Cancer Discovery

Oncogenic KRAS drives >90% of pancreatic ductal adenocarcinoma (PDAC), and the pan-RAS inhibitor daraxonrasib doubles overall survival, but adaptive and acquired resistance limit the depth and duration of responses. To systematically map combination vulnerabilities, we developed RAS+, a digenic CRISPR knockout library testing 10,296 pairwise perturbations across oncogenic signaling pathways, and screened 12 cell lines, revealing genotype- and lineage-specific interactions. In KRASmut PDAC, the most differentially effective gene pair was KRAS and FRS2, an adapter coupling FGFR signaling to RAS. Combined KRAS/pan-FGFR inhibition was synergistic and cytotoxic, eradicating tumor cells and overcoming resistance in vitro and deepening and prolonging regressions in vivo. Single-cell analysis identified cancer-associated fibroblasts (CAFs) as a primary source of FGF ligands in PDAC, and CAF conditioned media or individual FGFs promoted resistance. These findings define a stroma-to-tumor adaptive FGFR circuit limiting the effects of KRAS inhibition. Thus, combined KRAS/FGFR blockade may be a strategy to improve responses.

Homologous recombination deficiency (HRD), most commonly arising from BRCA1/2 loss, is accompanied by metabolic remodeling whose contours and therapeutic implications remain poorly defined. Through pan-cancer analysis of 10,619 tumors from The Cancer Genome Atlas (TCGA) and isogenic BRCA1/2-deficient models, we show that HRD tumors display broad metabolic rewiring, with consistent alterations in glucose metabolism. Unexpectedly, BRCA1/2 loss is associated with selective upregulation of the constitutively active glycolytic enzyme Pyruvate Kinase M1 (PKM1) isoform, contrasting with the PKM2-dominant state of most cancers, and produces an elevated pyruvate kinase activity state. Overactivating PKM, with small molecules activators, including the FDA-approved drug mitapivat, triggers superoxide accumulation, disrupts PINK1-dependent mitochondrial quality control, induces DNA damage, and selectively kills BRCA2-deficient tumors in vivo, while sparing BRCA2-proficient counterparts. These findings recast HRD as a metabolic state and identify PKM activation as a candidate therapeutic strategy for biomarker-selected HR-deficient cancers.

Surgical decisions for intraductal papillary mucinous neoplasms (IPMNs), precursors of pancreatic cancer, depend on distinguishing low- from high-grade dysplasia, a distinction that molecular markers could refine. We microdissected 433 tumor regions from 135 patients and integrated transcriptomics, deep-learning histology, and KRAS/GNAS RNA-called variants. RNA programs and morphological motifs separated lesions by phenotype, intestinal versus others, rather than by dysplasia grade. Along gastric IPMN trajectories, low-grade lesions recapitulated the pit-chief polarity of normal gastric glands, whereas high-grade lesions were indistinguishable from pancreatobiliary lesions in morphology, RNA programs, and driver mutations. Intestinal IPMNs arose through two routes: a canonical GNAS-associated pathway and a KRAS-associated shift from low-grade gastric features, with lesions sharing driver mutations retaining common programs across phenotypes. Resolving these phenotypic trajectories clarified distinct progression paths and enabled phenotype-specific prediction of high-grade dysplasia in mucus aspirated from 94 resected lesions. These findings support a promising fluid-based assessment of IPMN status.

