Search Results (2,027)

Background: Curcumin, a dietary polyphenol with anticancer potential, has been reported to enhance the efficacy of chemotherapeutic agents. Methods: The effects of combined curcumin and doxorubicin treatment on apoptosis and associated signaling pathways were investigated in human osteosarcoma HOS cells. Results: Combined treatment significantly reduced cell viability and induced apoptotic morphological changes, which were confirmed by increased sub-G1 population, enhanced DNA fragmentation, and elevated cleaved poly(ADP-ribose) polymerase (PARP) levels. Mechanistically, combined treatment markedly increased c-Jun N-terminal kinase (JNK) phosphorylation, whereas extracellular signal-regulated kinase (ERK) phosphorylation showed no appreciable change. Pharmacological inhibition revealed that JNK suppression attenuated PARP cleavage, while ERK inhibition also reduced apoptotic responses, suggesting a permissive role of basal ERK activity. In addition, combined treatment was associated with increased expression of the endoplasmic reticulum stress marker GRP78 and modulation of autophagy-associated markers. Although thioredoxin domain-containing protein 5 (TXNDC5) expression was reduced, TXNDC5 overexpression failed to attenuate apoptosis, indicating that apoptosis induction occurs independently of TXNDC5. Conclusions: These findings indicate that combined curcumin and doxorubicin induce apoptosis primarily through JNK-dependent MAPK signaling, accompanied by stress-associated cellular responses. Full article

Theaflavin-3,3′-digallate (TF3), a flavan-3-ol derivative found in black tea, exhibits anti-tumor activity, but its mechanism of action in hepatocellular carcinoma (HCC) remains to be elucidated. Here we systematically delineate how TF3 targets Pin1 to suppress HCC through an integrated approach combining computational simulations, enzyme assay and cell-based assays. TF3 spontaneously occupies the active site of Pin1 with a docking score of −8.9 kcal/mol, inhibiting its PPIase activity (IC₅₀ = 60.33 μmol/L) and yielding a binding constant (K_a) of 3.1 × 10⁵ mol/L. Drug affinity responsive target stability (DARTS) assays further corroborated that TF3 directly engages Pin1 within HCC cells. Functionally, TF3 potently suppressed the viability of HepG2, SK-Hep-1 and Huh-7 cells in both dose- and time-dependent manners (IC₅₀ = 61.22, 14.09 and 69.85 μmol/L at 24 h, respectively), and exhibited a modest selectivity window against the viability of L02 and THLE-2 cells (IC₅₀ = 133.43 and 90.29 μmol/L at 24 h, respectively). In addition, TF3 triggers mitochondrial-mediated apoptosis, evidenced by ROS accumulation, loss of mitochondrial membrane potential, an elevated Bax/Bcl-2 ratio, cytochrome c release and enhanced PARP cleavage, and induces G₂/M phase arrest. It also robustly inhibits HCC cell proliferation, invasion and migration, coinciding with downregulation of proteins governing cell cycle progression and invasive behavior. Transcriptome profiling coupled with enrichment analysis discovered that TF3 treatment differentially regulated 5009 genes, which were prominently enriched in pathways linked to apoptosis, cell cycle control, MAPK and PI3K/AKT signaling pathways. Western blotting analysis revealed that TF3 selectively suppresses phosphorylation of p38 and the PI3K/AKT cascade, activating JNK phosphorylation. In summary, our findings indicate that TF3 suppresses HCC proliferation by targeting Pin1, with attendant modulation of the MAPK and PI3K/AKT pathways, thereby presenting a potential candidate for targeted HCC therapy. Full article

