Lung cancer remains the leading cause of cancer-related mortality globally. While N-glycosylation has been found to be a critical post-translational modification in multiple malignancies, the role of N-glycosylation-asso...Lung cancer remains the leading cause of cancer-related mortality globally. While N-glycosylation has been found to be a critical post-translational modification in multiple malignancies, the role of N-glycosylation-associated proteins in lung adenocarcinoma (LUAD) remains poorly defined. In this study, steroid 5α-reductase 3 (SRD5A3), a key regulator of N-glycosylation metabolism, was identified as a highly expressed molecule in LUAD, with its upregulation correlating with unfavourable patient outcomes. Functional assays demonstrated that SRD5A3 depletion markedly suppressed the proliferation, invasion, and migration of A549 and H1299 cells, thereby restraining tumour progression by triggering ferroptosis. Mechanistically, loss of SRD5A3 caused aberrant hyper-N-glycosylation of the SCARA5 protein, which impaired its interaction with ferritin light chain (FTL) and promoted FTL degradation. This process released free Fe²⁺, induced lipid peroxidation via the Fenton reaction, and ultimately, triggered ferroptosis. The glycosylation inhibitor tunicamycin reversed the ferroptosis sensitivity induced by SRD5A3 knockdown, confirming N-glycosylation as the core regulatory node. Further, site-directed mutagenesis assays revealed that the N397Q mutation of SCARA5 abolished its pro-ferroptotic effect. Collectively, these findings establish a "glycosylation-ferroptosis axis" regulatory model, uncovering a novel mechanism by which SRD5A3 modulates ferroptosis by mediating SCARA5 glycosylation.
Cancer shows aberrant alternative splicing (AS), which could functionally perturb proteins required for normal cellular behavior. Transcription factors (TFs) are proteins that regulate gene transcription. Some evidence a...Cancer shows aberrant alternative splicing (AS), which could functionally perturb proteins required for normal cellular behavior. Transcription factors (TFs) are proteins that regulate gene transcription. Some evidence about AS-driven perturbation of TFs in cancer has been documented. A systematic analysis of how cancer-specific AS could affect structural or functional characteristics of TFs is missing. Such an analysis could reveal the molecular mechanisms of cancer progression due to transcription misregulations, and thus could help identify therapeutic targets. Here, we systematically analyzed AS-induced structural and potential functional perturbations of TFs across 15 cancer types. We identified 2170 perturbed AS events (i.e., events showing significant AS pattern differences between normal and paired cancer samples) that affect 727 TFs across 14 cancer types. In 205 TFs, the perturbed AS events affect known functional domains of TFs. Additional evidence for a potential functional impact of cancer-specific AS on TFs was also found by (1) relating AS patterns of the perturbed AS events with the DNA-binding and regulatory activity of TFs and (2) using cancer dependency data to explore whether the affected TFs are essential for cancer cell line proliferation. Our findings show a large-scale, likely functional, perturbation of TFs due to cancer-specific AS.
N6-methyladenosine (m6A) is one of the most important RNA modifications and is widely distributed across mRNAs and non-coding RNAs. Its deposition, removal, and recognition are dynamically regulated by a set of proteins,...N6-methyladenosine (m6A) is one of the most important RNA modifications and is widely distributed across mRNAs and non-coding RNAs. Its deposition, removal, and recognition are dynamically regulated by a set of proteins, including methyltransferases (writers), demethylases (erasers), and binding proteins (readers). Through these regulators, m6A modifications influence key aspects of RNA metabolism, including stability, splicing, nuclear export, and translation efficiency, dynamically regulating cell fate. Protein lactylation is a reversible post-translational modification occurring on lysine residues of both histones and non-histones, with lactate or lactyl-CoA serving as the substrate. Lactylation modulates protein properties, including structure, function, and activity, thereby influencing gene expression. RNA m6A modifications and protein lactylation significantly regulate the biological behaviors of tumors, including proliferation, invasion, metastasis, metabolic reprogramming, immune evasion and treatment resistance. In recent years, their crosstalk has garnered increasing attention. On one hand, m6A regulatory proteins can be regulated by lactylation, either directly or via histone lactylation-mediated epigenetic regulation. On the other hand, m6A modifications may promote protein lactylation by regulating glycolysis and lactate production. This bidirectional interaction forms a regulatory loop that influences tumor progression. This review summarizes the emerging role of the crosstalk between RNA m6A modification and protein lactylation in tumor progression.
