Hepatology
Abstract
Steatotic liver enhances liver metastasis of colorectal cancer, but this process is not fully understood. Steatotic liver induced by a high-fat diet (HFD) increases cancer-associated fibroblast (CAF) infiltration and collagen and hyaluronic acid (HA) production. We investigated the role of HA synthase 2 (HAS2) in the fibrotic tumor microenvironment in steatotic liver using Has2ΔHSC mice, in which Has2 is deleted from hepatic stellate cells. Has2ΔHSC mice had reduced steatotoic liver-associated metastatic tumor growth of MC38 colorectal cancer cells, collagen and HA deposition, and CAF and M2 macrophage infiltration. We found low-molecular-weight HA activates yes-associated protein (YAP) in cancer cells, which then releases connective tissue growth factor to further activate CAFs for HAS2 expression. Single-cell analyses revealed a link between CAF-derived HAS2 with M2 macrophages and colorectal cancer cells through CD44; these cells associated with exhausted CD8 T cells via programmed death-ligand 1 and programmed cell death protein 1. The HA synthesis inhibitors reduced steatotic liver-associated metastasis of colorectal cancer, YAP expression, CAF and M2 macrophage infiltration. In conclusion, steatotic liver modulates a fibrotic tumor microenvironment to enhance metastatic cancer activity through a bidirectional regulation between CAFs and metastatic tumors, enhancing the metastatic potential of colorectal cancer in the liver.
Authors
Yoon Mee Yang, Jieun Kim, Zhijun Wang, Jina Kim, So Yeon Kim, Gyu Jeong Cho, Jee Hyung Lee, Sun Myoung Kim, Takashi Tsuchiya, Michitaka Matsuda, Vijay Pandyarajan, Stephen J. Pandol, Michael S. Lewis, Alexandra Gangi, Paul W. Noble, Dianhua Jiang, Akil Merchant, Edwin M. Posadas, Neil A. Bhowmick, Shelly C. Lu, Sungyong You, Alexander M. Xu, Ekihiro Seki
Abstract
Spontaneous clearance of hepatitis B virus (HBV) is frequent in adults (95%) but rare in infants (5%), emphasizing the critical role of age-related hepatic immunocompetence. However, the underlying mechanisms of hepatocyte-specific immunosurveillance and age-dependent HBV clearance remain unclear. Here, we identified PGLYRP2 as a hepatocyte-specific pattern recognition receptor with age-dependent expression, and demonstrated that phase separation of PGLYRP2 was a critical driver of spontaneous HBV clearance in hepatocytes. Mechanistically, PGLYRP2 recognized and potentially eliminated covalently closed circular DNA (cccDNA) via phase separation, coordinated by its intrinsically disordered region and HBV DNA-binding domain (PGLYRP2IDR/209-377) in the nucleus. Additionally, PGLYRP2 suppressed HBV capsid assembly by directly interacting with the viral capsid, mediated by its PGRP domain. This interaction promoted the nucleocytoplasmic translocation of PGLYRP2 and subsequent secretion of the PGLYRP2-HBV capsid complex, thereby bolstering the hepatic antiviral response. Pathogenic variants or deletions in PGLYRP2 impaired its ability to inhibit HBV replication, highlighting its essential role in hepatocyte-intrinsic immunity. These findings suggest that targeting the PGLYRP2-mediated host-virus interaction may offer a potential therapeutic strategy for the development of anti-HBV treatments, representing a promising avenue for achieving a functional cure for HBV infection.
