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Yamanaka T, Araki K, Yokobori T, Muranushi R, Hoshino K, Hagiwara K, Gantumur D, Ishii N, Tsukagoshi M, Watanabe A, Harimoto N, Masamune A, Uojima H, Mizokami M, Ito K, Shirabe K. Potential of Mac-2-binding protein glycan isomer as a new therapeutic target in pancreatic cancer. Cancer Sci 2024; 115:1241-1249. [PMID: 38321872 PMCID: PMC11007056 DOI: 10.1111/cas.16087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 12/08/2023] [Accepted: 12/22/2023] [Indexed: 02/08/2024] Open
Abstract
Pancreatic cancer (PC) is a challenging malignancy to treat. Mac-2-binding protein glycan isomer (M2BPGi) is a novel serum marker of liver fibrosis and hepatocellular carcinoma and is secreted by hepatic stellate and stroma cells. Serum M2BPGi levels are upregulated in PC patients. We measured the expression of M2BPGi in the serum of 27 PC patients and determined whether M2BPGi affects the malignant potential of PC cells in vitro. We also examined the effect of M2BP on PC tumor growth and gemcitabine sensitivity in vivo. Serum M2BPGi levels in PC patients were higher compared with those of healthy subjects. M2BPGi extraction in cancer-associated fibroblasts (CAFs) was higher compared with that of PC cells. M2BPGi treatment promoted the proliferation and invasion of PC cells. The suppression of galectin-3, which binds to M2BPGi, did not affect the proliferation-promoting effect of M2BPGi in PC cells. The suppression of M2BP reduced tumor growth and enhanced gemcitabine sensitivity in PC-bearing xenograft mice. CAF-derived M2BPGi promotes the proliferation and invasion of PC cells. Targeting M2BPGi may represent a new therapeutic strategy to circumvent refractory PC.
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Affiliation(s)
- Takahiro Yamanaka
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | - Kenichiro Araki
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | | | - Ryo Muranushi
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | - Kouki Hoshino
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | - Kei Hagiwara
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | - Dolgormaa Gantumur
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | - Norihiro Ishii
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | - Mariko Tsukagoshi
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | - Akira Watanabe
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | - Norifumi Harimoto
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
| | - Atsushi Masamune
- Division of GastroenterologyTohoku University, Graduate School of MedicineSendaiJapan
| | - Haruki Uojima
- Genome Medical Science Project, National Center for Global Health and MedicineIchikawaJapan
| | - Masashi Mizokami
- Genome Medical Science Project, National Center for Global Health and MedicineIchikawaJapan
| | - Kiyoaki Ito
- Department of GastroenterologyAichi Medical UniversityNagakuteAichiJapan
| | - Ken Shirabe
- Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgical ScienceGunma University, Graduate School of MedicineMaebashiGunmaJapan
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Glitsch MD. Recent advances in acid sensing by G protein coupled receptors. Pflugers Arch 2024; 476:445-455. [PMID: 38340167 PMCID: PMC11006784 DOI: 10.1007/s00424-024-02919-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/30/2024] [Accepted: 01/30/2024] [Indexed: 02/12/2024]
Abstract
Changes in extracellular proton concentrations occur in a variety of tissues over a range of timescales under physiological conditions and also accompany virtually all pathologies, notably cancers, stroke, inflammation and trauma. Proton-activated, G protein coupled receptors are already partially active at physiological extracellular proton concentrations and their activity increases with rising proton concentrations. Their ability to monitor and report changes in extracellular proton concentrations and hence extracellular pH appears to be involved in a variety of processes, and it is likely to mirror and in some cases promote disease progression. Unsurprisingly, therefore, these pH-sensing receptors (pHR) receive increasing attention from researchers working in an expanding range of research areas, from cellular neurophysiology to systemic inflammatory processes. This review is looking at progress made in the field of pHRs over the past few years and also highlights outstanding issues.
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Affiliation(s)
- Maike D Glitsch
- Medical School Hamburg, Am Sandtorkai 1, 20457, Hamburg, Germany.