Kirsten rat sarcoma viral oncogene (KRAS) G12C inhibitors have demonstrated clinical efficacy against KRAS G12C-mutant non-small cell lung cancer (NSCLC); however, intrinsic and acquired resistance limit their therapeuti...Kirsten rat sarcoma viral oncogene (KRAS) G12C inhibitors have demonstrated clinical efficacy against KRAS G12C-mutant non-small cell lung cancer (NSCLC); however, intrinsic and acquired resistance limit their therapeutic potential. Therefore, combination strategies are needed to address these limitations. While various combination regimens are currently being tested in clinical trials, treatments tailored to specific biomarkers remain underexplored. In this study, intrinsic and acquired KRAS G12C inhibitor-resistant tumor cells were established using patient-derived xenograft (PDX) and mouse models. We identified that tumor cell-autocrine amphiregulin (AREG)-mediated epidermal growth factor receptor (EGFR) phosphorylation plays a pivotal role in both intrinsic and acquired resistance to KRAS inhibitors. Notably, the same resistance mechanism was observed in central nervous system metastatic recurrence in a leptomeningeal carcinomatosis mouse model. RNAscope in situ hybridization detected AREG mRNA in tumor tissues and may serve as a diagnostic tool for assessing AREG expression. Furthermore, combining KRAS inhibitors with EGFR tyrosine kinase inhibitors suppressed tumor growth, effectively overcoming resistance. Notably, high AREG mRNA expression was observed in three of nine tumor samples from patients harboring the KRAS G12C mutation, including two patients who exhibited a poor response to sotorasib and one patient who achieved a partial response. In conclusion, AREG-mediated EGFR activation is a key driver of resistance to KRAS inhibitors in patients with KRAS G12C-mutant NSCLC. Combining EGFR and KRAS inhibition represents a promising strategy to overcome therapeutic resistance and may enhance and prolong clinical benefit in patients.
The tumor microenvironment is a critical regulator of cancer progression. Histone lactylation, a novel post-translational modification, has emerged as a key player in various tumors and is closely linked to macrophage po...The tumor microenvironment is a critical regulator of cancer progression. Histone lactylation, a novel post-translational modification, has emerged as a key player in various tumors and is closely linked to macrophage polarization within the immune tumor microenvironment. Here, we delineated the signaling axis through which histone lactylation, specifically H3K18la, orchestrates crosstalk between intrahepatic cholangiocarcinoma cells and the tumor microenvironment (TME). Cleavage Under Target and Tagmentation analysis revealed an enrichment of H3K18la at the promoter of the N6-methyladenosine reader protein insulin-like growth factor-2 mRNA-binding protein 3 (IGF2BP3), enhancing its transcription. IGF2BP3 stabilizes the mRNA of the key factor secreted phosphoprotein 1 (SPP1), thereby promoting its secretion. Single-cell RNA sequencing indicated that tumor-derived SPP1 promoted intrahepatic cholangiocarcinoma (iCCA) progression by acting on macrophages via the SPP1/CD44 axis, inducing M2 polarization and migration to shape an immunosuppressive tumor microenvironment. Furthermore, using clinically relevant patient-derived organoids, xenograft models, and immunocompetent mouse models, we demonstrated that a glycolysis inhibitor synergizes with the first-line chemotherapeutic agent gemcitabine, significantly enhancing its therapeutic efficacy. These findings deliver a new exploration and important supplement of metabolic reprogramming, epigenetic regulation, and tumor immune microenvironment, and provide a new strategy for improving clinical efficacy of gemcitabine in iCCA by inhibiting histone lactylation.