Authors
Ying Li, Huihui Ma, Yongjian Zhang, Tinghui He, Binyang Li, Haoran Ren, Jia Feng, Jie Sheng, Kai Li, Yu Qian, Yunfeng Wang, Haoran Zhao, Jie He, Huicheng Li, Hongjin Wu, Yuanfei Yao, Ming Shi
Abstract
Understanding cell fate regulation in the liver is necessary to advance cell therapies for hepatic disease. Liver progenitor cells (LPC) contribute to tissue regeneration after severe hepatic injury yet signals instructing progenitor cell dynamics and fate are largely unknown. The Tissue Inhibitor of Metalloproteinases, TIMP1 and TIMP3 control the sheddases ADAM10 and ADAM17, key for NOTCH activation. Here we uncover the role of the TIMP/ADAM/NOTCH/DLK1 axis in LPC maintenance and cholangiocyte specification. Combined TIMP1/TIMP3 loss in vivo caused abnormal portal triad stoichiometry accompanied by collagen deposits, dysregulated Notch signalling and increased soluble DLK1. The MIC1-1C3+CD133+CD26– biliary progenitor population was reduced following acute CCl4 or chronic DDC liver injury and in aged TIMP deficient livers. ScRNA-seq data interrogation and RNAscope identified portal mesenchymal cells co-expressing ADAM17/DLK1 as enzymatically equipped to process DLK1 and direct LPC differentiation. Specifically, TIMP deficient biliary fragment-derived organoids displayed increased propensity for cholangiocyte differentiation. ADAM17 inhibition reduced Sox9-mediated cholangiocyte differentiation, prolonging organoid growth and survival, whereas soluble DLK1-treated WT organoids triggered Sox9 expression and cholangiocyte specification in mouse and patient-derived liver organoids. Thus, metalloprotease inhibitors regulate instructive signals for biliary cell differentiation and LPC preservation within the portal niche, providing a new basis for cell therapy strategies.
Authors
Virginie Defamie, Kazeera Aliar, Soumili Sarkar, Foram Vyas, Ronak Shetty, Swami Reddy Narala, Hui Fang, Sanjay Saw, Pirashaanthy Tharmapalan, Otto Sanchez, Jennifer J. Knox, Paul D. Waterhouse, Rama Khokha
Abstract
Dysfunctional adipose tissue is believed to promote the development of hepatic steatosis and systemic insulin resistance, but many of the mechanisms involved are still unclear. Lipin 1 catalyzes the conversion of phosphatidic acid to diacylglycerol (DAG), the penultimate step of triglyceride synthesis, which is essential for lipid storage. Herein we found that adipose tissue LPIN1 expression is decreased in people with obesity compared to lean subjects, and low LPIN1 expression correlated with multi-tissue insulin resistance and increased rates of hepatic de novo lipogenesis. Comprehensive metabolic and multi-omic phenotyping demonstrated that adipocyte-specific Lpin1–/– mice had a metabolically-unhealthy phenotype, including liver and skeletal muscle insulin resistance, hepatic steatosis, increased hepatic de novo lipogenesis, and transcriptomic signatures of metabolically associated steatohepatitis that was exacerbated by high-fat diets. We conclude that adipocyte lipin 1-mediated lipid storage is vital for preserving adipose tissue and systemic metabolic health, and its loss predisposes mice to metabolically associated steatohepatitis.
Authors
Andrew LaPoint, Jason M. Singer, Daniel Ferguson, Trevor M. Shew, M. Katie Renkemeyer, Hector H. Palacios, Rachael L. Field, Sireeesha Yerrathota, Roshan Kumari, Mahalakshmi Shankaran, Gordon I. Smith, Jun Yoshino, Mai He, Gary J. Patti, Marc K. Hellerstein, Samuel Klein, E. Matthew Morris, Jonathan R. Brestoff, Brian N. Finck, Andrew Lutkewitte
Abstract
Activated mTORC2/AKT signaling plays a role in hepatocellular carcinoma (HCC). Research has shown that TSC/mTORC1 and FOXO1 are distinct downstream effectors of AKT signaling in liver regeneration and metabolism. However, the mechanisms by which these pathways mediate mTORC2/AKT activation in HCC are not yet fully understood. Amplification and activation of c-MYC is a key molecular event in HCC. In this study, we explored the roles of TSC/mTORC1 and FOXO1 as downstream effectors of mTORC2/AKT1 in c-MYC-induced hepatocarcinogenesis. Using various genetic approaches in mice, we found that manipulating the FOXO pathway had minimal impact on c-MYC-induced HCC. In contrast, loss of mTORC2 inhibited c-MYC-induced HCC, an effect that was completely reversed by ablating TSC2, which activated mTORC1. Additionally, we discovered that p70/RPS6 and 4EBP1/eIF4E act downstream of mTORC1, regulating distinct molecular pathways. Notably, the 4EBP1/eIF4E cascade is crucial for cell proliferation and glycolysis in c-MYC-induced HCC. We also identified centromere protein M (CENPM) as a downstream target of the TSC2/mTORC1 pathway in c-MYC-driven hepatocarcinogenesis, and its ablation entirely inhibited c-MYC-dependent HCC formation. Our findings demonstrate that the TSC/mTORC1/CENPM pathway, rather than the FOXO cascade, is the primary signaling pathway regulating c-MYC-driven hepatocarcinogenesis. Targeting CENPM holds therapeutic potential for treating c-MYC-driven HCC.
