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Li X, Lakshmi SP, Uemasu K, Lane Z, Reddy RT, Chandra D, Zou C, Jiang Y, Nyunoya T. FBXL19 Targeted STK11 Degradation Enhances Cigarette Smoke-Induced Airway Epithelial Cell Cytotoxicity. COPD 2024; 21:2342797. [PMID: 38712759 PMCID: PMC11186665 DOI: 10.1080/15412555.2024.2342797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 04/09/2024] [Indexed: 05/08/2024]
Abstract
Objective: To investigate the effects of cigarette smoke (CS) on Serine/Threonine Kinase 11 (STK11) and to determine STK11's role in CS-induced airway epithelial cell cytotoxicity.Methods: STK11 expression levels in the lung tissues of smokers with or without COPD and mice exposed to CS or room air (RA) were determined by immunoblotting and RT-PCR. BEAS-2Bs-human bronchial airway epithelial cells were exposed to CS extract (CSE), and the changes in STK11 expression levels were determined by immunoblotting and RT-PCR. BEAS-2B cells were transfected with STK11-specific siRNA or STK11 expression plasmid, and the effects of CSE on airway epithelial cell cytotoxicity were measured. To determine the specific STK11 degradation-proteolytic pathway, BEAS-2Bs were treated with cycloheximide alone or combined with MG132 or leupeptin. Finally, to identify the F-box protein mediating the STK11 degradation, a screening assay was performed using transfection with a panel of FBXL E3 ligase subunits.Results: STK11 protein levels were significantly decreased in the lung tissues of smokers with COPD relative to smokers without COPD. STK11 protein levels were also significantly decreased in mouse lung tissues exposed to CS compared to RA. Exposure to CSE shortened the STK11 mRNA and protein half-life to 4 h in BEAS-2B cells. STK11 protein overexpression attenuated the CSE-induced cytotoxicity; in contrast, its knockdown augmented CSE-induced cytotoxicity. FBXL19 mediates CSE-induced STK11 protein degradation via the ubiquitin-proteasome pathway in cultured BEAS-2B cells. FBXL19 overexpression led to accelerated STK11 ubiquitination and degradation in a dose-dependent manner.Conclusions: Our results suggest that CSE enhances the degradation of STK11 protein in airway epithelial cells via the FBXL19-mediated ubiquitin-proteasomal pathway, leading to augmented cell death.HIGHLIGHTSLung tissues of COPD-smokers exhibited a decreased STK11 RNA and protein expression.STK11 overexpression attenuates CS-induced airway epithelial cell cytotoxicity.STK11 depletion augments CS-induced airway epithelial cell cytotoxicity.CS diminishes STK11 via FBXL19-mediated ubiquitin-proteasome degradation.
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Affiliation(s)
- Xiuying Li
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- Medical Specialty Service Line, Veterans Affairs Pittsburgh Healthcare System, Pittsburg, PA 15240, USA
| | - Sowmya P. Lakshmi
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- Medical Specialty Service Line, Veterans Affairs Pittsburgh Healthcare System, Pittsburg, PA 15240, USA
| | - Kiyoshi Uemasu
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Zachary Lane
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- Medical Specialty Service Line, Veterans Affairs Pittsburgh Healthcare System, Pittsburg, PA 15240, USA
| | - Rajan T. Reddy
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Divay Chandra
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Chunbin Zou
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- Medical Specialty Service Line, Veterans Affairs Pittsburgh Healthcare System, Pittsburg, PA 15240, USA
| | - Yu Jiang
- Department of Pharmacology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Toru Nyunoya
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- Medical Specialty Service Line, Veterans Affairs Pittsburgh Healthcare System, Pittsburg, PA 15240, USA
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Teuwen JTJ, van der Vorst EPC, Maas SL. Navigating the Maze of Kinases: CaMK-like Family Protein Kinases and Their Role in Atherosclerosis. Int J Mol Sci 2024; 25:6213. [PMID: 38892400 PMCID: PMC11172518 DOI: 10.3390/ijms25116213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2024] [Revised: 05/30/2024] [Accepted: 06/02/2024] [Indexed: 06/21/2024] Open
Abstract
Circulating low-density lipoprotein (LDL) levels are a major risk factor for cardiovascular diseases (CVD), and even though current treatment strategies focusing on lowering lipid levels are effective, CVD remains the primary cause of death worldwide. Atherosclerosis is the major cause of CVD and is a chronic inflammatory condition in which various cell types and protein kinases play a crucial role. However, the underlying mechanisms of atherosclerosis are not entirely understood yet. Notably, protein kinases are highly druggable targets and represent, therefore, a novel way to target atherosclerosis. In this review, the potential role of the calcium/calmodulin-dependent protein kinase-like (CaMKL) family and its role in atherosclerosis will be discussed. This family consists of 12 subfamilies, among which are the well-described and conserved liver kinase B1 (LKB1) and 5' adenosine monophosphate-activated protein kinase (AMPK) subfamilies. Interestingly, LKB1 plays a key role and is considered a master kinase within the CaMKL family. It has been shown that LKB1 signaling leads to atheroprotective effects, while, for example, members of the microtubule affinity-regulating kinase (MARK) subfamily have been described to aggravate atherosclerosis development. These observations highlight the importance of studying kinases and their signaling pathways in atherosclerosis, bringing us a step closer to unraveling the underlying mechanisms of atherosclerosis.
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Affiliation(s)
- Jules T. J. Teuwen
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, 52074 Aachen, Germany;
- Aachen-Maastricht Institute for CardioRenal Disease (AMICARE), RWTH Aachen University, 52074 Aachen, Germany
| | - Emiel P. C. van der Vorst
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, 52074 Aachen, Germany;
- Aachen-Maastricht Institute for CardioRenal Disease (AMICARE), RWTH Aachen University, 52074 Aachen, Germany
- Interdisciplinary Center for Clinical Research (IZKF), RWTH Aachen University, 52074 Aachen, Germany
- Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Sanne L. Maas
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, 52074 Aachen, Germany;
- Aachen-Maastricht Institute for CardioRenal Disease (AMICARE), RWTH Aachen University, 52074 Aachen, Germany
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Cai Z, Jiang Y, Tong H, Liang M, Huang Y, Fang L, Liang F, Hu Y, Shi X, Wang J, Wang Z, Ji Q, Huo H, Shen L, He B. Cellular and molecular characteristics of stromal Lkb1 deficiency-induced gastrointestinal polyposis based on single-cell RNA sequencing. J Pathol 2024; 263:47-60. [PMID: 38389501 DOI: 10.1002/path.6259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 10/17/2023] [Accepted: 01/04/2024] [Indexed: 02/24/2024]
Abstract
Liver kinase B1 (Lkb1), encoded by serine/threonine kinase (Stk11), is a serine/threonine kinase and tumor suppressor that is strongly implicated in Peutz-Jeghers syndrome (PJS). Numerous studies have shown that mesenchymal-specific Lkb1 is sufficient for the development of PJS-like polyps in mice. However, the cellular origin and components of these Lkb1-associated polyps and underlying mechanisms remain elusive. In this study, we generated tamoxifen-inducible Lkb1flox/flox;Myh11-Cre/ERT2 and Lkb1flox/flox;PDGFRα-Cre/ERT2 mice, performed single-cell RNA sequencing (scRNA-seq) and imaging-based lineage tracing, and aimed to investigate the cellular complexity of gastrointestinal polyps associated with PJS. We found that Lkb1flox/+;Myh11-Cre/ERT2 mice developed gastrointestinal polyps starting at 9 months after tamoxifen treatment. scRNA-seq revealed aberrant stem cell-like characteristics of epithelial cells from polyp tissues of Lkb1flox/+;Myh11-Cre/ERT2 mice. The Lkb1-associated polyps were further characterized by a branching smooth muscle core, abundant extracellular matrix deposition, and high immune cell infiltration. In addition, the Spp1-Cd44 or Spp1-Itga8/Itgb1 axes were identified as important interactions among epithelial, mesenchymal, and immune compartments in Lkb1-associated polyps. These characteristics of gastrointestinal polyps were also demonstrated in another mouse model, tamoxifen-inducible Lkb1flox/flox;PDGFRα-Cre/ERT2 mice, which developed obvious gastrointestinal polyps as early as 2-3 months after tamoxifen treatment. Our findings further confirm the critical role of mesenchymal Lkb1/Stk11 in gastrointestinal polyposis and provide novel insight into the cellular complexity of Lkb1-associated polyp biology. © 2024 The Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Zhaohua Cai
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Yangjing Jiang
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Huan Tong
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Min Liang
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Yijie Huang
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Liang Fang
- Department of Cardiac Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Feng Liang
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Yunwen Hu
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Xin Shi
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Jian Wang
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Zi Wang
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Qingqi Ji
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Huanhuan Huo
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Linghong Shen
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Ben He
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
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Chen K, Deng Z, Zhu C, Zhang Q, Chen R, Li T, Luo J, Zhou Z, Zeng R, Zhang T, Zeng Z. LKB1 delays atherosclerosis by inhibiting phenotypic transformation of vascular smooth muscle cells. Int J Cardiol 2024; 394:131363. [PMID: 37722454 DOI: 10.1016/j.ijcard.2023.131363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 07/01/2023] [Accepted: 09/15/2023] [Indexed: 09/20/2023]
Abstract
BACKGROUND AND OBJECTIVE Although liver kinase B1 (LKB1) is a well-known tumor suppressor gene, and its encoded protein has important biological functions, it is not clear whether LKB1 can inhibit atherosclerosis by regulating vascular smooth muscle cells (VSMCs). The purpose of this study is to explore the relationship among LKB1, VSMCs and atherosclerosis. METHODS AND RESULTS ApoE-/- mice with VSMCs-specific overexpression of LKB1 were constructed by adeno-associated virus transfection technique, and then fed with high-fat diet for eight weeks. The effect of LKB1 overexpression on atherosclerosis in mice was investigated by oil red O staining, HE staining, immunofluorescence and Western Blot. The results showed that the expression of LKB1 mRNA and protein in arterial tissue of mice increased significantly after overexpression of LKB1. The degree of atherosclerosis, smooth muscle fiber proliferation and lipid accumulation were significantly alleviated in the overexpression group. The results of Western Blot showed that the expression of α-SMA was increased, while the expression of OPN and CD68 was significantly decreased in the overexpression group (P < 0.05). The Immunofluorescence results of Image Pro Plus software analysis showed that the co-localization relationship between α-SMA and CD68 was more obvious in the control group (P < 0.01). CONCLUSION Our results suggested that LKB1 can delay the progression of atherosclerosis by inhibiting the phenotypic transition of VSMCs.
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Affiliation(s)
- Kaicong Chen
- Cardiovascular Department, The Sixth Affiliated Hospital, School of Medicine, South China University of Technology, Foshan 528200, Guangdong Province, China.
| | - Zhiwen Deng
- Cardiovascular Department, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, Guangdong Province, China
| | - Chunyan Zhu
- Cardiovascular Department, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, Guangdong Province, China
| | - Qing Zhang
- Cardiovascular Department, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, Guangdong Province, China
| | - Rong Chen
- Cardiovascular Department, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, Guangdong Province, China
| | - Tudi Li
- Cardiovascular Department, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, Guangdong Province, China
| | - Junqian Luo
- Cardiovascular Department, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, Guangdong Province, China
| | - Zihao Zhou
- Cardiovascular Department, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, Guangdong Province, China
| | - Rui Zeng
- Monash University, Victoria 3800, Australia.
| | - Tong Zhang
- Cardiovascular Department, The Sixth Affiliated Hospital, School of Medicine, South China University of Technology, Foshan 528200, Guangdong Province, China.
| | - Zhihuan Zeng
- Cardiovascular Department, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, Guangdong Province, China.
