Multiple myeloma (MM) is a neoplastic disorder of plasma cells within the hematopoietic system and is characterized by osteolytic lesions. Despite significant advances, the molecular underpinnings of myeloma and its associated bone pathologies remain elusive, and there is an unmet need for effective targeted therapies. Our research uncovers upregulation of pituitary tumor-transforming gene 1 (PTTG1) in myeloma cells, which synergizes with transcription factor specificity protein 1 (SP1) to enhance its nuclear accumulation and consequently elevate the expression of glycolytic enzyme enolase-1 (ENO1). Intriguingly, ENO1, in a non-catalytic role, complexes with PTTG1/SP1, thereby amplifying the transcriptional activity of interferon regulatory factor 4 (IRF4). This cascade accelerates myeloma progression and exacerbates osteolytic lesions. Notably, IRF4 binds to the PTTG1 promoter, establishing a positive feedback loop that amplifies PTTG1 expression. Our study introduces a novel mechanistic insight into the pathogenesis of myeloma and bone deterioration and identifies disruption of the ENO1–PTTG1 interaction as a potential dual-targeting therapeutic strategy. The use of blocking peptides to interfere with this interaction demonstrates significant efficacy in curbing myeloma progression and osteolytic lesions, offering a promising avenue for clinical intervention.
Tumor hypoxia/necrosis as a hallmark of glioblastoma (GBM) is strongly associated with malignant progression and poor prognosis of GBM, however, its roles and mechanisms in the behaviors of neighboring surviving GBM cells remain poorly understood. Here, we analyzed public transcriptomic datasets to characterize gene expression in hypoxic/necrotic regions in GBM, and found that the glycolytic pathway was activated in tumor cells from these regions. Furthermore, glycolysis was also elevated in GBM cells under hypoxia/necrosis-mimicking conditions in vitro. Notably, hypoxia/necrosis-mimicking cells-derived lactate promoted the viability and proliferation and migration of neighboring surviving GBM cells. Mechanistically, lactate induced the lactylation of histone H3 lysine 9 (H3K9la), activating transcription of S-phase kinase-associated protein 2 (SKP2). This transcriptional activation was associated with H3K9la enrichment at the SKP2 promoter in GBM cells. SKP2 knockdown inhibited the tumor-promoting effects induced by lactate in GBM cells. Finally, in the orthotopic murine GBM model, hypoxia/necrosis-mimicking cells promoted GBM progression via SKP2 signaling. These results identify a hypoxia/necrosis-driven metabolic-epigenetic axis in GBM, in which lactate-mediated H3K9la promotes GBM progression through SKP2 signaling, revealing SKP2 as a potential therapeutic target for disrupting hypoxia/necrosis-associated malignancy of GBM.
Flap endonuclease 1 (FEN1), a key enzyme in DNA metabolism, exhibits oncogenic properties in various cancers. However, its functional role and underlying mechanisms in lung adenocarcinoma (LUAD) progression and tumor immunity remain poorly defined. Here, we demonstrate that FEN1 is significantly upregulated in LUAD tissues and serves as an independent prognostic factor for poor survival. Genetic depletion of FEN1 suppressed LUAD cell proliferation by inducing G0/G1 cell cycle arrest and cellular senescence, while significantly impairing migration and invasion capabilities. Mechanistically, integrated proteomic and molecular analyses revealed that FEN1 knockdown disrupts the carboxyl-terminal subunit of mucin 1 (MUC1-C)/PI3K/AKT autoregulatory loop, a critical driver of oncogenic signaling. Furthermore, FEN1 downregulation inhibited the MUC1-C/p65/ programmed death-ligand 1 (PD-L1) signaling axis, thereby alleviating tumor-mediated immunosuppression. This was evidenced by enhanced antitumor immunity, characterized by the local expansion of CD4+ T cells and restored effector function of CD8+ T cells, both in vitro and in vivo. Mechanistically, independent of its nuclease activity, FEN1 interacts with the N-terminus of eukaryotic translation initiation factor 4A3 (EIF4A3) to facilitate its binding to MUC1-C mRNA. Specifically, FEN1 is required for EIF4A3-mediated maintenance of both the transcript stability and translation efficiency of MUC1-C. Clinically, FEN1, MUC1-C, and PD-L1 are coordinately upregulated in LUAD tissues, and their co-expression predicts poor patient survival irrespective of EGFR mutation status. Our findings establish the FEN1/EIF4A3/MUC1-C axis as a novel mechanism driving LUAD progression by concurrently regulating intrinsic malignancy and extrinsic immune evasion, presenting FEN1 targeting as a promising dual-hit therapeutic strategy.