Ros S, Flöter J, Kaymak I
… +12 more, Da Costa C, Houddane A, Dubuis S, Griffiths B, Mitter R, Walz S, Blake S, Behrens A, Brindle KM, Zamboni N, Rider MH, Schulze A
Matrix stiffness drives the invasion and metastasis of hepatocellular carcinoma (HCC), wherein stearoyl-CoA desaturase 1 (SCD1), as a bona fide functional downstream effector of matrix stiffness, mediates HCC cell invasi...Matrix stiffness drives the invasion and metastasis of hepatocellular carcinoma (HCC), wherein stearoyl-CoA desaturase 1 (SCD1), as a bona fide functional downstream effector of matrix stiffness, mediates HCC cell invasion and metastasis. However, the regulatory mechanism of SCD1 in response to matrix stiffness remains elusive. In this study, we identified a novel mechanism whereby F-actin cytoskeletal stress fiber assembly, triggered by increased matrix stiffness, sequesters the SCD1-targeting E3 ubiquitin ligase tripartite motif-containing protein 21 (TRIM21), resulting in reduced proteasomal degradation of SCD1 and consequently increased SCD1 protein levels, leading to HCC cell invasion and metastasis. When HCC cells were plated on soft substrates, a significant downregulation of HCC cell invasion was observed, a condition under which F-actin stress fiber disassembly released the SCD1-targeting TRIM21, leading to accelerated SCD1 proteasomal degradation and decreased SCD1 protein levels. Mechanistically, TRIM21 catalyzes K48-linked ubiquitination of SCD1 at lysine 68 (K68), resulting in proteasome-dependent degradation of SCD1, a process modulated by matrix stiffness. Genetic overexpression of TRIM21 suppresses HCC invasion and metastasis in vivo. In human HCC samples, increased collagen I content (a surrogate marker of matrix stiffness) together with TRIM21/F-actin co-localization predicted poor survival in HCC patients. Our findings reveal a new mechanotransduction pathway involving F-actin cytoskeleton stress fiber (dis)assembly, TRIM21, and SCD1 that responds to matrix stiffness mechanical signals from the tumor microenvironment to drive HCC invasion and metastasis.
Signal transducer and activator of transcription 5 A (STAT5A) modulates breast cancer cell proliferation and metastasis, yet its epigenetic regulatory mechanisms and impacts on the tumor immune microenvironment (TIME) re...Signal transducer and activator of transcription 5 A (STAT5A) modulates breast cancer cell proliferation and metastasis, yet its epigenetic regulatory mechanisms and impacts on the tumor immune microenvironment (TIME) remain unclear. Here, we explored STAT5A's epigenetic traits, metastatic roles, and effects on tumor-associated immune cells via two mouse models (immunodeficient vs. immunocompetent) with metastasis established by tail vein injection or orthotopic tumorigenesis, flow cytometry to characterize immune cell subsets, cell co-cultures, clinical tissue analyses, and dCas9-TET1CD-mediated STAT5A promoter methylation intervention. Low STAT5A expression reduced tumor cell proliferation but enhanced migration/invasion, with in vivo metastatic capacity dependent on TIME. Tumors with low STAT5A expression grew slower and metastasized less in immunodeficient mice, but exhibited opposite phenotypes in immunocompetent cohorts. Mechanistically, STAT5A downregulation was associated with epithelial-mesenchymal transition (EMT), cytokine pathway remodeling, impaired T-cell cytotoxicity, and macrophage-associated immunosuppressive remodeling. Macrophage-derived LIF activated STAT5A phosphorylation via LIFR. Clinical samples showed sequentially increasing STAT5A promoter methylation and decreasing protein expression from normal tissues to primary/metastatic tumors. dCas9-TET1CD-mediated targeted demethylation restored STAT5A expression and reduced cell migration. These findings suggest that epigenetic silencing of STAT5A contributes to breast cancer metastasis through coordinated regulation of EMT-like plasticity and the TIME, and support further investigation of STAT5A reactivation or LIF-LIFR modulation as potential anti-metastatic strategies.
