To define the functional role of Hakai within the m6A writer complex in colorectal cancer (CRC) and to determine how its modulation influences RNA methylation dynamics and tumour-immune interactions. Hakai was knockdown in CRC cell models, followed by RNA sequencing to assess transcriptomic changes and MeRIP-seq to evaluate m6A methylation patterns. Protein expression and immune-related markers were validated using Western blot, flow cytometry, ELISA, and RT-qPCR. Protein-protein interactions were analysed by co-immunoprecipitation, and subcellular localisation was assessed by cell fractionation. Functional immune assays were performed by exposing peripheral blood mononuclear cells from healthy donors and lamina propria mononuclear cells from CRC patients to conditioned media from Hakai-knockdown cells. Hakai knockdown induced phenotypic alterations in both 2D and 3D CRC models, despite minimal global transcriptomic changes. Notably, significant modifications in m6A methylation were observed, particularly in immune-related transcripts, including cytokines TNF, IFNB1, CXCL1, and CXCL8, accompanied by an overall reduction in m6A levels. Mechanistically, Hakai interacted with the writer-associated protein VIRMA and regulated METTL3 subcellular localisation. Functionally, conditioned media from Hakai-knockdown cells altered immune marker expression in patient-derived immune cells, indicating modulation of tumour-immune crosstalk. Hakai functions as a regulatory component of the m⁶A writer complex in CRC, influencing RNA methylation and immune-related gene expression. Our findings support a previously unrecognised role for Hakai in tumour-immune crosstalk and suggest its potential relevance in the modulation of the CRC tumour microenvironment.
Temozolomide resistance is a major barrier to effective glioma treatment and is frequently associated with enhanced DNA damage repair capacity. Although DPP9 has been linked to tumor development in several malignancies, whether it contributes to glioma therapeutic resistance has not been explored. Transcriptomic datasets, glioma specimens, and genetic gain- and loss-of-function approaches were employed to characterize DPP9 expression and function. RNA sequencing, co-immunoprecipitation, subcellular fractionation, and ubiquitination analyses were conducted to define the molecular basis of DPP9-mediated effects. Higher DPP9 expression was observed in glioma specimens and coincided with shorter patient survival. DPP9 depletion inhibited glioma growth and enhanced TMZ sensitivity in both cultured cells and xenograft tumors. Functional experiments support a role for altered RFWD3 localization in the association between DPP9 depletion and reduced RPA1 stability. Loss of DPP9 promoted RFWD3 redistribution to the cytoplasm, resulting in increased RPA1 ubiquitination and degradation. The reduction in RPA1 was accompanied by elevated replication stress, increased accumulation of DNA damage markers, and enhanced sensitivity to TMZ-induced genotoxic stress. Restoration of RPA1 expression attenuated these defects, indicating that RPA1 mediates a substantial portion of the cellular consequences associated with DPP9 loss. DPP9 contributes to glioma resistance to TMZ by sustaining RPA1-dependent DNA damage responses through regulation of the RFWD3-RPA1 axis. These results identify DPP9 as an important determinant of genome maintenance in glioma cells and nominate DPP9 as a candidate target for further investigation in TMZ-resistant glioma.
Uridine phosphorylase 1 (UPP1) is a key enzyme in the pyrimidine salvage pathway that catalyzes the reversible conversion of uridine into uracil and ribose-1-phosphate. While historically viewed as a housekeeping enzyme involved in nucleotide homeostasis, UPP1 has recently emerged as a context-dependent regulator that integrates cellular metabolism, oncogenic signaling, and immune modulation. Accumulating evidence suggests that UPP1 is frequently upregulated across a broad spectrum of cancers, functioning as a metabolic node that enables tumor cells to sustain growth under nutrient stress by diverting uridine-derived ribose into central carbon metabolism. Beyond its metabolic role, UPP1 also functions as a signaling co-regulator, engaging pathways such as the PI3K/AKT, NF-κB, and mTOR pathways to promote tumor proliferation, immune evasion, and therapeutic resistance. Notably, UPP1 exerts profound effects on the tumor immune microenvironment by shaping cytokine production, immune checkpoint expression, and the functional states of diverse immune and stromal cell populations, thereby facilitating immune suppression and metastatic progression. In parallel, emerging studies reveal that UPP1 plays important roles in non-neoplastic inflammatory conditions, including psoriasis, sepsis, and acute lung injury, highlighting its functional duality across malignant and inflammatory contexts. UPP1 expression is tightly controlled by multilayered regulatory mechanisms involving transcription factors, epigenetic modifications, non-coding RNAs, and extracellular cues, enabling its dynamic adaptation to metabolic and inflammatory stress. In this review, we synthesize recent advances to propose a unified conceptual framework in which UPP1 functions as an immunometabolic regulator rather than a simple metabolic enzyme. We discuss how its context-dependent activities contribute to tumorigenesis, immune remodeling, and inflammatory pathology, and highlight how targeting the UPP1-centered immunometabolic network may offer a promising intervention strategy to overcome resistance to cancer immunotherapy and modulate severe inflammatory responses.
