Biology subjects

Chang, W.-C.

Publications and source records attributed to Chang, W.-C..

At least 19 recordsLinked to original sources

bioRxiv2026

Integrated Proteo-Metabolomics of Urinary Extracellular Vesicles Reveals Early Molecular Divergence and Temporal Pathogenesis of Sepsis-Associated AKI

BackgroundSepsis-associated acute kidney injury (S-AKI) is a major contributor to morbidity and mortality in critically ill patients. However, the molecular mechanisms underlying its temporal progression remain poorly understood because conventional biomarkers primarily reflect renal dysfunction rather than disease pathogenesis. Urinary extracellular vesicles (uEVs), which carry kidney-derived molecular cargo, provide a promising platform for monitoring renal-specific biological alterations during disease progression. MethodsWe conducted a longitudinal multi-omics study of uEVs collected from 81 patients with sepsis, including 48 patients with S-AKI and 33 sepsis-only controls. Patients were randomly assigned to a discovery cohort (n = 52) and an independent validation cohort (n = 29). Urine samples were collected at Day 1, Day 4, and Day 8 after AKI diagnosis. High-resolution proteomic and metabolomic profiling was performed to characterize temporal molecular alterations. Enriched pathways identified in the discovery cohort were evaluated in the validation cohort using pathway-level concordance analysis. ResultsComparative analysis between S-AKI and sepsis-only patients identified distinct stage-specific molecular alterations throughout disease progression. At the early stage (Day 1), validated pathways included complement and coagulation cascades, ferroptosis, HIF-1 signaling, sphingolipid metabolism, and arachidonic acid metabolism, highlighting coordinated inflammatory, hypoxic, and lipid metabolic responses. During the mid-stage (Day 4), persistent activation of complement and coagulation cascades, ferroptosis, and HIF-1 signaling was accompanied by metabolic reprogramming involving alanine, aspartate and glutamate metabolism and tyrosine metabolism. Although limited sample availability reduced statistical power at Day 8, phenylalanine metabolism remained validated in the metabolomic analysis, suggesting persistent metabolic dysregulation during late-stage disease progression. ConclusionsThis study provides the first longitudinal, independently validated multi-omics characterization of human uEVs in S-AKI. By integrating proteomic and metabolomic profiling, we reveal the temporal evolution of renal-specific molecular pathways from early inflammatory and hypoxic responses to subsequent metabolic reprogramming. These findings establish uEV-based multi-omics as a promising strategy for molecular phenotyping of S-AKI beyond conventional clinical biomarkers and provide a valuable resource for future biomarker discovery and therapeutic target identification.

biochemistry↗

bioRxiv2026

Meditope-Enabled Chimeric Antigen Receptors Facilitate Plug-and-Play Control of T Cells

Chimeric antigen receptor (CAR) T cells have transformed cancer treatment, yet challenges for achieving broader clinical success remain, including overcoming tumor antigen heterogeneity and limited T cell fitness. To address these challenges and enhance CAR T cell functionality, we leveraged meditope technology, a lock-and-key platform where Fab regions of antibodies are modified to bind a small cyclic peptide termed meditope (meP). We developed a panel of meditope-enabled Fab-based CARs (meCARs), which show selective binding to the meP and comparable activity to traditional single-chain variable fragment (scFv)-based CARs. Focusing on HER2-targeted meCARs for evaluating platform utility, we exploited the modularity of the meditope platform to detect meCAR T cells using meP-fused fluorescent agents, promote meCAR T cell expansion via meP-fused IL-15 cytokine, and broaden tumor antigen targeting through meP-fused antibodies to address tumor heterogeneity. These findings establish the meditope technology as a versatile strategy to augment CAR T cell functionality and overcome key limitations of current CAR-based therapies.

bioengineering↗

bioRxiv2026

IL12-engineered human PSMA-CAR T cells for the treatment of advanced prostate cancer