Peripheral T-cell lymphoma (PTCL) is a highly heterogeneous group of lymphomas, characterized by aggressive behavior and poor outcomes. Investigating the key regulatory long non-coding RNAs (lncRNAs) is helpful to refine...Peripheral T-cell lymphoma (PTCL) is a highly heterogeneous group of lymphomas, characterized by aggressive behavior and poor outcomes. Investigating the key regulatory long non-coding RNAs (lncRNAs) is helpful to refine current prognostic models and identify novel therapeutic targets in PTCL. Using clinical and transcriptomic data from 172 patients (training cohort) and 36 patients (validation cohort) with newly diagnosed nodal PTCL, this study identified LINC01727 (also known as IRENA) as an independent prognostic marker associated with poor outcomes. Functional assays demonstrated that IRENA significantly promoted tumor growth and inhibited T-lymphoma cell apoptosis, underscoring its oncogenic role in PTCL. Mechanistically, cytoplasmic IRENA acted as a scaffold, enhancing the interactions between Rho guanine nucleotide exchange factor 1 (ARHGEF1) and Formin-like protein 1 (FMNL1), as well as their binding to RHOA. Multi-omics analysis revealed that the scaffolding activity of IRENA established a positive feedback loop, thereby provoking RHOA/MAPK activation. In the murine cell-derived xenograft model, targeting IRENA with an antisense oligonucleotide (ASO) effectively suppressed T-lymphoma growth. This study identifies IRENA as an independent prognostic biomarker for nodal PTCL patients, revealing its role in the self-organizing activation of RHOA GTPase. Targeting the IRENA/RHOA/MAPK signaling axis by ASO may represent a potential therapeutic strategy for PTCL.
CircRNAs have emerged as critical regulators in various types of cancer. Neural invasion (NI) refers to a process whereby cancer cells infiltrate into the surrounding nerves and has been shown to predict poor prognosis i...CircRNAs have emerged as critical regulators in various types of cancer. Neural invasion (NI) refers to a process whereby cancer cells infiltrate into the surrounding nerves and has been shown to predict poor prognosis in gastric cancer (GC). Accumulating evidence has suggested that tumor NI is a symbiotic relationship between cancer and nerves, which leads to the growth advantage for both. However, the involvement of circRNAs in the nerve-cancer cell crosstalk remains to be elucidated. In this study, downregulation of circSLIT2 expression was validated in GC tissues, especially in NI-positive GC tissues. Reduced circSLIT2 predicts poor prognosis in GC patients. CircSLIT2 inhibits the migration and neural invasion of GC cells both in vitro and in vivo. Mechanically, a novel peptide (SLIT2-284aa) translated by circSLIT2 was identified. SLIT2-284aa facilitates SLIT2/ROBO1 signaling via binding and inducing the ROBO1 membrane localization. Moreover, SLIT2-284aa enhances the association between ROBO1 and RhoGDI1, which suppresses RhoGDI1 phosphorylation and further reduces the release and activation of RhoA. Our work uncovers a novel circRNA-encoding peptide and a previously unknown SLIT2-284aa/ROBO1/RhoGDI1/RhoA signaling pathway that suppresses cell migration and neural invasion in GC, which provides a new prospect to understand the underlying biological mechanism of the nervous system in GC.
Tongue squamous cell carcinoma (TSCC) is an aggressive malignancy with a poor prognosis. The miR-302 family of microRNAs regulates stemness and differentiation, but its role in TSCC remains unknown. Here, we report that...Tongue squamous cell carcinoma (TSCC) is an aggressive malignancy with a poor prognosis. The miR-302 family of microRNAs regulates stemness and differentiation, but its role in TSCC remains unknown. Here, we report that miR-372-3p, miR-302c-3p, and miR-520a-3p function as potent tumor suppressors in TSCC. These miRNAs inhibited cell proliferation, clonogenic growth, and induced apoptosis in vitro and in vivo. Transcriptomic analysis revealed that miR-302 overexpression silences pro-survival and inflammatory pathways. We found that these miRNAs directly target the NF-κB subunit P65 (RELA), which is upregulated in TSCC. Knockdown of P65 recapitulated the tumor-suppressive effects of miR-302, whereas P65 reconstitution partially rescued apoptosis and growth inhibition caused by miR-302. Both P65 knockdown and miR-302 overexpression dramatically slowed tumor growth in vivo. Our results demonstrate the therapeutic potential of a novel miR-302/P65 axis that limited the progression of TSCC by regulating apoptosis and oncogenic transcription.
