Gastroenterology
Abstract
Hypertonic and hyperosmolar stimuli frequently pose challenges to the intestinal tract. Therefore, a resilient epithelial barrier is essential for maintaining gut homeostasis in the presence of osmotic perturbations. NFAT5, an osmosensitive transcription factor, primarily maintains cellular homeostasis under hypertonic conditions. However, the osmoprotective role of NFAT5 in enterocyte homeostasis is poorly understood. Here, we demonstrate that NFAT5 is critical for the survival and proliferation of intestinal epithelial cells (IECs) and that its deficiency accelerates chemically induced or spontaneous colitis in mice. Mechanistically, NFAT5 promotes the survival of IECs and the renewal of intestinal stem cells, thereby regulating the production of mucus and antimicrobial compounds, including RegIII and lysozyme, which consequently shape the gut microbial composition to prevent colitis. Transcriptome analysis identifies HSP70 as a key downstream target of NFAT5 in epithelial regeneration. Loss- and gain-of-function experiments of HSP70 revealed that NFAT5 mitigates experimental colitis through IEC Hsp70, which protected stem cells from inflammation-induced injury and maintained barrier function. In conclusion, our study demonstrates a previously unknown role for NFAT5 in dictating the crosstalk between intestinal stem cells and the microbiota, underscoring the importance of the NFAT5–HSP70 axis in maintaining epithelial regeneration related to gut barrier function, balancing microbial composition, and subsequently preventing colitis progression.
Authors
Se Hyeon Park, Dae Hee Cheon, Yu-Mi Kim, Yeji Choi, Yong-Joon Cho, Bong-Ki Hong, Sang-Hyun Cho, Mi‑Na Kweon, Hyug Moo Kwon, Eugene B. Chang, Donghyun Kim, Wan-Uk Kim
Abstract
Somatic mutations that increase clone fitness or resist disease are positively selected, but the impact of these mutations on organismal health remains unclear. We previously showed that Tbx3 deletion increases hepatocyte fitness within fatty livers. Here, we detected TBX3 somatic mutations in patients with metabolic dysfunction-associated steatotic liver disease (MASLD). In mice, Tbx3 deletion protected against, whereas Tbx3 overexpression exacerbated MASLD. Tbx3 deletion reduced lipid overload by accelerating VLDL secretion. Choline deficient diets, which block VLDL secretion, abrogated this protective effect. TBX3 transcriptionally suppressed the conventional secretory pathway and cholesterol biosynthesis. Hdlbp is a direct target of TBX3 that is responsible for the altered VLDL secretion. In contrast to wild-type TBX3, the TBX3 I155S and A280S mutations found in patients failed to suppress VLDL secretion. In conclusion, TBX3 mutant clones expand during MASLD through increased lipid disposal, demonstrating that clonal fitness can benefit the liver at the cost of hyperlipidemia.
Authors
Gregory Mannino, Gabriella Quinn, Min Zhu, Zixi Wang, Xun Wang, Boyuan Li, Meng-Hsiung Hsieh, Thomas Mathews, Lauren Zacharias, Wen Gu, Purva Gopal, Natalia Brzozowska, Peter Campbell, Matt Hoare, Glen Liszczak, Hao Zhu
Abstract
Perianal fistulizing Crohn’s disease (PCD) is a common and debilitating complication with elusive pathophysiology. To define actionable immunologic targets in PCD, we recruited patients with PCD (n = 24), CD without perianal disease (NPCD, n = 10), and idiopathic/cryptoglandular perianal fistulas (IPF, n = 29). Biopsies from fistula tracts, fistula opening, and rectal mucosa were analyzed using single-cell RNA-sequencing (scRNA-seq), mass cytometry (CyTOF), and spatial transcriptomics (ST). Global hyperactivation of IFN-g pathways distinguished PCD from idiopathic perianal fistulas and CD without perianal disease in the fistula tracts and/or intestinal mucosa. IFN-g and TNF-a signaling directly induced genes involved in epithelial-to-mesenchymal transition in PCD rectal epithelial cells. Enhanced IFN-g signaling in PCD was driven by pathogenic Th17 (pTh17) cells, which were recruited and activated by myeloid cells overexpressing LPS signature (LPS_myeloid). pTh17 and LPS_myeloid cells co-localized adjacent to PCD fistula tracts on ST and drove local IFN-g signaling. Anti-TNFs facilitated fistula healing by downregulating T and myeloid cell signatures, while promoting mucosal barrier repair and immunoregulatory processes. Key single-cell findings were validated by bulk RNA-seq data of an independent CD cohort. To summarize, we identified IFN-g-driven mechanisms contributing to pathogenesis and highlighted its blockade as a therapeutic strategy for PCD.