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Ji R, Chang L, An C, Zhang J. Proton-sensing ion channels, GPCRs and calcium signaling regulated by them: implications for cancer. Front Cell Dev Biol 2024; 12:1326231. [PMID: 38505262 PMCID: PMC10949864 DOI: 10.3389/fcell.2024.1326231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 02/14/2024] [Indexed: 03/21/2024] Open
Abstract
Extracellular acidification of tumors is common. Through proton-sensing ion channels or proton-sensing G protein-coupled receptors (GPCRs), tumor cells sense extracellular acidification to stimulate a variety of intracellular signaling pathways including the calcium signaling, which consequently exerts global impacts on tumor cells. Proton-sensing ion channels, and proton-sensing GPCRs have natural advantages as drug targets of anticancer therapy. However, they and the calcium signaling regulated by them attracted limited attention as potential targets of anticancer drugs. In the present review, we discuss the progress in studies on proton-sensing ion channels, and proton-sensing GPCRs, especially emphasizing the effects of calcium signaling activated by them on the characteristics of tumors, including proliferation, migration, invasion, metastasis, drug resistance, angiogenesis. In addition, we review the drugs targeting proton-sensing channels or GPCRs that are currently in clinical trials, as well as the relevant potential drugs for cancer treatments, and discuss their future prospects. The present review aims to elucidate the important role of proton-sensing ion channels, GPCRs and calcium signaling regulated by them in cancer initiation and development. This review will promote the development of drugs targeting proton-sensing channels or GPCRs for cancer treatments, effectively taking their unique advantage as anti-cancer drug targets.
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Affiliation(s)
- Renhui Ji
- Foundational and Translational Medical Research Center, Department of Allergy and General Surgery, Hohhot First Hospital, Hohhot, China
- Department of Pathophysiology, Basic Medicine College of Inner Mongolia Medical University, Hohhot, China
| | - Li Chang
- Foundational and Translational Medical Research Center, Department of Allergy and General Surgery, Hohhot First Hospital, Hohhot, China
- Department of Pathophysiology, Basic Medicine College of Inner Mongolia Medical University, Hohhot, China
| | - Caiyan An
- Foundational and Translational Medical Research Center, Department of Allergy and General Surgery, Hohhot First Hospital, Hohhot, China
| | - Junjing Zhang
- Foundational and Translational Medical Research Center, Department of Allergy and General Surgery, Hohhot First Hospital, Hohhot, China
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Casarcia N, Rogers P, Guld E, Iyer S, Li Y, Burcher JT, DeLiberto LK, Banerjee S, Bishayee A. Phytochemicals for the prevention and treatment of pancreatic cancer: Current progress and future prospects. Br J Pharmacol 2023. [PMID: 37740585 DOI: 10.1111/bph.16249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 09/06/2023] [Accepted: 09/13/2023] [Indexed: 09/24/2023] Open
Abstract
Pancreatic cancer is the third leading cause of cancer-related deaths in the United States, owing to its aggressive nature and suboptimal treatment options, emphasizing the need for novel therapeutic approaches. Emerging studies have exhibited promising results regarding the therapeutic utility of plant-derived compounds (phytochemicals) in pancreatic cancer. The purpose of this review is to evaluate the potential of phytochemicals in the treatment and prevention of pancreatic cancer. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses was applied to collect articles for this review. Scholarly databases, including PubMed, Scopus and ScienceDirect, were queried for relevant studies using the following keywords: phytochemicals, phenolics, terpenoids, alkaloids, sulfur-containing compounds, in vitro, in vivo, clinical studies, pancreatic cancer, tumour, treatment and prevention. Aggregate results pooled from qualified studies indicate phytochemicals can inhibit pancreatic cancer cell growth or decrease tumour size and volume in animal models. These effects have been attributed to various mechanisms, such as increasing proapoptotic factors, decreasing antiapoptotic factors, or inducing cell death and cell cycle arrest. Notable signalling pathways modulated by phytochemicals include the rat sarcoma/mitogen activated protein kinase, wingless-related integration site/β-catenin and phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signal transduction pathways. Clinically, phytochemicals have been found to increase survival while being well-tolerated and safe, though research is scarce. While these promising results have produced great interest in this field, further in-depth studies are required to characterize the anticancer activities of phytochemicals before they can be utilized to prevent or treat pancreatic cancer in clinical practice.
