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Liu, Y.

Publications and source records attributed to Liu, Y..

At least 811 records · Page 45Linked to original sources

Cross-modal Denoising and Integration of Spatial Multi-omics data with CANDIES

Spatial multi-omics data offer a powerful framework for integrating diverse molecular profiles while maintaining the spatial organization of cells. However, inherent variations in data quality and noise levels across different modalities pose significant challenges to accurate integration and analyses. In this paper, we introduce CANDIES, which leverages a conditional diffusion model and contrastive learning to effectively denoise and integrates spatial multi-omics data. With our innovative model and algorithm designs, CANDIES not only enhances the quality of spatial multi-omics data, but also yields a unified and comprehensive joint representation, thereby empowering many downstream analysis. We conduct extensive evaluations on diverse synthetic and real datasets, including spatial CITE-seq data from human skin biopsy tissue, MISAR-seq data from the mouse brain, spatial ATAC-RNA-seq data from the mouse embryo and 10x visium data from human lymph nodes. CANDIES shows superior performance on various downstream tasks, including denoising, spatial domain identification, spatiotemporal trajectories reconstruction, and spatial association mapping for complex human traits. In particular, we show that CANDIES representations can be integrated with the rich resources from genome-wide association studies (GWASs), allowing the spatial domains to be linked with complex human traits, yielding spatially resolved interpretation of complex traits in their relevant tissues.

bioinformatics↗

HIF-1α/STOML2 mediated PINK1-dependent mitophagy activation against hypoxia-induced neuronal injury

Hypoxia contributes to brain disorders by causing neuronal injury. However, in the early stage of stress, neurons initiate a series of compensatory pathways to resist cell damage, but the underlying mechanisms have not been fully elucidated. In this study, we found that hypoxia transiently activates PTEN-induced kinase 1 (PINK1)-dependent mitophagy in the early stage before cell damage and neurological dysfunction. PINK1 overexpression protects neurons and it knockdown exacerbates neuronal damage, highlighting the key role of PINK1-dependent mitophagy in hypoxic adaptation. Mechanistically, hypoxia promotes HIF-1 nuclear translocation, inducing transcription of stomatin like 2 (STOML2). STOML2 relocates to the mitochondrial membrane, aiding phosphoglycerate mutase 5 (PGAM5) cleavage, which triggers PINK1-dependent mitophagy. Silencing HIF-1, STOML2, or PGAM5 inhibits PINK1-dependent mitophagy and worsens neurological function under hypoxia. Notably, intermittent hypoxia, a hypoxic conditioning strategy for improving hypoxic tolerance, enhances PINK1-dependent mitophagy by activating HIF-1/STOML2 axis, and protects neurons against hypoxia. In conclusion, our study reveals a new "self-protection" mechanism of neurons against hypoxic stress and discovers that intermittent hypoxia is a potential therapeutic strategy against hypoxia-induced injury.

neuroscience↗

Breaking the Link: Neural Dissociation of Attention and Working Memory through Inhibitory Control

Attention and working memory (WM) encoding have traditionally been considered inseparable processes with shared neural mechanisms. Here, using an innovative experimental design and a multimodal approach, we provide the first direct neural evidence that attention and WM encoding are dissociable. Functional MRI identifies the supramarginal gyrus (SMG) as the key region enabling this dissociation, while dynamic causal modeling reveals the neural circuitry through which the SMG exerts inhibitory control over attentional representations, regulating their integration into WM. Furthermore, neuromodulation via transcranial direct current stimulation (tDCS) demonstrates that enhancing SMG activity strengthens this inhibitory control, providing causal evidence for the dissociation mechanism. A second tDCS experiment with varied stimuli confirms the generalizability of this mechanism and reinforces the robustness of our results. These findings challenge the long-standing view that attention and WM encoding form a continuous process, demonstrating instead that they constitute two dissociable neural processes of information selection.

neuroscience↗

RIP2 inhibits DOCK8-mediated platelet dense granule release and alleviates experimental myocardial infarction