Loss of the Y chromosome (LOY) has been largely unexplored in pancreatic ductal adenocarcinoma (PDAC), and no mechanistic framework previously explained its role in tumor biology. We identify LOY as a recurrent, functionally consequential alteration affecting ~50% of male PDAC patients across two independent cohorts, with strong enrichment in advanced disease and, critically, in the basal subtype, establishing LOY as a clinically actionable biomarker. Comprehensive genomic profiling positions LOY as a distinct genetic event associated with TP53 mutations, implicating it in aggressive tumor evolution. Integrative analyses across bulk tumors, single-cell datasets and CRISPR-engineered PDAC models converge on epithelial-to-mesenchymal transition (EMT) as the dominant LOY-driven program. Y-chromosome deletion alone induces EMT transcriptional states, mesenchymal morphology and enhanced metastatic ability. Mechanistically, LOY disrupts epigenetic regulation through loss of Y-linked chromatin modifiers, reshaping DNA methylation at EMT- and basal-defining loci and reducing chemotherapy sensitivity. These findings establish LOY as a causal genetic driver of PDAC progression and a clinically accessible biomarker with direct therapeutic relevance.

Acute myeloid leukemia (AML) remains limited by high relapse rates and a scarcity of biomarker-directed therapies, underscoring the need to identify actionable vulnerabilities and mechanisms of therapeutic resistance. O6-methylguanine-DNA methyltransferase (MGMT), a DNA repair enzyme that directly reverses mutagenic O6-alkylguanine lesions, is epigenetically silenced in multiple cancers. Although MGMT silencing is predictive of temozolomide (TMZ) response in glioblastoma with significant survival advantage, prior clinical trials of TMZ in AML have shown only modest responses. Therefore, the prevalence and therapeutic relevance of MGMT silencing, as well as genetic factors that modify its therapeutic response in AML, remain to be comprehensively investigated. Here, we first profiled MGMT status across a diverse cohort of 23 de novo and 16 relapsed/refractory (R/R) primary AMLs using an integrated analysis of MGMT mRNA expression, promoter methylation, and protein expression. We found that approximately 25-30% of AMLs harbor MGMT silencing, in contrast to consistent MGMT expression in healthy CD34+ hematopoietic stem and progenitor cells. We further identified frequent loss of mismatch repair (MMR) proteins in these AML cohorts, a known resistance mechanism against TMZ in glioblastoma. Using CRISPR knockout screening and genetically engineered AML models, we found that MMR loss also drives both upfront and acquired TMZ resistance in MGMT-silenced AML. These findings identify MMR deficiency as an important and previously underappreciated genetic contributor to the modest responses observed in prior trials of TMZ in AML. To therapeutically exploit MGMT silencing while bypassing genetic determinants of resistance, including MMR deficiency, we evaluated clinically and preclinically characterized MGMT-dependent DNA-alkylating agents and identified a fluoroethylating analog of TMZ, N3-(2-fluoroethyl) imidazotetrazine (KL50), with pronounced and selective activity in MGMT-silenced AML. KL50 retained antileukemic activity irrespective of MMR status, significantly prolonging survival in humanized MISTRG6 mice harboring primary AML patient-derived xenografts. Mechanistically, KL50 induced DNA damage through the time-dependent formation of interstrand DNA crosslinks, bypassing MMR dependence and triggering a replication stress response dominated by ATR signaling. Pharmacologic ATR inhibition synergized with KL50, producing marked antileukemic activity and significantly extending survival across AML models without compromising hematologic safety. Together, these findings establish MGMT silencing as a prevalent and therapeutically actionable biomarker in AML, define MMR status as a key determinant of TMZ response in AML but not KL50 sensitivity, and provide a translational rationale for combining low-dose O6-fluoroethylating imidazotetrazines with ATR inhibitors to target both de novo and R/R AML across diverse genetic backgrounds.

