Biology subjects

Gong, L.

Publications and source records attributed to Gong, L..

At least 19 recordsLinked to original sources

bioRxiv2026

Dissecting the TMEM132A-EGFR Dependency to Unlock Translational Therapeutic Opportunities for Pan-Solid Tumor

Solid tumors remain refractory to conventional treatments, yet cell surface proteins, by virtue of their extracellular accessibility and critical roles in tumor signaling, represent an attractive class of targets for precision-targeted therapy. Here, we report that TMEM132A is an essential and previously unrecognized pan-cancer target. TMEM132A interacts directly with EGFR and stabilizes its expression, thereby tethering EGFR at the plasma membrane and sustaining constitutive activation of lipid synthesis. Mechanistically, the TMEM132A-EGFR axis promotes lipogenesis by facilitating SREBP nuclear translocation, which in turn upregulates ACLY and ACSS2 expression to drive acetyl-CoA production and downstream lipid biosynthesis, ultimately disrupting lipid droplet homeostasis. To therapeutically target this axis, we developed a nanobody, LFNanoT132A#3, which effectively blocks the TMEM132A-EGFR interaction, abrogates downstream signaling activation, and potently inhibits proliferation across multiple solid tumor types. Notably, LFNanoT132A also exerts robust antitumor activity against H1975 xenografts, a model resistant to first- and second- generation EGFR inhibitors, underscoring its potential to overcome conventional drug resistance. Our findings establish TMEM132A#3 as a critical node in membrane-tethered oncogenic signaling and metabolic rewiring, and position LFNanoT132A#3 as a promising therapeutic candidate for precision cancer therapy.

cancer biology↗

bioRxiv2026

A gene-augmentation platform for early-stage autosomal recessive retinitis pigmentosa

Most recessive inherited retinal dystrophies are, in principle, amenable to gene augmentation, yet only one such therapy has received regulatory approval. We sought to identify tractable autosomal recessive retinitis pigmentosa (RP) genes that could be treated using existing non-proprietary adeno-associated virus (AAV) components. More than 100 RP-associated genes were prioritized according to cellular expression, coding-sequence size, and the availability of cell type-specific promoters, yielding 19 candidate genes expressed predominantly in rods and/or retinal pigment epithelium (RPE). In rhesus monkey eyes, the human RHO and BEST1 promoters drove rod- and RPE-specific expression, respectively, whereas the GFAP and RLBP1 promoters were limited by absent Muller glial expression or dose-associated RPE toxicity. We selected PDE6B as a proof-of-concept gene and evaluated AAV8-RHO-PDE6B after neonatal subretinal delivery. The vector effectively preserved outer nuclear layer structure, electroretinography responses, and visually guided behaviors in rd1 and rd10 mice for at least 6 months. Dose-ranging studies identified retinal abnormalities at the higher doses, whereas the lower doses were comparatively well tolerated in eyes of mice and rhesus monkeys. Together, these findings define a preclinical framework for developing gene-augmentation vectors for a subset of early-stage autosomal recessive RP patients.

genetics↗

bioRxiv2026

STING agonist-mediated endothelial cell activation drives NK cells and neutrophils-dependent pulmonary inflammation

Stimulator of interferon genes (STING) agonists and derivative molecules have been extensively developed for tumor immunotherapy. However, systemic exposure toxicity risks have constrained clinical trial progression and even threatened patient lives. Currently, systematic toxicity assessments for STING agonists remain lacking, with the mode of action for major organ injury yet to be elucidated. Here, we focused on STING agonist-induced lung injury, revealing that systemic administration of STING agonists caused pulmonary hemorrhage, inflammatory alterations, and respiratory dysfunction. Through single-cell RNA sequencing and immune deletion studies, we found that lung endothelial cells could be stimulated by STING agonists and then secreted chemokines and IL-15 to recruit and activate NK cells. NK cells could induce endothelial cell apoptosis via IFN-{gamma}. Tbx21+ NK subpopulations, which activated by endothelial cells, could produce chemokines to recruit neutrophils. Neutrophils secreted IL-1{beta} through positive feedback pathways and form neutrophil extracellular traps during lung injury. This study elucidates the critical role of the endothelial cell-NK cell-neutrophil axis in mediating STING agonist-associated pneumonia, offering insights for developing intervention strategies for STING agonist toxicity.

pharmacology and toxicology↗

bioRxiv2026

CTLA-4 inhibitors drive colitis through metabolic reprogramming-mediated Treg/Th17 imbalance