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Affiliation(s)
- Nicolette Casarcia
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, Florida, USA
| | - Patrick Rogers
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, Florida, USA
| | - Emma Guld
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, Florida, USA
| | - Samvit Iyer
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, Florida, USA
| | - Yutong Li
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, Florida, USA
| | - Jack T Burcher
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, Florida, USA
| | - Lindsay K DeLiberto
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, Florida, USA
| | - Sabyasachi Banerjee
- Department of Pharmaceutical Chemistry, Gupta College of Technological Sciences, Asansol, India
| | - Anupam Bishayee
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, Florida, USA
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Wei S, Wei F, Li M, Yang Y, Zhang J, Li C, Wang J. Target immune components to circumvent sorafenib resistance in hepatocellular carcinoma. Biomed Pharmacother 2023; 163:114798. [PMID: 37121146 DOI: 10.1016/j.biopha.2023.114798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/23/2023] [Accepted: 04/25/2023] [Indexed: 05/02/2023] Open
Abstract
Sorafenib, a multi-kinase inhibitor, has been approved for cancer treatment for decades, especially hepatocellular carcinoma (HCC). Although sorafenib produced substantial clinical benefits in the initial stage, a large proportion of cancer patients acquired drug resistance in subsequent treatment, which always disturbs clinical physicians. Cumulative evidence unraveled the underlying mechanism of sorafenib, but few reports focused on the role of immune subpopulations, since the immunological rationale of sorafenib resistance has not yet been defined. Here, we reviewed the immunoregulatory effects of sorafenib on the tumor microenvironment and emphasized the potential immunological mechanisms of therapeutic resistance to sorafenib. Moreover, we also summarized the clinical outcomes and ongoing trials in combination of sorafenib with immunotherapy, highlighted the immunotherapeutic strategies to improve sorafenib efficacy, and put forward several prospective questions aimed at guiding future research in overcoming sorafenib resistance in HCC.
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Affiliation(s)
- Shuhua Wei
- Department of Radiation Oncology, Peking University Third Hospital, Beijing, PR China
| | - Fenghua Wei
- GMU-GIBH Joint School of Life Sciences, Guangzhou Medical University, Guangzhou City, Guangdong Province, PR China
| | - Mengyuan Li
- Department of Radiation Oncology, Peking University Third Hospital, Beijing, PR China
| | - Yuhan Yang
- Department of Radiation Oncology, Peking University Third Hospital, Beijing, PR China
| | - Jingwen Zhang
- R & D Management Department, China National Biotec Group, Beijing, PR China.
| | - Chunxiao Li
- Department of Radiation Oncology, Peking University Third Hospital, Beijing, PR China.
| | - Junjie Wang
- Department of Radiation Oncology, Peking University Third Hospital, Beijing, PR China.
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Li Y, Li H, He Q, Yang X. Potential of Compounds Originating from the Nature to Act in Hepatocellular Carcinoma Therapy by Targeting the Tumor Immunosuppressive Microenvironment: A Review. Molecules 2022; 28. [PMID: 36615387 DOI: 10.3390/molecules28010195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 12/19/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022]
Abstract
Hepatocellular carcinoma (HCC), the most prevalent subtype of liver cancer, is the second main reason for cancer-related deaths worldwide. In recent decades, sufficient evidence supported that immunotherapy was a safe and effective treatment option for HCC. However, tolerance and frequent recurrence and metastasis occurred in patients after immunotherapy due to the complicated crosstalk in the tumor immunosuppressive microenvironment (TIME) in HCC. Therefore, elucidating the TIME in HCC and finding novel modulators to target TIME for attenuating immune suppression is critical to optimize immunotherapy. Recently, studies have shown the potentially immunoregulatory activities of natural compounds, characterized by multiple targets and pathways and low toxicity. In this review, we concluded the unique role of TIME in HCC. Moreover, we summarized evidence that supports the hypothesis of natural compounds to target TIME to improve immunotherapy. Furthermore, we discussed the comprehensive mechanisms of these natural compounds in the immunotherapy of HCC. Accordingly, we present a well-grounded review of the naturally occurring compounds in cancer immunotherapy, expecting to shed new light on discovering novel anti-HCC immunomodulatory drugs from natural sources.