Pancreatic ductal adenocarcinoma (PDAC) progression involves malignant cell state plasticity. Epigenetic changes underlie this plasticity, yet the PDAC cis-regulatory landscape remains understudied. To address this, we profiled 33 primary tumors and 7 metastases from 39 patients with single-cell ATAC-seq, paired with 10 single-cell RNA-seq profiles. We found that epigenetic GATA6+/KRT17+ co-accessibility identifies a classical-basal subtype-intermediate progenitor state (SIP) associated with better clinical outcomes. SIP cells display limited epigenetic reprogramming from premalignant epithelium and retain gastric-intestinal differentiation reminiscent of neoplastic precursors. Lineages without GATA6+/KRT17+ co-accessibility exhibit greater lineage and epithelial-mesenchymal plasticity. Classical PDACs that repress basal gene accessibility activate neural-like progenitor (NRP) and tuft lineage enhancers, whereas basal committed tumors display esophageal transdifferentiation. Compared to SIP, classical-NRP and basal committed tumors have poorer outcomes, and show distinct PD-1/PD-L1 immune proteomic phenotypes and prognostic myofibroblast epigenetic states, respectively. Our work reveals links between lineage reprogramming, EMT, and epigenetic progression in human PDAC.

MLL/KMT2A amplifications and rearrangements are prevalent in infant, adult, and therapy-induced leukemia; however, the molecular contributors controlling these alterations remain elusive. Here, we reveal that rapid CTCF degradation generates local genome structure alterations at KMT2A and copy gains and rearrangements. We then established a conserved, coordinated interplay between DNA and histone methylation pathways that control CTCF occupancy, and in turn, KMT2A locus stability. For example, DNMT1 overexpression promotes increased H3K9 methylation, reduced CTCF occupancy, and causes KMT2A alterations. However, DNMT1 inhibition suppresses these events and KMT2A alterations caused by topoisomerase II inhibition. Locus-specific epigenome targeting demonstrated that DNA or H3K9 methylation promotes KMT2A copy gains and rearrangement, whereas targeted TET activity suppresses these events upon methylation perturbation or doxorubicin treatment. These findings identify a conserved, coordinated DNA-histone methylation axis governing KMT2A amplifications and rearrangement susceptibility, revealing biomarkers and therapeutic targets to predict and intercept these events in cancer.

Bispecific T cell engagers (BTCEs) have transformed the treatment of B cell malignancies, but how they remodel non-conventional T cell circuits in patients, and how they should be ideally combined with existing treatment backbones, remains unclear. Here we show that CD3-engaging BTCEs convert human FOXP3 regulatory T cells (Tregs) into an AP-1-imprinted hybrid cytotoxic state that contributes to tumor clearance. Leveraging longitudinal bone marrow and peripheral blood sampling from patients with newly diagnosed multiple myeloma (NDMM) treated with BTCE-based induction in the phase 2 (GMMG-HD10/DSMM-XX/MajesTEC-5) trial, which achieves uniformly deep, minimal residual disease (MRD)-negative remissions, we integrate single-cell RNA, ATAC and TCR sequencing with functional and metabolic profiling to define the underlying mechanism. BTCE-containing induction drives expansion of cytotoxic CD8 clones and the emergence of a Treg population characterized by GZMA, GNLY and NKG7 expression, enriched cytotoxic gene signatures, and licensed by BATF-AP-1-centered chromatin remodeling. In vitro, BTCE-exposed Tregs acquire bona fide lytic function, killing tumor cells in a target- and dose-dependent manner and undergoing metabolic rewiring towards an effector-like state while retaining canonical Treg lineage markers. Immunomodulatory drugs (IMiDs) do not initiate but quantitatively amplify and qualitatively reshape this BTCE-driven cytotoxic program, providing a mechanistic rationale for BTCE-IMiD combination regimens. Cytotoxic Treg reprogramming is conserved across BTCEs targeting BCMA, GPRC5D, and CD19 and across multiple myeloma, as well as acute lymphoblastic leukemia. These findings reveal unexpected plasticity of human Tregs under synthetic T cell engagement and establish cytotoxic Tregs as active effectors, candidate biomarkers and tractable levers for optimizing T cell-redirecting immunotherapy.