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Fang KT, Hung H, Lau NYS, Chi JH, Wu DC, Cheng KH. Development of a Genetically Engineered Mouse Model Recapitulating LKB1 and PTEN Deficiency in Gastric Cancer Pathogenesis. Cancers (Basel) 2023; 15:5893. [PMID: 38136437 PMCID: PMC10741874 DOI: 10.3390/cancers15245893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/12/2023] [Accepted: 12/15/2023] [Indexed: 12/24/2023] Open
Abstract
The LKB1 and PTEN genes are critical in gastric cancer (G.C.) development. LKB1, a robust tumor suppressor gene, encodes a serine/threonine kinase that directly triggers the activation of AMPK-an integral cellular metabolic kinase. The role of the LKB1 pathway extends to maintaining the stability of epithelial junctions by regulating E-cadherin expression. Conversely, PTEN, a frequently mutated tumor suppressor gene in various human cancers, emerges as a pivotal negative regulator of the phosphoinositide 3-kinase (PI3K) signaling pathway. This study is set to leverage the H+/K+ ATPase Cre transgene strain to precisely target Cre recombinase expression at parietal cells within the stomach. This strategic maneuver seeks to selectively nullify the functions of both LKB1 and PTEN in a manner specific to the stomach, thereby instigating the development of G.C. in a fashion akin to human gastric adenocarcinoma. Moreover, this study endeavors to dissect the intricate ways in which these alterations contribute to the histopathologic advancement of gastric tumors, their potential for invasiveness and metastasis, their angiogenesis, and the evolving tumor stromal microenvironment. Our results show that conditional deletion of PTEN and LKB1 provides an ideal cancer microenvironment for G.C. tumorigenesis by promoting cancer cell proliferation, angiogenesis, and metastasis.
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Affiliation(s)
- Kuan-Te Fang
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan; (K.-T.F.); (H.H.); (N.Y.S.L.); (J.-H.C.)
| | - Hsin Hung
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan; (K.-T.F.); (H.H.); (N.Y.S.L.); (J.-H.C.)
| | - Nga Yin Sadonna Lau
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan; (K.-T.F.); (H.H.); (N.Y.S.L.); (J.-H.C.)
- Center of Excellence for Metabolic Associated Fatty Liver Disease, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan
| | - Jou-Hsi Chi
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan; (K.-T.F.); (H.H.); (N.Y.S.L.); (J.-H.C.)
- Center of Excellence for Metabolic Associated Fatty Liver Disease, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan
| | - Deng-Chyang Wu
- Division of Gastroenterology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Kuang-Hung Cheng
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan; (K.-T.F.); (H.H.); (N.Y.S.L.); (J.-H.C.)
- Center of Excellence for Metabolic Associated Fatty Liver Disease, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan
- Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- National Institute of Cancer Research, National Health Research Institutes, Tainan 70456, Taiwan
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Xu Z, Gu G. Cancer Risk of Peutz-Jeghers Syndrome and Treatment Experience: A Chinese Medical Center. Clin Colon Rectal Surg 2023; 36:406-414. [PMID: 37795464 PMCID: PMC10547534 DOI: 10.1055/s-0043-1767704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/06/2023]
Abstract
Peutz-Jeghers syndrome (PJS), also known as hereditary mucocutaneous pigmented gastrointestinal polyposis, is a clinically rare autosomal dominant genetic disease, which falls into the category of hereditary colorectal cancer. There are ∼7,000 new cases of PJS in China every year, and 170,000 PJS patients may survive for a long time in society. PJS polyps are characterized by an early age of onset, difficult diagnosis and treatment, and easy recurrence. With repeated growth, polyps can lead to serious complications such as intestinal obstruction, intussusception, gastrointestinal bleeding, and cancerization, which cause serious clinical problems. Due to repeated hospitalization and endoscopic follow-up, PJS patients and their families suffer from great physical and mental pain and economic burden. With the in-depth understanding of PJS and the development and popularization of endoscopic techniques in the past decade, an integrated treatment modality based on endoscopy plus surgery has gradually become the preferred treatment in most hospitals, which greatly improves the quality of life of PJS patients. However, there is still a lack of effective drug prevention and cure means. In this paper, the current clinical treatment means for PJS polyps were summarized by literature review combined with the treatment experience of our medical center, with a focus on their clinical diagnosis, treatment, and cancer risk.
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Affiliation(s)
- Zuxin Xu
- Fifth Clinical College of Anhui Medical University, Air Force Clinical College of Anhui Medical University, Beijing, China
- Department of General Surgery, Air Force Medical Center, Beijing, China
| | - Guoli Gu
- Department of General Surgery, Air Force Medical Center, Beijing, China
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Deng Q, Li H, Yue X, Guo C, Sun Y, Ma C, Gao J, Wu Y, Du B, Yang J, Zhang C, Zhang W. Smooth muscle liver kinase B1 inhibits foam cell formation and atherosclerosis via direct phosphorylation and activation of SIRT6. Cell Death Dis 2023; 14:542. [PMID: 37607939 PMCID: PMC10444762 DOI: 10.1038/s41419-023-06054-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 08/01/2023] [Accepted: 08/08/2023] [Indexed: 08/24/2023]
Abstract
Foam cell formation is a hallmark of the early phase of atherosclerosis. Growing evidence has demonstrated that vascular smooth muscle cells (VSMCs) comprise a considerable proportion of foam cells. Liver kinase B1 (LKB1) plays a crucial part in cardiovascular diseases. However, the role of LKB1 in VSMC-derived foam cell formation and atherosclerosis remains unclear. To explore the effects of LKB1 on VSMC-derived foam cell formation and atherosclerosis, we generated smooth muscle-specific LKB1 knockout (LKB1SMKO) mice by crossbreeding LKB1flox/flox mice with SM22α-CreERT2 mice. LKB1 expression decreased in plaque-loaded aortas and oxidized low-density lipoprotein (oxLDL)-treated VSMCs. Compared with controls, atherosclerosis development was exacerbated in LKB1SMKO mice via the promotion of VSMC-derived foam cell formation. Conversely, LKB1 overexpression inhibited lipid uptake and foam cell formation in VSMCs. Mechanistically, LKB1 binds to SIRT6 and directly phosphorylates and activates it, thereby reducing lectin-like oxLDL receptor-1 (LOX-1) via SIRT6-dependent histone deacetylation. Finally, adeno-associated virus (AAV)-mediated LOX-1 deficiency in smooth muscle ameliorated atherosclerosis in LKB1SMKO mice. Our findings suggest that LKB1 may modulate VSMC-derived foam cell formation and atherosclerosis via the phosphorylation and activation of SIRT6.
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Affiliation(s)
- Qiming Deng
- National Key Laboratory for Innovation and Transformation of Luobing Theory; The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences; Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China
| | - Hongxuan Li
- National Key Laboratory for Innovation and Transformation of Luobing Theory; The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences; Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China.
| | - Xiaolin Yue
- National Key Laboratory for Innovation and Transformation of Luobing Theory; The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences; Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China
| | - Chenghu Guo
- National Key Laboratory for Innovation and Transformation of Luobing Theory; The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences; Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China
| | - Yuanyuan Sun
- National Key Laboratory for Innovation and Transformation of Luobing Theory; The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences; Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China
| | - Chang Ma
- National Key Laboratory for Innovation and Transformation of Luobing Theory; The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences; Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China
| | - Jiangang Gao
- School of Life Science and Key Laboratory of the Ministry of Education for Experimental Teratology, Shandong University, Jinan, China
| | - Yue Wu
- Department of Cardiology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Bin Du
- Department of Cardiology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Jianmin Yang
- National Key Laboratory for Innovation and Transformation of Luobing Theory; The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences; Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China
| | - Cheng Zhang
- National Key Laboratory for Innovation and Transformation of Luobing Theory; The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences; Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China.
| | - Wencheng Zhang
- National Key Laboratory for Innovation and Transformation of Luobing Theory; The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences; Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China.
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Otegui N, Houry M, Arozarena I, Serrano D, Redin E, Exposito F, Leon S, Valencia K, Montuenga L, Calvo A. Cancer Cell-Intrinsic Alterations Associated with an Immunosuppressive Tumor Microenvironment and Resistance to Immunotherapy in Lung Cancer. Cancers (Basel) 2023; 15:3076. [PMID: 37370686 PMCID: PMC10295869 DOI: 10.3390/cancers15123076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 05/24/2023] [Accepted: 06/01/2023] [Indexed: 06/29/2023] Open
Abstract
Despite the great clinical success of immunotherapy in lung cancer patients, only a small percentage of them (<40%) will benefit from this therapy alone or combined with other strategies. Cancer cell-intrinsic and cell-extrinsic mechanisms have been associated with a lack of response to immunotherapy. The present study is focused on cancer cell-intrinsic genetic, epigenetic, transcriptomic and metabolic alterations that reshape the tumor microenvironment (TME) and determine response or refractoriness to immune checkpoint inhibitors (ICIs). Mutations in KRAS, SKT11(LKB1), KEAP1 and TP53 and co-mutations of these genes are the main determinants of ICI response in non-small-cell lung cancer (NSCLC) patients. Recent insights into metabolic changes in cancer cells that impose restrictions on cytotoxic T cells and the efficacy of ICIs indicate that targeting such metabolic restrictions may favor therapeutic responses. Other emerging pathways for therapeutic interventions include epigenetic modulators and DNA damage repair (DDR) pathways, especially in small-cell lung cancer (SCLC). Therefore, the many potential pathways for enhancing the effect of ICIs suggest that, in a few years, we will have much more personalized medicine for lung cancer patients treated with immunotherapy. Such strategies could include vaccines and chimeric antigen receptor (CAR) cells.
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Affiliation(s)
- Nerea Otegui
- CCUN Cancer Center and Program in Solid Tumors, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain; (N.O.); (M.H.); (D.S.); (S.L.); (K.V.); (L.M.)
- Department of Pathology, Anatomy and Physiology, School of Medicine, University of Navarra, 31008 Pamplona, Spain
| | - Maeva Houry
- CCUN Cancer Center and Program in Solid Tumors, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain; (N.O.); (M.H.); (D.S.); (S.L.); (K.V.); (L.M.)
- Department of Pathology, Anatomy and Physiology, School of Medicine, University of Navarra, 31008 Pamplona, Spain
| | - Imanol Arozarena
- Instituto de Investigación Sanitaria de Navarra (IDISNA), 31008 Pamplona, Spain;
- Cancer Signaling Unit, Navarrabiomed, University Hospital of Navarra (HUN), Public University of Navarra (UPNA), 31008 Pamplona, Spain
| | - Diego Serrano
- CCUN Cancer Center and Program in Solid Tumors, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain; (N.O.); (M.H.); (D.S.); (S.L.); (K.V.); (L.M.)
- Department of Pathology, Anatomy and Physiology, School of Medicine, University of Navarra, 31008 Pamplona, Spain
| | - Esther Redin
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA;
| | - Francisco Exposito
- Yale Cancer Center, New Haven, CT 06519, USA;
- Department of Pathology, Yale School of Medicine, New Haven, CT 06510, USA
| | - Sergio Leon
- CCUN Cancer Center and Program in Solid Tumors, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain; (N.O.); (M.H.); (D.S.); (S.L.); (K.V.); (L.M.)