Glutarylation, a newly identified form of protein acylation, has been linked to the regulation of tumor metabolism. However, the role of glutarylation in breast cancer is currently unclear. Multi-omics datasets analysis was employed to delineate the characteristics of XRCC4 in breast cancer. The roles of XRCC4 in breast cancer were validated using CCK-8, EdU, and colony formation assays. The glutarylation of XRCC4 was confirmed through bioinformatics predictions, immunofluorescence, and Co-IP experiments. In this study, we observed that the upregulation of XRCC4 was associated with a poor prognosis in patients with breast cancer. In vitro experiments showed that XRCC4 overexpression promoted the proliferation of breast cancer cells, whereas XRCC4 knockdown inhibited cell proliferation. Mechanistic analysis revealed that the XRCC4 protein can be glutarylated. Specifically, our findings showed that the deglutarylase SIRT5 binds to XRCC4 in the cytoplasm, promoting its expression at the protein level. Knockdown of XRCC4 promotes autophagy by inhibiting the p-mTOR/p-ULK1 pathway. XRCC4 glutarylation enhances the sensitivity of breast cancer to PARP inhibitors through the inhibition of mTOR activity and the promotion of autophagy, thereby offering additional options for maintenance therapy utilizing PARP inhibitors in breast cancer treatment.
The DNA damage response preserves genome integrity by detecting DNA lesions, activating checkpoint signalling, and coordinating repair with cell-cycle control. Defective or incomplete repair can promote mutation accumulation, chromosomal instability, cancer development, and ageing-associated diseases. In this review, we discuss the human single-stranded DNA-binding proteins hSSB1 and hSSB2, with an emphasis on their roles in ssDNA-rich repair intermediates generated during double-strand break repair, replication stress, oxidative base damage, telomere maintenance, and selected ultraviolet-damage responses. Both proteins contain oligonucleotide/oligosaccharide-binding fold domains that support ssDNA recognition and provide platforms for protein–protein interactions within DNA repair and chromatin-associated pathways. Current evidence identifies hSSB1 as a major regulator of ataxia telangiectasia mutated (ATM)/MRE11–RAD50–NBS1 (MRN)-dependent double-strand break signalling, RAD51-associated homologous recombination, human 8-oxoguanine DNA glycosylase 1 (hOGG1)-mediated repair of 8-oxo-guanine, replication-fork stability, and telomere protection. By contrast, hSSB2 remains less extensively characterised and appears to act in more restricted or context-dependent settings, including the cellular response to ultraviolet-induced DNA damage. We also discuss how post-translational modifications, SOSS/Integrator-associated complexes, transcriptional regulation, and possible epigenetic mechanisms shape hSSB1 and hSSB2 function. Finally, we highlight unresolved questions concerning the extent of functional overlap between these paralogues, the lack of damage-context-specific genome-wide binding maps, and the need to validate whether altered hSSB1 or hSSB2 expression can be exploited as a biomarker or therapeutic vulnerability in cancer.