ObjectiveReceptor-interacting protein 2 (RIP2) is an essential mediator of inflammation and innate immunity downstream of pattern recognition receptors (PRRs). Platelets express RIP2, while its role in platelet activation, thrombosis, and myocardial infarction (MI) is unknown. Approach and ResultsHere we show that RIP2 deficiency enhances platelet dense granule secretion in response to GPIb and GPVI activation; platelet aggregation in whole blood and adhesion under arterial shear are also increased. Consistently, RIP2 inhibitor WEHI-345 potentiates human platelet dense granule secretion and inhibits RIP2 phosphorylation induced by thrombin and collagen. These phenotypes are translated into shorter bleeding time, accelerated FeCl3-induced arterial thrombosis. Importantly, platelets from patients with coronary artery disease and mice with atherosclerosis express lower RIP2, and RIP2 deficiency deteriorates MI and cardiac function in a mouse ischemia/reperfusion model. Mechanistically, we found that platelets express dedicator of cytogenesis protein 8 (DOCK8), which is sequestered by phosphorylated RIP2 (p-RIP2), causing inhibition of Cdc42 activation and subsequent dense granule release. ConclusionsIn conclusion, RIP2 inhibits platelet activation, thrombosis, and ameliorates MI. Our results also suggest that a novel PRR-independent pathway, p-RIP2-DOCK8-Cdc42, negatively regulates platelet activation downstream of GPIb and GPVI. Platelet RIP2 pathway may be promising for therapeutic intervention of atherothrombotic diseases from early atherosclerosis stage to arterial thrombosis and MI. HighlightsO_LIRIP2 inhibits platelet dense granule release NOD2-independenly via pRIP2-DOCK8-Cdc42. C_LIO_LIThe negative regulation of RIP2 on platelet activation is translated into enhanced thrombosis, exacerbated myocardial infarction (MI). C_LIO_LIRIP2 pathway booster may be an approach for therapeutic intervention of atherothrombotic diseases. C_LI

molecular biology↗

Single and Multiple Buds Form characteristics in Amorphophallus muelleri

This study compared the physiological characteristics and transcriptomic profiles of single-budded and multi-budded corms, as well as developmental stages of foliar bulbils in Amorphophallus muelleri, to reveal regulatory mechanisms underlying bud development. Hormonal analysis showed that the IAA/CTK ratio was significantly higher in single-budded corms (1.9060 vs 1.5753), while multi-budded corms exhibited higher CTK (0.2766 g/g), BR (0.8692 p mol/g), and SLs (0.5090 ng/g) levels. During foliar bulbils development, ABA content peaked at 41.54 ng/g in the G2 stage, and sucrose reached maximum levels (6.86 mg/g) in the G1 stage. Transcriptomic sequencing identified 742 differentially expressed transcription factors, with over 80% of CRE1 and AHP genes in CTK signaling pathways significantly upregulated. KEGG pathway analysis highlighted starch/sucrose metabolism (215 DEGs) and plant hormone signal transduction (243 DEGs) as key regulatory networks. The study demonstrated that CTK signaling activation and carbohydrate metabolic reprogramming promoted multi-bud formation, while foliar bulbils development displayed stage-specific gene expression patterns, providing theoretical insights for improving konjac propagation coefficient.

physiology↗

Targeting protein glycosylation and cholesterol metabolism in chemoresistant pancreatic cancer

Chemotherapy remains the cornerstone of pancreatic ductal adenocarcinoma (PDAC) treatment. However, most cases of PDAC finally progress to advanced chemoresistant disease. This highlights an urgent need to develop new pharmacological strategies to overcome chemotherapy resistance using clinical grade inhibitors. Here, we established a biobank comprising 260 organoid lines derived from 322 pancreatic cancer patients. These organoids underwent extensive multi-omics profiling and drug sensitivity testing for both chemotherapy and targeted therapy. Increased protein glycosylation and cholesterol metabolism signaling pathways were especially enriched in chemoresistant organoid lines. Importantly, chemoresistant PDAC organoids were effectively targeted with statins, inhibitors of cholesterol synthesis. Statins treatment attenuated protein glycosylation, cholesterol levels, and the epithelial-to-mesenchymal transition (EMT) signature in PDAC organoids. We further conducted a phase 2 clinical trial (NCT06241352) combining atorvastatin with chemotherapy in patients with advanced chemoresistant pancreatic cancer. Among 29 patients, 21 (72.4%) demonstrated a response, with tumor markers decreasing by more than 20%, suggesting durable responses and potential clinical benefits in this challenging patient population. ClinicalTrials.gov identifier: NCT06241352.

cancer biology↗

DNA Methylation in Sex Chromosomes and Genes under Selection Underpins the Emergence of Sexual Size Dimorphism