Immune checkpoint inhibitors (ICIs), especially CTLA-4 inhibitors (CTLA-4), exhibit a high incidence of colitis as an immune-related adverse event (irAE) during cancer treatment, severely limiting patient benefit. Clinically, both treatment interruption and existing intervention drugs for ICI-mediated colitis may compromise antitumor efficacy. However, there is inadequate research on the pathogenesis of ICI-mediated colitis, with findings often conflicting. Here, we first established multiple clinically relevant animal models, including an immuno-humanized ICI-mediated colitis model. Through time-series transcriptomics, we discovered that CTLA-4-induced colonic toxicity exhibits characteristics ranging from early metabolic reprogramming represented by glycolysis to later immune disorders represented by Th17 responses. By targeting colonic CTLA-4+ T cells, CTLA-4 blocked CD80/CD86-CTLA-4 interaction, thereby activating the PI3K-AKT-mTOR pathway. Subsequently, mTOR mediated metabolic reprogramming in T cells, shifting them from Treg-biased oxidative phosphorylation to Th17-biased glycolysis. The colonic toxicity of CTLA-4 has also been demonstrated to depend on the PI3K-AKT-mTOR pathway, glycolysis, and Th17 responses. Notably, metformin significantly relieved ICI-mediated colitis by inhibiting mTOR without impeding antitumor efficacy. Collectively, these findings highlighted the metabolic-immune axis in the colonic toxicity of ICI and provided a clinically superior intervention strategy.

pharmacology and toxicology↗

bioRxiv2026

Multitimescale Computation by Astrocytes

The basic computational unit of the brain has long been defined as the neuron. However, mounting evidence suggests that other cells, especially astrocytes, also perform computations. Here, we demonstrate that cerebellar astrocytes decompose norepinephrine input into slow and fast calcium ion activities through differential adrenergic receptor engagement. During reward learning in mice, these slow and fast activities selectively target and modulate distinct synaptic pathways. Causal manipulations reveal that fast 2-adrenergic signals govern event-triggered responses and reinforcement learning, whereas slow 1-adrenergic signals maintain behavioral states and coordinate transitions. Remarkably, an actor-critic neural network trained on a similar sequence task spontaneously recapitulates these multitemporal dynamics, suggesting that astrocytes implement critic-like computations that evaluate states and modulate neuronal learning. These findings establish astrocytes as multilevel processors that transform univariate neuromodulatory inputs into multivariate, pathway-specific circuit controls operating in parallel with neuronal processing.

neuroscience↗

bioRxiv2025

Organoid Pharmacotyping of Pancreatic Cancer Enables Functional Precision Oncology and Drug Repurposing

PurposePancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest malignancies, with limited benefit from current cytotoxic regimens and poor predictive value of genomics alone. Patient-derived organoids (PDOs) represent a promising platform for functional precision oncology, yet systematic pharmacotyping of genomically annotated PDAC PDOs remains sparse. Experimental DesignWe established a clinically annotated panel of ten treatment-naive PDAC PDOs spanning well-, moderately-, and poorly differentiated tumors. PDOs were evaluated for morphologic and genomic fidelity and screened against 1,813 clinically relevant small molecules in a high-throughput 384-well format. Drug sensitivities were quantified at the compound and drug-family levels and integrated with histologic grade, pathway-level mutational profiles, and available clinical treatment information. ResultsPDOs preserved hallmark tumor features, including glandular organization and subclonal mutational architecture. Pharmacotyping revealed both shared and subtype-specific vulnerabilities. Classical (well/moderately differentiated) PDOs showed enriched mutations in DNA repair, mitotic spindle, and chromatin-regulatory pathways and were preferentially sensitive to topoisomerase inhibitors, microtubule poisons, and HDAC inhibitors. In contrast, basal (poorly differentiated) PDOs displayed coordinated defects in mitochondrial function, vesicle trafficking, and ubiquitin-mediated proteostasis, at the pathway level, that conferred a previously unrecognized vulnerability to cardiac glycosides. Sensitivities to standard PDAC agents were heterogeneous across models, underscoring the limited predictive value of genotype alone and the need for functional drug testing. ConclusionsThis integrated genomic and pharmacologic analysis demonstrates that PDO pharmacotyping identifies biologically grounded, actionable vulnerabilities in PDAC, including novel therapeutic opportunities in basal, chemo-resistant tumors. These findings support PDO-guided functional profiling as a clinically relevant platform for refining drug selection and expanding treatment options for patients with PDAC. SignificancePDAC is dominated by chemoresistance and lacks reliable genomic predictors of therapy response. By integrating high-throughput drug screening with mutation-informed pathway analysis in patient-derived organoids, we identify differentiation-linked therapeutic liabilities, including a previously unrecognized vulnerability to cardiac glycosides in basal PDAC. These results highlight PDO pharmacotyping as a powerful functional complement to genomics for guiding treatment selection in pancreatic cancer.