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Chiu K, Chiou HC, Huang C, Lu P, Kuo H, Wang J, Lin M. Natural Compounds Targeting Cancer-Associated Fibroblasts against Digestive System Tumor Progression: Therapeutic Insights. Biomedicines 2022; 10:713. [PMID: 35327514 PMCID: PMC8945097 DOI: 10.3390/biomedicines10030713] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 03/16/2022] [Accepted: 03/18/2022] [Indexed: 01/27/2023] Open
Abstract
Cancer-associated fibroblasts (CAFs) are critical for cancer occurrence and progression in the tumor microenvironment (TME), due to their versatile roles in extracellular matrix remodeling, tumor–stroma crosstalk, immunomodulation, and angiogenesis. CAFs are the most abundant stromal component in the TME and undergo epigenetic modification and abnormal signaling cascade activation, such as transforming growth factor-β (TGF-β) and Wnt pathways that maintain the distinct phenotype of CAFs, which differs from normal fibroblasts. CAFs have been considered therapeutic targets due to their putative oncogenic functions. Current digestive system cancer treatment strategies often result in lower survival outcomes and fail to prevent cancer progression; therefore, comprehensive characterization of the tumor-promoting and -restraining CAF activities might facilitate the design of new therapeutic approaches. In this review, we summarize the enormous literature on natural compounds that mediate the crosstalk of CAFs with digestive system cancer cells, discuss how the biology and the multifaceted functions of CAFs contribute to cancer progression, and finally, pave the way for CAF-related antitumor therapies.
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Hao X, Sun G, Zhang Y, Kong X, Rong D, Song J, Tang W, Wang X. Targeting Immune Cells in the Tumor Microenvironment of HCC: New Opportunities and Challenges. Front Cell Dev Biol 2021; 9:775462. [PMID: 34869376 PMCID: PMC8633569 DOI: 10.3389/fcell.2021.775462] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 10/19/2021] [Indexed: 12/17/2022] Open
Abstract
Immune associated cells in the microenvironment have a significant impact on the development and progression of hepatocellular carcinoma (HCC) and have received more and more attention. Different types of immune-associated cells play different roles, including promoting/inhibiting HCC and several different types that are controversial. It is well known that immune escape of HCC has become a difficult problem in tumor therapy. Therefore, in recent years, a large number of studies have focused on the immune microenvironment of HCC, explored many mechanisms worth identifying tumor immunosuppression, and developed a variety of immunotherapy methods as targets, laying the foundation for the final victory in the fight against HCC. This paper reviews recent studies on the immune microenvironment of HCC that are more reliable and important, and provides a more comprehensive view of the investigation of the immune microenvironment of HCC and the development of more immunotherapeutic approaches based on the relevant summaries of different immune cells.
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Affiliation(s)
- Xiaopei Hao
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, NHC Key Laboratory of Living Donor Liver Transplantation, Nanjing Medical University, Nanjing, China
| | - Guangshun Sun
- Department of General Surgery, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Yao Zhang
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, NHC Key Laboratory of Living Donor Liver Transplantation, Nanjing Medical University, Nanjing, China
| | - Xiangyi Kong
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, NHC Key Laboratory of Living Donor Liver Transplantation, Nanjing Medical University, Nanjing, China
| | - Dawei Rong
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, NHC Key Laboratory of Living Donor Liver Transplantation, Nanjing Medical University, Nanjing, China
| | - Jinhua Song
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, NHC Key Laboratory of Living Donor Liver Transplantation, Nanjing Medical University, Nanjing, China
| | - Weiwei Tang
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, NHC Key Laboratory of Living Donor Liver Transplantation, Nanjing Medical University, Nanjing, China
| | - Xuehao Wang
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, NHC Key Laboratory of Living Donor Liver Transplantation, Nanjing Medical University, Nanjing, China
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Jia W, Liang S, Cheng B, Ling C. The Role of Cancer-Associated Fibroblasts in Hepatocellular Carcinoma and the Value of Traditional Chinese Medicine Treatment. Front Oncol 2021; 11:763519. [PMID: 34868982 PMCID: PMC8636329 DOI: 10.3389/fonc.2021.763519] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 10/28/2021] [Indexed: 01/10/2023] Open