- Department of Pathology, Anatomy and Physiology, School of Medicine, University of Navarra, 31008 Pamplona, Spain
| | - Karmele Valencia
- CCUN Cancer Center and Program in Solid Tumors, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain; (N.O.); (M.H.); (D.S.); (S.L.); (K.V.); (L.M.)
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), ISCIII, 28029 Madrid, Spain
| | - Luis Montuenga
- CCUN Cancer Center and Program in Solid Tumors, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain; (N.O.); (M.H.); (D.S.); (S.L.); (K.V.); (L.M.)
- Department of Pathology, Anatomy and Physiology, School of Medicine, University of Navarra, 31008 Pamplona, Spain
- Instituto de Investigación Sanitaria de Navarra (IDISNA), 31008 Pamplona, Spain;
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), ISCIII, 28029 Madrid, Spain
| | - Alfonso Calvo
- CCUN Cancer Center and Program in Solid Tumors, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain; (N.O.); (M.H.); (D.S.); (S.L.); (K.V.); (L.M.)
- Department of Pathology, Anatomy and Physiology, School of Medicine, University of Navarra, 31008 Pamplona, Spain
- Instituto de Investigación Sanitaria de Navarra (IDISNA), 31008 Pamplona, Spain;
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), ISCIII, 28029 Madrid, Spain
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9
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Compton SE, Kitchen-Goosen SM, DeCamp LM, Lau KH, Mabvakure B, Vos M, Williams KS, Wong KK, Shi X, Rothbart SB, Krawczyk CM, Jones RG. LKB1 controls inflammatory potential through CRTC2-dependent histone acetylation. Mol Cell 2023:S1097-2765(23)00288-5. [PMID: 37172591 DOI: 10.1016/j.molcel.2023.04.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 03/17/2023] [Accepted: 04/18/2023] [Indexed: 05/15/2023]
Abstract
Deregulated inflammation is a critical feature driving the progression of tumors harboring mutations in the liver kinase B1 (LKB1), yet the mechanisms linking LKB1 mutations to deregulated inflammation remain undefined. Here, we identify deregulated signaling by CREB-regulated transcription coactivator 2 (CRTC2) as an epigenetic driver of inflammatory potential downstream of LKB1 loss. We demonstrate that LKB1 mutations sensitize both transformed and non-transformed cells to diverse inflammatory stimuli, promoting heightened cytokine and chemokine production. LKB1 loss triggers elevated CRTC2-CREB signaling downstream of the salt-inducible kinases (SIKs), increasing inflammatory gene expression in LKB1-deficient cells. Mechanistically, CRTC2 cooperates with the histone acetyltransferases CBP/p300 to deposit histone acetylation marks associated with active transcription (i.e., H3K27ac) at inflammatory gene loci, promoting cytokine expression. Together, our data reveal a previously undefined anti-inflammatory program, regulated by LKB1 and reinforced through CRTC2-dependent histone modification signaling, that links metabolic and epigenetic states to cell-intrinsic inflammatory potential.
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Affiliation(s)
- Shelby E Compton
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
| | - Susan M Kitchen-Goosen
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA; Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Lisa M DeCamp
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA; Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Kin H Lau
- Bioinformatics and Biostatistics Core, Van Andel Institute, Grand Rapids, MI, USA
| | - Batsirai Mabvakure
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
| | - Matthew Vos
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA; Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Kelsey S Williams
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA; Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Kwok-Kin Wong
- Laura and Isaac Perlmutter Cancer Center, NYU Langone Health, New York, NY, USA
| | - Xiaobing Shi
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI, USA
| | - Scott B Rothbart
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI, USA
| | - Connie M Krawczyk
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA; Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Russell G Jones
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA; Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA.
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10
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Huang E, Li S. Liver Kinase B1 Functions as a Regulator for Neural Development and a Therapeutic Target for Neural Repair. Cells 2022; 11:cells11182861. [PMID: 36139438 PMCID: PMC9496952 DOI: 10.3390/cells11182861] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/02/2022] [Accepted: 09/10/2022] [Indexed: 11/16/2022] Open
Abstract
The liver kinase B1 (LKB1), also known as serine/threonine kinase 11 (STK11) and Par-4 in C. elegans, has been identified as a master kinase of AMPKs and AMPK-related kinases. LKB1 plays a crucial role in cell growth, metabolism, polarity, and tumor suppression. By interacting with the downstream signals of SAD, NUAK, MARK, and other kinases, LKB1 is critical to regulating neuronal polarization and axon branching during development. It also regulates Schwann cell function and the myelination of peripheral axons. Regulating LKB1 activity has become an attractive strategy for repairing an injured nervous system. LKB1 upregulation enhances the regenerative capacity of adult CNS neurons and the recovery of locomotor function in adult rodents with CNS axon injury. Here, we update the major cellular and molecular mechanisms of LKB1 in regulating neuronal polarization and neural development, and the implications thereof for promoting neural repair, axon regeneration, and functional recovery in adult mammals.
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11
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Farooq H, Bien H, Chang V, Becker D, Park YH, Bates S. Loss of function STK11 alterations and poor outcomes in non-small-cell lung cancer: Literature and case series of US Veterans. Semin Oncol 2022; 49:S0093-7754(22)00048-3. [PMID: 35831213 DOI: 10.1053/j.seminoncol.2022.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 06/13/2022] [Accepted: 06/14/2022] [Indexed: 11/11/2022]
Abstract
Emerging evidence suggests that STK11 alterations, frequently found in non-small-cell lung cancers, may be prognostic and/or predictive of response to therapy, particularly immunotherapy. STK11 affects multiple important cellular pathways, and mutations lead to tumor growth by creating an immunosuppressive and altered metabolic environment through changes in AMPK, STING, and vascular endothelial growth factor pathways. We illustrate the questions surrounding STK11 genomic alteration in NSCLC with a case series comprising six United States Veterans from a single institution. We discuss the history of STK11, review studies on its clinical impact, and describe putative mechanisms of how loss of STK11 might engender resistance to immunotherapy or other therapies. While the exact impact of STK11 alteration in non-small-cell lung cancer remain to be fully elucidated, future research and ongoing clinical trials will help us better understand its role in cancer development and devise more effective treatment strategies.
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Affiliation(s)
- Hafsa Farooq
- Section of Hematology and Oncology, VA Northport Medical Center, Northport, NY; Division of Hematology and Oncology, Renaissance School of Medicine, Stony Brook, NY.
| | - Harold Bien
- Section of Hematology and Oncology, VA Northport Medical Center, Northport, NY; Division of Hematology and Oncology, Renaissance School of Medicine, Stony Brook, NY
| | - Victor Chang
- Section of Hematology Oncology, VA New Jersey Health Care System, East Orange, NJ; Division of Hematology/Oncology, Department of Medicine, Rutgers New Jersey Medical School, Newark, NJ
| | - Daniel Becker
- Section of Hematology Oncology, New York Harbor Health Care System, New York, NY; Division of Hematology and Medical Oncology, NYU Langone School of Medicine, New York, NY
| | - Yeun-Hee Park
- Section of Hematology Oncology, James J Peters VAMC, Bronx, NY; Division of Hematology/Oncology, Columbia Vagelos College of Physicians and Surgeons, New York, NY
| | - Susan Bates
- Section of Hematology Oncology, James J Peters VAMC, Bronx, NY; Division of Hematology/Oncology, Columbia Vagelos College of Physicians and Surgeons, New York, NY
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12
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Bourouh M, Marignani PA. The Tumor Suppressor Kinase LKB1: Metabolic Nexus. Front Cell Dev Biol 2022; 10:881297. [PMID: 35573694 PMCID: PMC9097215 DOI: 10.3389/fcell.2022.881297] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 04/07/2022] [Indexed: 11/13/2022] Open
Abstract
Liver kinase B1 (LKB1) is a multitasking tumor suppressor kinase that is implicated in multiple malignancies such as lung, gastrointestinal, pancreatic, and breast. LKB1 was first identified as the gene responsible for Peutz-Jeghers syndrome (PJS) characterized by hamartomatous polyps and oral mucotaneous pigmentation. LKB1 functions to activate AMP-activated protein kinase (AMPK) during energy stress to shift metabolic processes from active anabolic pathways to active catabolic pathways to generate ATP. Genetic loss or inactivation of LKB1 promotes metabolic reprogramming and metabolic adaptations of cancer cells that fuel increased growth and division rates. As a result, LKB1 loss is associated with increased aggressiveness and treatment options for patients with LKB1 mutant tumors are limited. Recently, there has been new insights into the role LKB1 has on metabolic regulation and the identification of potential vulnerabilities in LKB1 mutant tumors. In this review, we discuss the tumor suppressive role of LKB1 and the impact LKB1 loss has on metabolic reprograming in cancer cells, with a focus on lung cancer. We also discuss potential therapeutic avenues to treat malignancies associated with LKB1 loss by targeting aberrant metabolic pathways associated with LKB1 loss.
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Affiliation(s)
- Mohammed Bourouh
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Dalhousie University Halifax, Halifax, NS, Canada
| | - Paola A Marignani
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Dalhousie University Halifax, Halifax, NS, Canada
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13
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Omelchenko T. Cellular protrusions in 3D: Orchestrating early mouse embryogenesis. Semin Cell Dev Biol 2022; 129:63-74. [PMID: 35577698 DOI: 10.1016/j.semcdb.2022.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 05/04/2022] [Accepted: 05/04/2022] [Indexed: 12/26/2022]
Abstract
Cellular protrusions generated by the actin cytoskeleton are central to the process of building the body of the embryo. Problems with cellular protrusions underlie human diseases and syndromes, including implantation defects and pregnancy loss, congenital birth defects, and cancer. Cells use protrusive activity together with actin-myosin contractility to create an ordered body shape of the embryo. Here, I review how actin-rich protrusions are used by two major morphological cell types, epithelial and mesenchymal cells, during collective cell migration to sculpt the mouse embryo body. Pre-gastrulation epithelial collective migration of the anterior visceral endoderm is essential for establishing the anterior-posterior body axis. Gastrulation mesenchymal collective migration of the mesoderm wings is crucial for body elongation, and somite and heart formation. Analysis of mouse mutants with disrupted cellular protrusions revealed the key role of protrusions in embryonic morphogenesis and embryo survival. Recent technical approaches have allowed examination of the mechanisms that control cell and tissue movements in vivo in the complex 3D microenvironment of living mouse embryos. Advancing our understanding of protrusion-driven morphogenesis should provide novel insights into human developmental disorders and cancer metastasis.
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Affiliation(s)
- Tatiana Omelchenko
- Laboratory of Mammalian Cell Biology and Development, The Rockefeller University, 1230 York Avenue, New York 10065, USA.