Adoptive cell therapies used to treat advanced prostate cancer are being developed to target several tumor-associated antigens, including prostate-specific membrane antigen (PSMA). Chimeric antigen receptor (CAR) T cell therapy using the single chain variable fragment (scFv) derived from the humanized murine mAb clone, J591, as the antigen-binding domain has shown promising anti-tumor activity. However, it has also been associated with macrophage activation syndrome and other unwanted toxicities, highlighting the need for more specific and human-derived antigen-binders with optimized construct designs for improved safety and efficacy. Here, we optimize a human scFv-based PSMA-targeted CAR (hPSMA-CAR) with highly selective PSMA targeting. We further introduce a membrane-bound IL-12 (mbIL12) molecule, which enhances potency with increased T cell expansion, IFNy production and anti-tumor cell activity in vitro. Using two clinically-relevant bone-metastatic prostate cancer models, we show that mbIL12-engineered hPSMA-CAR T cells drive potent in vivo anti-tumor responses. In summary, we have developed a promising therapeutic that has potential to promote safe and effective treatment of advanced PSMA+ prostate cancer.

bioengineering↗

bioRxiv2025

Solid tumor CAR T cells engineered with fusion proteins targeting PDL1 for localized IL-12 delivery

CAR T cell efficacy in solid tumors is limited due in part to the immunosuppressive TME. To improve anti-tumor responses, we hypothesized that enabling CAR T cells to secrete bifunctional fusion proteins consisting of a cytokine modifier (e.g., TGF{beta}trap, IL15, or IL12) combined with an immune checkpoint inhibitor (e.g., PDL1) will provide tumor localized immunomodulation to improve CAR T cell functionality. To that end, we engineered CAR T cells to secrete TGF{beta}trap, IL15, or IL12 molecules fused to PDL1 scFv, and assessed in vitro functionality and in vivo safety and efficacy in prostate and ovarian cancer models. CAR T cells engineered with PDL1-IL12 were superior in safety and efficacy compared to CAR T cells alone and to those engineered with PDL1 fused with TGF{beta}trap or IL15. Further, PDL1-IL12 engineered CAR T cells improved T cell trafficking and tumor infiltration, localized IFN{gamma} production, TME modulation, and anti-tumor responses, with reduced systemic inflammation-associated toxicities. We believe our PDL1-IL12 engineering strategy presents an opportunity to improve CAR T cell clinical efficacy and safety across multiple solid tumor types.

bioengineering↗

bioRxiv2025

Specificity Protein 1 is essential for the limb trajectory of ephrin-mediated spinal motor axons

The precise organization of neural circuits requires highly specific axon guidance, facilitated by cell-surface guidance receptors on axonal growth cones that help neurons reach their target destinations. Despite a limited repertoire of known guidance receptors and ligands, neural systems achieve complex axonal networks, suggesting that additional regulatory mechanisms exist. One proposed strategy is the co-expression of ligands and their receptors on the same axons, allowing modulation of receptor responsiveness to guidance cues. To investigate this mechanism, we studied the spinal lateral motor column (LMC) motor neurons, which make a binary axon pathfinding decision toward limb targets. We hypothesized that specificity protein 1 (Sp1), a transcription factor, regulates ephrin expression in LMC neurons, thereby modulating receptor functions via cis-attenuation to ensure accurate axonal pathfinding. Our results show that Sp1 is indeed expressed in LMC neurons during critical axonal extension periods. Manipulating Sp1 activity disrupted LMC axon trajectory selection, and RNA-Seq analysis indicated that Sp1 regulates genes associated with axon guidance, including ephrins. We found that Sp1 knockdown affected ephrin/Eph cis-binding and trans-signaling, highlighting Sp1s role in controlling axonal projections through ephrin gene regulation. Additionally, coactivators p300 and CBP are essential for Sp1s regulatory function. These findings identify Sp1 as a key transcription factor in LMC neurons, essential for ephrin expression and ephrin/Eph-mediated axon guidance, providing insights into the molecular mechanisms of neural circuit formation.