Aberrant glycosylation contributes to cancer progression, but its histopathological and immune significance in endometrial cancer (EC) remains unclear. This study aimed to identify glycosylation-associated pathomic features as prognostic biomarkers and to explore how these alterations are associated with immune dysfunction and with computational indicators of immune escape and possible immunotherapy resistance in EC. We integrated pathomics with bulk and single-cell transcriptomics. Machine learning linked image features to N-glycan biosynthesis. Immune states, cell-cell communication, differentiation trajectories, and virtual MGAT4A knockout were analyzed computationally. Therapeutic response was predicted using TIDE and oncoPredict; no measured clinical outcomes were available. The optimal model stratified survival in the training and internal validation cohorts. The resulting glycosylation-associated pathomics RiskScore independently predicted prognosis and correlated with aggressive clinicopathological features. High-risk tumors exhibited upregulated cell cycle pathways, an immune-cold microenvironment, and computational indicators of checkpoint blockade resistance. MGAT4A was associated with poor prognosis and enriched in terminally differentiated CD8+ tissue-resident memory T cells (Trm). MGAT4A expression marked a putative “lock-and-load” dysfunction state: an inferred transcriptional pattern in which Trm cells remain armed with cytotoxic effector molecules (“loaded”) yet simultaneously display retention- and restraint-associated programs (“locked”), leaving them spatially trapped and functionally restrained. Virtual knockout generated regulatory hypotheses. A “Trapped Dysfunction Ratio” was associated with poor survival. This study identifies a glycosylation-associated CD8+ Trm dysfunction signature in EC. Glycosylation-associated pathomics features are associated with poor prognosis and with computational indicators of immune escape and possible immunotherapy resistance. MGAT4A represents a candidate biomarker requiring experimental and external validation.
Tumor metabolic reprogramming shapes the tumor microenvironment (TME) and modulates anti-tumor immunity, yet the interplay between metabolic adaptation and immune regulation in intrahepatic cholangiocarcinoma (ICC) remains unclear. We investigated the role of the glucose transporter GLUT1 (SLC2A1) as a potential immunometabolic regulator in ICC. We integrated bulk and single-cell transcriptomics with multi-omics profiling, and performed in vitro and in vivo functional validation. Pharmacologic inhibition was achieved using the selective GLUT1 inhibitor BAY-876. Single-cell analyses and tumor cell–macrophage co-culture assays were used to characterize immune composition and macrophage polarization. Mechanistic studies probed signaling pathways linking glucose transport to cytokine release and macrophage activation. GLUT1 expression was increased in malignant cholangiocytes and associated with worse prognosis. Single-cell data revealed stage-dependent GLUT1 dynamics, peaking at intermediate tumor states and declining during late-stage metabolic shifts toward lipid and MYC-driven programs. BAY-876 suppressed tumor cell proliferation and reduced tumor burden in preclinical models. High GLUT1 abundance correlated with an immune-suppressed TME reduced overall immune infiltration and predominance of M2-like macrophages, whereas GLUT1 inhibition increased tumor cell release of TNFα, activated NF-κB signaling in macrophages, and promoted M1-like polarization. Mechanistically, GLUT1 blockade activated p53 signaling and enhanced ADAM17 maturation, facilitating proteolytic release of TNFα and thereby engaging a p53/ADAM17/TNFα/NF-κB axis that links glucose transport to macrophage phenotype. These data nominate GLUT1 as an immunometabolic regulator in ICC and provide a rationale to evaluate GLUT1-directed strategies, alone or combined with immune-modulatory agents, to overcome metabolic heterogeneity and remodel the TME.