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14
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LKB1 drives stasis and C/EBP-mediated reprogramming to an alveolar type II fate in lung cancer. Nat Commun 2022; 13:1090. [PMID: 35228570 PMCID: PMC8885825 DOI: 10.1038/s41467-022-28619-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 02/01/2022] [Indexed: 02/07/2023] Open
Abstract
LKB1 is among the most frequently altered tumor suppressors in lung adenocarcinoma. Inactivation of Lkb1 accelerates the growth and progression of oncogenic KRAS-driven lung tumors in mouse models. However, the molecular mechanisms by which LKB1 constrains lung tumorigenesis and whether the cancer state that stems from Lkb1 deficiency can be reverted remains unknown. To identify the processes governed by LKB1 in vivo, we generated an allele which enables Lkb1 inactivation at tumor initiation and subsequent Lkb1 restoration in established tumors. Restoration of Lkb1 in oncogenic KRAS-driven lung tumors suppressed proliferation and led to tumor stasis. Lkb1 restoration activated targets of C/EBP transcription factors and drove neoplastic cells from a progenitor-like state to a less proliferative alveolar type II cell-like state. We show that C/EBP transcription factors govern a subset of genes that are induced by LKB1 and depend upon NKX2-1. We also demonstrate that a defining factor of the alveolar type II lineage, C/EBPα, constrains oncogenic KRAS-driven lung tumor growth in vivo. Thus, this key tumor suppressor regulates lineage-specific transcription factors, thereby constraining lung tumor development through enforced differentiation.
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15
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Tiaojing Cuyun Recipe Enhances Pregnancy Outcome via the VEGF/PI3K/AKT/eNOS Signaling Pathway in EID Mice. DISEASE MARKERS 2022; 2022:9461444. [PMID: 35251378 PMCID: PMC8894059 DOI: 10.1155/2022/9461444] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 02/09/2022] [Indexed: 01/09/2023]
Abstract
Purpose. In this study, we evaluated the effect of Tiaojing Cuyun Recipe (TJCYR) on embryo implantation dysfunction- (EID-) induced damage of endometrial receptivity in mice and investigated the mechanisms underlying the effect. Methods. The main compounds of TJCYR were identified by high-performance liquid chromatography (HPLC). One hundred and twenty pregnant mice were randomly divided into six groups: control, EID only, progesterone (Prog)+EID, TJCYR-low-dose+EID, TJCYR-medium-dose+EID, and TJCYR-high-dose+EID. Mifepristone was injected to make the EID model. On the fourth day of pregnancy, serum was obtained to analyze hormone level by radioimmunoassay, the uterus was collected to analyze morphology by hematoxylin and eosin (H&E) and scanning electron microscopy (SEM), and a combination of immunofluorescence and Western blot was used to identify the related proteins. On the eighth day of pregnancy, the mice were sacrificed and the number of uterus-implanted blastocysts was counted. Results. Treatment with TJCYR significantly improved the number of implanted sites, the number of well-developed pinopodes, and microvascular formation in the mice. Moreover, TJCYR significantly activated PI3K/Akt/eNOS signaling pathways to promote angiogenesis, resulting in significantly improved endometrial receptivity and fertility outcomes when compared to the model group. Conclusion. These findings demonstrate that TJCYR was able to protect embryo implantation of EID mice due to TJCYR-mediated improvement in endometrial receptivity by promoting endometrial angiogenesis.
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16
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Zhao Q, Han YM, Song P, Liu Z, Yuan Z, Zou MH. Endothelial cell-specific expression of serine/threonine kinase 11 modulates dendritic cell differentiation. Nat Commun 2022; 13:648. [PMID: 35115536 PMCID: PMC8814147 DOI: 10.1038/s41467-022-28316-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 11/29/2021] [Indexed: 11/19/2022] Open
Abstract
In the bone marrow, classical and plasmacytoid dendritic cells (DC) develop from the macrophage-DC precursor (MDP) through a common DC precursor (CDP) step. This developmental process receives essential input from the niche in which it takes place, containing endothelial cells (EC) among other cell types. Here we show that targeted deletion of serine/threonine kinase 11 (Stk11) encoding tumor suppressor liver kinase b1 (Lkb1) in mouse ECs but not DCs, results in disrupted differentiation of MDPs to CDPs, severe reduction in mature DC numbers and spontaneous tumorigenesis. In wild type ECs, Lkb1 phosphorylates polypyrimidine tract binding protein 1 (Ptbp1) at threonine 138, which regulates stem cell factor (Scf) pre-mRNA splicing. In the absence of Lkb1, exon 6 of Scf is spliced out, leading to the loss of Scf secretion. Adeno-associated-virus-mediated delivery of genes encoding either soluble Scf or the phosphomimetic mutant Ptbp1T138E proteins rescued the defects of MDP to CDP differentiation and DC shortage in the endothelium specific Stk11 knockout mice. In summary, endothelial Stk11 expression regulates DC differentiation via modulation of Scf splicing, marking the Stk11-soluble-Scf axis as a potential cause of DC deficiency syndromes.
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Affiliation(s)
- Qiang Zhao
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303, USA
- Department of Cardiology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Young-Min Han
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303, USA
| | - Ping Song
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303, USA
| | - Zhixue Liu
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303, USA
| | - Zuyi Yuan
- Department of Cardiology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Ming-Hui Zou
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303, USA.
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17
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Modulating Tumor Microenvironment: A Review on STK11 Immune Properties and Predictive vs Prognostic Role for Non-small-cell Lung Cancer Immunotherapy. Curr Treat Options Oncol 2021; 22:96. [PMID: 34524570 DOI: 10.1007/s11864-021-00891-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2021] [Indexed: 01/07/2023]
Abstract
OPINION STATEMENT The quest for immunotherapy (IT) biomarkers is an element of highest clinical interest in both solid and hematologic tumors. In non-small-cell lung cancer (NSCLC) patients, besides PD-L1 expression evaluation with its intrinsic limitations, tissue and circulating parameters, likely portraying the tumor and its stromal/immune counterparts, have been proposed as potential predictors of IT responsiveness. STK11 mutations have been globally labeled as markers of IT resistance. After a thorough literature review, STK11 mutations condition the prognosis of NSCLC patients receiving ICI-containing regimens, implying a relevant biological and clinical significance. On the other hand, waiting for prospective and solid data, the putative negative predictive value of STK11 inactivation towards IT is sustained by less evidence. The physiologic regulation of multiple cellular pathways performed by STK11 likely explains the multifaceted modifications in tumor cells, stroma, and tumor immune microenvironment (TIME) observed in STK11 mutant lung cancer, particularly explored in the molecular subgroup of KRAS co-mutation. IT approaches available thus far in NSCLC, mainly represented by anti-PD-1/PD-L1 inhibitors, are not promising in the case of STK11 inactivation. Perceptive strategies aimed at modulating the TIME, regardless of STK11 status or specifically addressed to STK11-mutated cases, will hopefully provide valid therapeutic options to be adopted in the clinical practice.
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18
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Višnjić D, Lalić H, Dembitz V, Tomić B, Smoljo T. AICAr, a Widely Used AMPK Activator with Important AMPK-Independent Effects: A Systematic Review. Cells 2021. [PMID: 34064363 DOI: 10.3390/cellsl0051095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023] Open
Abstract
5-Aminoimidazole-4-carboxamide ribonucleoside (AICAr) has been one of the most commonly used pharmacological modulators of AMPK activity. The majority of early studies on the role of AMPK, both in the physiological regulation of metabolism and in cancer pathogenesis, were based solely on the use of AICAr as an AMPK-activator. Even with more complex models of AMPK downregulation and knockout being introduced, AICAr remained a regular starting point for many studies focusing on AMPK biology. However, there is an increasing number of studies showing that numerous AICAr effects, previously attributed to AMPK activation, are in fact AMPK-independent. This review aims to give an overview of the present knowledge on AMPK-dependent and AMPK-independent effects of AICAr on metabolism, hypoxia, exercise, nucleotide synthesis, and cancer, calling for caution in the interpretation of AICAr-based studies in the context of understanding AMPK signaling pathway.
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Affiliation(s)
- Dora Višnjić
- Laboratory of Cell Biology, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
- Department of Physiology, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Hrvoje Lalić
- Laboratory of Cell Biology, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
- Department of Physiology, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Vilma Dembitz
- Laboratory of Cell Biology, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
- Department of Physiology, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Barbara Tomić
- Laboratory of Cell Biology, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
- Department of Physiology, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Tomislav Smoljo
- Laboratory of Cell Biology, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
- Department of Physiology, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
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19
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AICAr, a Widely Used AMPK Activator with Important AMPK-Independent Effects: A Systematic Review. Cells 2021; 10:cells10051095. [PMID: 34064363 PMCID: PMC8147799 DOI: 10.3390/cells10051095] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/21/2021] [Accepted: 05/01/2021] [Indexed: 12/24/2022] Open
Abstract
5-Aminoimidazole-4-carboxamide ribonucleoside (AICAr) has been one of the most commonly used pharmacological modulators of AMPK activity. The majority of early studies on the role of AMPK, both in the physiological regulation of metabolism and in cancer pathogenesis, were based solely on the use of AICAr as an AMPK-activator. Even with more complex models of AMPK downregulation and knockout being introduced, AICAr remained a regular starting point for many studies focusing on AMPK biology. However, there is an increasing number of studies showing that numerous AICAr effects, previously attributed to AMPK activation, are in fact AMPK-independent. This review aims to give an overview of the present knowledge on AMPK-dependent and AMPK-independent effects of AICAr on metabolism, hypoxia, exercise, nucleotide synthesis, and cancer, calling for caution in the interpretation of AICAr-based studies in the context of understanding AMPK signaling pathway.
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20
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Beal R, Alonso-Carriazo Fernandez A, Grammatopoulos DK, Matter K, Balda MS. ARHGEF18/p114RhoGEF Coordinates PKA/CREB Signaling and Actomyosin Remodeling to Promote Trophoblast Cell-Cell Fusion During Placenta Morphogenesis. Front Cell Dev Biol 2021; 9:658006. [PMID: 33842485 PMCID: PMC8027320 DOI: 10.3389/fcell.2021.658006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 03/03/2021] [Indexed: 12/04/2022] Open
Abstract
Coordination of cell-cell adhesion, actomyosin dynamics and gene expression is crucial for morphogenetic processes underlying tissue and organ development. Rho GTPases are main regulators of the cytoskeleton and adhesion. They are activated by guanine nucleotide exchange factors in a spatially and temporally controlled manner. However, the roles of these Rho GTPase activators during complex developmental processes are still poorly understood. ARHGEF18/p114RhoGEF is a tight junction-associated RhoA activator that forms complexes with myosin II, and regulates actomyosin contractility. Here we show that p114RhoGEF/ARHGEF18 is required for mouse syncytiotrophoblast differentiation and placenta development. In vitro and in vivo experiments identify that p114RhoGEF controls expression of AKAP12, a protein regulating protein kinase A (PKA) signaling, and is required for PKA-induced actomyosin remodeling, cAMP-responsive element binding protein (CREB)-driven gene expression of proteins required for trophoblast differentiation, and, hence, trophoblast cell-cell fusion. Our data thus indicate that p114RhoGEF links actomyosin dynamics and cell-cell junctions to PKA/CREB signaling, gene expression and cell-cell fusion.