The formation of a functional skin barrier depends on terminal keratinocyte differentiation, yet the contribution of long non-coding RNAs to this process remains incompletely understood. Here, using transcriptome analysis of more than 15,000 RNA-seq samples across 54 human tissues, we identify TEDAR (Terminal Epidermal Differentiation-Associated RNA), a highly skin-enriched lncRNA. Single-molecule RNA in situ hybridization revealed that TEDAR is confined to the uppermost granular layer of the epidermis, representing an exceptionally spatially restricted expression pattern. Functional studies demonstrated that CRISPR-mediated activation of TEDAR promotes keratinocyte differentiation even in the absence of external cues, while its depletion impaired late epidermal differentiation. In three-dimensional skin equivalents, TEDAR depletion severely compromises stratum corneum formation, highlighting its importance for proper epidermal barrier assembly. Mechanistically, TEDAR associates with ERK1/2-containing complexes and restrains ERK phosphorylation, thereby facilitating the nuclear accumulation of KLF4, a key regulator of epidermal differentiation. KLF4 depletion attenuated TEDAR-induced expression of several late differentiation genes, supporting a functional TEDAR–ERK–KLF4 axis. Clinically, TEDAR expression was reduced in cutaneous squamous cell carcinoma (cSCC) and chronic inflammatory skin diseases, including psoriasis and atopic dermatitis. Moreover, IL-22 suppressed TEDAR via STAT3 signalling in epidermal models. These findings identify TEDAR as an important regulator of terminal epidermal differentiation and suggest that its suppression may contribute to disturbed differentiation in inflammatory and neoplastic skin diseases.
Aminoacyl-tRNA synthetases (AARSs) have long been recognized for their canonical role in protein synthesis, catalyzing the attachment of amino acids to their cognate tRNAs. However, accumulating evidence has revealed that many AARSs also exert non-canonical functions under various physiological and pathological conditions. Despite this, the specific contributions of AARSs to tumorigenesis remain poorly understood. In this study, we demonstrated that lysyl-tRNA synthetase (LysRS), a key member of the AARS family, is significantly overexpressed in colorectal cancer (CRC) and associated with poor prognosis. Mechanistically, LysRS undergoes reversible acetylation at K175 and K249, which regulates its ubiquitination and stability. Specifically, PCAF-mediated acetylation promotes LysRS ubiquitination and degradation, whereas SIRT1-mediated deacetylation, particularly under glucose starvation, enhances LysRS stability and increases its nuclear accumulation. Within the nucleus, LysRS physically interacts with the transcriptional coactivator PGC-1β and drives the expression of fatty acid oxidation (FAO)-related genes, including MCAD, LCAD, and CPT1A, thereby enabling metabolic adaptation to nutrient stress. Functionally, a deacetylation-mimetic LysRS mutant (2KR) enhances FAO activity, suppresses lipid droplet accumulation, and accelerates tumor growth in vivo. Importantly, pharmacological blockade of FAO largely abolished the tumor-promoting effect of the 2KR mutant in a xenograft model. Collectively, our findings uncover a previously unrecognized SIRT1–LysRS–PGC-1β axis that drives CRC progression through metabolic reprogramming, and highlight LysRS acetylation as a potential prognostic biomarker and therapeutic target in CRC.