neuroscience↗

bioRxiv2024

Use of Antibody Structural Information in Disease Prediction Models Reveals Antigen Specific B Cell Receptor Sequences in Bulk Repertoire Data

Convergent antibodies are highly similar antibodies elicited in multiple individuals in response to the same antigen. Convergent antibodies provide insight into shared immunological responses and show great promise as diagnostic biomarkers. They have typically been identified using methods that consider the amino acid sequence of the third complementarity-determining region (CDR3) of immunoglobulin heavy chain (IgH). In this study, we extend the definition of convergent antibodies to use structural information about the three IgH CDR regions (CDR1-3). We benchmark the performance of both definitions of convergence by their ability to predict disease status from bulk IgH sequencing data for two different diseases (HIV infection and food sensitization). We show that using predicted structural information outperforms prior approaches for the prediction of food sensitization status and performs on par for HIV infection status. Additionally, the structurally convergent antibody groups driving HIV prediction are from known HIV binders. Thus, the use of structural information allows for the identification of antigen specific antibody groups from bulk IgH sequencing data.

immunology↗

bioRxiv2024

All-trans retinoic acid-mediated ADAR1 degradation synergizes with PD-1 blockade to suppress pancreatic cancer

As a double-stranded RNA-editing enzyme and an interferon-stimulated gene, double-stranded RNA-specific adenosine deaminase (ADAR1) suppresses interferon signaling and contributes to immunotherapy resistance. Suppression of ADAR1 overcomes immunotherapy resistance in preclinical models, but has not yet been translated to clinical settings. By conducting a screening of a subset of the FDA-approved drugs, we found that all-trans retinoic acid (ATRA, also known as tretinoin) caused ADAR1 protein degradation through ubiquitin-proteasome pathways and concomitantly increased PD-L1 expression in pancreatic and breast cancers. In addition, the combination of ATRA and PD-1 blockade reprogrammed the tumor microenvironment and unleashed antitumor immunity and thereby impeded tumor growth in pancreatic cancer mouse models. In a pilot clinical trial, a higher dose of ATRA plus the anti-PD-1 antibody nivolumab prolonged median overall survival in patients with chemotherapy-resistant pancreatic cancer compared to a lower dose of the same regimen. In this study, ATRA was the first drug to be found to cause ADAR1 degradation. We propose translation of a promising 2-pronged antitumor strategy using ATRA and nivolumab to convert immunologically "cold" into "hot" tumors susceptible to immune checkpoint blockade.

cancer biology↗

bioRxiv2024

Inter- and intra-tumor heterogeneous immune presentation in primary uterine carcinosarcoma determined by digital spatial profiling

Uterine carcinosarcoma (UCS) is a rare gynecologic cancer with unfavorable prognosis. Its biphasic histologic components are known to associated with outcomes. Dissecting the tumor heterogeneity within UCS is crucial to discover molecular biomarkers for patient stratification. The aim of this study was to utilize spatial profiling technology to analyze immune presentation in different histological components within UCS tumors. The study included 23 UCS patients whose tumor sections were subjected to nanoString GeoMx Digital Spatial Profiling (DSP) to profile 30 immune-related proteins in 491 segments. We identified distinct cluster-labeled subtypes showing varied immune marker expressions. The immune presentations within the carcinoma and sarcoma components showed significant differences. Markers indicating M2 macrophages (CD45+CD163+) and epithelial-mesenchymal transition (EMT) (SMA, fibronectin) were highly expressed in the sarcoma components. The immune presentation subtypes within each histological component also differed between patients with recurrence in 5 years and without recurrence over 5 years. The cluster-labeled subtype with high Neutrophil/PMN-MDSC marker expression (CD66b) was associated with longer survival, whereas the subtype with high NK cell marker expressions (CD56) was linked to poor prognosis. Our result suggested that immune features within the carcinoma component of UCS tumors would determine patient outcomes and should be considered as a strategy for patient stratification.