Osteosarcoma represents the most frequent primary malignant bone neoplasm in adolescents, with chemoresistance remaining a pivotal barrier to clinical cure and prognosis. Long non-coding RNAs (lncRNAs) are crucial epigenetic modulators governing malignant tumor progression, whereas lactylation constitutes a newly identified metabolic-epigenetic modification driving cancer chemoresistance. Nevertheless, the clinical significance and biological functions of chemoresistance- and lactylation-related lncRNAs (CRLR-lncRNAs) in osteosarcoma chemoresistance remain elusive. Osteosarcoma transcriptomic, clinical data, and scRNA-seq profiles were obtained from the TARGET database and the GSE152048 cohort, respectively. CRLR-lncRNAs were screened via Pearson correlation between lncRNAs and chemoresistance- and lactylation-related DEGs. A CRLR-lncRNA prognostic signature was constructed using LASSO and multivariate Cox regression, and validated by stratified survival analysis and nomogram. Functional enrichment, immune infiltration, drug sensitivity, tumor mutational burden (TMB), and Single-cell RNA-sequencing (scRNA-seq) analyses were further conducted. In vitro and in vivo assays were conducted to clarify the role and mechanism of the core lncRNA LINC01976 in osteosarcoma chemoresistance. Using the TARGET dataset, a novel prognostic signature consisting of 6 CRLR-lncRNAs was constructed and validated, exhibiting high accuracy in predicting 1-, 3-, and 5-year overall survival of osteosarcoma patients. It served as an independent prognostic factor superior to conventional clinicopathological indicators, with robust prognostic value across clinical subgroups and the capacity for individualized survival prediction. Functional enrichment analysis revealed enrichment in extracellular matrix remodeling, oncogenic signaling pathways, and immune-related processes. The signature effectively stratified patients into immune-active low-risk and immunosuppressive high-risk subgroups with distinct tumor immune microenvironments, TMB levels, and drug sensitivity. ScRNA-seq analysis confirmed the heterogeneous distribution and differential expression of signature lncRNAs between chemo-sensitive and chemo-resistant lesions. Notably, lactylation-related LINC01976 was upregulated in chemoresistant osteosarcoma and correlated with poor prognosis. Mechanistically, LINC01976 promotes cisplatin resistance in osteosarcoma both in vitro and in vivo by enhancing LDHA-dependent lactylation; specifically, LINC01976 upregulates LDHA expression, increasing intracellular lactate production and lysine lactylation levels alongside histone H3K18la, thus forming a LINC01976/LDHA/lactylation regulatory axis to further reinforce cisplatin resistance. The novel CRLR-lncRNA signature effectively predicts the prognosis, immune landscape, and chemosensitivity of osteosarcoma patients. LINC01976, a core signature lncRNA, promotes cisplatin resistance through LDHA-dependent lactylation and the formation of a regulatory axis, serving as a potential prognostic biomarker and therapeutic target for chemo-resistant osteosarcoma.
Cancer-associated fibroblasts (CAFs) are crucial for tumor microenvironment remodeling and tumor metastasis. Eukaryotic elongation factor 1 gamma (EEF1G) is aberrantly expressed in many tumors, but its role in lung cancer metastasis, particularly via exosome-mediated CAF activation, remains unclear. This study investigated EEF1G’s mechanism in lung cancer metastasis through exosome-induced tumor–stroma interactions. We performed bioinformatics analyses, single-cell RNA sequencing, and in vitro experiments (cell culture, exosome isolation, Western blot, qRT-PCR, and immunofluorescence) to characterize the function of EEF1G. A tumor-fibroblast co-culture system and in vivo metastasis models validated the EEF1G–exosome–CAF axis and associated signaling. EEF1G was overexpressed in lung cancer tissues and exosomes, which correlated with poor prognosis and CAF infiltration. EEF1G promoted the proliferation, migration, and invasion of lung cancer cells. Mechanistically, tumor cells transferred exosomal EEF1G to fibroblasts, inducing CAF transformation via the activation of the NF-κB/ROS pathway, increased mitochondrial activity, and IL-6 secretion. Subsequently, CAF-derived IL-6-rich exosomes activated STAT3 in tumor cells, enhancing invasiveness. In vivo experiments confirmed that this exosome-mediated bidirectional communication robustly facilitates lung cancer metastasis. This study elucidates a novel EEF1G exosome-mediated pathway that activates CAFs, establishing a pro-oncogenic feedback network. We emphasize the critical NF-κB/ROS/IL-6/STAT3 signaling axis in tumor–stroma interactions, offering potential therapeutic targets for lung cancer.
The nervous system is increasingly recognized as an active regulator of tumor biology rather than a passive mediator of cancer-associated symptoms. Growing evidence supports a hierarchical framework of neuro–tumor interactions encompassing chemical, structural, and electrical levels, through which bidirectional communication influences tumor initiation, progression, metastasis, and therapeutic response. At the chemical level, neurotransmitters and neuropeptides regulate tumor cell proliferation, invasion, immune modulation, and stemness. At the structural level, neurogenesis and tumor–nerve interface coupling establish physical connectivity between nerves and cancer cells. At the electrical level, synapse-like communication, defined as functional signaling between neurons and tumor cells that resembles synaptic transmission in terms of directionality and signaling dynamics, enables direct regulation of tumor behavior by neuronal activity. Neural regulation exhibits pronounced context dependency, with both tumor-promoting and tumor-suppressing effects depending on tumor type, genetic background, and microenvironmental context, as exemplified in pancreatic ductal adenocarcinoma, melanoma, and breast cancer. At the systemic level, neural circuits regulate tumor angiogenesis, metabolic reprogramming, and extracellular matrix remodeling, while also contributing to cancer-associated pain and therapy-induced neurotoxicity. Collectively, this review proposes a hierarchical neuro–tumor interaction framework that provides an integrated conceptual basis for understanding the complexity and context dependency of neural regulation in cancer biology.