Sexual size dimorphism (SSD) refers to the differences in body size between males and females. Epigenetics such as methylation contribute to shaping phenotypes, nevertheless, their role in SSD is still unclear. Here, we used Cynoglossus semilaevis, a species with larger females known as female-biased SSD, as a model to investigate the role of methylation in the emergence and regulation of SSD. Methylomes and transcriptomes were constructed in four tissues (brain, liver, muscle, and gonad) from three key life stages: juveniles (3-months post fertilization), male mature stage (1-year post fertilization; ypf), and female mature stage (3 ypf). In 1 ypf and 3 ypf females showed lower methylation, while the number of differentially methylated regions between sexes increased during the lifetime. Genes at the top of the growth hormone/insulin-like growth factor (GH/IGF) axis and hypothalamus-pituitary-gonadal axis (gh1, igf1, gnrhr2r-like, err{gamma}, etc.) showed differential methylation between sexes, consistent with sex-related differences in growth. The female-specific W chromosome showed higher methylation than the autosomes or the Z chromosome. Genes of the IGF signaling network that negatively regulate growth and located on W chromosome were hyper-methylated than their Z homologs. Furthermore, genes with a faster evolutionary rate in C. semilaevis exhibited lower methylation levels than the background genes, suggesting an important evolutionary role for DNA methylation in shaping SSD. Our results provide a comprehensive depiction of methylation regulation of SSD in vertebrates, and improve our understanding of how methylation regulation can help organisms to respond to natural selection, and allocate resources between the sexes.

developmental biology↗

Molecular insights into early malignant transition of hepatocellular carcinoma

The molecular continuum of premalignant-to-malignant transition remains elusive in carcinogenesis, primarily due to the difficulty in sampling transitional lesions. Here, we present comprehensive genomic and immunological profiling of 21 very early hepatocellular carcinomas (veHCCs) arising within 17 cancer-prone DNs. Surprisingly, 82% of cancer-prone DNs harbored TERT alterations, suggesting a predisposing rather than causative role in malignancy transition. A substantial increase in CNA burden, rather than SNV, was noted, indicating a role of chromosome instability in malignancy transition. Additionally, veHCC-originating DNs showed immune inactivity, not falling into the prevailing paradigm that HCCs develop in a context of chronic inflammation. 43% of veHCCs showed an inflamed phenotype with relatively mild CNA burden but already exhibited immune evasion features. Two major evolutionary scenarios were thus proposed: 1) CNA-dominant progression and 2) early immune evasion of those with mild CNA burden. Collectively, our findings illustrate previously unexplored molecular paradigms in HCC initiation, highlighting the therapeutic potential of immunotherapy for early intervention.

cancer biology↗

Exploring Population Differences in the Human Gut Microbiome: from Microbial Abundance to Single Nucleotide Polymorphisms

The human gut microbiota exhibits significant diversity across populations, influenced by factors such as geography, diet, and lifestyle, particularly between the Han Chinese and non-Chinese populations. While previous studies have predominantly focused on the taxonomic abundance of the gut microbiome, the impact of single nucleotide polymorphisms (SNPs) in driving population-specific differences remains largely underexplored. In this study, we systematically investigated gut microbial differences between the Han Chinese and non-Chinese populations using the Human Gut Microbiome Reference Genome Catalog (HGMRGC). HGMRGC includes 271,480 non-redundant genomes from 5,785 prokaryotic species, which was generated by metagenomic sequencing data from 9,320 publicly available samples across 22 countries and 3,584 newly sequenced samples from Han Chinese individuals across 29 provinces and regions in China. We observed geography was the primary driver of microbial variation of abundance and SNPs. We identified 625 novel population-specific genome clusters from HGMRGC with functional differences in carbohydrate utilization and 126 species exhibiting distinct prevalence related to vitamin biosynthesis, antibiotic resistance, and carbohydrate metabolism. Beta diversity analysis highlighted significant inter-population differences in both microbial abundance and SNPs, while alpha diversity analysis revealed that non-Chinese populations exhibited higher diversity in microbial abundance, and Han Chinese populations displayed greater diversity in SNPs. These results provide valuable insights into population-specific microbial diversity, laying the groundwork for future research on its functional and health implications.

microbiology↗

A zebrafish immunodeficiency model induced by the combination of Tacrolimus and Everolimus for rapid assessment of immune-enhancing agents