immunology↗

bioRxiv2023

B cell repertoire in children with skin barrier dysfunction supports altered IgE maturation associated with allergic food sensitization

IgE B cells produce antibodies responsible for the inappropriate specificity seen in allergic disease. In this study, we sequence antibody gene repertoires from a large, well-characterized early life cohort at risk for developing food allergy. We found that food allergen sensitization was associated with lower IgE mutation frequencies that was abrogated in children living with a pet dog, suggesting potential molecular mechanisms underlying the hygiene hypothesis (i.e., protective effects of pet ownership and non-antiseptic environs reported for allergic disease). We also observed increased IgE diversity and increased isotype-switching to IgE, suggesting that B cell development is altered in those with food allergen sensitizations relative to those without. IgE diversity was even more extreme in subjects who were highly likely to be peanut allergic. Unlike food antigen sensitization, we detected no effect of aeroallergen sensitization on IgE mutation levels and diversity. Consistent patterns of antibody rearrangement were associated with food allergen sensitization. These results have important implications for the allergic response driven by mast cells and basophils and the underlying drivers of the atopic march.

immunology↗

bioRxiv2023

The natural tannins oligomeric proanthocyanidins and punicalagin are potent inhibitors of infection by SARS-CoV-2 in vitro

The COVID-19 pandemic continues to infect people worldwide. While the vaccinated population has been increasing, the rising breakthrough infection persists in the vaccinated population. For living with the virus, the dietary guidelines to prevent virus infection are worthy of and timely to develop further. Tannic acid has been demonstrated to be an effective inhibitor of coronavirus and is under clinical trial. Here we found that two other members of the tannins family, oligomeric proanthocyanidins (OPCs) and punicalagin, are also potent inhibitors against SARS-CoV-2 infection with different mechanisms. OPCs and punicalagin showed inhibitory activity against omicron variants of SARS-CoV-2 infection. The water extractant of the grape seed was rich in OPCs and also exhibited the strongest inhibitory activities for viral entry of wild-type and other variants in vitro. Moreover, we evaluated the inhibitory activity of grape seed extractants (GSE) supplementation against SARS-CoV-2 viral entry in vivo and observed that serum samples from the healthy human subjects had suppressive activity against different variants of SARS-CoV-2 vpp infection after taking GSE capsules. Our results suggest that natural tannins acted as potent inhibitors against SARS-CoV-2 infection, and GSE supplementation could serve as healthy food for infection prevention. HighlightsO_LIOPCs and Punicalagin had inhibitory activity against omicron variants of SARS-CoV-2 infection. C_LIO_LIOPCs serve as a dual inhibitor of the viral Mpro and the cellular TMPRSS2 protease. C_LIO_LIPunicalagin possesses the most potent activity to suppress the Mpro and block the interaction of the viral spike protein and human ACE2. C_LIO_LIOPCs-enriched grape seed extractant exhibited inhibitory activities for viral entry of wild-type and other variants of SARS-CoV-2. C_LIO_LIThe daily intake of grape seed extractants may be able to prevent SARS-CoV-2 infection. C_LI

microbiology↗

bioRxiv2023

Antigen-dependent IL-12 signaling in CAR T cells promotes regional to systemic disease targeting