Although the parental recombinant protein rLj-RGD3 exhibits antitumor activity, it carries immunogenicity risks owing to its large molecular size (13.5 kDa). We generated a genetically truncated mutant, rLj-RGD4 (6.27 kDa, four RGD motifs), which inhibited B16 melanoma cell proliferation, migration, and invasion in vitro. However, the in vivo efficacy and mechanisms of action remain unclear. Here, B16 xenograft mice were treated with rLj-RGD4 (5, 10, and 20 μg/kg i.p. daily for 14 days). Tumor growth was measured, and histopathology/apoptosis was evaluated using hematoxylin and eosin (HE), Masson’s dye, Hoechst, and TUNEL staining. Apoptotic pathways (mitochondrial, death receptor, and MAPK) were analyzed via Western blotting, whereas endocytosis mechanisms were explored using inhibitors (filipin III, NaN₃, cytochalasin D), and EGFR (epidermal growth factor receptor) interactions via fluorescence co-localization and phosphoprotein assays. The results demonstrated dose-dependent tumor growth inhibition (21.60–89.26% volume reduction, 41.03–86.51% weight reduction), with histological evidence of tissue loosening, fibrosis, and apoptosis. rLj-RGD4 induced apoptosis by activating the mitochondrial (Bax/Bcl-2 upregulation), death receptor (caspase-8 activation), and MAPK (JNK/p38 phosphorylation) pathways. Internalization was blocked by NaN₃ and cytochalasin D, indicating actin-dependent macropinocytosis. Direct EGFR binding was confirmed, accompanied by reduced EGFR expression and the inhibition of FAK/AKT/Src signaling. In conclusion, rLj-RGD4 exerts potent in vivo antitumor activity via two mechanisms: induction of multi-pathway apoptosis and EGFR-targeted suppression of pro-survival signaling. RGD4 exerts its antitumor function in vivo by targeting and co-internalizing with EGFR. Full article

Background: Astragalus membranaceus Fisch. ex Bunge has long been used in East Asian medicine for gastrointestinal disorders and immune modulation. Astragaloside IV (AS-IV), a major bioactive saponin from its roots, exhibits potent anti-inflammatory and antioxidant activities, yet its protective effects against inflammatory bowel disease (IBD)-associated multi-organ damage via the gut–liver–brain axis remain unclear. Methods: Experimental colitis was induced in C57BL/6N mice by administering 5% dextran sulfate sodium (DSS) in drinking water for seven days. AS-IV (100 mg/kg/day) was orally administered during DSS exposure. Disease severity was evaluated using body weight, colon length, disease activity index, and histopathology. Inflammatory cytokines and oxidative stress markers were measured using ELISA, and NF-κB and MAPK signaling were analyzed through Western blotting and immunohistochemistry in colonic, hepatic, and brain tissues. Results: AS-IV significantly alleviated DSS-induced weight loss, disease activity, and colon shortening, while improving intestinal histopathological damage. AS-IV also reduced systemic pro-inflammatory cytokine levels and oxidative stress. Mechanistically, AS-IV was associated with a reduced expression of phosphorylated NF-κB and MAPK proteins, including p-NF-κB, p-IκBα, p-ERK, p-JNK, and p-p38, across the colon, liver, and brain. Conclusions: AS-IV attenuates DSS-induced multi-organ inflammation via gut–liver–brain axis modulation through NF-κB and MAPK pathway inhibition in experimental colitis models. Full article

Cholinergic dysfunction and impaired synaptic plasticity are key mechanisms underlying cognitive decline in neurodegenerative conditions, including Alzheimer’s disease (AD). Schisandra chinensis pomace (SSP), a by-product of fruit processing, contains bioactive lignans and polyphenols with reported neuroprotective properties; however, its effects under cholinergic dysfunction have not been systematically investigated. In this study, the effects of SSP on scopolamine-induced cognitive impairment were evaluated using ex vivo electrophysiological and in vivo behavioral approaches. Multi-electrode array recordings demonstrated that SSP at 0.1 mg/mL significantly restored scopolamine-suppressed hippocampal long-term potentiation (LTP), whereas a higher concentration (1.0 mg/mL) did not restore hippocampal synaptic potentiation. In vivo, C57BL/6N mice received oral SSP (50 or 100 mg/kg/day) for six weeks, with scopolamine administered during the final three weeks. SSP at 50 mg/kg prevented scopolamine-induced body weight loss, attenuated hyperlocomotor activity, and significantly improved memory retention, as evidenced by enhanced performance in the passive avoidance and Morris water maze tests. Furthermore, SSP restored hippocampal brain-derived neurotrophic factor (BDNF) expression and reduced the p-JNK/JNK ratio, indicating modulation of neurotrophic and stress-responsive signaling pathways. Collectively, these findings suggest that SSP attenuates scopolamine-induced cholinergic dysfunction, accompanied by improved hippocampal synaptic plasticity and changes in BDNF and JNK signaling. These results support the potential of SSP as a neuroactive botanical resource under cholinergic challenge. Full article