Circular RNAs (circRNAs) are frequently downregulated in hepatocellular carcinoma (HCC), yet the molecular underpinnings of this phenomenon remain poorly understood. Although reverse complementary matches (RCMs) are esse...Circular RNAs (circRNAs) are frequently downregulated in hepatocellular carcinoma (HCC), yet the molecular underpinnings of this phenomenon remain poorly understood. Although reverse complementary matches (RCMs) are essential for circRNA biogenesis, how their integrity is regulated in cancer has not been explored. Here, we conducted a systematic analysis correlating the expression of RNA helicases with global circRNA levels in HCC patient cohorts. MOV10 was identified as the top candidate, and its mechanism of regulating circRNAs was verified using various molecular biology approaches. The impact of MOV10 on the competing endogenous RNA (ceRNA) network was assessed through sequencing and molecular detection, and its effects on HCC cells were validated via cell biology assays, xenograft models, and clinical samples. Our findings reveal that the global downregulation of circRNAs in HCC is associated with overexpression of RNA helicases. Among these, MOV10 is significantly overexpressed in HCC, and its high expression correlates with poor patient survival. Mechanistically, MOV10 directly binds to RCMs and, through its helicase activity, disrupts the RNA secondary structures required for back-splicing, thereby reducing circRNA biogenesis. Consequently, MOV10 broadly downregulates a subset of RCM-containing tumor-suppressive circRNAs, including hsa_circ_0080210, hsa_circ_0008797, and hsa_circ_0000182, disrupting the ceRNA network and ultimately promoting HCC cell proliferation, migration, and tumor growth. Collectively, this study identifies MOV10 as a previously unrecognized master regulator of circRNA biogenesis that drives HCC progression through direct disruption of RCM-mediated circularization, offering a new perspective on post-transcriptional regulation in cancer and positioning MOV10 as a promising therapeutic target for HCC.
Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease with a dismal 5-year survival rate at 12%. The fibrotic PDAC desmoplasia is a major contributor to chemoresistance and metastasis that drive this poor prognosis...Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease with a dismal 5-year survival rate at 12%. The fibrotic PDAC desmoplasia is a major contributor to chemoresistance and metastasis that drive this poor prognosis. Cancer-associated fibroblasts (CAFs) generate PDAC tumour fibrosis and have been identified as therapeutic targets to remodel the stroma to a more drug-permissive microenvironment. We assessed the therapeutic potential of inhibiting the collagen chaperone, heat shock protein 47 (HSP47) in PDAC cells and CAFs. Collagen is a key component of PDAC fibrosis and requires the activity of HSP47 to ensure correct maturation and secretion. Herein, we show that HSP47 knockdown inhibits both PDAC cells and CAF proliferation in vitro. In vivo, therapeutic HSP47 knockdown in orthotopic PDAC tumours significantly reduced intratumoural fibrosis and opened intratumoural blood vessels, while stable HSP47 knockdown specifically in CAFs additionally reduced PDAC tumour growth. We observed that HSP47 is highly expressed in the stroma of >80% of patients in a PDAC cohort (Australian Pancreatic Cancer Genome Initiative), but that it was only prognostic of poorer overall survival in the tumour compartment. Functional relevance in the tumour compartment was further validated in 3D human PDAC explants. Our work demonstrates that HSP47 is a potential therapeutic target in both PDAC cells and CAFs and represents a robust target to interfere with tumour collagen deposition.
Tumor hypoxia drives mitophagy reprogramming to support mitochondrial quality control in non-small cell lung cancer (NSCLC) cells, yet the role of the mitochondrial cristae organizers remains poorly understood. Here, we...Tumor hypoxia drives mitophagy reprogramming to support mitochondrial quality control in non-small cell lung cancer (NSCLC) cells, yet the role of the mitochondrial cristae organizers remains poorly understood. Here, we identified MIC19, a key subunit of mitochondrial contact site and cristae organizing system complex, as an essential regulator of hypoxia-induced mitophagy in NSCLC. We demonstrate that prolonged hypoxia induces MIC19 protein expression in a HIF-1α-dependent manner and that elevated MIC19 promotes NSCLC cell proliferation and metastasis. MIC19 sustains mitochondrial morphology and mitophagy activation under hypoxic stress. Mechanistically, HIF-1α transcriptionally upregulates NMT1, an N-myristoyltransferase that catalyzes N-myristoylation at Gly2 of MIC19 protein, which is essential for the mitochondrial localization and protein stability of MIC19. MIC19 facilitates PRKN-dependent K48-linked ubiquitination of the outer mitochondrial membrane protein voltage-dependent anion channel 2 (VDAC2), thereby promoting mitophagy progression under hypoxic stress. Therapeutically, suppression of MIC19 via shRNA combined with pharmacological inhibition of autophagy using chloroquine synergistically impairs NSCLC tumor growth in vivo. Collectively, these findings uncover a previously unrecognized HIF-1α-NMT1-MIC19-VDAC2 axis that drives hypoxia-adaptive mitophagy and reveals a potential therapeutic vulnerability in hypoxic NSCLC.