Complete mucosal healing is a key therapeutic goal in inflammatory bowel disease (IBD). While ferroptosis-mediated epithelial cell death is known to compromise the mucosal barrier as the cornerstone of mucosal healing, the precise mechanisms driving this process during IBD pathogenesis remain to be fully elucidated. In this study, we discover that the mitochondrial metabolic enzyme 3-hydroxy-3-methylglutaryl-CoA synthase-2 (HMGCS2) expression is downregulated in the inflamed intestinal tissues of patients with IBD and in colitis mice. Intestinal epithelial-specific Hmgcs2 knockout (Hmgcs2INT-KO) accelerates colitis progression and disrupts the mucosal barrier. Hmgcs2INT-KO mice exhibit characteristic ferroptotic mitochondrial changes and elevated lipid reactive oxygen species and iron. Ketone ester (KE), the extra supplement of HMGCS2 product β-hydroxybutyrate (BHB), reverses the effects of Hmgcs2 deficiency on epithelial ferroptosis and the mucosal barrier in colitis. Mechanistically, HMGCS2 functions as a metabolic regulator that upregulates protein kinase C epsilon (PKC-ε) expression via histone H3 lysine 9 β-hydroxybutyrylation (H3K9bhb). This epigenetic event triggers the PKC-ε/YAP/TFRC axis to inhibit ferroptosis and safeguard the mucosal barrier. Thus, HMGCS2-mediated ketogenesis protects the intestinal mucosal barrier by epigenetically inhibiting epithelial ferroptosis, highlighting HMGCS2 as a promising therapeutic target in IBD.
Aging is a primary risk factor for several diseases, including neurodegenerative disorders and cancer, with DNA damage accumulation being one of the key drivers. Frailty is a severe form of aging that affects many older adults and is characterized by dysfunction across multiple body systems, leading to increased vulnerability and late-life disability. The pathogenic mechanisms differentiating frailty from healthy aging, however, remain unclear. Here, we compared the DNA damage response (DDR) in skin fibroblasts and circulating free DNA (cfDNA) levels in the blood of frail individuals with those of healthy young and elderly controls. To infer a molecular fingerprint of frailty, we also sequenced the methylated cfDNA to identify potential tissue-specific dysfunction. Frail subjects exhibited significantly higher baseline levels of DNA damage, as evidenced by increased γH2AX and 53BP1 foci in fibroblasts under basal conditions. However, no significant differences in DDR capacity were observed post-irradiation between frail and age-matched controls. Elevated cfDNA levels in frail individuals correlated with higher TNF-α levels, suggesting a link between cfDNA, inflammation, and frailty. cfDNA methylation analysis revealed an abundance of hypomethylated fragments and identified a distinctive fingerprint of differentially methylated regions that discriminated frail subjects from age-matched controls. Moreover, deconvolution analysis identified the small intestine as a potential cfDNA tissue of origin, implicating a role of this anatomical site in frailty pathobiology. Our findings provide a molecular basis for understanding frailty and its links to aging-related diseases and may open avenues for biomarker development and targeted interventions.