INTRODUCTION:Radioresistance remains a major obstacle in the treatment of non-small cell lung cancer (NSCLC). Transcription factor AP-2α (TFAP2A) has been implicated in tumor progression, but its role in NSCLC radioresistance and translational therapeutic relevance remain unclear. METHODS:Bioinformatics analyses of TCGA and GEO datasets were used to identify transcription factors associated with NSCLC radioresponse. TFAP2A expression was evaluated in NSCLC tissues by immunohistochemistry. The functional role of TFAP2A was investigated using gain- and loss-of-function experiments in NSCLC cells, xenograft models, and patient-derived NSCLC organoids. Mechanistic studies included RNA sequencing, DNA damage repair assays, dual-luciferase reporter assays, chromatin immunoprecipitation, BRCA1 rescue experiments, and extended DNA damage response pathway validation. Structure-based virtual screening, surface plasmon resonance analysis, clonogenic survival assays, and xenograft experiments were performed to assess TFAP2A-targeted radiosensitization. RESULTS:TFAP2A was overexpressed in NSCLC tissues and was associated with poor prognosis and reduced radiotherapy response. TFAP2A knockdown enhanced radiosensitivity by reducing post-irradiation proliferative recovery, increasing apoptosis, inducing G2/M accumulation, and impairing DNA damage repair, whereas TFAP2A overexpression promoted radioresistance. TFAP2A directly bound to the BRCA1 promoter and transcriptionally activated BRCA1. BRCA1 restoration partially rescued the radiosensitizing effects and G2/M accumulation induced by TFAP2A knockdown. Extended validation of representative DNA damage response pathways and additional RNA-seq-derived repair candidates further supported BRCA1 as a principal downstream effector in this model. Patient-derived NSCLC organoids confirmed that TFAP2A knockdown enhanced radiosensitivity in a clinically derived ex vivo model. Pharmacological validation identified Dephospho-CoA as a candidate TFAP2A-binding compound that enhanced radiotherapy response in clonogenic assays and xenograft models. CONCLUSIONS:TFAP2A promotes NSCLC radioresistance by transcriptionally activating BRCA1 and enhancing DNA damage repair. The TFAP2A/BRCA1 axis may serve as a predictive biomarker and therapeutic target for overcoming radioresistance, and TFAP2A-targeted radiosensitization warrants further preclinical development.
Cervical cancer (CC) continues to pose a significant therapeutic challenge, ranking among the leading causes of morbidity and mortality in female reproductive malignancies. Cucurbitacin I (CuI), a natural compound, exhibits broad-spectrum anti-tumor activities, yet its effects and molecular mechanisms in CC remain unknown. This study aimed to investigate the anti-tumor efficacy of CuI in CC and to elucidate its underlying mechanisms. To confirm that CuI induces pyroptosis in tumor cells, gene downregulation/knockdown and selective inhibition approaches were used to comprehensively evaluate cellular morphological features, gasdermin (GSDM) protein cleavage, and the activation status of the TNF-caspase signaling pathway. Additionally, the synergistic effect of CuI in combination with cisplatin was examined through drug synergy experiments. Finally, a mouse subcutaneous xenograft model was conducted to evaluate the tumor inhibitory and immunomodulatory effects of the drug treatment. CuI effectively reduced the survival rate of CC cells. Mechanistically, CuI induces pyroptosis in cervical cancer cells, as evidenced by distinctive morphological features and GSDME cleavage. This cleavage is driven by enhanced caspase-8/3 activity downstream of TNFR1. Mechanistically, CuI activates the NF-κB pathway, which upregulates TNF-α secretion and subsequently triggers the TNFR1-caspase-8 cascade. Additionally, when combined with cisplatin, CuI enhanced pyroptosis, which in turn activated antitumor immunity and increased tumor suppression both in vitro and in vivo. CuI induces NF-κB/TNFR1/caspase-8/caspase-3/GSDME dependent pyroptosis and sensitizes cisplatin treatment in CC cells, which subsequently activates anti-tumor immune responses and contributes to tumor suppression in vivo.