Therapeutic inhibition of the RAS/MAPK cascade, an oncogenic driver in over one-third of human cancers, has been limited by a core trade-off: effective pathway blockade in tumors versus dose-limiting toxicity in normal tissues. Although Type 1.5 RAF inhibitors successfully mitigated this trade-off in BRAF-monomer-driven tumors, an equivalent strategy has been lacking for RAF-dimer-driven cancers, including those with RAS mutations. Here, we characterize ELV-3111, a next-generation, potent, and selective Type 1 RAF inhibitor that overcomes this limitation via a distinct mechanism of action. ELV-3111 induces paradoxical MAPK hyperactivation in normal tissues by binding RAF and promoting the active conformation (priming) followed by rapid dissociation (fast off-rate), a biochemical feature that spares RAS-mutant tumors, where RAF is already primed. In these and other RAF dimer-driven tumor models, ELV-3111 achieves potent and selective MAPK and growth suppression. When combined with a MEK inhibitor, ELV-3111 enables complementary pharmacology: additive inhibition in tumors and compensatory effects in normal tissues. The combination produced durable regressions across RAS-mutant and BRAF-mutant models, including a RAS-mutant model refractory to current therapies, while maintaining favorable tolerability. Thus, we uncover a generalizable mechanism that enables Type 1 RAF inhibitor plus MEK inhibitor combinations to achieve tumor-selective MAPK suppression, with the potential to inform targeted therapy design.

Despite the remarkable success of immune checkpoint blockade (ICB), durable clinical benefit remains limited to a subset of patients, highlighting the need for predictive biomarkers and new therapeutic targets. Here, we investigated the early immune dynamics associated with anti-PD1 responsiveness using longitudinal single-cell transcriptomics, spatial transcriptomics, and neutrophil-specific genetic perturbations in preclinical models of triple-negative breast cancer. We identified a conserved neutrophil interferon-stimulated gene (ISG) program that emerges before overt tumor divergence and predicts resistance to anti-PD1 therapy. Successful treatment was associated with an early reduction of IFN-responsive neutrophils in both blood and tumor tissues, whereas persistent neutrophil IFN signaling correlated with therapeutic resistance. Mechanistically, genetic disruption of either type I or type II interferon signaling in neutrophils enhanced anti-PD1 efficacy and promoted durable anti-tumor immune memory. Spatial analyses further revealed an inverse association between IFN-responsive neutrophils and tertiary lymphoid structure-enriched regions during effective therapy. Together, these findings identify IFN-responsive neutrophils as early determinants of immunotherapy outcome and establish dynamic neutrophil interferon programs as candidate blood-based biomarkers and therapeutic targets for cancer immunotherapy.

Tumor heterogeneity is a major determinant of tumor progression and therapeutic resistance, yet the contribution of metabolism to intratumoral heterogeneity still remains poorly explored. Here, we find that pyruvate dehydrogenase kinase-1 (Pdk1) expression defines metabolically distinct cancer cell populations in colorectal tumors. Image-based spatial single-cell phenotyping shows that Pdk1-high cells are associated with tumor progression in orthotopic models of colorectal cancer (CRC). Genetic ablation experiments demonstrate the role of Pdk1-high cells in tumor growth, 5-fluorouracil chemoresistance and tumor relapse. Mechanistically, we identify a link between Pdk1-driven metabolic states and specific cell phenotypes, where Pdk1-high cancer cells exhibit an EMT, stem cell-like phenotype characterized by increased interferon (IFN) signaling. Mitochondrial remodeling in Pdk1-high cells leads to the release of mitochondrial DNA to the cytosol and activation of IFN pathways, promoting Pdk1-driven phenotypes. Inhibition of IFN signaling impairs the tumorigenic and aggressive features of Pdk1-high cancer cells, thus establishing a functional connection between metabolic heterogeneity, cell-intrinsic IFN signaling and aggressive CRC.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive cancers, in part due to a dense and highly plastic tumor microenvironment dominated by cancer-associated fibroblasts (CAFs). In previous work, we identified a CAF population expressing a neural-associated NES+SOX4+NOTCH1+ program that increased with disease progression. The signals driving this state and the mechanisms regulating it remained unclear. Here, we investigated how tumor-derived signals activate this program and whether it represents a stable fibroblast identity or a reversible state. Using spatial transcriptomic data spanning normal pancreas to invasive carcinoma, we identified EGF, FGF2 and BDNF as candidate tumor-to-fibroblast signals associated with disease progression. Functional experiments in patient-derived CAFs and human fibroblast cell lines showed that EGF and FGF2 are sufficient to induce the NES+SOX4+NOTCH1+ program. Growth factor withdrawal reversed the NES+SOX4+NOTCH1+ program at both the protein and transcriptional levels, indicating that this state is dynamic and environment dependent. Single-cell transcriptomic analysis further revealed a multi-phase response involving early loss of fibroblast-associated features, transient activation of neural-associated genes, and a later stress-associated state. Regulatory analyses identified ETS-family transcription factors as key regulators of the program, while phosphoproteomic profiling and inhibitor studies showed that MAPK/ERK signaling plays a central role in its transcriptional activation. Finally, pan-cancer single-cell analysis showed that this state is enriched in CAFs and increases from normal to tumor tissue across multiple cancer types. Together, these findings define a reversible, growth factor-driven CAF program and identify signaling mechanisms that may provide opportunities to selectively modulate tumor-supportive fibroblast states.