Metastasis and stem cell-like traits are major contributors to breast cancer lethality, yet the transcriptional mechanisms driving these processes remain poorly understood. Nuclear factor of activated T-cells 5 (NFAT5), is originally characterized as an osmoregulatory transcription factor implicated in cellular adaptation to hypertonic stress, has recently been implicated in cancer progression and invasion. However, the precise mechanisms by which NFAT5 contributes to breast cancer progression remain unclear. In this study, we investigated the role of NFAT5 in epithelial–mesenchymal transition (EMT) and stemness-associated phenotype in breast cancer cells. NFAT5 overexpression in MCF7 cells promoted EMT and mammosphere formation, whereas NFAT5 knockdown ameliorated transforming growth factor-β (TGF-β)-induced EMT, migration, and invasion. Disruption of the nuclear localization signal (NLS) in NFAT5 also inhibited TGF-β-induced EMT and reduced β-catenin nuclear accumulation. Mechanistically, TGF-β promoted NFAT5 nuclear localization and facilitated the formation of an intranuclear NFAT5/β-catenin complex. This complex enhanced NFAT5 occupancy at the E-cadherin promoter and was associated with reduced E-cadherin transcription. β-catenin depletion attenuated NFAT5 enrichment at the E-cadherin promoter and reduced nuclear NFAT5 accumulation, suggesting that β-catenin contributes to NFAT5 nuclear localization and promoter engagement during TGF-β-induced EMT. NFAT5 knockdown also reduced xenograft tumor growth and altered stemness-associated marker expression in vivo. In human breast cancer tissues, NFAT5 expression was significantly elevated and predominantly localized in the nucleus compared with adjacent normal tissues. Gene set enrichment analysis (GSEA) further showed enrichment of EMT-, stemness-, and Wnt/β-catenin-related gene signatures in NFAT5-high breast tumors. Together, these findings identify NFAT5 as a contributor to TGF-β-induced EMT and stemness-associated breast cancer progression through its interaction with β-catenin, highlighting NFAT5-associated transcriptional regulation as a potential therapeutic target in aggressive breast cancer.
Cyclin-dependent kinase 1 (CDK1), a serine/threonine kinase essential for cell cycle progression, also plays critical roles in DNA damage response, gene expression regulation, and therapeutic resistance. In this study, we identify a previously unrecognized regulatory link between CDK1 and apurinic/apyrimidinic endonuclease 1 (APE1) in non-small cell lung cancer (NSCLC). Both CDK1 and APE1 are highly expressed in lung tumors and exhibit an inverse correlation in protein expression levels across multiple lung cancer cell lines. Mechanistically, CDK1 phosphorylates APE1 at Ser54 to promote its degradation, whereas inhibition of CDK1 stabilizes APE1 protein levels and reduces the efficacy of APE1-targeted therapy. Importantly, activation of CDK1 through WEE1 inhibition using MK1775 enhances APE1 degradation and markedly sensitizes NSCLC cells to APE1 inhibition, inducing synthetic lethality. CDK1-mediated APE1 degradation mimics APE1 loss, leading to genome instability, cell-cycle dysregulation, and altered metastatic behavior. Notably, the effect of CDK1-mediated APE1 phosphorylation on cell motility is p53-dependent: in p53-proficient cells, phosphorylated APE1 activates p53-dependent programs that suppress migration and invasion, whereas in p53-deficient cells the same modification enhances metastatic potential. Furthermore, further investigation revealed that APE1 deficiency activates the cGAS–STING pathway and induces PD-L1 expression through the MAPK–ERK axis, thereby reshaping the tumor immune microenvironment and enhancing sensitivity to immune checkpoint blockade. Given the dual roles of CDK1 in APE1 regulation and immune modulation, we propose that a sequential or combinatorial strategy in which WEE1 inhibition activates CDK1 to promote APE1 degradation, priming cancer cells for APE1 inhibition and inducing synthetic lethality, while minimizing toxicity to normal cells. This approach simultaneously disrupts APE1’s endonuclease and homologous recombination repair functions and exploits CDK1-driven immune reprogramming to potentiate anti–PD-L1 immunotherapy. Collectively, our findings establish CDK1-mediated APE1 phosphorylation as a key node linking DNA repair, immune evasion, and therapeutic response, and providing a mechanistic rationale for combined CDK1–APE1–PD-L1-targeted therapy in NSCLC.