Abstract
Invasion and metastasis are the main reasons for the high mortality of liver cancer, which involve the interaction of tumor stromal cells and malignant cells. Cancer-associated fibroblasts (CAFs) are one of the major constituents of tumor stromal cells affecting tumor growth, invasion, and metastasis. The heterogeneous properties and sources of CAFs make both tumor-supporting and tumor-suppression effects possible. The mechanisms for CAFs in supporting hepatocellular carcinoma (HCC) progression can be categorized into upregulated aggressiveness and stemness, transformed metabolism toward glycolysis and glutamine reductive carboxylation, polarized tumor immunity toward immune escape of HCC cells, and increased angiogenesis. The tumor-suppressive effect of fibroblasts highlights the functional heterogenicity of CAF populations and provides new insights into tumor–stromal interplay mechanisms. In this review, we introduced several key inflammatory signaling pathways in the transformation of CAFs from normal stromal cells and the heterogeneous biofunctions of activated CAFs. In view of the pleiotropic regulation properties of traditional Chinese medicine (TCM) and heterogeneous effects of CAFs, we also introduced the application and values of TCM in the treatment of HCC through targeting CAFs.
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Affiliation(s)
- Wentao Jia
- School of Traditional Chinese Medicine, Naval Medical University, Shanghai, China
| | - Shufang Liang
- Department of Traditional Chinese Medicine, Changhai Hospital, Navy Medical University, Shanghai, China
| | - Binbin Cheng
- School of Traditional Chinese Medicine, Naval Medical University, Shanghai, China
| | - Changquan Ling
- School of Traditional Chinese Medicine, Naval Medical University, Shanghai, China
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Abstract
The group of proton-sensing G-protein coupled receptors (GPCRs) consists of the four receptors GPR4, TDAG8 (GPR65), OGR1 (GPR68), and G2A (GPR132). These receptors are cellular sensors of acidification, a property that has been attributed to the presence of crucial histidine residues. However, the pH detection varies considerably among the group of proton-sensing GPCRs and ranges from pH of 5.5 to 7.8. While the proton-sensing GPCRs were initially considered to detect acidic cellular environments in the context of inflammation, recent observations have expanded our knowledge about their physiological and pathophysiological functions and many additional individual and unique features have been discovered that suggest a more differentiated role of these receptors in health and disease. It is known that all four receptors contribute to different aspects of tumor biology, cardiovascular physiology, and asthma. However, apart from their overlapping functions, they seem to have individual properties, and recent publications identify potential roles of individual GPCRs in mechanosensation, intestinal inflammation, oncoimmunological interactions, hematopoiesis, as well as inflammatory and neuropathic pain. Here, we put together the knowledge about the biological functions and structural features of the four proton-sensing GPCRs and discuss the biological role of each of the four receptors individually. We explore all currently known pharmacological modulators of the four receptors and highlight potential use. Finally, we point out knowledge gaps in the biological and pharmacological context of proton-sensing GPCRs that should be addressed by future studies.
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Affiliation(s)
- Marco Sisignano
- Institute of Clinical Pharmacology, Pharmazentrum Frankfurt/ZAFES, University Hospital of Goethe-University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany;
- Fraunhofer Institute for Translational Medicine and Pharmacology (ITMP), Theodor-Stern-Kai 7, 60596 Frankfurt am Main, Germany
- Correspondence:
| | - Michael J. M. Fischer
- Center for Physiology and Pharmacology, Institute of Physiology, Medical University of Vienna, Schwarzspanierstrasse 17, 1090 Vienna, Austria;
| | - Gerd Geisslinger
- Institute of Clinical Pharmacology, Pharmazentrum Frankfurt/ZAFES, University Hospital of Goethe-University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany;
- Fraunhofer Institute for Translational Medicine and Pharmacology (ITMP), Theodor-Stern-Kai 7, 60596 Frankfurt am Main, Germany
- Fraunhofer Cluster of Excellence for Immune-Mediated Diseases (CIMD), Theodor-Stern-Kai 7, 60596 Frankfurt am Main, Germany
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