NECTIN4 is the target of enfortumab vedotin (EV), but its biological role in bladder cancer (BC) and its relationship to EV plus PD-1 blockade remain unclear. Integrating clinical multi-omics, spatial and single-cell immune profiling, and experimental models, we identify NECTIN4 as a subtype-dependent determinant of tumor state and antitumor immunity. In basal BC cells, NECTIN4 suppressed inflammatory and mesenchymal programs. Consistently, NECTIN4-high basal/squamous muscle-invasive BCs showed favorable survival, higher checkpoint inhibitor response rates, and a coordinated CD8+ T cell-inflamed microenvironment with no comparable associations in luminal papillary tumors. In orthotopic models, murine Nectin4 promoted CD8+ T cell-dependent tumor control, whereas human NECTIN4 conferred EV sensitivity. EV also attenuated NECTIN4-dependent TIGIT binding. Conversely, NECTIN4-low models were preferentially sensitive to HDAC inhibition. NECTIN4 therefore couples antibody-drug conjugate targetability to a subtype-specific tumor-immune state permissive for checkpoint blockade, whereas the NECTIN4-low state defines a distinct inflammatory-mesenchymal state with an alternative therapeutic vulnerability.

Treatments for pancreatic ductal adenocarcinoma (PDAC) often fail because of the cancer's ability to adapt its signaling and metabolic pathways to circumvent treatment mechanisms. PDAC hallmarks that promote treatment resistance (increased fatty acid metabolism, survival signaling, desmoplasia, and macropinocytosis) are extensively regulated by heparan sulfate proteoglycans (HSPGs) and their binding partners. The pro-tumor functions of HSPGs are controlled by site-specific cleavage of their heparan sulfate chains by mammalian heparanase; however, cleavage by bacterial heparinase III (HepIII) represses these functions and prevents downstream, pro-tumor signaling. Using tumor-targeting, attenuated Salmonella typhimurium (strain YS1646), we have limited HepIII transgene expression to tumor tissue. Degradation of tumor cell heparan sulfates by HepIII resulted in decreased macropinocytosis, reduced survival signaling, lipid storage depletion, and decreased expression of translational machinery. This tumor-targeting treatment has the potential to improve the efficacy of several approved pancreatic cancer therapies, which is predicted to increase patient survival.