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Affiliation(s)
- Robert Beal
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | | | - Dimitris K Grammatopoulos
- Translational and Experimental Medicine, Warwick Medical School, Coventry, United Kingdom.,Department of Pathology, Institute of Precision Diagnostics and Translational Medicine, University Hospital Coventry and Warwickshire National Health Service (NHS) Trust, Coventry, United Kingdom
| | - Karl Matter
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Maria S Balda
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
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21
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Burger CA, Albrecht NE, Jiang D, Liang JH, Poché RA, Samuel MA. LKB1 and AMPK instruct cone nuclear position to modify visual function. Cell Rep 2021; 34:108698. [PMID: 33535040 PMCID: PMC7906279 DOI: 10.1016/j.celrep.2021.108698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 11/06/2020] [Accepted: 01/06/2021] [Indexed: 12/17/2022] Open
Abstract
Cone photoreceptors detect light and are responsible for color vision. These cells display a distinct polarized morphology where nuclei are precisely aligned in the apical retina. However, little is known about the mechanisms involved in cone nuclear positioning or the impact of this organization on retina function. We show that the serine/threonine kinase LKB1 and one of its substrates, AMPK, regulate cone nuclear positioning. In the absence of either molecule, cone nuclei are misplaced along the axon, resulting in altered nuclear lamination. LKB1 is required specifically in cones to mediate this process, and disruptions in nuclear alignment result in reduced cone function. Together, these results identify molecular determinants of cone nuclear position and indicate that cone nuclear position alignment enables proper visual function.
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Affiliation(s)
- Courtney A Burger
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA
| | - Nicholas E Albrecht
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA
| | - Danye Jiang
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA
| | - Justine H Liang
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ross A Poché
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Melanie A Samuel
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA.
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22
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Zhang K, Shi Y, Xu P, Huang C, Zhou C, Liu P, Hu R, Zhuang Y, Li G, Hu G, Guo X. Cloning and prokaryotic expression of the chicken liver kinase B1 (LKB1) and its localization in liver, heart and hypothalamus. Int J Biol Macromol 2020; 169:513-520. [PMID: 33385449 DOI: 10.1016/j.ijbiomac.2020.12.195] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/23/2020] [Accepted: 12/26/2020] [Indexed: 01/02/2023]
Abstract
Liver kinase B1 (LKB1) is a member of the serine/threonine kinase family, which plays an indispensable role in the organism of animals. In the current study, the chicken LKB1 protein gene was amplified by PCR based on the primers and cDNA templates. Then, the cloning vector was constructed and the target gene was cloned. After that, the target gene was inserted into the expression vector to construct the recombinant plasmid. The recombinant plasmid was transformed into BL21 (DE3) host cells and the LKB1 recombinant proteins were successfully expressed by using Isopropyl-β-D-thiogalactopyranoside (IPTG). Finally, purified LKB1 proteins were used as antigen and the rabbit-derived antiserums were collected. The antiserum titer determined by ELISA was not less than 1:128000. The results of Western blot suggested that the polyclonal antibody is highly specific to chicken LKB1 protein. Immunofluorescence indicated that the LKB1 protein is mainly expressed in the cytoplasm of liver, heart and hypothalamus cells of chicken. Our study showed that the LKB1 polyclonal antibodies produced by this method are effective and can be used to further study the role of LKB1 in the pathogenesis of chicken disease.
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Affiliation(s)
- Kun Zhang
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Yan Shi
- School of Computer and Information Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Puzhi Xu
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Cheng Huang
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Changming Zhou
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Ping Liu
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Ruiming Hu
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Yu Zhuang
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Guyue Li
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Guoliang Hu
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Xiaoquan Guo
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
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Zhang T, Li H, Ouyang C, Cao G, Gao J, Wu J, Yang J, Yu N, Min Q, Zhang C, Zhang W. Liver kinase B1 inhibits smooth muscle calcification via high mobility group box 1. Redox Biol 2020; 38:101828. [PMID: 33338919 PMCID: PMC7750422 DOI: 10.1016/j.redox.2020.101828] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/30/2020] [Accepted: 12/03/2020] [Indexed: 02/07/2023] Open
Abstract
Vascular calcification is a common pathological feature of atherosclerosis, chronic kidney disease, vascular injury, and aging. Liver kinase B1 (LKB1) plays pivotal roles in cellular processes such as apoptosis, metabolism, and cell cycle regulation. In addition, growing evidence has indicated that LKB1 functions as a tumor suppressor gene. However, its role in vascular calcification has not been reported. LKB1flox/flox mice were hybridized with SM22-CreERT2 transgenic mice and adult mice received tamoxifen to obtain smooth muscle-specific LKB1-knockout (LKB1SMKO) mice. LKB1 expression was decreased under calcifying conditions, and LKB1 overexpression had a protective effect on vascular calcification. However, high mobility group box 1 (HMGB1) overexpression partially counteracted the promotion of vascular calcification induced by LKB1 overexpression. Mechanically, LKB1 could bind to HMGB1 to promote HMGB1 degradation. Furthermore, LKB1SMKO mice showed intensified vascular calcification, which was alleviated by treatment with the HMGB1 inhibitor glycyrrhizic acid. Based on our results, LKB1 may inhibit vascular calcification via inhibiting HMGB1 expression. LKB1 expression was reduced under calcifying conditions. LKB1 overexpression had a protective effect on vascular calcification. Binding of LKB1 to HMGB1 promoted HMGB1 degradation. LKB1 may inhibit vascular calcification by inhibiting HMGB1 expression.
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Affiliation(s)
- Tianran Zhang
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Hongxuan Li
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Changhan Ouyang
- School of Pharmacy, Hubei University of Science and Technology, Xianning, Hubei, China
| | - Guangqing Cao
- Department of Cardiovascular Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Jiangang Gao
- School of Life Science and Key Laboratory of the Ministry of Education for Experimental Teratology, Shandong University, Jinan, China
| | - Jiliang Wu
- School of Pharmacy, Hubei University of Science and Technology, Xianning, Hubei, China
| | - Jianmin Yang
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Nengwang Yu
- Department of Urology, Qilu Hospital of Shandong University, Jinan, China
| | - Qing Min
- School of Pharmacy, Hubei University of Science and Technology, Xianning, Hubei, China.
| | - Cheng Zhang
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.
| | - Wencheng Zhang
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China; School of Pharmacy, Hubei University of Science and Technology, Xianning, Hubei, China.
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24
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Neuroprotective effects of SOX5 against ischemic stroke by regulating VEGF/PI3K/AKT pathway. Gene 2020; 767:145148. [PMID: 32949698 DOI: 10.1016/j.gene.2020.145148] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/07/2020] [Accepted: 09/11/2020] [Indexed: 01/28/2023]
Abstract
Ischemic stroke is a common clinical cardiovascular disease and often accompanied by central nervous system injury. It often causes paralysis or loss of motor function after central nervous system injury and significantly reduces the patient's quality of life. At present, there is no effective treatment strategy for nerve damage caused by ischemic stroke. Therefore, it is urgently need to explore effective treatment targets. The protein expression of SOX5, VEGF and apoptosis related proteins were measured by western blot. The mRNA expression of SOX5 and VEGF were detected by RT-qPCR. The concentration of S100B and GFAP which are related to nerve damage were detected using ELISA assay. The transcriptional regulation of SOX5 on VEGF was detected using ChIP-PCR and dual luciferase reporter gene assays. The cell apoptosis was measured by TUNEL assay and cell viability was detected by CCK-8 assay. In our study, we found that the expression of SOX5 was significantly reduced when LPS induced apoptosis in PC-12 cells. Overexpression of SOX5 repaired LPS-induced apoptosis. SOX5 promotes VEGF expression as a transcription factor to activate the PI3K/AKT pathway. VEGF also repairs nerve injury and brain tissue injury caused by ischemic stroke. In conclusion, SOX5 transcription regulates the expression of VEGF to activate the PI3K/AKT pathway, which repaired nerve damage caused by ischemic stroke. Therefore, SOX5 could be a new targetto regulate VEGF which can repair nerve injury induced by ischemic stroke.
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Summers ME, Richmond BW, Menon S, Sheridan RM, Kropski JA, Majka SA, Taketo MM, Bastarache JA, West JD, De Langhe S, Geraghty P, Klemm DJ, Chu HW, Friedman RS, Tao YK, Foronjy RF, Majka SM. Resident mesenchymal vascular progenitors modulate adaptive angiogenesis and pulmonary remodeling via regulation of canonical Wnt signaling. FASEB J 2020; 34:10267-10285. [PMID: 32533805 PMCID: PMC7496763 DOI: 10.1096/fj.202000629r] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/18/2020] [Accepted: 05/20/2020] [Indexed: 12/16/2022]
Abstract
Adaptive angiogenesis is necessary for tissue repair, however, it may also be associated with the exacerbation of injury and development of chronic disease. In these studies, we demonstrate that lung mesenchymal vascular progenitor cells (MVPC) modulate adaptive angiogenesis via lineage trace, depletion of MVPC, and modulation of β-catenin expression. Single cell sequencing confirmed MVPC as multipotential vascular progenitors, thus, genetic depletion resulted in alveolar simplification with reduced adaptive angiogenesis. Following vascular endothelial injury, Wnt activation in MVPC was sufficient to elicit an emphysema-like phenotype characterized by increased MLI, fibrosis, and MVPC driven adaptive angiogenesis. Lastly, activation of Wnt/β-catenin signaling skewed the profile of human and murine MVPC toward an adaptive phenotype. These data suggest that lung MVPC drive angiogenesis in response to injury and regulate the microvascular niche as well as subsequent distal lung tissue architecture via Wnt signaling.
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Affiliation(s)
- Megan E. Summers
- Department of MedicineDivision of Pulmonary, Critical Care & Sleep MedicineNational Jewish HealthDenverCOUSA
| | - Bradley W. Richmond
- Department of MedicineDivision of Allergy, Pulmonary and Critical Care Medicine or CardiologyVanderbilt University Medical CenterNashvilleTNUSA
| | - Swapna Menon
- Pulmonary Vascular Research Institute KochiAnalyzeDat Consulting ServicesErnakulamIndia
| | - Ryan M. Sheridan
- Department of Biochemistry and Molecular GeneticsRNA Bioscience InitiativeUniversity of Colorado School of MedicineAuroraCOUSA
| | - Jonathan A. Kropski
- Department of MedicineDivision of Allergy, Pulmonary and Critical Care Medicine or CardiologyVanderbilt University Medical CenterNashvilleTNUSA
| | - Sarah A. Majka
- Department of MedicineDivision of Pulmonary, Critical Care & Sleep MedicineNational Jewish HealthDenverCOUSA
| | - M. Mark Taketo
- Division of Experimental TherapeuticsGraduate School of MedicineKyoto UniversityKyotoJapan
| | - Julie A. Bastarache
- Department of MedicineDivision of Allergy, Pulmonary and Critical Care Medicine or CardiologyVanderbilt University Medical CenterNashvilleTNUSA
| | - James D. West
- Department of MedicineDivision of Allergy, Pulmonary and Critical Care Medicine or CardiologyVanderbilt University Medical CenterNashvilleTNUSA
| | | | - Patrick Geraghty
- Division of Pulmonary and Critical Care MedicineSUNY Downstate Medical CenterBrooklynNYUSA
| | - Dwight J. Klemm
- Department of Medicine, Pulmonary & Critical Care MedicineUniversity of ColoradoAuroraCOUSA
- Gates Center for Regenerative Medicine and Stem Cell BiologyUniversity of ColoradoAuroraCOUSA
| | - Hong Wei Chu
- Department of MedicineDivision of Pulmonary, Critical Care & Sleep MedicineNational Jewish HealthDenverCOUSA
| | | | - Yuankai K. Tao
- Pulmonary Vascular Research Institute KochiAnalyzeDat Consulting ServicesErnakulamIndia
| | - Robert F. Foronjy
- Division of Pulmonary and Critical Care MedicineSUNY Downstate Medical CenterBrooklynNYUSA
| | - Susan M. Majka
- Department of MedicineDivision of Pulmonary, Critical Care & Sleep MedicineNational Jewish HealthDenverCOUSA
- Gates Center for Regenerative Medicine and Stem Cell BiologyUniversity of ColoradoAuroraCOUSA
- Department of Biomedical ResearchNational Jewish HealthDenverCOUSA
- Biomedical EngineeringVanderbilt UniversityNashvilleTNUSA
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26
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Zhou S, Fu Y, Zhang XB, Pei M. Liver Kinase B1 Fine-Tunes Lineage Commitment of Human Fetal Synovium-Derived Stem Cells. J Orthop Res 2020; 38:258-268. [PMID: 31429977 PMCID: PMC7294510 DOI: 10.1002/jor.24449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 07/25/2019] [Indexed: 02/04/2023]
Abstract
Liver kinase B1 (LKB1), a serine/threonine protein, is a key regulator in stem cell function and energy metabolism. Herein, we describe the role of LKB1 in modulating the differentiation of synovium-derived stem cells (SDSCs) toward chondrogenic, adipogenic, and osteogenic lineages. Human fetal SDSCs were transduced with CRISPR associated protein 9 (Cas9)-single-guide RNA vectors to knockout or lentiviral vectors to overexpress the LKB1 gene. Analyses including ICE (Inference of CRISPR Edits) data from Sanger sequencing and quantitative polymerase chain reaction (qPCR) as well as Western blot demonstrated successful knockout (KO) or overexpression (OE) of LKB1 in human fetal SDSCs without any detectable side effects in morphology, proliferation rate, and cell cycle. LKB1 KO increased CD146 expression; interestingly, LKB1 OE increased SSEA4 level. The qPCR data showed that LKB1 KO upregulated the levels of SOX2 and NANOG while LKB1 OE lowered the expression of POU5F1 and KLF4. Furthermore, LKB1 KO enhanced, and LKB1 OE inhibited, chondrogenic and adipogenic differentiation potential. However, perhaps due to the inherent inability to achieve osteogenesis, LKB1 did not obviously affect osteogenic differentiation. These data demonstrate that LKB1 plays a significant role in determining human SDSCs' adipogenic and chondrogenic differentiation, which might provide an approach for fine-tuning the direction of stem cell differentiation in tissue engineering and regeneration. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:258-268, 2020.