The NAD(H)/NADP(H) ratio is essential for maintaining cellular redox homeostasis. NAD kinase (NADK) is the sole cytosolic enzyme responsible for converting NAD+ to NADP+. Dysregulation of NADK has been linked to aging and cancer; however, the underlying regulatory mechanisms remain poorly understood. Here, we show that NADP+ synthesis is markedly suppressed in mice fed a high-fat diet. Mechanistically, NADK undergoes PRMT6-mediated arginine methylation at residues R39, R41, and R45, which inhibits its kinase activity and reduces NADP+ production. Mutations at these sites enhance cancer cell proliferation and tumor growth. PRMT6-dependent methylation antagonizes Akt-mediated phosphorylation to inhibit NADK activity by promoting an autoinhibitory function within its N-terminal region, thereby inhibiting NADP+ synthesis. In addition, PRMT6 can suppress NADK activity in a phosphorylation-independent manner. NADK methylation is further upregulated by the RB1/E2F pathway in response to a high-fat diet. In hepatocellular carcinoma, reduced NADK methylation elevates NADP+ levels and facilitates tumor progression. Collectively, these findings elucidate a regulatory mechanism governing NAD(H)/NADP(H) homeostasis and identify the PRMT6–NADK axis as a critical mediator of cellular adaptation to high-fat diets and increased adiposity.
Obesity and osteoporosis are two major public health concerns. Dysregulation of mesenchymal stem cell (MSC) lineage commitment has been closely linked to an imbalance between adipogenic and osteogenic differentiation, which leads to abnormal lipid accumulation and impaired bone homoeostasis. However, as the underlying mechanisms remain unclear, effective treatment options for these two tightly linked diseases are still lacking. Herein, integrin subunit β-like 1 (ITGBL1) is identified as a key regulator of the adipogenic and osteogenic lineage commitment of MSCs. ITGBL1 is downregulated in MSCs from mouse models of high-fat diet (HFD)-induced obesity and ovariectomy (OVX)-induced osteoporosis. ITGBL1 deficiency promotes the adipogenic differentiation of bone marrow-derived MSCs, adipose-derived MSCs and adipogenic precursor cells while impairing the osteogenic differentiation of bone marrow-derived MSCs and osteogenic precursor cells. Mechanistically, ITGBL1 promotes the NEDD4-mediated ubiquitination and proteasomal degradation of PPARγ. ITGBL1 deficiency stabilizes PPARγ to activate adipogenic transcriptional programs. PPARγ further undergoes reciprocal transrepression with RUNX2 in specific cellular contexts, and these transcription factors transrepress and transactivate ITGBL1 in osteogenic and adipogenic lineage precursor cells, respectively. Thus, ITGBL1, PPARγ and RUNX2 constitute an interconnected regulatory network that governs the lineage commitment of MSCs. Therapeutically, adeno-associated virus serotype 9-mediated ITGBL1 supplementation significantly alleviates obesity and/or osteoporosis in HFD-fed mice, OVX mice and systemic ITGBL1-deficient mice. Our findings reveal that ITGBL1 is crucial for maintaining the balance between the adipogenic and osteogenic differentiation of MSCs and has notable medicinal effects for the prevention and treatment of obesity and osteoporosis.
Chemotherapy remains the mainstay treatment of many solid cancers; however, resistance and recurrence compromise patient outcomes. We investigated chemotherapy resistance mechanisms in Triple Negative Breast Cancer (TNBC) by examining cells that survive chemotherapy-induced apoptotic caspase activation. Using a biosensor that permanently labels cells surviving executioner caspase activation with GFP, we identified a GFP+ population that survives transient paclitaxel treatment. These GFP+ cells display a stem-like invasive phenotype, altered mitochondrial metabolism, and increased drug resistance. Metabolomics profiling identified defects in TCA cycle metabolites and accumulation of polyunsaturated fatty acids (PUFAs). Mechanistically, surviving GFP+ cells exhibited Epithelial to Mesenchymal Transition (EMT) and ZEB1-regulated repression of GPX4 expression, resulting in increased sensitivity to ferroptotic cell death. Consistent with this, transforming growth factor- beta induced EMT also suppressed GPX4 and increased ferroptosis sensitivity in Normal Mouse Mammary epithelial cells. ZEB1 knockdown strongly reduced the GFP+ surviving fraction, identifying ZEB1 as a key regulator of apoptotic survival. Supplementation with arachidonic acid restored survival in ZEB1 knockdown cells, while the ferroptosis-protective drug, Ferrostatin-1, prevented the accumulation of GFP+ survivors, demonstrating that ferroptosis sensitivity is required for the survival of TNBC cells from chemotherapy-induced apoptosis. Together, these findings reveal a previously unrecognized link between ferroptosis and apoptosis and identify potential biomarkers and therapeutic vulnerabilities in a subset of chemotherapy-resistant TNBC.