Cancer stem cells (CSCs) are pivotal in driving tumorigenesis, metastasis, and resistance to multiple drugs. In this study, genes associated with stemness were identified, and the effects of GTSE1 on esophageal squamous cell carcinoma (ESCC) stemness and its underlying mechanism were elucidated. We utilized a trained stemness index model, adapted from a one-class logistic regression (OCLR) machine-learning approach, to evaluate the stemness indices of ESCC samples based on gene expression-based stemness index (mRNAsi). Subsequent algorithmic and single-cell subtype analyses confirmed the predictive capability of the mRNAsi and pinpointed GTSE1 as a potential target. Loss-of-function and gain-of-function genetic experiments were conducted to evaluate the influence of GTSE1 on ESCC self-renewal and tumor progression. Mechanistic investigations involved RNA sequencing (RNA-seq), immunofluorescence, coimmunoprecipitation (Co-IP) and so on. Additionally, the efficacy of verteporfin (a Hippo pathway inhibitor) was evaluated in vitro and vivo. The analysis of the mRNAsi in bulk RNA-seq and single RNA-seq data reveals elevated expression of GTSE1 in the high mRNAsi subgroup and clusters of highly malignant single cells. Functional studies demonstrate that the depletion of GTSE1 hinders self-renewal and progression of ESCC. Mechanistically, GTSE1 modulates the Hippo signaling pathway. GTSE1 regulates cytoskeletal tension and interacts with LATS1 to facilitate its ubiquitination and degradation, thereby reducing YAP phosphorylation and promoting its nuclear translocation. Treatment with verteporfin, significantly impairs self-renewal and progression, particularly in cells with high GTSE1 expression. This study underscores the association of GTSE1 with the stemness of ESCC, highlighting its interaction with LATS1 to regulate nuclear localization of YAP and modulate the Hippo signaling pathway. Consequently, GTSE1 emerges as a promising therapeutic target for ESCC.
Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) serve as the standard first-line therapy for advanced EGFR-mutant non-small-cell lung cancer (NSCLC). However, resistance inevitably restricts their efficacy. Although well-documented acquired resistance mechanisms have been extensively characterized, approximately 30
Triple-negative breast cancer (TNBC) patients often develop resistance to Trop2 antibody-drug conjugate (ADC), and plasmacytoid dendritic cell (pDC) dysfunction is associated with poor prognosis in TNBC, but the underlying mechanism linking these two phenomena remains unclear. The immune cell infiltration and prognosis of TNBC were analyzed through the TIMER database. Sacituzumab Govitecan (SG)-resistant MDA-MB231 cells and xenograft tumor models were established, and the function of pDC was regulated with CpG or anti-BDCA-2. The relationship between Protein arginine methyltransferase 5 (PRMT5) and immune cell infiltration was predicted by the Xiantao academic analysis. CCK-8, plate cloning, EdU and other experiments were used to detect cell functions. The functions of pDC were detected by flow cytometry and ELISA experiments. Besides, IP and IB experiments were implemented to detect the ubiquitination level of interferon regulatory factor 3 (IRF3) and the methylation level of midline 2 (MID2), and the protein interactions were verified through the Co-IP experiment. TNBC tissues resistant to SG showed reduced pDC infiltration and impaired function, associated with downregulation of IRF3. PRMT5 was highly expressed in the cytoplasm of SG-resistant TNBC cells and negatively correlated with pDC cell infiltration. PRMT5 promoted MID2 methylation to induce the ubiquitination and degradation of IRF3. Moreover, silencing PRMT5 activated pDCs, reversed CD8+ T cell suppression, and enhanced the sensitivity of drug-resistant TNBC cells to SG in vitro and in vivo. Targeting PRMT5 reshapes the immune microenvironment by restoring pDC function via the MID2-IRF3 axis, providing a promising strategy to reverse SG resistance in TNBC.
Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with limited therapeutic options, driven in part by its immunosuppressive tumor microenvironment (TME). Tumor-associated macrophages (TAMs) and neutrophils (TANs) contribute to tumor progression and immune evasion. A Disintegrin and Metalloproteinase 8 (ADAM8), a zinc-dependent protease, is strongly upregulated in PDAC and correlates with poor clinical outcomes, suggesting a regulatory role in tumor progression. Wild-type (WT) and Adam8 knockout (A8KO) PDAC cell lines were generated using the CRISPR-Cas9 technique, and PDAC mouse models with or without Adam8 expression were established to investigate the role of ADAM8 in tumor and immune cells. In vitro assays, including Western blotting, qPCR, migration and invasion assays, proliferation assays, ELISA, cytokine and proteome analyses, as well as co-culture experiments with PDAC cells and either macrophages or neutrophils, were employed to assess the effects of ADAM8 on tumor–immune cell crosstalk. In parallel, in vivo WT and A8KO KPC models were generated, genotyped, and monitored to evaluate the impact of ADAM8 on survival, tumor growth, and immune cell recruitment within the PDAC TME. ADAM8 deletion reduced tumor cell proliferation and migration, associated with reduced activation of FAK/Src/STAT3 signaling and altered secretion of cytokines including GM-CSF, M-CSF, ICAM-1, and TNF-α. Co-culture assays demonstrated that ADAM8 enhanced reciprocal signaling between tumor cells and TAMs/TANs, promoting pro-oncogenic activation. Migration assays and in vivo analyses revealed that ADAM8 facilitated recruitment of macrophages and neutrophils in PDAC TME, while Adam8KO tumors exhibited reduced immune infiltration and altered macrophage polarization. Our findings demonstrate that ADAM8 promotes PDAC aggressiveness by enhancing tumor cell proliferation and migration, activating FAK/Src/STAT3 signaling, and driving macrophage and neutrophil recruitment through cytokine regulation. By orchestrating both tumor-intrinsic pathways and tumor–immune interactions, ADAM8 emerges as a key determinant of PDAC progression and a systemic target for therapeutic intervention.
Adriamycin is a cornerstone chemotherapeutic agent for advanced breast cancer, but its efficacy is frequently compromised by chemoresistance, a process in which macroautophagy is critically involved. However, the underlying mechanisms driving this autophagy-mediated resistance remain poorly understood. Clinical data from patients with breast cancer who underwent chemotherapy were collected and the expression of MCOLN2 in tumor tissues was assessed. Using Adriamycin-resistant MCF-7/ADM cells and their parental MCF-7 cells, we investigated the role of MCOLN2 in regulating autophagic flux and mediating drug resistance. Key findings were further validated using an in vivo xenograft model. MCOLN2 expression was significantly upregulated in Adriamycin-resistant MCF-7/ADM cells and chemoresistant patient samples, where high levels correlated with poor prognosis. Knockdown of MCOLN2 sensitized MCF-7/ADM cells to Adriamycin both in vitro and in vivo, whereas its overexpression conferred resistance in parental MCF-7 cells. Mechanistically, MCOLN2 promoted autophagy, as evidenced by increased LC3-II levels and autophagosome formation. This pro-autophagic effect was mediated by MCOLN2-induced destabilization and lysosomal degradation of mTOR. Consequently, pharmacological or genetic inhibition of autophagy effectively reversed the MCOLN2-driven chemoresistance. The MCOLN2-mTOR-autophagy axis has a critical role in the development of therapeutic resistance to Adriamycin in breast cancer. Targeting MCOLN2 could be a promising therapeutic strategy to overcome Adriamycin resistance in breast cancer patients.