Authors
Siyan Cao, Khai M. Nguyen, Kaiming Ma, Tingyi Tan, Xin Yao, Ta-Chiang Liu, Malek Ayoub, Jalpa Devi, Sami Samaan, Yizhou Liu, Radhika Smith, Matthew L. Silviera, Steven R. Hunt, Paul E. Wise, Matthew G. Mutch, Sean C. Glasgow, William C. Chapman Jr, Michelle L. Cowan, Mathew A. Ciorba, Marco Colonna, Parakkal Deepak
Abstract
Esophageal adenocarcinoma (EA) is increasingly prevalent and is thought to arise from Barrett’s esophagus (BE), a metaplastic condition in which chronic acid and bile reflux transforms the esophageal squamous epithelium into a gastric-intestinal glandular mucosa. The molecular determinants driving this metaplasia are poorly understood. We developed a human BE organoid biobank that recapitulates BE’s molecular heterogeneity. Bulk and single-cell transcriptomics, supported by patient tissue analysis, revealed that BE differentiation reflects a balance between SOX2 (foregut/esophageal) and CDX2 (hindgut/intestinal) transcription factors. Using squamous-specific inducible Sox2 knockout (Krt5CreER/+; Sox2∆/∆; ROSA26tdTomato/+) mice, we observed increased basal proliferation, reduced squamous differentiation, and expanded metaplastic glands at the squamocolumnar junction, some tracing back to Krt5-expressing cells. CUT&RUN analysis showed SOX2 bound and promoted differentiation-associated (e.g., Krt13) and repressed proliferation-associated (e.g., Mki67) targets. Thus, SOX2 is critical for foregut squamous epithelial differentiation and its decreased expression is likely an initiating step in progression to BE and thence to EA.
Authors
Ramon U. Jin, Yuanwei Xu, Tung-Shing Lih, Yang-Zhe Huang, Toni M. Nittolo, Blake E. Sells, Olivia M. Dres, Jean S. Wang, Qing Kay Li, Hui Zhang, Jason C. Mills
Abstract
Mutations in Polybromo 1 (PBRM1), a subunit of the switch/sucrose nonfermentable (SWI/SNF) chromatin remodeling complex, are frequently observed in several cancers, including pancreatic ductal adenocarcinoma (PDAC). In this study, we demonstrated that pancreas-specific loss of Pbrm1 in mice harboring Kras mutations and Trp53 deletions accelerated the development of poorly differentiated PDAC, epithelial-mesenchymal transition (EMT), and metastasis, resulting in worsened prognosis. Pbrm1 loss in preexisting PDAC shifted the tumor grade from a well- to a poorly differentiated state and elevated vimentin expression. Pbrm1-null PDAC exhibited downregulation of apical junction genes and upregulation of EMT pathway genes, including the vimentin and squamous molecular subtype signature genes. Mechanistically, PBRM1 bound to the vimentin gene promoter and directly downregulated its expression. Furthermore, suppression of vimentin in Pbrm1-null PDAC cells reversed the dedifferentiation phenotype and reduced EMT and metastasis. Consistently, reduced PBRM1 expression correlated with high vimentin expression, poorly differentiated histology, a high recurrence rate, and reduced overall survival in human PDACs. Additionally, PDAC with PBRM1 deletion was associated with the aggressive squamous molecular subtype. Our data established PBRM1 as a tumor suppressor that controls tumor grade and metastasis of PDAC by regulating vimentin expression.