Objectives: This study aimed to investigated the role of Giardia extracellular vesicles (EVs) in intercellular communication and to evaluated their potential as vaccine candidates. Methods: The immunomodulatory effects of Giardia EVs were assessed in mouse macrophages and human monocyte-derived dendritic cells (Mo-DCs), with a particular focus on key inflammatory signaling pathways. In vivo immunogenicity was evaluated following EV administration, and the antigenic composition of EV cargo was characterized by proteomic analysis. Results: Giardia EVs activated pro-inflammatory signaling pathways in mouse macrphages, including SAPK/JNK, ERK1/2, and NF-κB. This activation was associated with IκB-α degradation and nuclear translocation of p65. Furthermore, EV stimulation significantly upregulated the expression of pro-inflammatory genes, including Il1β, Il6, Il4, Ptgs2, Nos2, and Tnf, with log₂ fold changes ranging from 3.9 to 15.8. Consistently, EVs increased iNOS protein expression (28–45%) and nitrite production (9.6–12.3-fold). In human Mo-DCs, Giardia EVs promoted cellular maturation, as evidenced by increased expression of MHC-II, CD80, and CD86, and enhanced T-cell proliferation with a Th1-skewed profile. In vivo immunization induced antigen-specific antibody responses, with IgG subclass distribution indicative of a balanced Th1/Th2 response. Proteomic analysis identified immunoreactive EV-associated proteins, including elongation factor 1-alpha, α-7.3 giardin, tubulin, and variant surface proteins (VSPs), which are well-established antigens in Giardia infection, with prominent bands observed at approximately 22 kDa and 50 kDa. Conclusions: Collectively, these findings demonstrate that Giardia EVs modulate innate immune responses in vitro, elicit antigen-specific humoral immunity in vivo, and contain conserved immunogenic proteins. These properties support their potential as a promising cell-free vaccine platform against giardiasis. Full article

The mitogen-activated protein kinase (MAPK) pathways, ERK, JNK, and p38, are key regulators of immune responses during viral infections. These signaling cascades control cytokine production, T cell activity, and antigen presentation. However, many viruses can hijack MAPK pathways to avoid immune detection, promote their replication, and establish chronic infection. In this review, we discuss how different viruses, including HSV-1, HBV, HCMV, and SARS-CoV-2, manipulate MAPK signaling to alter host cell functions. A particular focus is given to the CD1d–iNKT cell axis, which plays a critical role in early antiviral responses but is often disrupted through MAPK-dependent mechanisms. We explore how changes in MAPK signaling affect antigen-presenting cells, drive T cell exhaustion, and reprogram immune cell metabolism, factors that contribute to viral immune evasion. The review also examines therapeutic strategies aimed at targeting MAPKs to improve antiviral immunity. These include small-molecule inhibitors and immune modulators that may enhance antiviral responses while limiting side effects. We emphasize the importance of context, as MAPK-targeted therapies must be carefully timed and tailored to avoid suppressing protective immunity or triggering unwanted inflammation. Overall, this review highlights the therapeutic potential and challenges of targeting MAPK pathways in viral infections and encourages further research into selective, host-directed antiviral strategies. Full article

Vascular endothelial growth factor (VEGF)-driven pathological angiogenesis constitutes a primary driver of neovascular diseases, including neovascular age-related macular degeneration (nAMD) and diabetic retinopathy (DR). Although anti-VEGF agents demonstrate clinical efficacy, their limited intraocular half-life mandates repeated intravitreal injections, thereby highlighting the imperative for long-term therapeutic strategies. In the present study, we assessed the anti-angiogenic potential of retinal organoid-derived microRNAs (miRNA) delivered via an engineered adeno-associated virus vector. Human umbilical vein endothelial cells (HUVEC) were transduced with AAV2.7m8 vectors to overexpress three candidate miRNA (miR-26a, miR-122, and let-7a), followed by VEGF stimulation to evaluate downstream signaling pathways and angiogenic responses. AAV2.7m8-mediated transduction of HUVEC demonstrated high efficiency without inducing detectable cytotoxicity. Overexpression of these miRNA markedly attenuated VEGF-induced phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 MAPK. Functional assays demonstrated suppression of endothelial cell proliferation and cell cycle progression, with miR-122-5p additionally inhibiting migration. All three miRNA substantially inhibited capillary-like tube formation. In aggregate, these results affirm that AAV2.7m8-mediated delivery of retinal organoid-derived miRNA —namely miR-26a-5p, miR-122-5p, and let-7a-5p—markedly suppresses VEGF-induced angiogenic signaling cascades and endothelial cell activation in vitro, thereby establishing their viability as a sustained therapeutic approach for pathological retinal neovascularization. Full article

