregulated by adenosine monophosphate-activated protein kinase (AMPK). In addition, LSE reduced reactive oxygen species (ROS) generation and glycogen levels, as demonstrated by enhancing insulin signaling involving reducing insulin receptor substrate-1 (IRS-1) Ser307 phosphorylation and increasing glycogen synthase kinase 3 beta (GSK3β) and protein kinase B (PKB) expression. These benefits were dependent on AMPK activation, as confirmed by the AMPK inhibitor compound C. These results indicate that LSE exhibits protective effects against MetS-caused toxicological disturbances in hepatic carbohydrate and lipid metabolism, potentially contributing to its efficacy in preventing MASLD or MetS. Full article

We aimed to evaluate the therapeutic potential of crizotinib, a broad-spectrum tyrosine kinase inhibitor against bladder cancer (BC) cells, based on a three-dimensional (3D) cell culture system. After proliferating cell masses (spheroids) using T24 cisplatin-naïve and T24R2 cisplatin-resistant human BC cell lines, the spheroids were exposed to various crizotinib concentrations in order to derive an ideal crizotinib concentration to suppress cell survival, migration, and invasion. Crizotinib suppressed cell proliferation, migration, and invasion in both T24 and T24R2 BC cell lines under a 3D spheroid model, which was more appropriate than the conventional two-dimensional cell culture model. Real-time quantitative polymerase chain reaction analysis revealed a reduced expression of E-cadherin and an enhanced expression of vimentin, suggesting EMT suppression and the subsequent suppression of tumor aggressiveness following crizotinib administration. Meanwhile, the expressions of apoptosis-related genes increased. Western blot analysis revealed that the expression levels of phosphorylated mesenchymal–epithelial transition factor (c-Met) and phosphorylated Akt decreased following crizotinib administration, suggesting that the antitumor effect of crizotinib can be associated with the inhibition of the phosphorylated activation of the c-Met/PI3K/Akt pathway. Crizotinib showed a potential antitumor effect on both cisplatin-naïve and cisplatin-resistant human BC cells, likely through c-Met-induced PI3K/Akt pathway inhibition. Full article

The development of small-molecule drugs targeting growth factors for cancer therapy remains a significant challenge, with only limited successful cases. We attempted to identify hepatocyte growth factor (HGF) inhibitors as novel anti-cancer small-molecule drugs. To identify compounds that bind to the β-chain of HGF and inhibit signaling through HGF and its receptor Met interaction, we performed a hierarchical in silico drug screen using a three-dimensional compound structure library (Chembridge, 154,118 compounds). We experimentally tested whether 10 compounds selected as candidates for novel anticancer agents exhibit inhibition of HGF activity. Compounds 6 and 7 potently inhibited Met phosphorylation in the human EHEMES-1 cell line, with IC₅₀ values of 20.4 and 11.9 μM, respectively. Molecular dynamics simulations of the Compound 6/7–HGF β-chain complex structures suggest that Compounds 6 and 7 stably bind to the interface pocket of the HGF β-chain. MM-PBSA, MM-GBSA, and FMO analyses identified crucial amino acid residues for inhibition against the HGF β-chain. By interfering with the HGF/Met interaction, these compounds may attenuate downstream signaling pathways involved in cancer cell proliferation and metastasis. Further optimization and comprehensive evaluations are necessary to advance these compounds toward clinical application in cancer therapy. Full article

Background: The function of hepatocyte growth factor activator inhibitor (HAI)-1 and HAI-2 in bladder cancer has not been well evaluated. In a previous study, we reported upregulated MET phosphorylation and decreased expression of HAI-1 in bladder cancer as poor prognostic factors. In this study, we analyzed the therapeutic effect of HAI-1 and HAI-2 on bladder cancer cells through the inhibition of MET phosphorylation. Methods: We established stable HAI-1 and HAI-2 overexpression KU-1 cell lines (HAI-1 OE and HAI-2 OE) and HAIs knockdown T24 cell lines (HAI-1 KD and HAI-2 KD). These cell lines were used for cell proliferation, migration, and invasion assay. Next, the cell lines were injected with human fibroblasts subcutaneously in mice, and inhibition of growth was evaluated. Result: Significant inhibition in cancer cell proliferation, motility, and invasiveness was observed in HAI-1 OE and HAI-2 OE compared with the mock in the presence of HGF zymogen, whereas significant upregulation in cancer cell proliferation, motility, and invasiveness was observed in HAI-1 KD and HAI-2 KD cells. In vivo analysis showed significant inhibition of cancer cell growth in HAI-1 OE. Although a tendency toward the inhibition of growth was observed in HAI-2 OE, statistical significance was not achieved. Phosphorylation of MET in cancer tissues was downregulated in both cell lines. Conclusions: HAI-1 may have the therapeutic potential to reduce the growth of bladder cancer through the inhibition of MET phosphorylation. Full article

Background: Increased expression of MET and hepatocyte growth factor (HGF)-related molecules has been positively correlated with poor prognosis in renal cell carcinoma (RCC). In the current study, the expression and phosphorylation of MET in metastatic RCC (mRCC) are determined by immunohistochemistry, and the therapeutic effect of MET and HGF activation-targeting agents for RCC cell lines is analyzed. Methods: Immunohistochemistry was performed for 76 formalin-fixed paraffin-embedded specimens (primary tumor: 32, metastatic site: 44). The therapeutic effect of capmatinib (MET-I) and SRI-31215 (inhibitor of HGF-activating proteases: HGFA-I) was determined based on the inhibition of MET phosphorylation, cell proliferation, and cell migration in 786-O and caki-1 cell lines. Results: Increased expression and phosphorylation of MET were observed in both primary tumor and metastatic sites; however, phosphorylation was significantly upregulated in metastatic sites (p = 0.0001). In an assay of RCC cell lines, the strongest inhibition of MET phosphorylation, cell proliferation, and migration was confirmed with the combined used of MET-I and HGFA-I. Conclusions: Phosphorylation of MET was significantly upregulated in metastasis, which suggested the importance of downregulation in the treatment of mRCC. Our findings suggest that dual inhibition of MET and HGF activation may offer a promising strategy for mRCC treatment, warranting further clinical validation. Full article

Extensive studies have shown that gut microbiota-derived metabolites can enhance the antitumor efficacy of immunotherapy by modulating host immune responses. However, the more comprehensive spectrum of such metabolites and their mechanisms remain unclear. In this study, we demonstrated that L-selenomethionine (L-SeMet), a gut microbial metabolite, acts as a positive regulator of immunotherapy. Through screening of a repository of gut microbial metabolites, we identified that L-SeMet can effectively enhance the effector function of CD8⁺ T cells. Furthermore, intragastric administration of L-SeMet in mice significantly suppressed the growth of subcutaneous MC38 tumors. Mechanistically, L-SeMet enhances T cell receptor (TCR) signaling by promoting LCK phosphorylation. Collectively, our findings reveal that the gut microbial metabolite L-SeMet inhibits colorectal tumor growth by potentiating CD8⁺ T cell functions, providing a potential therapeutic strategy for colorectal cancer treatment. Full article