Authors
Munenori Kawai, Akihisa Fukuda, Munehiro Ikeda, Kei Iimori, Kenta Mizukoshi, Kosuke Iwane, Go Yamakawa, Mayuki Omatsu, Mio Namikawa, Makoto Sono, Tomonori Masuda, Yuichi Fukunaga, Munemasa Nagao, Osamu Araki, Takaaki Yoshikawa, Satoshi Ogawa, Yukiko Hiramatsu, Motoyuki Tsuda, Takahisa Maruno, Yuki Nakanishi, Dieter Saur, Tatsuaki Tsuruyama, Toshihiko Masui, Etsuro Hatano, Hiroshi Seno
Abstract
Mechanisms by which mucosal regeneration is abrogated in inflammatory bowel disease (IBD) are still under investigation, and a role for an intestinal stem cell (ISC) defect is now emerging. Herein, we report an abnormal ISC death that occurs in Crohn’s disease, which exacerbates colitis, limits ISC-dependent mucosal repair, and is controlled through the death factor Transmembrane protein 219 (TMEM219). Large alterations in TMEM219 expression were observed in patients with Crohn’s disease, particularly in those with active disease and/or those who were nonresponders to conventional therapy, confirming that TMEM219 signaling is abnormally activated and leads to failure of the mucosal regenerative response. Mechanistic studies revealed a proapoptotic TMEM219-mediated molecular signature in Crohn’s disease, which associates with Caspase-8 activation and ISC death. Pharmacological blockade of the IGFBP3/TMEM219 binding/signal with the recombinant protein ecto-TMEM219 restored the self-renewal abilities of miniguts generated from patients with Crohn’s disease in vitro and ameliorated DSS-induced and T cell-mediated colitis in vivo, ultimately leading to mucosal healing. Genetic tissue-specific deletion of TMEM219 in ISCs in newly generated TMEM219fl/flLGR5cre mice revived their mucosal regenerative abilities both in vitro and in vivo. Our findings demonstrate that a TMEM219-dependent ISC death exacerbates colitis and that TMEM219 blockade reestablishes intestinal self-renewal properties in IBD.
Authors
Francesca D’Addio, Giovanni Amabile, Emma Assi, Anna Maestroni, Adriana Petrazzuolo, Cristian Loretelli, Ahmed Abdelasalam, Moufida Ben Nasr, Ida Pastore, Maria Elena Lunati, Vera Usuelli, Monica Zocchi, Andy Joe Seelam, Domenico Corradi, Stefano La Rosa, Virna Marin, Monique Zangarini, Marta Nardini, Stefano Porzio, Filippo Canducci, Claudia Nardini, Basset El Essawy, Manuela Nebuloni, Jun Yang, Massimo Venturini, Giovanni Maconi, Franco Folli, Silvio Danese, Gianvincenzo Zuccotti, Gianluca M. Sampietro, Sandro Ardizzone, Paolo Fiorina
Abstract
Alcohol-associated liver disease represents a significant global health challenge, with gut microbial dysbiosis and bacterial translocation playing a critical role in its pathogenesis. Patients with alcohol-associated hepatitis had increased fecal abundance of mammalian viruses including retroviruses. This study investigated the role of endogenous retroviruses (ERVs) in the development of alcohol-associated liver disease. Transcriptomic analysis of duodenal and liver biopsies revealed increased expression of several human ERVs, including HERV-K and HERV-H, in patients with alcohol-associated liver disease compared with controls. Chronic-binge ethanol feeding markedly induced ERV abundance in intestinal epithelial cells, but not the liver of mice. Ethanol increased ERV expression and activated the Z-DNA binding protein 1 (Zbp1)–mixed lineage kinase domain-like pseudokinase (Mlkl) signaling pathways to induce necroptosis in intestinal epithelial cells. Antiretroviral treatment reduced ethanol-induced intestinal ERV expression, stabilized the gut barrier, and decreased liver disease in microbiota-humanized mice. Furthermore, mice with an intestine-specific deletion of Zbp1 were protected against bacterial translocation and ethanol-induced steatohepatitis. These findings indicate that ethanol exploits this pathway by inducing ERVs and promoting innate immune responses, which results in the death of intestinal epithelial cells, gut barrier dysfunction and liver disease. Targeting the ERV-Zbp1 pathway may offer new therapies for patients with alcohol-associated liver disease.