Chimeric antigen receptor (CAR) T cell therapeutic responses are hampered by limited T cell trafficking, persistence, and durable anti-tumor activity in solid tumor microenvironments. However, these challenges can be largely overcome by relatively unconstrained synthetic engineering strategies, which are being harnessed to improve solid tumor CAR T cell therapies. Here, we describe fully optimized CAR T cells targeting tumor-associated glycoprotein-72 (TAG72) for the treatment of solid tumors, identifying the CD28 transmembrane domain upstream of the 4-1BB co-stimulatory domain as a driver of potent anti-tumor activity and IFN{gamma} secretion. These findings have culminated into a phase 1 trial evaluating safety, feasibility, and bioactivity of TAG72-CAR T cells for the treatment of patients with advanced ovarian cancer (NCT05225363). Preclinically, we found that CAR T cell-mediated IFN{gamma} production facilitated by IL-12 signaling was required for tumor cell killing, which was recapitulated by expressing an optimized membrane-bound IL-12 (mbIL12) molecule on CAR T cells. Critically, mbIL12 cell surface expression and downstream signaling was induced and sustained only following CAR T cell activation. CAR T cells with mbIL12 demonstrated improved antigen-dependent T cell proliferation and potent cytotoxicity in recursive tumor cell killing assays in vitro and showed robust in vivo anti-tumor efficacy in human xenograft models of ovarian cancer peritoneal metastasis. Further, locoregional administration of TAG72-CAR T cells with antigen-dependent IL-12 signaling promoted durable anti-tumor responses against both regional and systemic disease in mice and was associated with improved systemic T cell persistence. Our study features a clinically-applicable strategy to improve the overall efficacy of locoregionally-delivered CAR T cells engineered with antigen-dependent immune-modulating cytokines in targeting both regional and systemic disease.

cancer biology↗

bioRxiv2022

MicroRNA-4776-5p acts as a radiosensitizer and predicts the prognosis of patients with head and neck cancer receiving radiotherapy

Head and neck cancer is the leading cancer worldwide. Radiation therapy plays important role of treatment for head and neck cancer. MicroRNAs have been shown to be related to tumor progression and radiosensitivity. However, the mechanisms are still largely unknown and evidence are still limited. In the current study, we sought to identify the miRNA related the radiosensitivity of head and neck tumor cell, which leading to the disappointed prognosis of patients with head and neck cancer receiving radiation therapy. The miRNA expression profiles and clinical information of patients with head and neck cancer were obtained from The Cancer Genome Atlas. The identification of miRNA was carried out through an integrated bioinformatics analysis. The miRNA identified in previous approach was validated through in vitro and in vivo studies. MiR-4776-5p was finally identified as the role of radio-sensitizer and predicts the prognosis of patients with head and neck cancer receiving radiotherapy. 11 of 16 genes targeted by the miR-4776-5p have been discovered to regulate the mechanisms related to radiosensitivity using functional annotation.

cancer biology↗

bioRxiv2022

The anti-platelet drug cilostazol enhances interrenal steroidogenesis and exerts a scant effect on innate immune responses in zebrafish

RationaleCilostazol, an anti-platelet phosphodiesterase-3 inhibitor used for the treatment of intermittent claudication, is known for its pleiotropic effects on platelets, endothelial cells and smooth muscle cells. However, how cilostazol impacts the endocrine system and the injury-induced inflammatory processes remains unclear. MethodsWe used the zebrafish, a simple transparent model that demonstrates rapid development and a strong regenerative ability, to test whether cilostazol influences steroidogenesis, and the temporal and dosage effects of cilostazol on innate immune cells during tissue damage and repair. ResultsWhile dosages of cilostazol from 10 to 100 M did not induce any noticeable morphological abnormality in the embryonic and larval zebrafish, the heart rate and adrenal/interrenal steroidogenesis in larval zebrafish was increased in a dose-dependent manner. During larval fin amputation and regeneration, cilostazol treatments did not affect the immediate injury-induced recruitment of either neutrophils or macrophages, followed by a subtle yet significant effect on reducing the neutrophil retention at the lesion site. ConclusionsOur results indicate that cilostazol has a significant effect on the growth and endocrine function of steroidogenic tissue; and a limited effect on the neutrophil retention without affecting neutrophil and macrophage recruitment during tissue damage and repair.

pharmacology and toxicology↗

bioRxiv2022

Selective IL13Rα2-Targeted Functionality of IL13-Ligand CARs is Enhanced by Inclusion of 4-1BB Co-Stimulation