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Affiliation(s)
- Sheng Zhou
- Stem Cell and Tissue Engineering Laboratory, Department of Orthopaedics, West Virginia University, Morgantown, WV, 26506, USA,Department of Sports Medicine and Adult Reconstructive Surgery, Drum Tower Hospital, School of Medicine, Nanjing University, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, China
| | - Yawen Fu
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Disease Hospital, Tianjin, China,Department of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Xiao-Bing Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Disease Hospital, Tianjin, China,Department of Medicine, Loma Linda University, Loma Linda, CA, USA,Co-corresponding author: Xiao-Bing Zhang, PhD. Division of Regenerative Medicine MC1528B, Department of Medicine, Loma Linda University, 11234 Anderson Street, Loma Linda, CA 92350, USA. Phone: 909-651-5886. Fax: 909-558-0428.
| | - Ming Pei
- Stem Cell and Tissue Engineering Laboratory, Department of Orthopaedics, West Virginia University, Morgantown, WV, 26506, USA,WVU Cancer Institute, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV, 26506, USA,Corresponding author: Ming Pei MD, PhD, Stem Cell and Tissue Engineering Laboratory, Department of Orthopaedics, West Virginia University, PO Box 9196, 64 Medical Center Drive, Morgantown, WV 26506-9196, USA, Telephone: 304-293-1072; Fax: 304-293-7070;
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27
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Islam MJ, Khan AM, Parves MR, Hossain MN, Halim MA. Prediction of Deleterious Non-synonymous SNPs of Human STK11 Gene by Combining Algorithms, Molecular Docking, and Molecular Dynamics Simulation. Sci Rep 2019; 9:16426. [PMID: 31712642 PMCID: PMC6848484 DOI: 10.1038/s41598-019-52308-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 10/09/2019] [Indexed: 02/08/2023] Open
Abstract
Serine-threonine kinase11 (STK11) is a tumor suppressor gene which plays a key role in regulating cell growth and apoptosis. It is widely known as a multitasking kinase and engaged in cell polarity, cell cycle arrest, chromatin remodeling, energy metabolism, and Wnt signaling. The substitutions of single amino acids in highly conserved regions of the STK11 protein are associated with Peutz-Jeghers syndrome (PJS), which is an autosomal dominant inherited disorder. The abnormal function of the STK11 protein is still not well understood. In this study, we classified disease susceptible single nucleotide polymorphisms (SNPs) in STK11 by using different computational algorithms. We identified the deleterious nsSNPs, constructed mutant protein structures, and evaluated the impact of mutation by employing molecular docking and molecular dynamics analysis. Our results show that W239R and W308C variants are likely to be highly deleterious mutations found in the catalytic kinase domain, which may destabilize structure and disrupt the activation of the STK11 protein as well as reduce its catalytic efficiency. The W239R mutant is likely to have a greater impact on destabilizing the protein structure compared to the W308C mutant. In conclusion, these mutants can help to further realize the large pool of disease susceptibilities linked with catalytic kinase domain activation of STK11 and assist to develop an effective drug for associated diseases.
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Affiliation(s)
- Md Jahirul Islam
- Division of Computer-Aided Drug Design, The Red-Green Research Centre, BICCB, 218 Elephant Road, Dhaka, 1205, Bangladesh
- Department of Biochemistry and Biotechnology, University of Science and Technology Chittagong (USTC), Foy's Lake, Khulshi- 4202, Chittagong, Bangladesh
| | - Akib Mahmud Khan
- Division of Computer-Aided Drug Design, The Red-Green Research Centre, BICCB, 218 Elephant Road, Dhaka, 1205, Bangladesh
| | - Md Rimon Parves
- Department of Biochemistry and Biotechnology, University of Science and Technology Chittagong (USTC), Foy's Lake, Khulshi- 4202, Chittagong, Bangladesh
| | - Md Nayeem Hossain
- Division of Computer-Aided Drug Design, The Red-Green Research Centre, BICCB, 218 Elephant Road, Dhaka, 1205, Bangladesh
| | - Mohammad A Halim
- Division of Computer-Aided Drug Design, The Red-Green Research Centre, BICCB, 218 Elephant Road, Dhaka, 1205, Bangladesh.
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28
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Li N, Wang Y, Neri S, Zhen Y, Fong LWR, Qiao Y, Li X, Chen Z, Stephan C, Deng W, Ye R, Jiang W, Zhang S, Yu Y, Hung MC, Chen J, Lin SH. Tankyrase disrupts metabolic homeostasis and promotes tumorigenesis by inhibiting LKB1-AMPK signalling. Nat Commun 2019; 10:4363. [PMID: 31554794 PMCID: PMC6761205 DOI: 10.1038/s41467-019-12377-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 09/06/2019] [Indexed: 12/28/2022] Open
Abstract
The LKB1/AMPK pathway plays a major role in cellular homeostasis and tumor suppression. Down-regulation of LKB1/AMPK occurs in several human cancers and has been implicated in metabolic diseases. However, the precise upstream regulation of LKB1-AMPK pathway is largely unknown. Here, we report that AMPK activation by LKB1 is regulated by tankyrases. Tankyrases interact with and ribosylate LKB1, promoting its K63-linked ubiquitination by an E3 ligase RNF146, which blocks LKB1/STRAD/MO25 complex formation and LKB1 activation. LKB1 activation by tankyrase inhibitors induces AMPK activation and suppresses tumorigenesis. Similarly, the tankyrase inhibitor G007-LK effectively regulates liver metabolism and glycemic control in diabetic mice in a LKB1-dependent manner. In patients with lung cancer, tankyrase levels negatively correlate with p-AMPK levels and poor survival. Taken together, these findings suggest that tankyrase and RNF146 are major up-stream regulators of LKB1-AMPK pathway and provide another focus for cancer and metabolic disease therapies.
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Affiliation(s)
- Nan Li
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
| | - Yifan Wang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
- The University of Texas Graduate School of Biomedical Sciences Houston, Houston, TX, 77030, USA
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, 75219, USA
| | - Shinya Neri
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Yuanli Zhen
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Lon Wolf R Fong
- The University of Texas Graduate School of Biomedical Sciences Houston, Houston, TX, 77030, USA
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Yawei Qiao
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Xu Li
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
- School of Life Science, Westlake University, Hangzhou, 310024, China
| | - Zhen Chen
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Clifford Stephan
- Center for Translational Cancer Research, The Institute of Biosciences and Technology at Texas A&M University, Houston, TX, 77030, USA
| | - Weiye Deng
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, 75219, USA
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Rui Ye
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
- The University of Texas Graduate School of Biomedical Sciences Houston, Houston, TX, 77030, USA
| | - Wen Jiang
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, 75219, USA
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Shuxing Zhang
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Yonghao Yu
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Mien-Chie Hung
- The University of Texas Graduate School of Biomedical Sciences Houston, Houston, TX, 77030, USA
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Junjie Chen
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
- The University of Texas Graduate School of Biomedical Sciences Houston, Houston, TX, 77030, USA.
| | - Steven H Lin
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
- The University of Texas Graduate School of Biomedical Sciences Houston, Houston, TX, 77030, USA.
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
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29
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Zhou S, Li Y, Qiao L, Ge Y, Huang X, Gao X, Ju H, Wang W, Zhang J, Yan J, Teng H, Jiang Q. Inactivation of Lkb1 in postnatal chondrocytes leads to epiphyseal growth-plate abnormalities and promotes enchondroma-like formation. FASEB J 2019; 33:9476-9488. [PMID: 31091421 DOI: 10.1096/fj.201900294rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Liver serine-threonine kinase B1 (LKB1) is a tumor suppressor that has been linked to many types of tumors. However, the role of LKB1 in cartilaginous tumorigenesis is still poorly understood. In this study, we find that cartilage-specific, tamoxifen-inducible Lkb1 knockout results in multiple enchondroma-like lesions adjacent to the disorganized growth plates. We showed that chondrocytes retain an immature status caused by loss of Lkb1, which may lead to the dramatic expansion of growth-plate cartilage and the formation of enchondroma-like lesions. Additionally, increased mammalian target of rapamycin complex 1 (mTORC1) activity is observed in the Lkb1 conditional knockout (cKO) chondrocytes, and rapamycin (mTORC1 inhibitor) treatment significantly alleviates the expansion of growth-plate cartilage and eliminates the enchondroma-like lesions in Lkb1 cKO mice. Thus, our findings indicate that loss of Lkb1 leads to the expansion of chondrocytes and the formation of enchondroma-like lesions during postnatal cartilage development, and that the up-regulated mTORC1-signaling pathway is implicated in this process. Our findings suggest that modulation of LKB1 and related signaling is a potential therapy in cartilaginous tumorigenesis.-Zhou, S., Li, Y., Qiao, L., Ge, Y., Huang, X., Gao, X., Ju, H., Wang, W., Zhang, J., Yan, J., Teng, H., Jiang, Q. Inactivation of Lkb1 in postnatal chondrocytes leads to epiphyseal growth-plate abnormalities and promotes enchondroma-like formation.