Authors
Noemí Cabré, Marcos F. Fondevila, Wenchao Wei, Tomoo Yamazaki, Fernanda Raya Tonetti, Alvaro Eguileor, Ricard Garcia-Carbonell, Abraham S. Meijnikman, Yukiko Miyamoto, Susan Mayo, Yanhan Wang, Xinlian Zhang, Thorsten Trimbuch, Seija Lehnardt, Lars Eckmann, Derrick E. Fouts, Cristina Llorente, Hidekazu Tsukamoto, Peter Stärkel, Bernd Schnabl
Abstract
Authors
Michaela A.A. Fuchs, Myles Wolf
Abstract
The Wnt/β-catenin pathway regulates expression of the SOX9 gene, which encodes SRY-box transcription factor 9, a differentiation factor and potential β-catenin regulator. Because APC tumor suppressor defects in ~80% of colorectal cancers (CRCs) activate the Wnt/β-catenin pathway, we studied SOX9 inactivation in CRC biology. Compared to effects of Apc inactivation in mouse colon tumors, combined Apc and Sox9 inactivation instigated more invasive tumors with epithelial-mesenchymal transition (EMT) and SOX2 stem cell factor upregulation. In an independent mouse CRC model with combined Apc, Kras, and Trp53 defects, Sox9 inactivation promoted SOX2 induction and distant metastases. About 20% of 171 human CRCs showed loss of SOX9 protein expression, which correlated with higher tumor grade. In an independent group of 376 CRC patients, low SOX9 gene expression was linked to poor survival, earlier age at diagnosis, and increased lymph node involvement. SOX9 expression reductions in human CRC were linked to promoter methylation. EMT pathway gene expression changes were prominent in human CRCs with low SOX9 expression and in a mouse cancer model with high SOX2 expression. Our results indicate SOX9 has tumor suppressor function in CRC; its loss may promote progression, invasion, and poor prognosis by enhancing EMT and stem cell phenotypes.
Authors
Ying Feng, Ningxin Zhu, Karan Bedi, Jinju Li, Chamila Perera, Maranne Green, Naziheh Assarzadegan, Yali Zhai, Qingzhi Liu, Veerabhadran Baladandayuthapani, Jason R. Spence, Kathleen R. Cho, Eric R. Fearon
Abstract
Colorectal cancer (CRC) is characterized by an immune-suppressive microenvironment that contributes to tumor progression and immunotherapy resistance. The gut microbiome produces diverse metabolites that feature unique mechanisms of interaction with host targets, yet the role of many metabolites in CRC remains poorly understood. In this study, the microbial metabolite 4-hydroxybenzeneacetic acid (4-HPA) promoted the infiltration of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) in the tumor microenvironment, consequently inhibiting the anti-tumor response of CD8+ T cells and promoting CRC progression in vivo. Mechanistically, 4-HPA activates the JAK2/STAT3 pathway, which upregulates CXCL3 transcription, thereby recruiting PMN-MDSCs to the CRC microenvironment. Selective knockdown of CXCL3 re-sensitized tumors to anti-PD1 immunotherapy in vivo. Chlorogenic acid (CGA) reduces the production of 4-HPA by microbiota, likewise abolishing 4-HPA-mediated immunosuppression. The 4-HPA content in CRC tissues was notably increased in patients with advanced CRC. Overall, the gut microbiome uses 4-HPA as a messenger to control chemokine-dependent accumulation of PMN-MDSC cells and regulate anti-tumor immunity in CRC. Our findings provide a scientific basis for establishing clinical intervention strategies to reverse the tumor immune microenvironment and improve the efficacy of immunotherapy by reducing the interaction between intestinal microbiota, tumor cells and tumor immune cells.
Authors
Qing Liao, Ximing Zhou, Ling Wu, Yuyi Yang, Xiaohui Zhu, Hangyu Liao, Yujie Zhang, Weidong Lian, Feifei Zhang, Hui Wang, Yanqing Ding, Liang Zhao
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)