ABSTRACTChimeric antigen receptor (CAR) T cell immunotherapy is emerging as a powerful strategy for cancer therapy; however, an important safety consideration is the potential for off-tumor recognition of normal tissue. This is particularly important as ligand-based CARs are optimized for clinical translation. Our group has developed and clinically translated an IL13(E12Y) ligand- based CAR targeting the cancer antigen IL13R2 for treatment of glioblastoma (GBM). There remains limited understanding of how IL13-ligand CAR design impacts the activity and selectivity for the intended tumor-associated target IL13R2 versus the more ubiquitous unintended target IL13R1. In this study, we functionally compared IL13(E12Y)-CARs incorporating different intracellular signaling domains, including first-generation CD3{zeta}- containing CARs (IL13{zeta}), second-generation 4-1BB- (CD137) or CD28-containing CARs (IL13- BB{zeta} or IL13-28{zeta}), and third-generation CARs containing both 4-1BB and CD28 (IL13-28BB{zeta}). In vitro co-culture assays at high tumor burden establish that 2nd generation IL13-BB{zeta} or IL13- 28{zeta} outperform first-generation IL13{zeta} and 3rd generation IL13-28BB{zeta} CAR designs, with IL13- BB{zeta} providing superior CAR proliferation and in vivo anti-tumor potency in human xenograft mouse models. IL13-28{zeta} displayed a lower threshold for antigen recognition, resulting in higher off-target IL13R1 reactivity both in vitro and in vivo. Syngeneic mouse models of GBM also demonstrate safety and anti-tumor potency of murine IL13-BB{zeta} CAR T cells delivered systemically after lymphodepletion. These findings support the use of IL13-BB{zeta} CARs for greater selective recognition of IL13R2 over IL13R1, higher proliferative potential, and superior anti-tumor responsiveness. This study exemplifies the potential of modulating factors outside the antigen targeting domain of a CAR to improve selective tumor recognition..

immunology↗

bioRxiv2020

Pre-conditioning Modifies the Tumor Microenvironment to Enhance Solid Tumor CAR T Cell Efficacy and Endogenous Immunity

Chimeric antigen receptor (CAR) T cell therapy has led to impressive clinical responses in patients with hematological malignancies; however, its utility in patients with solid tumors has been limited. While CAR T cells for the treatment of advanced prostate cancer are being clinically evaluated and are anticipated to show bioactivity, their safety and the impact of the immunosuppressive tumor microenvironment (TME) have not been faithfully explored preclinically. Using a novel human prostate stem cell antigen knock-in (hPSCA-KI) immunocompetent mouse model and syngeneic murine PSCA CAR T cells, we performed analyses of normal and tumor tissues by flow cytometry, immunohistochemistry, and/or RNA sequencing. We further assessed the beneficial impact of cyclophosphamide (Cy) pre-conditioning on modifications to the immunosuppressive TME and impact on PSCA-CAR T cell safety and efficacy. We observed an in vivo requirement of Cy pre-conditioning in uncovering the efficacy of PSCA-CAR T cells in prostate and pancreas cancer models, with no observed toxicities in normal tissues with endogenous PSCA expression. This combination also dampened the immunosuppressive TME, generated pro-inflammatory myeloid and T cell signatures in tumors, and enhanced the recruitment of antigen-presenting cells, and endogenous as well as adoptively-transferred CAR T cells, resulting in long-term anti-tumor immunity.

immunology↗

bioRxiv2020

Chlorotoxin Redirects Chimeric Antigen Receptor T Cells for Specific and Effective Targeting of Glioblastoma