Authors
Yi Zhou, Shu Zhang, guoteng Qiu, Xue Wang, Andrew Yonemura, Hongwei Xu, Guofei Cui, Shanshan Deng, Joanne Chun, Nianyong Chen, Meng Xu, Xinhua Song, Jingwen Wang, Zijing Xu, Youping Deng, Matthias Evert, Diego F. Calvisi, Shumei Lin, Haichuan Wang, Xin Chen
Abstract
The burden of senescent hepatocytes correlates with MASLD severity but mechanisms driving senescence, and how it exacerbates MASLD are poorly understood. Hepatocytes become senescent when Smoothened (Smo) is deleted to disrupt Hedgehog signaling. We aimed to determine if the secretomes of Smo-deficient hepatocytes perpetuate senescence to drive MASLD progression. RNA seq analysis confirmed that hepatocyte populations of MASLD livers are depleted of Smo(+) cells and enriched with senescent cells. When fed CDA-HFD, Smo(-) mice had lower antioxidant markers and developed worse DNA damage, senescence, MASH and liver fibrosis than Smo(+) mice. Sera and hepatocyte-conditioned medium from Smo(-) mice were depleted of thymidine phosphorylase (TP), a protein that maintains mitochondrial fitness. Treating Smo(-) hepatocytes with TP reduced senescence and lipotoxicity; inhibiting TP in Smo(+) hepatocytes had the opposite effects and exacerbated hepatocyte senescence, MASH, and fibrosis in CDA-HFD-fed mice. Therefore, we found that inhibiting Hedgehog signaling in hepatocytes promotes MASLD by suppressing hepatocyte production of proteins that prevent lipotoxicity and senescence.
Authors
Ji Hye Jun, Kuo Du, Rajesh Kumar Dutta, Raquel Maeso-Diaz, Seh-hoon Oh, Liuyang Wang, Guannan Gao, Ana Ferreira, Jon Hill, Steven S. Pullen, Anna Mae Diehl
Abstract
Authors
Dan Wang, Ania Baghoomian, Zhengyi Zhang, Ya Cui, Emily C. Whang, Xiang Li, Josue Fraga, Rachel Spellman, Tien S. Dong, We Li, Arpana Gupta, Jihane N. Benhammou, Tamer Sallam
Abstract
Neutrophil infiltration occurs in a variety of liver diseases, but it is unclear how neutrophils and hepatocytes interact. Neutrophils generally use granule proteases to digest phagocytosed bacteria and foreign substances or neutralize them in neutrophil extracellular traps. In certain pathological states, granule proteases play a destructive role against the host as well. More recently, non-destructive actions of neutrophil granule proteins have been reported, such as modulation of tissue remodeling and metabolism. Here we report a completely different mechanism by which neutrophils act non-destructively, by inserting granules directly into hepatocytes. Specifically, elastase-containing granules were transferred to hepatocytes where elastase selectively degraded intracellular calcium channels to reduce cell proliferation without cytotoxicity. In response, hepatocytes increased expression of serpin E2 and A3, which inhibited elastase activity. Elastase insertion was seen in patient specimens of alcohol-associated hepatitis, and the relationship between elastase-mediated ITPR2 degradation and reduced cell proliferation was confirmed in mouse models. Moreover, neutrophils from patients with alcohol-associated hepatitis were more prone to degranulation and more potent in reducing calcium channel expression than neutrophils from healthy subjects. This non-destructive and reversible action on hepatocytes defines a previously unrecognized role for neutrophils in the transient regulation of epithelial calcium signaling mechanisms.