A methodology for the assessment of the immune-enhancing effects of various substances within a period of 5 days was reported. Experimentally, it was determined that the continuous treatment of Tacrollimus (0.5 ng/mL) and Everolimus (5 g/mL) on zebrafish from 48 hpf to 120 hpf was sufficient to establish an immunodeficient model. The results showed that the model exhibited a significant reduction in the number of immune cells (thymocytes, myeloid cells, and macrophages) and a greater than 50% decrease in the expression of immune-related genes (itk, hexb, cpa5, isg15, rsad2). Astragalus powder can effectively increase the content of thymic T cells and macrophages, but its effect on myeloid cells is limited. Ganoderma lucidum spore powder had the most obvious influence on macrophages, with limited impact on thymus cells and myeloid cells. Royal jelly showed a significant effect on thymus T cells and macrophages, but its effect on myeloid cells was limited. Bailing capsule can significantly increase the content of myeloid cells and thymus T cells, while its effect on macrophages was limited. The study showed immune indexes varied in recovery with different immunomodulators versus the model group, suggesting they may act via distinct mechanisms. Summary StatementA robust immune system is vital to overall health and quality of life. Recent years have witnessed surging development of immune-boosting pharmaceuticals, nutraceuticals, and functional foods. However, an easy-to-use, rapid and intuitive immunity assessment framework is still missing. Here, a methodology for the assessment of the immune-enhancing effects of various substances within a period of 5 days was reported.

immunology↗

Cancer Cell Adaptation to Cycling Hypoxia: Integrating Mathematical Modeling with Experimental Validation of HIF-1 Dynamics

The adaptive response of cancer cells to hypoxia, a key microenvironmental factor in solid tumors, is intricately orchestrated by Hypoxia-inducible factor 1 (HIF1). Evidence is accumulating on oxygen dynamics in tumor cores, showing that hypoxia is frequently unstable, or cycling, associated with specific phenotypic outcomes for the cancer. Transcriptomic analysis show that most gene expression changes in cycling hypoxia lie in between the change caused by stable hypoxia, suggesting multi-cycle averaging of dosage in the oxygen tension, and likely HIF-1 induced transcription. However, small subset of genes show an oscillation/cycling hypoxia specific response, suggesting that the transcriptional machinery of these genes may interpret cycling HIF-1 activity differently from stably high HIF-1 activity. Here, we model a gene regulatory circuit, the incoherent feed-forward loops (IFFLs) to explore parameter regimes where oscillatory specific transcription is plausible. In these IFFL models, HIF-1 regulates gene transcription of a target gene directly, as well indirectly via another transcription factor with an opposite effect on gene transcription. We have identified several plausible parameter regimes where oscillation specific gene expression can occur, with potentially significant effect on cancer growth and progression. Finally, we experimentally confirmed that HIF-1 can form IFFLs with two key transcription factors p53, and Notch1, resulting in cycling hypoxia specific gene expression linked to breast cancer progression and poor prognosis. Our models mechanistically reveal how temporal fluctuations in the tumor microenvironment may directly inform downstream transcription, identify hitherto unknown HIF-1 driven mechanism of cancer progression contributing to emergent tumor heterogeneity.

bioinformatics↗

Cerebellum-Targeted Transcranial Focused Ultrasound Stimulation Modulates Hippocampus Neural Activities

Low-intensity transcranial focused ultrasound stimulation (tFUS) has recently emerged as a promising neuromodulation technique due to its non-invasive nature, ability to penetrate deeply, and high spatial resolution. On the other hand, the cerebellum has attracted new interest as a target for neuromodulation. In this study, we investigated how cerebellum-targeted tFUS could modulate hippocampal neural activity. We found that tFUS at pulse repetition frequency (PRF) as high as 10kHz can effectively activate the cerebellum in vivo. Furthermore, PRF at 10kHz, rather than 1kHz, favored remote inhibition of hippocampus neurons. We found that the neuromodulation at hippocampus was mainly mediated by cerebellum cortex than deep cerebellar nucleus. Furthermore, by cFos expression mapping and phase-amplitude coupling analysis, we showed that the hippocampal response at different PRFs resulted from altered neurodynamic interaction rather than overall activation of engaged brain regions. Our results reveal new potential for cerebellum as a neuromodulation target for hippocampus-related functions.

bioengineering↗

Uncovering the molecular basis of high morphinan product efficiency in opium poppy through Multi-omics integrated analysis with multi-capsules