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Affiliation(s)
- Sheng Zhou
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Sports Medicine and Adult Reconstructive Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Yixuan Li
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Sports Medicine and Adult Reconstructive Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Liang Qiao
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Sports Medicine and Adult Reconstructive Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Yuxiang Ge
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Sports Medicine and Adult Reconstructive Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | | | - Xiang Gao
- Model Animal Research Center (MARC), Nanjing, China
| | | | - Wei Wang
- Nanjing University, Nanjing, China
| | | | - Jun Yan
- Model Animal Research Center (MARC), Nanjing, China
| | - Huajian Teng
- Model Animal Research Center (MARC), Nanjing, China
| | - Qing Jiang
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Sports Medicine and Adult Reconstructive Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China.,Model Animal Research Center (MARC), Nanjing, China
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30
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Smooth muscle-specific LKB1 deletion exaggerates angiotensin II-induced abdominal aortic aneurysm in mice. J Mol Cell Cardiol 2019; 130:131-139. [DOI: 10.1016/j.yjmcc.2019.03.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 03/12/2019] [Accepted: 03/27/2019] [Indexed: 11/19/2022]
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31
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Han Y, Feng H, Sun J, Liang X, Wang Z, Xing W, Dai Q, Yang Y, Han A, Wei Z, Bi Q, Ji H, Kang T, Zou W. Lkb1 deletion in periosteal mesenchymal progenitors induces osteogenic tumors through mTORC1 activation. J Clin Invest 2019; 129:1895-1909. [PMID: 30830877 PMCID: PMC6486357 DOI: 10.1172/jci124590] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Bone osteogenic sarcoma has a poor prognosis as the exact cell of origin and the signaling pathways underling tumor formation remain undefined. Here, we report an osteogenic tumor mouse model based on the conditional knockout of liver kinase b1 (Lkb1; also known as Stk11) in Cathepsin K (Ctsk)-Cre expressing cells. Lineage tracing studies demonstrated that Ctsk-Cre could label a population of periosteal cells. The cells functioned as mesenchymal progenitors with regard to markers and functional properties. LKB1 deficiency increased proliferation and osteoblast differentiation of Ctsk+ periosteal cells, while downregulation of mTORC1 activity, using Raptor genetic mouse model or mTORC1 inhibitor treatment, ameliorated tumor progression of Ctsk-Cre Lkb1fllfl mice. Xenograft mouse models, using human osteosarcoma cell lines, also demonstrated that LKB1 deficiency promoted tumor formation, while mTOR inhibition suppressed xenograft tumor growth. In summary, we identified periosteum-derived Ctsk-Cre expressing cells as a cell of origin for osteogenic tumor and suggested the LKB1-mTORC1 pathway as a promising target for treatment of osteogenic tumor.
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Affiliation(s)
- Yujiao Han
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Heng Feng
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Jun Sun
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Xiaoting Liang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Zhuo Wang
- Department of Pathology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Wenhui Xing
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Qinggang Dai
- The Second Dental Center, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yang Yang
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Anjia Han
- Department of Pathology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Zhanying Wei
- Department of Osteoporosis and Bone Diseases, Metabolic Bone Disease and Genetics Research Unit, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Qing Bi
- Zhejiang Provincial People’s Hospital, Hangzhou, China
| | - Hongbin Ji
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
- School of Life Science and Technology, Shanghai Tech University, Shanghai, China
| | - Tiebang Kang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Weiguo Zou
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
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32
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Sawada N, Arany Z. Metabolic Regulation of Angiogenesis in Diabetes and Aging. Physiology (Bethesda) 2018; 32:290-307. [PMID: 28615313 DOI: 10.1152/physiol.00039.2016] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 02/24/2017] [Accepted: 04/05/2017] [Indexed: 12/16/2022] Open
Abstract
Impaired angiogenesis and endothelial dysfunction are hallmarks of diabetes and aging. Clinical efforts at promoting angiogenesis have largely focused on growth factor pathways, with mixed results. Recently, a new repertoire of endothelial intracellular molecules critical to endothelial metabolism has emerged as playing an important role in regulating angiogenesis. This review thus focuses on the emerging importance and therapeutic potential of these proteins and of endothelial bioenergetics in diabetes and aging.
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Affiliation(s)
- Naoki Sawada
- Department of Cell Biology and Molecular Medicine, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, New Jersey.,Department of Cell Biology and Molecular Medicine, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, New Jersey.,Division of Rheumatology, Endocrinology and Nephrology, Hokkaido University Graduate School of Medicine, Sapporo, Japan; and
| | - Zolt Arany
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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33
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Momcilovic M, Bailey ST, Lee JT, Zamilpa C, Jones A, Abdelhady G, Mansfield J, Francis KP, Shackelford DB. Utilizing 18F-FDG PET/CT Imaging and Quantitative Histology to Measure Dynamic Changes in the Glucose Metabolism in Mouse Models of Lung Cancer. J Vis Exp 2018. [PMID: 30080208 PMCID: PMC6126521 DOI: 10.3791/57167] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
A hallmark of advanced tumors is a switch to aerobic glycolysis that is readily measured by [18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography (18F-FDG PET) imaging. Co-mutations in the KRAS proto-oncogene and the LKB1 tumor suppressor gene are frequent events in lung cancer that drive hypermetabolic, glycolytic tumor growth. A critical pathway regulating the growth and metabolism of these tumors is the mechanistic target of the rapamycin (mTOR) pathway, which can be effectively targeted using selective catalytic mTOR kinase inhibitors. The mTOR inhibitor MLN0128 suppresses glycolysis in mice bearing tumors with Kras and Lkb1 co-mutations, referred to as KL mice. The therapy response in KL mice is first measured by 18F-FDG PET and computed tomography (CT) imaging before and after the delivery of MLN0128. By utilizing 18F-FDG PET/CT, researchers are able to measure dynamic changes in the glucose metabolism in genetically engineered mouse models (GEMMs) of lung cancer following a therapeutic intervention with targeted therapies. This is followed by ex vivo autoradiography and a quantitative immunohistochemical (qIHC) analysis using morphometric software. The use of qIHC enables the detection and quantification of distinct changes in the biomarker profiles following treatment as well as the characterization of distinct tumor pathologies. The coupling of PET imaging to quantitative histology is an effective strategy to identify metabolic and therapeutic responses in vivo in mouse models of disease.
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Affiliation(s)
- Milica Momcilovic
- Division of Pulmonary and Critical Care Medicine, University of California Los Angeles David Geffen School of Medicine
| | | | - Jason T Lee
- Department of Molecular and Medical Pharmacology, University of California Los Angeles
| | - Charles Zamilpa
- Department of Molecular and Medical Pharmacology, University of California Los Angeles
| | - Anthony Jones
- Department of Molecular and Medical Pharmacology, University of California Los Angeles
| | - Gihad Abdelhady
- Division of Pulmonary and Critical Care Medicine, University of California Los Angeles David Geffen School of Medicine
| | | | - Kevin P Francis
- Division of Orthopaedic Surgery, University of California Los Angeles David Geffen School of Medicine
| | - David B Shackelford
- Division of Pulmonary and Critical Care Medicine, University of California Los Angeles David Geffen School of Medicine;
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34
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Bai B, Man AWC, Yang K, Guo Y, Xu C, Tse HF, Han W, Bloksgaard M, De Mey JGR, Vanhoutte PM, Xu A, Wang Y. Endothelial SIRT1 prevents adverse arterial remodeling by facilitating HERC2-mediated degradation of acetylated LKB1. Oncotarget 2018; 7:39065-39081. [PMID: 27259994 PMCID: PMC5129914 DOI: 10.18632/oncotarget.9687] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/23/2016] [Indexed: 11/25/2022] Open
Abstract
Aims-SIRT1 exerts potent activity against cellular senescence and vascular ageing. By decreasing LKB1 protein levels, it promotes the survival and regeneration of endothelial cells. The present study aims to investigate the molecular mechanisms underlying SIRT1-mediated LKB1 degradation for the prevention of vascular ageing. Methods and Results-Co-immunoprecipitation assay demonstrated that SIRT1, via its amino-terminus, binds to the DOC domain of HERC2 [HECT and RLD domain containing E3 ubiquitin protein ligase 2], which then ubiquitinates LKB1 in the nuclear compartment of endothelial cells. Site-directed mutagenesis revealed that acetylation at lysine (K) 64 of LKB1 triggers the formation of SIRT1/HERC2/LKB1 protein complex and subsequent proteasomal degradation. In vitro cellular studies suggested that accumulation of acetylated LKB1 in the nucleus leads to endothelial activation, in turn stimulating the proliferation of vascular smooth muscle cells and the production of extracellular matrix proteins. Chromatin immunoprecipitation quantitative PCR confirmed that acetylated LKB1 interacts with and activates TGFβ1 promoter, which is inhibited by SIRT1. Knocking down either SIRT1 or HERC2 results in an increased association of LKB1 with the positive regulatory elements of TGFβ1 promoter. In mice without endothelial nitric oxide synthase, selective overexpression of human SIRT1 in endothelium prevents hypertension and age-related adverse arterial remodeling. Lentiviral-mediated knockdown of HERC2 abolishes the beneficial effects of endothelial SIRT1 on both arterial remodeling and arterial blood pressure control. Conclusion-By downregulating acetylated LKB1 protein via HERC2, SIRT1 fine-tunes the crosstalk between endothelial and vascular smooth muscle cells to prevent adverse arterial remodeling and maintain vascular homeostasis.
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Affiliation(s)
- Bo Bai
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China.,Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Andy W C Man
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China
| | - Kangmin Yang
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China
| | - Yumeng Guo
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China
| | - Cheng Xu
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China
| | - Hung-Fat Tse
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Weiping Han
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Maria Bloksgaard
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Jo G R De Mey
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Paul M Vanhoutte
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China
| | - Aimin Xu
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China.,Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Yu Wang
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China
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35
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Ollila S, Domènech-Moreno E, Laajanen K, Wong IP, Tripathi S, Pentinmikko N, Gao Y, Yan Y, Niemelä EH, Wang TC, Viollet B, Leone G, Katajisto P, Vaahtomeri K, Mäkelä TP. Stromal Lkb1 deficiency leads to gastrointestinal tumorigenesis involving the IL-11-JAK/STAT3 pathway. J Clin Invest 2017; 128:402-414. [PMID: 29202476 DOI: 10.1172/jci93597] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 10/24/2017] [Indexed: 12/12/2022] Open
Abstract
Germline mutations in the gene encoding tumor suppressor kinase LKB1 lead to gastrointestinal tumorigenesis in Peutz-Jeghers syndrome (PJS) patients and mouse models; however, the cell types and signaling pathways underlying tumor formation are unknown. Here, we demonstrated that mesenchymal progenitor- or stromal fibroblast-specific deletion of Lkb1 results in fully penetrant polyposis in mice. Lineage tracing and immunohistochemical analyses revealed clonal expansion of Lkb1-deficient myofibroblast-like cell foci in the tumor stroma. Loss of Lkb1 in stromal cells was associated with induction of an inflammatory program including IL-11 production and activation of the JAK/STAT3 pathway in tumor epithelia concomitant with proliferation. Importantly, treatment of LKB1-defcient mice with the JAK1/2 inhibitor ruxolitinib dramatically decreased polyposis. These data indicate that IL-11-mediated induction of JAK/STAT3 is critical in gastrointestinal tumorigenesis following Lkb1 mutations and suggest that targeting this pathway has therapeutic potential in Peutz-Jeghers syndrome.