KRAS is mutated in over 90% of pancreatic ductal adenocarcinoma (PDAC) and is required for tumor initiation and maintenance. While clinical trials testing mutant-selective and pan-RAS inhibitors (KRASi) have demonstrated significant clinical benefit, genetic and non-genetic mechanisms of resistance limit the long-term efficacy of monotherapy strategies. Here, we used quantitative temporal analysis of the global, phosphorylation, and surface proteome to comprehensively identify non-genetic adaptive pathways and cell surface biomarkers in response to acute and long-term KRAS inhibition in PDAC. Through integrative machine learning analysis of the KRASi-proteome and publicly available datasets, we discovered top priority cell surface targets for combination therapy with KRASi. We identified Placental Alkaline Phosphatase (ALPP) as upregulated in response to KRASi through compensatory JAK2/STAT3 signaling. We developed a novel clinical grade ALPP/ALPPL2 (ALPG)-targeting antibody drug conjugate (ADC) with site-specific MMAE conjugation and demonstrated single agent efficacy in PDAC models, as well as enhanced internalization and anti-tumor efficacy in combination with KRASi. Together, these studies comprehensively define the KRASi-induced proteome and identify ALPP/ALPPL2 as a promising cell surface target for combination with KRASi to enhance response and forestall KRASi resistance.

Supratentorial ependymomas (ST-EPNs) are aggressive pediatric brain tumors predominantly driven by the recurrent ZFTA-RELA fusion, an oncogenic chromatin regulator that establishes an aberrant transcriptional program. Although metabolic pathways modulate epigenetic regulation by controlling the availability of metabolic cofactors, how ZFTA-RELA coordinates metabolic reprogramming with epigenetic regulation is not well understood. Here, we show that ZFTA-RELA-positive ependymomas exhibit enhanced methionine dependency, elevated adenosyl homocysteinase (AHCY) expression, and epigenetically control aspartate metabolism for tumor growth. Mechanistically, ZFTA-RELA upregulates AHCY, increasing cellular methylation potential which promotes H3K4me3-dependent expression of CAD, the first enzyme complex of de novo pyrimidine biosynthesis, while simultaneously enforcing H3K27me3 mediated repression of ASNS, which encodes asparagine synthetase. Through this coordinated epigenetic program, aspartate utilization is directed toward pyrimidine biosynthesis while endogenous asparagine production is limited. Restricting S-adenosylmethionine availability or genetically or pharmacologically inhibiting AHCY reverses these epigenetic states, leading to CAD downregulation, ASNS upregulation, impaired nucleotide synthesis, and suppression of tumor growth in vitro and in vivo. Similarly, EZH2 inhibition also restores ASNS expression and suppresses tumor proliferation. These findings suggest that ZFTA-RELA EPN maintain ASNS-low phenotype which conditionally make them dependent on extracellular asparagine. We further show that enhanced de novo pyrimidine synthesis not only supports nucleotide production but also provides UDP-sugars required for N-glycosylation and stabilization of the asparagine transporter SLC1A5, thereby promoting extracellular asparagine uptake and tumor proliferation. Collectively, our findings identify AHCY as a critical metabolic regulator of epigenetic and metabolic reprogramming that drives pyrimidine synthesis and establishes extracellular asparagine dependency, revealing actionable metabolic vulnerabilities in ZFTA-RELA-positive ST-EPNs.

High-grade serous ovarian cancer progresses within a lipid-rich ascites microenvironment that engages stress-adaptation programs supporting malignant growth, yet how failed stress resolution influences tumor progression remains incompletely defined. Here, we show that unresolved lysosomal stress restrains tumor progression by sustaining tumor cell-intrinsic STING activity and reorganizing antitumor immunity. We identify BLTP3A as a lysosomal stress-resolution factor in ovarian cancer and show that the common germline missense variant BLTP3A M1098T increases stress-induced lysosomal damage. Patients carrying M1098T had longer overall survival and tumors enriched for cytotoxic T cell-myeloid neighborhoods. In syngeneic tumors, Bltp3a loss or orthologous variant expression delayed progression and generated Cxcl9+ antigen-presenting macrophage niches; M1098T-expressing human tumors similarly promoted interferon-responsive myeloid and T-cell enrichment in humanized mice. Mechanistically, ascites-induced lysosomal stress activated a STING-ATF4-BLTP3A feedback program. BLTP3A dysfunction disrupted CASM-associated lysosomal stress resolution, resulting in prolonged STING activity and sustained tumor-derived IFN-{lambda} without increased cGAMP. Tumor-cell STING and IFN-{lambda} were required for immune remodeling and tumor control. Thus, BLTP3A-dependent lysosomal stress resolution constrains the persistence of stress-induced STING signaling, whereas failure of this response sustains a tumor-intrinsic inflammatory program that organizes protective antitumor immunity.