Exploring the genetic landscape and corresponding regulatory mechanisms influencing morphine and related alkaloid production efficiency in the opium poppy (Papaver Somniferum L.) is important for sustainable medicinal production. However, information regarding the corresponding medicinal properties of poppy subspecies remains elusive, and the correlation between agronomic traits and morphine production remains unclear. Therefore, this study aims to investigate the distinction between two poppy subspecies: Shan Yang (SY) and Lan Tian (LT). Physiological data revealed that SY exhibited greater tolerance to environmental stress and a higher morphine content than LT, especially during the reproductive stage. To investigate genetic and molecular mechanisms underlying different tolerance traits and morphine synthesis efficiencies, a comprehensive comparison of genomic, transcriptomic, and metabolomic data was conducted, showing significantly higher single nucleotide polymorphism (SNP) frequency in SY (23.78%) compared to LT (23.69%). The proportions of SKIP (Skipped Exon) and MIR (Multi Intron Retention) were higher in SY than in LT. SY showed significantly higher gene expression related to benzylisoquinoline alkaloid synthesis, especially those involved in the steps from 1,2 dehydroreticulinium to morphine, narcotoline and noscapine, compared to LT. The upregulated expression of phenylpropanoid biosynthesis-related genes contributes to its more resistant agronomical traits. It plays a synergistic role in alkaloid production. The higher morphine content in SY resulted from an integrated effect controlled at different levels. Summarily, our findings offer new insights into the molecular mechanisms of morphine synthesis and present valuable gene resources for improving poppy cultivars with higher morphine content.

genomics↗

TUCL-Seq for miRNA single molecule sequencing

MicroRNAs (miRNAs) are pivotal regulatory molecules in gene expression, and their precise quantification is essential for elucidating their roles in diverse biological processes. This research paper introduces a pioneering workflow for the single molecule sequencing (SMS) of miRNA, integrating advanced miRNA sample preparation with SMS sequencing. Central to our approach is TUCL-Seq, which is an automated, on-chip miRNA library preparation method designed to streamline the sequencing process. This innovative approach incorporates the addition of sequencing adaptor to RNA samples in solution, and converts it to cDNA on a sequencing flow cell for sequencing. Coupled with single molecule sequencing instrument and base-call software, our workflow significantly reduces sample-to-result time, and decreases the need for manual interventions compared to traditional SMS and next-generation sequencing methods. We demonstrate the efficacy of TUCL-Seq by accurately quantifying synthetic miRNA samples with a 24-hour workflow, showcasing its potential for high-throughput miRNA profiling. Our findings highlight the promise of this integrated workflow for advancing miRNA research and applications in diagnostics and therapeutics.

biochemistry↗

A proteogenomic tool uncovers protein markers for human microglial states

Human microglial heterogeneity has been largely described using transcriptomic data. Here, we introduce a microglial proteomic data resource and a Cellular Indexing of Transcriptomes and Epitopes by Sequencing panel enhanced with antibodies targeting 17 microglial cell surface proteins (mCITE-Seq). We evaluated mCITE-Seq on HMC3 microglia-like cells, induced-pluripotent stem cell-derived microglia (iMG), and freshly isolated primary human microglia. We identified novel protein microglial markers such as CD51 and relate expression of 101 cell surface proteins to transcriptional programs. This results in the identification and validation of three protein marker combinations with which to purify microglia enriched with each of 23 transcriptional programs; for example, CD49D, HLA-DR and CD32 enrich for GPNMBhigh ("disease associated") microglia. Further, we identify and validate proteins - SIRPA, PDPN and CD162 - that differentiate microglia from infiltrating macrophages. The mCITE-Seq panel enables the transition from RNA-based classification and facilitates the functional characterization and harmonization of model systems.

neuroscience↗

Topoisomerase IIα orchestrates secretion of IL-6 and IL-8 with human papillomavirus replication