Severe acute pancreatitis (SAP) is a life-threatening acute inflammatory disorder characterized by systemic inflammation and high mortality, for which specific targeted therapeutic strategies are still severely lacking in clinical practice. Mitochondrial dysfunction and impaired mitophagy have been validated as critical pathological drivers of SAP; nevertheless, the precise molecular targets governing the dysregulation of mitochondrial quality control remain poorly defined. Herein, we identify p38α (MAPK14) as a central regulator of mitophagy during SAP progression. Combining bioinformatic screening with an experimental SAP model, we demonstrate aberrantly hyperactivated p38α in pancreatic acinar cells. Mechanistically, activated p38α phosphorylates the S131 site of the E3 ubiquitin ligase Parkin. This site-specific phosphorylation triggers a “ubiquitination switch”, which selectively accelerates K48-linked polyubiquitination-dependent degradation of Parkin while impairing its K63-linked autoubiquitination and functional activity. Consequently, blockade of Parkin-dependent mitophagy results in accumulation of damaged mitochondria and massive leakage of mitochondrial DNA (mtDNA) into the cytoplasm, which further activates the cGAS-STING signaling cascade and exacerbates the sterile inflammatory storm. Pharmacological inhibition of p38α or genetic overexpression of the phosphorylation-deficient Parkin mutant (S131A) effectively restores mitophagic flux, eliminates cytoplasmic mtDNA accumulation, and suppresses cGAS-STING-mediated pro-inflammatory cytokine release, thereby markedly alleviating pathological injury in SAP. Our study illuminates a novel role of the p38α/Parkin/mtDNA/cGAS-STING signaling axis in the pathogenesis of SAP, and highlights targeting the p38α-mediated Parkin S131 phosphorylation switch as a promising therapeutic strategy for clinical intervention against SAP.
Alcoholic liver disease (ALD) is a global health burden with limited therapeutic options. The pathogenesis of ALD involves hepatocyte death and inflammation, but the key regulatory mechanisms remain incompletely defined. Receptor-interacting protein kinase 1 (RIPK1) is a critical signaling molecule with distinct kinase-dependent and kinase-independent, scaffold-dependent functions. While RIPK1 kinase activity has been implicated in various pathologies, the role of its scaffolding function in the liver, particularly in ALD, is unknown. Here, using hepatocyte-specific RIPK1 knockout (Ripk1-hepKO) mice, we demonstrate that loss of RIPK1 markedly aggravates ethanol-induced liver injury. In both chronic and acute-binge ethanol feeding models, Ripk1-hepKO mice exhibited significantly elevated serum transaminases, enhanced hepatocyte apoptosis, and amplified hepatic inflammation with increased macrophage infiltration, without a change in steatosis. Transcriptomic analysis revealed enrichment of inflammatory pathways in Ripk1-hepKO livers. Mechanistically, we identified endoplasmic reticulum (ER) stress as a critical contributor to this phenotype. RIPK1 deficiency was associated with attenuated NF-κB/p65 signaling, preferential amplification of eIF2α-ATF4-CHOP-associated stress responses, and enhanced CHOP accumulation, while pharmacological modulation of ER stress-associated pathways using 4-phenylbutyrate (4-PBA) or ISRIB ameliorated hepatocyte apoptosis, liver injury, and inflammation in ethanol-fed Ripk1-hepKO mice. Translating these findings to human disease, liver specimens from ALD patients showed elevated hepatocyte apoptosis, CD68+ macrophage infiltration, and induction of ER stress markers. Our study unveils a previously unrecognized protective role for the scaffold function of hepatocyte RIPK1 in ALD, positioning RIPK1 scaffolding and ER stress-associated signaling as promising therapeutic targets for ALD.
Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disorder characterized by progressive loss of motor neurons (MNs). N6-methyladenosine (m6A) is the most abundant mRNA modification, yet its role in ALS MNs degeneration remains poorly understood. In this study we observed a significant decrease in global m6A levels in the spinal cords of hSOD1G93A transgenic ALS mouse model and hSOD1G93A NSC34 cells, accompanied by reduced expression of the methyltransferase METTL3. Knocking down Mettl3 in the ALS MN model further impaired neurite outgrowth and acetylcholine release in an m6A-dependent manner. AAV-mediated Mettl3 overexpression attenuated MN loss, improved motor ability and extended survival in ALS mice. Integrated analysis based on m6A-methylome and transcriptome identified Fzd3, a WNT signaling pathway receptor gene, as a key m6A-modified target. Mechanistically, METTL3 promotes the expression of FZD3 by enhancing the stability of its mRNA through IGF2BP3. Knockdown of Fzd3 abolished the protective effects of METTL3 on neurite outgrowth and acetylcholine release in ALS MNs. Collectively, our research reveals that METTL3-mediated m6A modification on Fzd3 mRNA plays a critical role in ALS pathogenesis and highlights METTL3 as a promising therapeutic target for ALS.
TBK1 deficiency drives the pathogenesis of inborn errors of cell death (IECDs). However, the underlying cellular mechanisms remain unclear. Here, we identified a novel homozygous loss-of-function TBK1 variant resulting in exon 18 deletion (p.R621Sfs*21) that led to loss of TBK1 expression in a patient with systemic juvenile idiopathic arthritis (sJIA). The patient’s myeloid cells exhibited predominantly upregulated inflammatory responses, including TNF, NF-κB, and IFN (interferon)-γ signaling, while type I IFN responses were partially impaired in responses to agonists of pattern recognition receptors (PRRs). Analysis of the patient’s peripheral blood mononuclear cells (PBMCs) and healthy donor-derived TBK1-knockout T cells showed that TBK1-deficient cytotoxic lymphocytes are more susceptible to RIPK1-dependent cell death. Cell-cell communication analysis and combined treatment targeting TNF and IFN-γ highlighted a driving role of TNF/IFN-γ synergism in inflammatory activation of monocytes/T cells in the patient’s PBMCs, which was triggered by uncontrolled programmed cell death resulting from TBK1 deficiency. Long-term follow-up demonstrated that combined TNF and JAK inhibitor therapy was effective in suppressing the patient’s inflammatory responses. Our results identified a novel pathogenic TBK1 variant and demonstrated that cytotoxic lymphocytes are the primary drivers of aberrant cell death through a T cell-myeloid axis dependent on TNF/IFN-γ synergism. These results support combined TNF and JAK inhibition as an effective therapeutic strategy for TBK1 deficiency.