Cancer cell plasticity underlies tumor progression, metastasis and therapeutic resistance, yet how RNA-binding proteins regulate malignant state transitions remains poorly defined. Here, we identify the splicing regulator RBFOX2 as a suppressor of oncogenic cell plasticity in Group 3 medulloblastoma (MB). OTX2 antagonizes RBFOX2 by directing an opposing alternative splicing program that mirrors developmental origins and controls cytoskeletal dynamics and cell state transitions. Mechanistically, OTX2 alters the RBFOX2 RNA-binding landscape, limiting RBFOX2 engagement at cytoskeletal loci and suppressing exon inclusion. RBFOX2 loss rewires splicing and transcriptional outputs to promote highly plastic proliferative, mesenchymal-like and undifferentiated cellular states associated with enhanced oncogenic properties. Consistent with these findings, RBFOX2low states mark highly plastic cell populations in patient tumors and xenografts, positioning RBFOX2 as a determinant of malignant cell stability. Together, these findings establish RBFOX2 as a developmental gatekeeper that restrains malignant cell plasticity through coordinated control of cytoskeletal gene programs.

Translation reprogramming is central to cancer cell plasticity under stress. However, the molecular players coordinating translation and epitranscriptomic rewiring to determine adaptive responses to mitotic stress remain elusive. Here, we found that microtubule targeting agent (MTA)-induced CDK1 blocks global translation while it phosphorylates and degrades TACC3, a multifunctional adaptor, releasing eIF4A/eIF4E/eIF4G2 initiation factors. This promotes selective m7G cap-dependent translation of mRNAs with MTAup motif that are functionally required for apoptosis by disrupting proteostasis, promoting MTA-sensitivity. On the other hand, selectively translated TACC3 interacts with eIF3d/eIF4G1 and the m6A writer METTL3, mediating switch to m6A methylation and m7G cap-independent translation of mRNAs with hnRNPC-motif involved in chromosome segregation, driving MTA tolerance. TACC3 inhibition overcomes MTA resistance via restoring translation reprogramming. These findings demonstrate that TACC3 is a pivotal coordinator of translation/epitranscriptomic reprogramming and a therapeutic target in MTA-refractory cancers.

Lactate uptake through monocarboxylate transporter 1 (MCT1) is associated with aggressive disease in non-small cell lung cancer (NSCLC), but how lactate transport supports tumor metabolism remains incompletely understood. Integrating stable isotope tracing, metabolomics, and transcriptomics across patient tumors, animal models, and cultured cells, we show that elevated lactate utilization and SLC16A1 expression correlate with worse clinical outcomes in NSCLC. Although MCT1 inhibition with AZD3965 does not significantly impair tumor growth as a monotherapy, it depletes purine-associated metabolite pools, alters redox balance, and induces a conserved transcriptional response involving MYC target dysregulation and suppression of nucleotide metabolism genes. Addition of exogenous hypoxanthine, or expression of the E. coli-derived NADH-producing enzyme soluble transhydrogenase, partially rescues the effects of MCT1 inhibition. Importantly, this metabolically compromised state sensitizes NSCLC to nucleotide-targeting chemotherapies, including pemetrexed. These findings reveal that MCT1 mediated lactate uptake sustains nucleotide homeostasis in NSCLC, and that its inhibition exposes a context-dependent vulnerability that can be leveraged to enhance chemotherapy efficacy.