High-risk human papillomavirus (HPV) replication requires deregulation of host DNA damage response (DDR) and inflammatory pathways. DNA topoisomerase 2{beta} (Top2{beta}) was previously shown to promote HPV replication, while the function of its paralog Top2 in the viral life cycle remains unknown. Elevated levels of Top2 are consistently observed in cervical intraepithelial lesions and the related carcinomas, as well as in HPV-positive cell lines. Silencing Top2 with shRNA severely suppresses HPV genome maintenance and amplification, but in a DDR-independent manner. Instead, Top2 facilitates secretion of interleukin (IL)-6 and IL-8, which are necessary for HPV replication. Mechanistically, this manipulation is regulated by toll-like receptor 4 (TLR4). Top2 binds to the TLR4 promoter to transcriptionally induce TLR4 expression. Blockade of TLR4 signaling by the specific inhibitor TAK-242 significantly reduces the secreted IL-6/IL-8 levels and HPV replication. Overall, our results reveal a novel role of Top2 to shape the inflammatory microenvironment that benefits HPV replication, making it a promising therapeutic target for HPV-associated diseases. IMPORTANCEHuman papillomaviruses (HPVs) are oncogenic pathogens responsible for many HPV-related diseases such as cervical cancer. HPV replication depends on the subversion of host cellular machineries, particularly pathways governing DNA damage response (DDR) and inflammation. However, the roles of enzymes that directly introduce DNA nicks or mediate strand rejoining remain poorly characterized. Here we highlight a novel role of DNA topoisomerase 2 (Top2) in promoting HPV genome maintenance and amplification but in a DDR-independent manner. Unlike its previously studied paralog Top2{beta}, Top2 supports HPV replication by driving the secretion of inflammatory molecules interleukin (IL)-6 and IL-8, which are critical for the viral genome persistence and copy number expansion. To our knowledge, this is the first evidence that a DDR-associated protein manipulates cytokine secretion, rather than expression, to support HPV replication. Furthermore, blocking toll-like receptor 4 (TLR4) activities significantly reduced Top2-dependent IL-6/IL-8 secretion and impaired HPV replication. These findings establish Top2 as a crucial player in HPV pathogenesis, with a therapeutic potential for treating HPV-associated malignancies.

microbiology↗

Biochemical characterization of cyanobacterial HtpG from Synechococcus elongatus PCC 7942

The 90 kDa Heat Shock Protein (Hsp90) is an essential and highly conserved molecular chaperone that supports the folding and maturation of a diverse array of client proteins across prokaryotic and eukaryotic organisms. In bacteria, HtpG, the Hsp90 homolog, plays a central role in stress response and protein homeostasis, particularly under high-temperature and other stress conditions. Despite extensive studies on HtpG from E. coli, the biochemical properties and functional roles of cyanobacterial HtpG remain poorly characterized. Here, we focus on HtpG from the cyanobacterium Synechococcus elongatus PCC 7942 (seHtpG), a model organism for photosynthesis and circadian rhythm research. We developed a method for the overexpression and purification of seHtpG in E. coli, achieving high purity and yield suitable for biochemical and structural studies. Biophysical and biochemical assays show that seHtpG forms dimers and hydrolyzes ATP and a rate of 1.8 ATP/min, faster than that of E. coli HtpG. This work establishes seHtpG as a model for studying the roles of HtpG in cyanobacterial protein homeostasis, photosynthesis, and stress response, enabling further exploration of cyanobacterial Hsp90 in ecosystem dynamics and biotechnological applications. HighlightsO_LIHtpG from S. elongatus PCC 7942 (seHtpG) was recombinantly overexpressed. C_LIO_LIseHtpG was purified to high homogeneity using chromatography techniques. C_LIO_LILike other members of the Hsp90 family, seHtpG forms a dimeric structure. C_LIO_LIseHtpG exhibits ATPase activity of 1.8 ATP/min at 37{degrees}C. C_LI

biochemistry↗

Presence of Hepatitis B virus infection in colon cancer

Hepatitis B virus (HBV) infection affects [~]300 million people worldwide, which population is at an elevated risk of various cancers, such as gastrointestinal cancer, while the matter behind is largely unclear. In this study, we analyzed 10 colonic specimens from 6 colon cancer patients who were also chronic HBV carriers through Fluorescence-activated Cell Sorting and Immunofluorescence assay to inspect the expression of HBsAg (HBV surface antigen), NTCP (current known cellular receptor of HBV) and CD45 (common marker for immune cells) proteins in single-cell resolution. We found that presence of HBsAg in colonic cells was observed in specimens from all patients, and the proportions of HBV-infected cells were higher in tumors than normal tissues. Strikingly, HBsAg in both immune cells and NTCP-negative cells were also observed in all the patients. In vitro experiments further demonstrated that colonic cells expressing NTCP were indeed highly suspectable to HBV infection. Hence, HBV could infect colonic cells (including immune ones) and may play roles during tumorigenesis in colon cancer.

cancer biology↗