Dysregulation of Speckle-type POZ protein (SPOP) and cargo receptor p62/SQSTM1 impairs homologous recombination (HR)-mediated DNA repair by destabilizing RAD51 and FLNA, yet their mechanistic interplay in genomic stabili...Dysregulation of Speckle-type POZ protein (SPOP) and cargo receptor p62/SQSTM1 impairs homologous recombination (HR)-mediated DNA repair by destabilizing RAD51 and FLNA, yet their mechanistic interplay in genomic stability and oncogenesis remains unclear. In this study, we found that the interaction between SPOP and p62/SQSTM1 is obviously enhanced in nucleus in response to DNA damage. Moreover, the nuclear ubiquitination of p62/SQSTM1 at lysine 7 by SPOP led to its degradation, resulting in upregulation of RAD51 and FLNA, RAD51 foci formation, and HR efficiency. In addition, patients-derived p62/SQSTM1 mutations in SPOP-binding consensus (SBC) motif (S276Y/S277G/S277I) increased radiotherapy sensitivity in vitro and in vivo, which attributes to HR deficiency caused by increased degradation of RAD51 and FLNA proteins, and decreased RAD51 and γ-H2AX foci formation. Our finding provides insight into the regulation of HR by SPOP and p62/SQSTM1, and disrupting the interaction between SPOP, p62/SQSTM1 and nuclear ubiquitination may be a potential approach for overcoming radiotherapy resistance in cancer.
Ye Q, Liu HZ, Wang XQ
… +16 more, Hu LP, Li H, Gong SZ, Tao YT, Wu Z, Liu WW, Han F, Zhu L, Li DX, Zhang XL, Jiang SH, Zhang ZG, Huo YM, Wo Q, Peng QL, Yang XM
Cellular adaptive volume regulation is essential for maintaining metabolic homeostasis and supporting survival, yet its role in desmoplastic pancreatic ductal adenocarcinoma (PDAC) remains incompletely understood. Throug...Cellular adaptive volume regulation is essential for maintaining metabolic homeostasis and supporting survival, yet its role in desmoplastic pancreatic ductal adenocarcinoma (PDAC) remains incompletely understood. Through comprehensive bioinformatic and functional studies, we identified LRRC8A, the core subunit of volume-regulated anion channels (VRAC), as a central regulator linking volume homeostasis to PDAC progression. Beyond its established role in osmotic stress responses, genetic silencing or pharmacological inhibition of LRRC8A revealed its critical function in proliferation-associated volumetric expansion during S-phase. Functional validation through in vitro proliferation assays, in vivo xenograft models, and patient-derived pancreatic cancer organoids (PDO) demonstrated that LRRC8A critically drives PDAC progression. Mechanistically, LRRC8A coordinates plasma membrane dynamics, cortical cytoskeletal organization, membrane-delimited oncogenic signaling (KRAS/EGFR), and nucleolar ribosome biogenesis to support volumetric expansion during S phase. Co-immunoprecipitation coupled with mass spectrometry identified that LRRC8A forms complexes with Caveolin 1 (CAV1). Disruption of LRRC8A leads to decreased CAV1 protein levels, impaired activation of KRAS and EGFR oncogenic signaling, and suppressed ribosome biogenesis and global protein synthesis. Reciprocally, CAV1 knockdown or cholesterol depletion using lovastatin destabilized LRRC8A in plasma membrane, resulting in reduced cortical F-actin organization, oncogenic signaling and biosynthetic activity, indicating that LRRC8A and CAV1 are mutually stabilized and depend on cholesterol-rich membrane microdomains for proper integration and function. Furthermore, disruption of LRRC8A-CAV1 axis through LRRC8A inhibition or cholesterol depletion potently suppressed PDO growth in vitro. Collectively, our work establishes the LRRC8A-CAV1 complex as a key coordinator of biosynthetic expansion and a promising therapeutic target in pancreatic cancer.