cancer biology↗

bioRxiv2025

Web engine for tumor pathology image retrievals on massive scales

Hematoxylin and Eosin staining (H&E) is widely used in clinical practice, but efficient and versatile image retrieval tools are lacking. We developed the H&E Retrieval Engine (HERE, https://hereapp.ccr.cancer.gov) to analyze patient cases based on image similarities to database records. Using H&E image regions as input, HERE searches 21.2 terabytes of whole-slide images from multiple tumor histopathology cohorts through a 12.1-gigabyte memory index, and returns top images containing regions similar to the query. HERE scans high-resolution images in the database using accurate artificial intelligence encoding and ultra-efficient hierarchical skip indexing. HERE demonstrated performance superior to existing image retrieval tools based on blinded pathologist scoring using benchmark queries that represent key image features of human tumors. By pairing spatial transcriptomics with H&E images, HERE also enables retrieving image features from gene transcriptomics input and identifies molecular pathways associated with tumor histologies.

bioinformatics↗

bioRxiv2025

Post-inhibitory rebound firing drives hypothalamic activation for male mating

Many behaviorally relevant limbic circuits are dominated by inhibitory connections, raising the question of how neuronal activation arises in such contexts. In male mating, both activation of mPOA and its inhibitory inputs are essential--a paradox previously ascribed to disinhibition. Here, we show that the mPOA largely lacks local inhibitory circuits, arguing against disinhibition. Instead, in vivo recordings reveal that mount-active mPOA neurons are suppressed prior to behavioral onset, and this inhibition negatively correlates with subsequent activation, consistent with post- inhibitory rebound firing (PIR). A biologically plausible conductance-based model demonstrates that synaptic inhibition interacts with T-type Ca{superscript 2} currents -- the ionic basis of PIR -- to promote mPOA neuron firing. Experimentally, bidirectional manipulations of mPOA T-type Ca{superscript 2} channels confirm this mechanism: knockdown reduces PIR and impairs male mating, while overexpression enhances mating. Together, these results identify PIR as a critical mechanism by which inhibition promotes activation in limbic circuits to drive male mating.

neuroscience↗

bioRxiv2025

BioMedTools: a language model-powered community for biomedical computational tools

A large number of biomedical computational tools have spawned several tool registries. However, in the face of the rapid growth in the number of tools, existing tool registries, which are manually curated or community-driven, are difficult to keep up to date, resulting in inadequate tool repository data. In this paper, we show that language models (LMs) can aid in building a community of tools. We introduce BioMedTools (https://biomed.tools), a community of biomedical computational tools that mainly implements LM-based tool identification and a chat assistant. Compared with existing tool registries, BioMedTools achieves excellence in terms of the number of tools, frequency of data updates, and functionality. Meanwhile, the Model Context Protocol (MCP) servers hub in BioMedTools may promote the building of agents in the biomedical field. BioMedTools enables the efficient collection of tools and enhances their findability and accessibility.

bioinformatics↗

bioRxiv2025

Single-Cell eQTL Mapping Reveals Cell Type-Specific Genetic Regulation in Lung Cancer

Genome-wide association studies (GWAS) have identified over 50 lung cancer risk loci; however, the precise cellular context of these genetic mechanisms remains unclear due to limitations in bulk tissue eQTL analyses. Here, we present the largest single-cell eQTL atlas of human lung tissue to date, profiling 222 donors using multiplexed scRNA-seq. We identified 16,785 eQTLs across 17 cell types, with over 90% of sc-eQTLs and 59% eGene being cell-type-specific, and fewer than 23% were detectable in paired bulk datasets. Integration with GWAS for non-small cell lung cancer highlighted epithelial and immune cells as key contributors to genetic susceptibility, identifying 28 candidate genes within known risk loci and 24 in novel regions. Notably, 47% of established NSCLC susceptibility loci exhibited cell-type-specific pleiotropic genetic regulation. This study provides a valuable resource of lung sc-eQTLs and illuminates how genetic variation modulates gene expression in a cell-type-specific fashion, contributing to lung cancer susceptibility.