Authors
Noriyoshi Ogino, M. Fátima Leite, Mateus T. Guerra, Emma Kruglov, Hiromitsu Asashima, David A. Hafler, Takeshi Ito, João P. Pereira, Brandon J. Peiffer, Zhaoli Sun, Barbara E. Ehrlich, Michael H. Nathanson
Abstract
It is unknown which post-transcriptional regulatory mechanisms are required for oncogenic competence. Here, we show that the LIN28 family of RNA-binding proteins (RBPs), which facilitate post-transcriptional RNA metabolism within ribonucleoprotein networks, are essential for the initiation of diverse oncotypes of hepatocellular carcinoma (HCC). In HCC models driven by NRASG12V/Tp53, CTNNB1/YAP/Tp53, or AKT/Tp53, mice without Lin28a and Lin28b were markedly impaired in cancer initiation. We biochemically defined an oncofetal regulon of 15 factors connected to Lin28 through direct mRNA and protein interactions. Interestingly, all were RBPs and only 1 of 15 is a Let-7 target. Polysome profiling and reporter assays showed that LIN28B directly increased the translation of 8 of these 15 RBPs. As expected, overexpression of LIN28B and IGFBP1-3 were able to genetically rescue cancer initiation. Using this platform to probe components downstream of LIN28, we found that 8 target RBPs were able to restore NRASG12V/Tp53 cancer formation in Lin28a/b deficient mice. Furthermore, these LIN28B targets promote cancer initiation through an increase in protein synthesis. LIN28B, central to an RNP regulon that increases translation of RBPs, is important for tumor initiation in the liver.
Authors
Meng-hsiung Hsieh, Yonglong Wei, Lin Li, Liem H. Nguyen, Yu-Hsuan Lin, Jung M. Yoon, Xuxu Sun, Xun Wang, Xin Luo, Sarah K. Knutson, Christina Bracken, George Q. Daley, John T. Powers, Hao Zhu
Abstract
Metabolic dysfunction–associated steatohepatitis (MASH) — previously described as nonalcoholic steatohepatitis (NASH) — is a major driver of liver fibrosis in humans, while liver fibrosis is a key determinant of all-cause mortality in liver disease independent of MASH occurrence. CCAAT/enhancer binding protein α (CEBPA), as a versatile ligand-independent transcriptional factor, has an important function in myeloid cells, and is under clinical evaluation for cancer therapy. CEBPA is also expressed in hepatocytes and regulates glucolipid homeostasis; however, the role of hepatocyte-specific CEBPA in modulating liver fibrosis progression is largely unknown. Here, hepatic CEBPA expression was found to be decreased during MASH progression both in humans and mice, and hepatic CEBPA mRNA was negatively correlated with MASH fibrosis in the human liver. CebpaΔHep mice had markedly enhanced liver fibrosis induced by a high-fat, high-cholesterol, high-fructose diet or carbon tetrachloride. Temporal and spatial hepatocyte-specific CEBPA loss at the progressive stage of MASH in CebpaΔHep,ERT2 mice functionally promoted liver fibrosis. Mechanistically, hepatocyte CEBPA directly repressed Spp1 transactivation to reduce the secretion of osteopontin, a fibrogenesis inducer of hepatic stellate cells. Forced hepatocyte-specific CEBPA expression reduced MASH-associated liver fibrosis. These results demonstrate an important role for hepatocyte-specific CEBPA in liver fibrosis progression, and may help guide the therapeutic discoveries targeting hepatocyte CEBPA for the treatment of liver fibrosis.
Authors
Tingting Yan, Nana Yan, Yangliu Xia, Vorthon Sawaswong, Xinxin Zhu, Henrique Bregolin Dias, Daisuke Aibara, Shogo Takahashi, Keisuke Hamada, Yoshifumi Saito, Guangming Li, Hui Liu, Hualong Yan, Thomas J. Velenosi, Kristopher W. Krausz, Jing Huang, Shioko Kimura, Yaron Rotman, Aijuan Qu, Haiping Hao, Frank J. Gonzalez
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)