Plant-derived saponins have attracted significant interest for their potential to promote apoptotic cell death and enhance antitumor immune responses through immunogenic cell death (ICD). Akebia quinata, a saponin-rich medicinal plant, exhibits diverse pharmacological properties; however, studies on its seeds are limited, and their immunomodulatory activity in cancer remains largely unexplored. In this study, A. quinata seeds were extracted using 70% ethanol, and the phytochemical profile was characterized using UHPLC–QTOF MS/MS. We investigated the anticancer properties of A. quinata seed extract (AQSE), focusing on its role in inducing apoptosis and ICD in non-small cell lung cancer (NSCLC). In human NSCLC cell lines (A549 and H460), AQSE exhibited potent cytotoxic effects in a dose-dependent manner. Flow cytometric analysis confirmed the induction of apoptosis, evidenced by a significant increase in Annexin V-positive cells and an elevated sub-G1 population. Mechanistically, AQSE treatment induced cell death by simultaneously inhibiting the survival-promoting MEK/ERK/CREB axis and activating the stress-responsive JNK pathway. Furthermore, AQSE triggered hallmark features of ICD, characterized by surface exposure of calreticulin and the release of extracellular HMGB1 and ATP. Most importantly, an in vivo vaccination assay using a syngeneic mouse model demonstrated that immunization with AQSE-treated dying cells significantly suppressed tumor growth upon rechallenge, confirming the establishment of antitumor immunological memory. Additionally, bioassay-guided fractionation revealed that the anticancer activity was primarily concentrated in the ethyl acetate fraction. These findings suggest that AQSE exerts anticancer effects via the induction of apoptosis and ICD, highlighting its potential as a promising natural candidate for the development of novel therapeutic strategies against NSCLC. Full article

Background: Cancer has emerged as the primary cause of death worldwide in recent years. Current cancer treatment strategies require improvement, creating a pressing need for the development of novel therapeutic agents. This study investigated the anticancer effects of a series of newly synthesized tri- and difluoromethylated spiro[5.5]trienone compounds and evaluated the antitumor efficacy of a lead compound, 3s. Methods: The methyl thiazolyl tetrazolium (MTT) assay was used to assess the effect of the trienone compounds on the growth of cancer cells. Cell cycle distribution and intracellular reactive oxygen species (ROS) levels were analyzed by flow cytometry. Protein expression was examined by Western blot. A mouse xenograft model was utilized to test the anticancer effects and toxicity of 3s in vivo. Results: All 21 tri- and difluoromethylated spiro[5.5]trienones exhibited inhibitory effects on the growth of cancer cells. Among them, compound 3s showed the strongest inhibitory effect. It induced cell cycle arrest at the G2/M phase and promoted apoptosis. Mechanistically, 3s activated JNK and ERK signaling and elevated intracellular ROS levels. Furthermore, in a mouse xenograft model, 3s significantly inhibited tumor growth with minimal toxicity. Conclusions: Compound 3s exhibits potent anticancer efficacy both in vitro and in vivo. The discovery of 3s offers new potential for cancer therapy. Full article

Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) possesses dual enzymatic functions, i.e., kinase and E3 ubiquitin ligase activities, orchestrating proliferation, survival, apoptosis, DNA damage response, and immune modulation. Recent genomic and mechanistic studies have revealed MAP3K1’s paradoxical, context-dependent roles as both an oncogene and a tumor suppressor. We discuss MAP3K1’s multidomain architecture, featuring an N-terminal RING and PHD domain (E3 ligase activity), a TOG domain (microtubule dynamics), and a C-terminal kinase domain, enabling the integration of c-jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38 MAPK), extracellular signal-regulated kinase (ERK), and nuclear factor kappa B (NF-κB) signaling pathways. MAP3K1 functions as a molecular switch balancing survival and apoptosis, with caspase-3 cleavage at Asp878 activating pro-apoptotic JNK/p38 signaling. Genomic analyses across >35 cancer types reveal MAP3K1 alterations at frequencies of <1–14%, highest in breast and endometrial cancers. These alterations show tissue specificity: loss-of-function mutations predominate in hormone receptor-positive breast cancer with a favorable prognosis, whereas gain-of-function mutations in melanoma activate oncogenic ERK signaling. MAP3K1 mutations predict response to mitogen-activated protein kinase kinase (MEK) and phosphoinositide 3-kinase (PI3K) inhibitors, with mutant cancers showing higher MEK inhibitor response than wild-type tumors. Despite substantial progress, critical gaps remain regarding MAP3K1’s E3 ligase substrates, context-dependent activity determinants, and therapeutic strategies. Addressing these through inhibitor development, biomarker validation, and mechanistic studies will accelerate potential clinical translation of MAP3K1 biology. Full article

Herbal melanin (HM), previously reported for its antiproliferative and pro-apoptotic properties, has garnered interest as a promising anti-colorectal cancer drug. However, HM’s biological effects and underlying molecular mechanisms and the related signaling pathways in colorectal cancer (CRC) cell motility are poorly investigated. To evaluate the impact of various concentrations (50, 100, and 200 μg/mL) of HM on cell migration, invasion, and tumorigenicity on human HT29 and SW620 CRC cell lines, a real-time cell analyzer instrument and colony formation assays were employed, respectively. An angiogenesis-related protein array was also used, and the levels of protein expression contributing to colony formation and extracellular proteolysis-driven cell migration and invasion, such as E-cadherin, N-cadherin and urokinase-type plasminogen activator receptor (uPAR), were monitored using Western blotting and RT-qPCR technologies. HM significantly decreased CRC cell motility, invasiveness, and formation of colonies, associated with E-cadherin upregulation and N-cadherin downregulation. In addition, HM specifically inhibited uPAR expression levels, which were also decreased by the pharmacological mitogen-activated protein kinase (MAPK) kinase (MEK) inhibitor UO126 and Jun N-terminal kinase (JNK) inhibitor SP600125, in both CRC cell lines, including metastatic CRC (mCRC) SW620 cell line. Addition of HM to cells pretreated with JNK and MEK inhibitors attenuated the blockade of JNK and ERK phosphorylation and alleviated HM-downregulated uPAR expression and HM-inhibited mCRC cell migration. In conclusion, our in vitro studies demonstrate that HM exhibits an inhibitory effect on CRC migration and invasiveness, associated with uPAR downregulation through JNK and ERK pathways. Full article

Cadmium (Cd) is an environmental toxicant originating from both natural processes and human activities. Cd has been strongly associated with multiple diseases, including breast cancer (BC). Background/Objective: Environmental Cd exposure represents a significant contributor to BC onset and progression. Cd-induced breast carcinogenesis is driven by a constellation of molecular events, including DNA damage, oxidative stress (OS), and the dysregulation of key signaling pathways. These include the ERK/JNK/p38 MAPK cascade, the PI3K/AKT/mTOR axis, NF κB activation, and Wnt signaling, all of which collectively promote tumor initiation, survival, and metastasis. This review underscores the complex interplay between Cd exposure and its effects on cancer-triggering factors. Methods: The complexity of the mechanisms Cd-induced BC, underlying Cd-induced BC makes it challenging to treat, highlighting the need for novel therapeutic strategies that complement or enhance conventional chemotherapy. Therefore, this review was developed by reviewing the literature and presenting the different aspects of the challenge associated with Cd exposure and BC therapy. Results: Phytochemicals, especially phenolics, alkaloids, carotenoids, terpenoids, and related plant-derived compounds, have emerged as promising candidates for mitigating Cd-induced BC. Their antioxidants, anti-estrogenic, and anti-inflammatory properties position them as potential chemopreventive and therapeutic agents capable of counteracting Cd’s molecular toxicity. Conclusions: The review presents current evidence linking Cd exposure to BC development and highlights the protective potential of selected phytochemicals in preventing or attenuating Cd-induced BC. Understanding these interactions reinforces the importance of phytochemical-based interventions as a strategy to reduce Cd-related cancer risk and support breast health. Full article