genetics↗

bioRxiv2025

Hepatic Arterial Flow-Induced Portal Tract Fibrosis in Portal Hypertension: The Role of VCAM-1 and Osteopontin-Expressing Macrophages

BackgroundThe liver undergoes significant hemodynamic changes during surgery, transplantation, or cirrhosis with portal hypertension(PH). The hepatic artery buffer response(HABR), which compensates for reduced portal venous flow by increasing hepatic artery(HA) flow, is hypothesized to induce pathological portal tract remodeling. This study investigates the molecular mechanisms underlying this process. MethodsPH was induced in Sprague-Dawley rats via partial portal vein ligation(PPVL). Structural evaluation(microCT), immune cell profiling, hemodynamic measurements, and transcriptomic analysis in macrophages(M{phi}) from sham or PPVL rats were conducted. ResultsMicroCT revealed decreased portal vein flow and increased HA flow correlated with portal pressure(r=0.799, p<0.01). A 2-fold increase in portal tract fibrosis(p<0.001) was observed with increased -SMA+ myofibroblasts in PPVL rats. CD68+ M{phi} peaked at 10 days post-PPVL, and their depletion significantly reduced fibrosis(p<0.001), indicating critical roles of M{phi} in portal tract remodeling. VCAM-1 was elevated in HA endothelium and portal fibroblasts (PFs); VCAM-1 neutralization reduced collagen accumulation(p<0.05), CD68+ M{phi}(46.3%, p<0.01), and CD3+ T cells(18%, p<0.05). M{phi}-conditioned medium increased VCAM-1 in PFs(8-fold, p<0.001) and enhanced PF migration, while VCAM-1 knockdown reduced this effect (p<0.01). Single-cell RNA sequencing data(GSE171904) and RNA-FISH revealed increased interactions between osteopontin (Spp1)+ M{phi} and PFs, with Spp1+ M{phi} driving fibrosis. Spp1 knockdown in M{phi} co-culture reduced PF fibrogenic markers, while recombinant Spp1 upregulated Col1a1, Fn1, and Acta2 expression in PFs. ConclusionIncreased VCAM-1 in arterial endothelial cells and PFs facilitates the recruitment of Spp1+ M{phi}, which drive HA flow-mediated vascular remodeling and portal tract fibrosis. These findings highlight arterial flow-induced fibrosis as a key mechanism in PH, potentially contributing to disease progression and decompensation. SynopsisLiver hemodynamic changes in portal hypertension drive extracellular matrix accumulation and portal tract remodeling via Spp1+ macrophages. This study highlights how altered blood flow induces fibrosis, and its potential role in decompensation, and identifies therapeutic targets for advanced liver disease.

pathology↗

bioRxiv2024

UBR-1 deficiency leads to ivermectin resistance in C. elegans

Resistance to anthelmintics, particularly the macrocyclic lactone ivermectin (IVM), presents a substantial global challenge for parasite control. We found that the functional loss of an evolutionarily conserved E3 ubiquitin ligase, UBR-1, leads to IVM resistance in Caenorhabditis elegans. Multiple IVM-inhibiting activities, including viability, body size, pharyngeal pumping, and locomotion, were significantly ameliorated in various ubr-1 mutants. Interestingly, exogenous application of glutamate induces IVM resistance in wild-type animals. The sensitivity of all IVM-affected phenotypes of ubr-1 is restored by eliminating proteins associated with glutamate metabolism or signaling: GOT-1, a transaminase that converts aspartate to glutamate, and EAT-4, a vesicular glutamate transporter. We demonstrated that IVM-targeted GluCls (glutamate-gated chloride channels) are downregulated and that the IVM-mediated inhibition of serotonin-activated pharynx Ca2+ activity is diminished in ubr-1. Additionally, enhancing glutamate uptake in ubr-1 mutants through ceftriaxone completely restored their IVM sensitivity. Therefore, UBR-1 deficiency-mediated aberrant glutamate signaling leads to ivermectin resistance in C. elegans.

genetics↗

bioRxiv2024

EPOP Restricts PRC2.1 Targeting to Chromatin by Directly Modulating Enzyme Complex Dimerization