Clear cell renal cell carcinoma (ccRCC) is a common urological malignancy with limited therapeutic options for advanced disease. Aberrant DNA methylation and dysregulated ferroptosis have both been implicated in ccRCC progression, yet the mechanisms connecting these processes remain incompletely defined. Here, we identify ZBTB10 as a suppressor of ccRCC progression that transcriptionally represses GPX4, a central inhibitor of ferroptosis. Mechanistically, ZBTB10 recruits DNMT1 to the GPX4 promoter, thereby increasing promoter methylation and silencing GPX4 expression. We further define a self-regulatory ZBTB10/DNMT1/FBXW4 loop that maintains this epigenetic state. FBXW4 acts as an E3 ubiquitin ligase that promotes DNMT1 degradation and directly ubiquitinates ZBTB10 to reduce its stability. In turn, ZBTB10 recruits DNMT1 to the FBXW4 promoter, increases promoter methylation, and suppresses FBXW4 transcription. This self-regulatory circuit stabilizes both ZBTB10 and DNMT1, sustains low GPX4 expression, and promotes ferroptosis in ccRCC cells, as evidenced by increased lipid peroxidation and reactive oxygen species accumulation. Together, these findings reveal an epigenetic mechanism linking ZBTB10 to ferroptosis in ccRCC and suggest that targeting the ZBTB10/DNMT1/FBXW4/GPX4 axis may provide a therapeutic strategy for limiting ccRCC progression.
Inactivation of the Hippo signaling pathway critically contributes to hepatocellular carcinoma (HCC) tumorigenesis. However, directly targeting YAP, the key downstream effector of this pathway, has yielded limited clinical benefit in HCC. Here, we report that, in response to inflammatory stimuli, besides promoting inflammation, IKBKE inactivates YAP in liver cancer cells through direct interaction. Consequently, inhibition of IKBKE leads to elevated YAP transcriptional activity, which in turn confers resistance to IKBKE blockade. Mechanistically, IKBKE directly phosphorylates YAP, thereby blocking its nuclear translocation and promoting its degradation. As a result, IKBKE depletion sensitizes HCC cells to YAP inhibitors. Conversely, YAP blockade elevates NF-κB signaling via transcriptional induction of IKBKE, contributing to chemoresistance. Notably, combined inhibition of YAP and IKBKE synergistically suppresses tumor growth in both xenograft and C-Myc-driven HCC mouse models. Collectively, we report a bidirectional negative feedback loop between the Hippo and NF-κB pathways in liver cancer, orchestrated by the reciprocal interplay between YAP and IKBKE. This regulatory circuit supports a rational dual-drug strategy combining IKBKE inhibitors with YAP blockade for effective HCC interventions.
High-grade serous ovarian cancer (HGSOC) is characterized by early peritoneal dissemination and frequent platinum resistance, yet the epithelial states and mechanisms that couple metastasis, angiogenesis, and therapy response remain incompletely defined. We integrated in-house single-cell RNA sequencing of 82,149 cells from 21 treatment-naïve HGSOC specimens with external spatial transcriptomic and single-cell datasets to identify metastasis-associated epithelial programs. A hypoxia-enriched epithelial subcluster (E04) was preferentially expanded in advanced and metastatic lesions, showed high copy-number burden, and was defined by strong ERO1A expression. Spatial analyses and multiplex immunofluorescence showed that ERO1A-positive tumor cells were preferentially associated with endothelial niches and VEGFA-rich regions. Mechanistically, hypoxia induced ERO1A in a HIF1α-dependent manner, whereas ERO1A promoted VEGFA secretion mainly by facilitating disulfide bond-related oxidative maturation rather than by markedly increasing VEGFA transcription or total protein abundance. Functionally, ERO1A enhanced migration, invasion, angiogenesis, and cisplatin resistance in ovarian cancer cells. Clinically, high ERO1A expression was associated with shorter platinum-free interval. In orthotopic models, intraperitoneal cisplatin plus the ERO1A inhibitor EN460 produced stronger antitumor effects than either monotherapy, and VEGFA knockdown largely abrogated this additional in vivo benefit, indicating that VEGFA-dependent angiogenesis is required for the full efficacy of the combination. These findings identify a conserved hypoxia-HIF1α-ERO1A-VEGFA axis that links pro-angiogenic secretion to peritoneal metastasis and platinum resistance, and support ERO1A inhibition plus platinum as a rational therapeutic strategy in advanced HGSOC.