Despite the widespread adoption of 5-fluorouracil (5-FU)-based regimens as first-line therapy for gastric cancer, a substantial number of patients develop innate or acquired resistance, highlighting the critical need to identify its underlying molecular drivers. RPRD1B (CREPT), a gene frequently overexpressed in GC, has been clinically associated with advanced tumor stage and poor prognosis. Functionally, RPRD1B promotes aggressive tumorigenic phenotypes by accelerating cell-cycle progression, potentiating proliferative signaling, and enhancing the migratory and invasive capacities of cancer cells. However, its functional role in mediating chemotherapy resistance has not been elucidated. We established 5-FU-resistant gastric cancer cell lines (from AGS/MGC803 parents via stepwise drug exposure) to study RPRD1B’s mechanism, and developed an AAV-based system to therapeutically target RPRD1B to overcome 5-FU resistance. In this study, we demonstrated that GC patients with high tumor expression of RPRD1B (CREPT) exhibited a poor response to 5-fluorouracil (5-FU)-based chemotherapy. Furthermore, RPRD1B expression was positively correlated with the expression of TOPBP1, a critical DNA damage response and repair effector. Mechanistically, RPRD1B transcriptionally upregulates TOPBP1 by recruiting RNA polymerase II to its promoter, thereby enhancing DNA damage repair. Using an AAV-delivered shRNA to knockdown RPRD1B in a nude mouse xenograft model, we effectively overcame 5-FU resistance in gastric tumors in vivo. Our findings identify RPRD1B as a promising therapeutic target for reversing chemoresistance in gastric cancer.
Glioblastoma (GBM) remains the most lethal primary brain malignancy, characterized by profound metabolic heterogeneity and an immunosuppressive tumor immune microenvironment (TIME) that severely limits the efficacy of immune checkpoint blockade. While cuproptosis has recently been defined as a distinct form of regulated cell death driven by copper-induced mitochondrial proteotoxicity, its non-cell-autonomous roles in remodeling the immune landscape remain poorly understood. This review synthesizes emerging evidence to position cuproptosis not merely as a metabolic collapse, but as a potent driver of immunogenic cell death (ICD). We propose a potential “metabolic-immune” signaling axis wherein copper-triggered aggregation of lipoylated TCA cycle enzymes leads to mitochondrial membrane rupture and the subsequent leakage of mitochondrial DNA (mtDNA) into the cytosol. This danger signal is sensed by the cyclic GMP-AMP synthase (cGAS), activating the STING pathway to stimulate type I interferon production. We discuss how this cascade orchestrates a systemic immune response, including the recruitment of cytotoxic CD8 + T cells and the repolarization of tumor-associated macrophages from a pro-tumor M2 to an anti-tumor M1 phenotype. Furthermore, we highlight the translational potential of copper ionophores and bioengineered nanomedicines as next generation immunomodulators. By integrating copper metabolism with innate immunity, this review provides a strategic roadmap for exploiting mitochondrial stress to reverse immune exclusion and overcome therapy resistance in GBM.
Lung adenocarcinoma (LUAD) is a leading cause of cancer-related mortality worldwide, with limited treatment options due to inherent chemotherapy resistance. Ferroptosis, an iron-dependent form of regulated cell death, has recently emerged as a promising strategy to overcome this resistance. Inducing ferroptosis may sensitize LUAD cells to chemotherapy, but its molecular regulators and therapeutic potential remain largely unexplored. This study aims to investigate the role of Distal-less homeobox 6 (DLX6) in regulating ferroptosis and its contribution to LUAD progression. To elucidate the function of DLX6 in LUAD, we employed a multi-omics approach, integrating TCGA data analysis, in vitro cell culture models, and in vivo xenograft experiments. Transcriptome sequencing, chromatin immunoprecipitation (ChIP) assays, and dual-luciferase reporter assays were utilized to uncover the underlying molecular mechanisms. We found that DLX6 is significantly upregulated in LUAD and associated with poor patient prognosis. Functional studies showed that silencing DLX6 suppressed cell proliferation, triggered ferroptosis, and sensitized LUAD cells to chemotherapy. Mechanistically, DLX6 acted as a transcriptional activator of Glutathione Peroxidase 4 (GPX4), a central regulator of ferroptosis, by directly binding to its promoter region. Inhibition of DLX6 triggered ferroptosis in LUAD cells, enhancing treatment sensitivity to cisplatin. Our findings highlight DLX6 as a key regulator of ferroptosis and cisplatin sensitivity in LUAD. By promoting GPX4 expression and inhibiting ferroptosis, DLX6 plays a crucial role in LUAD progression. This study provides valuable insights into the molecular mechanisms driving LUAD and offers a potential therapeutic target for sensitizing cisplatin treatment and improving chemotherapy resistance.