Polycomb repressive complex 2 (PRC2) mediates developmental gene repression as two classes of holocomplexes, PRC2.1 and PRC2.2. EPOP is an accessory subunit specific to PRC2.1, which also contains PCL proteins. Unlike other accessory subunits that collectively facilitate PRC2 targeting, EPOP was implicated in an enigmatic inhibitory role, together with its interactor Elongin BC. We report an unusual molecular mechanism whereby EPOP regulates PRC2.1 by directly modulating its oligomerization state. EPOP disrupts the PRC2.1 dimer and weakens its chromatin association, likely by disabling the avidity effect conferred by the dimeric complex. Congruently, an EPOP mutant specifically defective in PRC2 binding enhances genome-wide enrichments of MTF2 and H3K27me3 in mouse epiblast-like cells. Elongin BC is largely dispensable for the EPOP-mediated inhibition of PRC2.1. EPOP defines a distinct subclass of PRC2.1, which uniquely maintains an epigenetic program by preventing the over-repression of key gene regulators along the continuum of early differentiation.

molecular biology↗

bioRxiv2024

Identification of targetable vulnerabilities of PLK1-overexpressing cancers by synthetic dosage lethality

Tumor heterogeneity poses a significant challenge in combating treatment resistance. Despite Polo-like kinase 1 (PLK1) being universally overexpressed in cancers and contributing to chromosomal instability (CIN), direct PLK1 inhibition hasnt yielded clinical progress. To address this, we utilized the synthetic dosage lethality (SDL) approach, targeting PLK1s genetic interactions for selective killing of overexpressed tumor cells while mitigating heterogeneity-associated challenges. Employing computational methods, we conducted a genome-wide shRNA screen, identifying 105 SDL candidates. Further in vivo CRISPR screening in a breast cancer xenograft model and in vitro CRISPR analysis validated these candidates. Employing Perturb-seq revealed IGF2BP2/IMP2 as a key SDL hit eliminating PLK1-overexpressing cells. Suppression of IGF2BP2, genetically or pharmacologically, downregulated PLK1 and limited tumor growth. Our findings strongly propose targeting PLK1s genetic interactions as a promising therapeutic approach, holding broad implications across multiple cancers where PLK1 is overexpressed.

cancer biology↗

bioRxiv2024

A nanobody-enzyme fusion protein targeting PD-L1 and sialic acid exerts anti-tumor effects by affecting tumor associated macrophages

Cancer cells employ various mechanisms to evade immune surveillance. Their surface features, including a protective "sugar coat" and immune checkpoints like PD-L1 (programmed death ligand 1), can impede immune cell recognition. Sialic acids, which carry negative charges, may hinder cell contact through electrostatic repulsion, while PD-L1 transmits immunosuppressive signals to T cells. Furthermore, cancer cells manipulate macrophages within the tumor microenvironment to facilitate immune escape. Prior research has demonstrated the effectiveness of separately blocking the PD-L1 and sialic acid pathways in eliciting anti-tumor effects. In this study, we investigated the relationship between PD-L1 expression and genes associated with sialic acid in clinical databases. Subsequently, we developed a novel nanobody enzyme fusion protein termed Nb16-Sia to simultaneously target both PD-L1 and sialic acid pathways. In vivo experiments confirmed the anti-tumor activity of Nb16-Sia and highlighted its dependence on macrophages. Further investigations revealed that Nb16-Sia could polarize macrophages towards the M1 phenotype through the C-type lectin pathway in vitro and eliminate tumor-associated macrophages in vivo. In conclusion, our findings demonstrate that the fusion of PD-L1 nanobody with sialidase effectively targets tumor-associated macrophages, resulting in significant anti-tumor effects. This approach holds promise for drug development aimed at enhancing immune responses against cancer.

pharmacology and toxicology↗

bioRxiv2024

Pioneer factor ETV2 safeguards endothelial cell specification by recruiting the repressor REST to restrict alternative lineage commitment

Mechanisms of cell fate specification remain a central question for developmental biology and regenerative medicine. The pioneer factor ETV2 is a master regulator for the endothelial cell (EC) lineage specification. Here, we studied mechanisms of ETV2-driven fate specification using a highly efficient system in which ETV2 directs human induced pluripotent stem cell-derived mesodermal progenitors to form ECs over two days. By applying CUT&RUN, single-cell RNA-sequencing (scRNA-seq) and single-cell assay for transposase-accessible chromatin sequencing (scATAC-seq) analyses, we characterized the transcriptomic profiles, chromatin landscapes, dynamic cis-regulatory elements (CREs), and molecular features of EC cell differentiation mediated by ETV2. This defined the scope of ETV2 pioneering activity and identified its direct downstream target genes. Induced ETV2 expression both directed specification of endothelial progenitors and suppressed acquisition of alternative fates. Functional screening and candidate validation revealed cofactors essential for efficient EC specification, including the transcriptional activator GABPA. Surprisingly, the transcriptional repressor REST was also necessary for efficient EC specification. ETV2 recruited REST to occupy and repress non-EC lineage genes. Collectively, our study provides an unparalleled molecular analysis of EC specification at single-cell resolution and identifies the important role of pioneer factors to recruit repressors that suppress commitment to alternative lineages.