While chimeric antigen receptor (CAR) T cells have demonstrated antitumor activity against glioblastoma (GBM), tumor heterogeneity remains a critical challenge. To more effectively target heterogeneous GBMs, we report the development of a novel peptide-based CAR exploiting the GBM-binding potential of chlorotoxin (CLTX). CLTX bound a greater proportion of tumor cells than GBM-associated antigens EGFR, HER2 and IL13R2. CAR T cells bearing CLTX as the targeting domain (CLTX-CAR), mediated potent in vitro and in vivo anti-GBM activity, and efficiently targeted tumors lacking expression of other GBM-associated antigens. Importantly, CLTX-CAR T cells exhibited no observable off-target effector activity against normal cells, or when adoptively transferred into mice. Effective targeting by CLTX-CAR T cells required cell surface expression of matrix metalloproteinase-2 (MMP-2). Our results are the first demonstration of a peptide toxin utilized as a CAR targeting domain, expanding the repertoire of tumor-selective CAR T cells with the potential to reduce antigen escape. One Sentence SummaryChimeric antigen receptors incorporating chlorotoxin as the tumor targeting domain recognize and kill glioblastoma with high specificity and potency.

immunology↗

bioRxiv2019

Defective cell death of distinct microglial subsets contributes to ADHD-like behavior in mice

Microglia are resident immune cells in the central nervous system that play essential roles to maintain homeostasis and neuronal function. Microglia are heterogeneous cells but the mechanisms by which they contribute to normal brain development remain unclear. Here,we show that microglia in the developing striatum and thalamus undergo pyroptosis,a type of lytic cell death that occurs as a result of Caspase-1 (CASP1) activation downstream of inflammasomes. We observe that pyroptosis occurs in a spatiotemporally regulated and Casp1-dependent manner during fetal brain development. Mice lacking Casp1 or the inflammasome regulating molecules, NLRP3, IL-1R, and Gasdermin D exhibit behavior changes characterized by hyperactivity, inattention, and impulsivity that are similar to attention-deficit/hyperactivity disorder (ADHD). Furthermore, re-expression of Casp1 in Cx3cr1+ cells including microglia restores normal behavior and cell death. We demonstrate that injection of an NLRP3 inhibitor into pregnant wild-type mice is sufficient to induce ADHD-like behaviors in offspring. These data suggest that microglial inflammasome activation and pyroptosis are essential for normal brain development and that genetic and pharmacological disruptions in this pathway may represent new ADHD risk factors.

neuroscience↗

bioRxiv2019

TET1 and TDG suppress intestinal tumorigenesis by down regulating the inflammatory and immune response pathways

IntroductionAberrant DNA methylation is frequently observed in colorectal cancer (CRC), but the underlying mechanisms are poorly understood. Ten-Eleven Translocation (TET) dioxygenases and DNA repair enzyme Thymine DNA Glycosylase (TDG) are involved in active DNA demethylation by generating and removing, respectively, novel oxidized cytosine species. Mutations of TET1 and TDG, and alterations of the levels of oxidized cytosine species have been identified in human CRC cases, but the biological significance of the TET-TDG demethylation axis in intestinal tumorigenesis is unclear.\n\nMaterial and MethodsWe generated ApcMin mice with additional inactivation of Tet1 and/or Tdg, and characterized the methylome and transcriptome of intestinal adenomas by DREAM and RNA sequencing, respectively.\n\nResultsTet1- and/or Tdg-deficient ApcMin mice show enhanced intestinal tumorigenesis in comparison to wild type Tet1 and Tdg ApcMin mice. Specifically, Tet1 and/or Tdg-deficient ApcMin adenomas manifested increased size or features of erosion and stroma activation. Methylome analysis revealed progressive loss of global DNA hypomethylation in colonic adenomas from Tet1- and Tdg-deficient ApcMin mice, and hypermethylation of CpG islands in Tet1-deficient ApcMin mice. In addition, RNA sequencing showed upregulation of genes in inflammatory and immune response pathways in Tet1-and Tdg-mutant colonic adenomas compared to control ApcMin adenomas.\n\nConclusionsTaken together, these findings demonstrate the important role of active DNA demethylation mediated by TET-TDG in reducing intestinal tumor formation, by modulating the epigenome and inflammatory/immune responses. This study highlights a novel mechanism of epigenetic deregulation during intestinal tumorigenesis with diagnostic, therapeutic and prognostic implications.

cancer biology↗