Myeloid differentiation factor 88 (MyD88) signaling plays a central role in inflammatory pathway activation. Adipose-derived interleukin-10 (IL-10), which is induced by insulin and lipopolysaccharides, suppresses hepatic glucose production. This study investigated the role of MyD88/IL-10 signaling in diabetes-induced systemic inflammation and hepatic gluconeogenesis. Stromal vascular fractions (SVFs) were isolated from the adipose tissue of Lepr^db/db and Lepr^db/dbMyD88^−/− mice and treated with IL-10 followed by analysis of inflammatory cytokine expression. IL-10 (10 or 50 ng) was injected into adipose tissue of type 2 DM (T2DM) (Lepr^db/db) mice to investigate its effect on blood dipeptidyl peptidase-4 (DPP4) activity, insulin resistance, and hepatic gluconeogenic signaling. Hepatic inflammatory markers, gluconeogenic gene expression, and metabolic parameters were assessed. Compared with wild-type mice, Lepr^db/db mice exhibited significantly reduced FOXP3 protein expression and IL-10 levels in adipose tissue, accompanied by increased blood DPP4 activity and adiponectin levels, elevated hepatic inflammatory cytokines, and increased G6pc and Pck1 mRNA expression. In contrast, Lepr^db/dbMyD88^−/− mice showed increased Foxp3 protein and PDGFα mRNA expression, decreased IL-6 and CCL2 mRNA expression in SVFs, increased IL-10 levels in adipose tissue, and lower blood adiponectin and ALT levels. MyD88 deletion also attenuated Kupffer cell accumulation, hepatic inflammatory cytokine expression, and gluconeogenic gene expression. In vitro, IL-10 treatment of SVFs from Lepr^db/db mice significantly reduced IL-6 and CCL2 expression and increased Foxp3 mRNA expression. In vivo, adipose IL-10 injection increased Foxp3 and IL-10 expression, expanded Treg cells in SVFs, and activated hepatic Akt signaling, while suppressing pJNK and pNF-κB signaling. These changes were accompanied by reduced blood DPP4 activity, ALT and adiponectin levels, decreased Kupffer cell-derived inflammatory cytokines, reduced hepatic G6pc and Pck1 expression, and improved glucose tolerance. MyD88 signaling induces adipose IL-6 and CCL2, liver inflammation and gluconeogenesis, and blood DPP4 activity by reducing IL-10 and Foxp3 of adipose tissue in T2DM. Enhancing adipose IL-10 induces Treg expansion, inhibits JNK and NF-κB signaling, and alleviates hepatic gluconeogenesis and insulin resistance. MyD88 inhibition or IL-10 elevation in adipose tissue may represent a novel strategy for metabolic syndrome. Full article

The Golgi complex undergoes dynamic remodeling during the cell cycle, as ribbon unlinking in G2 is required for proper mitotic progression. Failure to fragment the ribbon leads to G2 arrest, whereas forced mitotic entry with intact ribbons results in multipolar spindle formation. Phosphorylation of the Golgi matrix protein GRASP65 at serine 277 (S277) in rat (S274 in human) by JNK2 is essential for ribbon unlinking, but its upstream regulation has remained unclear. Here, we generated and validated a phospho-specific antibody recognizing human GRASP65 phosphorylated at S274, enabling accurate detection of this modification. Using this tool, we identify protein kinase D2 (PKD2) as a critical upstream regulator required for GRASP65 phosphorylation and Golgi unlinking. GRASP65-S274 phosphorylation increases during G2 and is markedly reduced upon PKD2 inhibition or depletion, resulting in decreased Golgi unlinking and delayed G2/M transition. Conversely, PKD2-activating stimuli, including phorbol esters and nocodazole, enhance GRASP65 phosphorylation in a PKD2-dependent manner. These findings define PKD2 as a key regulator of the JNK2–GRASP65 signaling axis controlling Golgi disassembly at the G2/M transition. Moreover, the phospho-specific GRASP65 antibody described here provides a valuable tool to dissect upstream signaling mechanisms and to identify the initial triggers driving Golgi unlinking at G2 entry. Full article