cell biology↗

bioRxiv2024

The Transcription Factor OsNAC5 Mediates Cadmium Stress Response and Accumulation in Rice

Cadmium (Cd) is a toxic heavy metal that endangers human health through contaminated rice consumption. Reducing Cd uptake in rice is essential for minimizing grain Cd accumulation. However, the transcriptional regulation of Cd uptake in rice remains largely elusive. This study reveals that the transcription factor OsNAC5 in Oryza sativa positively regulates the Cd transporter gene OsNRAMP1, influencing Cd uptake. OsNAC5 is primarily expressed in roots, localized to the nucleus, and upregulated by Cd-induced H2O2. Knocking out OsNAC5 reduces Cd levels in both shoots and roots and increases Cd sensitivity. OsNRAMP1 expression, enhanced by Cd stress, depends on OsNAC5, which binds to "CATGTG" motifs in the OsNRAMP1 promoter activating its expression. Loss of OsNAC5 function decreases Cd accumulation in rice grains. Our findings elucidate the transcriptional regulation of Cd stress response in rice and suggest biotechnological approaches to reduce Cd uptake in crops. Declaration of Competing InterestThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

plant biology↗

bioRxiv2024

CMTM6 maintains B cell intrinsic CD40 expression to regulate anti-tumor immunity

HighlightsO_LIB cells participate in anti-tumor immunity by influencing the intratumoral infiltration and function of T cells; C_LIO_LICMTM6 cis-interacts with CD40 and inhibits ubiquitin/proteasome-mediated CD40 degradation to maintain CD40 cell membrane levels; C_LIO_LILoss of B cell-intrinsic CMTM6 significantly reduces CD40 signaling-mediated B cell activation, survival, differentiation, T/B cell interaction and anti-tumor immunity; C_LIO_LIB cell-intrinsic CMTM6 deficiency leads to a significant reduction in the anti-tumor activity CD40 agonists and ICB therapy. C_LI In BriefLong et al. demonstrate that B-cell intrinsic CMTM6 regulates CD40 signaling and function via maintaining the cell membrane level of B-cell CD40 through ubiquitin-proteasome pathway inhibition, thereby affecting B cell function, anti-tumor B-cell immunity and the efficacy of CD40 agonist and ICB therapy. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=137 SRC="FIGDIR/small/583639v2_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@7639cdorg.highwire.dtl.DTLVardef@1ccddaaorg.highwire.dtl.DTLVardef@ecc9f3org.highwire.dtl.DTLVardef@1be8cb0_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphic AbstractsC_FLOATNO C_FIG The essential role of B cells and B cell intrinsic molecules in tumor immunity is beginning to be recognized. Tumor cell CMTM6 is a novel tumor immunoregulator involved in maintaining membrane levels of several important molecules, such as PD-L1 and CD58. Host CMTM6 may also play a function in the tumor microenvironment. Here, we found that CMTM6 was highly expressed in splenic B cells and tumor-infiltrating B cells. CMTM6 deficiency resulted in impaired splenic development, germinal center B cell differentiation, memory B cell differentiation, T/B cell interaction and B cell anti-tumor immune responses. Through multi-omics data mining and B-cell agonist screening, we identified that CMTM6 interacted with CD40 and maintained CD40 membrane levels in B cells. CMTM6 cis-interacts with CD40 and inhibits ubiquitin/proteasome-mediated CD40 degradation. CMTM6 deficiency led to impaired CD40 signaling-mediated B cell activation, survival, proliferation, differentiation and T/B cell interaction. In vivo, CMTM6 deficiency leads to a significant decrease in the anti-tumor activity of ICB therapy and B cell-dependent CD40 agonists. Collectively, B-cell intrinsic CMTM6 maintains B cell CD40 levels and signaling to promote B cell function and anti-tumor immunity.

immunology↗