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Affiliation(s)
- Saara Ollila
- Research Programs Unit, Faculty of Medicine and.,HiLIFE-Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland.,Division of Digestive and Liver Diseases, Department of Medicine, Irving Cancer Research Center, Columbia University Medical Center, New York, New York, USA
| | - Eva Domènech-Moreno
- Research Programs Unit, Faculty of Medicine and.,HiLIFE-Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Kaisa Laajanen
- Research Programs Unit, Faculty of Medicine and.,HiLIFE-Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Iris Pl Wong
- Research Programs Unit, Faculty of Medicine and.,HiLIFE-Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Sushil Tripathi
- Research Programs Unit, Faculty of Medicine and.,HiLIFE-Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Nalle Pentinmikko
- Institute of Biotechnology, HiLIFE Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Yajing Gao
- Research Programs Unit, Faculty of Medicine and.,HiLIFE-Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Yan Yan
- Research Programs Unit, Faculty of Medicine and.,HiLIFE-Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Elina H Niemelä
- Research Programs Unit, Faculty of Medicine and.,HiLIFE-Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Timothy C Wang
- Division of Digestive and Liver Diseases, Department of Medicine, Irving Cancer Research Center, Columbia University Medical Center, New York, New York, USA
| | - Benoit Viollet
- INSERM, U1016, Institut Cochin, Paris, France.,CNRS, UMR8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, France
| | - Gustavo Leone
- Department of Cancer Biology and Genetics, College of Medicine, Department of Molecular Genetics, College of Biological Sciences, and Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio, USA
| | - Pekka Katajisto
- HiLIFE-Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland.,Institute of Biotechnology, HiLIFE Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland.,Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
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36
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Zhang C, Xiao X, Chen M, Aldharee H, Chen Y, Long W. Liver kinase B1 restoration promotes exosome secretion and motility of lung cancer cells. Oncol Rep 2017; 39:376-382. [PMID: 29138862 PMCID: PMC5783601 DOI: 10.3892/or.2017.6085] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 10/24/2017] [Indexed: 12/13/2022] Open
Abstract
Liver kinase B1 (LKB1) regulates a variety of cellular functions, including cell polarity, energy metabolism and cell growth, by targeting multiple signaling pathways such as AMPK/mTOR and p53. LKB1 functions as a tumor suppressor in sporadic cancers including lung cancer. Extracellular vesicles such as exosomes secreted by cancer cells modulate the tumor microenvironment and progression by targeting both tumor cells (autocrine actions) and other types of cells associated with tumors (paracrine actions). While the roles of LKB1 in cellular signaling in general is well-studied, its specific role in exosome-mediated signaling remains to be explored. To this purpose, we reintroduced LKB1 into H460 and A549 lung cancer cells that are endogenously deficient in LKB1 expression. Notably, we found that while restoration of LKB1 significantly reduced lung cancer cell growth as expected, it greatly promoted cell motility and enhanced the release of exosomes. In addition, exosomes isolated from H460 cells with stable restoration of LKB1 had much higher ability in stimulating lung cancer cell migration than did those from H460 cells lacking LKB1. Mechanistically, restoration of LKB1 in H460 cells inhibited cellular expression and exosomal secretion of migration-suppressing microRNAs (miRNAs), including miR-125a, miR-126 and let7b. Taken together, the present study revealed a new role for LKB1 in promoting cell motility by downregulating migration-suppressing miRNA expression and exosome secretion.
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Affiliation(s)
- Cheng Zhang
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA
| | - Xiang Xiao
- Department of Pharmacology and Toxicology, Wright State University, Dayton, OH 45435, USA
| | - Minyi Chen
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA
| | - Hitham Aldharee
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA
| | - Yanfang Chen
- Department of Pharmacology and Toxicology, Wright State University, Dayton, OH 45435, USA
| | - Weiwen Long
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA
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37
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Kropski JA, Richmond BW, Gaskill CF, Foronjy RF, Majka SM. Deregulated angiogenesis in chronic lung diseases: a possible role for lung mesenchymal progenitor cells (2017 Grover Conference Series). Pulm Circ 2017; 8:2045893217739807. [PMID: 29040010 PMCID: PMC5731726 DOI: 10.1177/2045893217739807] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Chronic lung disease (CLD), including pulmonary fibrosis (PF) and chronic obstructive pulmonary disease (COPD), is the fourth leading cause of mortality worldwide. Both are debilitating pathologies that impede overall tissue function. A common co-morbidity in CLD is vasculopathy, characterized by deregulated angiogenesis, remodeling, and loss of microvessels. This substantially worsens prognosis and limits survival, with most current therapeutic strategies being largely palliative. The relevance of angiogenesis, both capillary and lymph, to the pathophysiology of CLD has not been resolved as conflicting evidence depicts angiogenesis as both reparative or pathologic. Therefore, we must begin to understand and model the underlying pathobiology of pulmonary vascular deregulation, alone and in response to injury induced disease, to define cell interactions necessary to maintain normal function and promote repair. Capillary and lymphangiogenesis are deregulated in both PF and COPD, although the mechanisms by which they co-regulate and underlie early pathogenesis of disease are unknown. The cell-specific mechanisms that regulate lung vascular homeostasis, repair, and remodeling represent a significant gap in knowledge, which presents an opportunity to develop targeted therapies. We have shown that that ABCG2pos multipotent adult mesenchymal stem or progenitor cells (MPC) influence the function of the capillary microvasculature as well as lymphangiogenesis. A balance of both is required for normal tissue homeostasis and repair. Our current models suggest that when lymph and capillary angiogenesis are out of balance, the non-equivalence appears to support the progression of disease and tissue remodeling. The angiogenic regulatory mechanisms underlying CLD likely impact other interstitial lung diseases, tuberous sclerosis, and lymphangioleiomyomatosis.
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Affiliation(s)
- Jonathan A Kropski
- 1 12328 Department of Medicine, Division of Allergy, Pulmonary and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Bradley W Richmond
- 1 12328 Department of Medicine, Division of Allergy, Pulmonary and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Christa F Gaskill
- 1 12328 Department of Medicine, Division of Allergy, Pulmonary and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Robert F Foronjy
- 3 5718 Department of Medicine, Vanderbilt University, Nashville, TN, USA
| | - Susan M Majka
- 1 12328 Department of Medicine, Division of Allergy, Pulmonary and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.,2 74498 Department of Medicine, Division of Pulmonary and Critical Care Medicine, SUNY Downstate Medical Center, Brooklyn, NY, USA
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38
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Liu Z, Zhu H, Dai X, Wang C, Ding Y, Song P, Zou MH. Macrophage Liver Kinase B1 Inhibits Foam Cell Formation and Atherosclerosis. Circ Res 2017; 121:1047-1057. [PMID: 28827412 PMCID: PMC5640502 DOI: 10.1161/circresaha.117.311546] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/13/2017] [Accepted: 08/21/2017] [Indexed: 01/01/2023]
Abstract
RATIONALE LKB1 (liver kinase B1) is a serine/threonine kinase and tumor suppressor, which regulates the homeostasis of hematopoietic cells and immune responses. Macrophages transform into foam cells upon taking-in lipids. No role for LKB1 in foam cell formation has previously been reported. OBJECTIVE We sought to establish the role of LKB1 in atherosclerotic foam cell formation. METHODS AND RESULTS LKB1 expression was examined in human carotid atherosclerotic plaques and in western diet-fed atherosclerosis-prone Ldlr-/- and ApoE-/- mice. LKB1 expression was markedly reduced in human plaques when compared with nonatherosclerotic vessels. Consistently, time-dependent reduction of LKB1 levels occurred in atherosclerotic lesions in western diet-fed Ldlr-/- and ApoE-/- mice. Exposure of macrophages to oxidized low-density lipoprotein downregulated LKB1 in vitro. Furthermore, LKB1 deficiency in macrophages significantly increased the expression of SRA (scavenger receptor A), modified low-density lipoprotein uptake and foam cell formation, all of which were abolished by blocking SRA. Further, we found LKB1 phosphorylates SRA resulting in its lysosome degradation. To further investigate the role of macrophage LKB1 in vivo, ApoE-/-LKB1fl/flLysMcre and ApoE-/-LKB1fl/fl mice were fed with western diet for 16 weeks. Compared with ApoE-/-LKB1fl/fl wild-type control, ApoE-/-LKB1fl/flLysMcre mice developed more atherosclerotic lesions in whole aorta and aortic root area, with markedly increased SRA expression in aortic root lesions. CONCLUSIONS We conclude that macrophage LKB1 reduction caused by oxidized low-density lipoprotein promotes foam cell formation and the progression of atherosclerosis.
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Affiliation(s)
- Zhaoyu Liu
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Huaiping Zhu
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Xiaoyan Dai
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Cheng Wang
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Ye Ding
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Ping Song
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Ming-Hui Zou
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta.
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39
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LKB1 as a Tumor Suppressor in Uterine Cancer: Mouse Models and Translational Studies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 943:211-241. [PMID: 27910069 DOI: 10.1007/978-3-319-43139-0_7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The LKB1 tumor suppressor was identified in 1998 as the gene mutated in the Peutz-Jeghers Syndrome (PJS), a hereditary cancer predisposition characterized by gastrointestinal polyposis and a high incidence of cancers, particularly carcinomas, at a variety of anatomic sites including the gastrointestinal tract, lung, and female reproductive tract. Women with PJS have a high incidence of carcinomas of the uterine corpus (endometrium) and cervix. The LKB1 gene is also somatically mutated in human cancers arising at these sites. Work in mouse models has highlighted the potency of LKB1 as an endometrial tumor suppressor and its distinctive roles in driving invasive and metastatic growth. These in vivo models represent tractable experimental systems for the discovery of underlying biological principles and molecular processes regulated by LKB1 in the context of tumorigenesis and also serve as useful preclinical model systems for experimental therapeutics. Here we review LKB1's known roles in mTOR signaling, metabolism, and cell polarity, with an emphasis on human pathology and mouse models relevant to uterine carcinogenesis, including cancers of the uterine corpus and cervix.
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40
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The tumor suppressor LKB1 regulates starvation-induced autophagy under systemic metabolic stress. Sci Rep 2017; 7:7327. [PMID: 28779098 PMCID: PMC5544676 DOI: 10.1038/s41598-017-07116-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 06/21/2017] [Indexed: 12/19/2022] Open
Abstract
Autophagy is an evolutionarily conserved process that degrades cellular components to restore energy homeostasis under limited nutrient conditions. How this starvation-induced autophagy is regulated at the whole-body level is not fully understood. Here, we show that the tumor suppressor Lkb1, which activates the key energy sensor AMPK, also regulates starvation-induced autophagy at the organismal level. Lkb1-deficient zebrafish larvae fail to activate autophagy in response to nutrient restriction upon yolk termination, shown by reduced levels of the autophagy-activating proteins Atg5, Lc3-II and Becn1, and aberrant accumulation of the cargo receptor and autophagy substrate p62. We demonstrate that the autophagy defect in lkb1 mutants can be partially rescued by inhibiting mTOR signaling but not by inhibiting the PI3K pathway. Interestingly, mTOR-independent activation of autophagy restores degradation of the aberrantly accumulated p62 in lkb1 mutants and prolongs their survival. Our data uncover a novel critical role for Lkb1 in regulating starvation-induced autophagy at the organismal level, providing mechanistic insight into metabolic adaptation during development.
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41
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Sengupta S, Nagalingam A, Muniraj N, Bonner MY, Mistriotis P, Afthinos A, Kuppusamy P, Lanoue D, Cho S, Korangath P, Shriver M, Begum A, Merino VF, Huang CY, Arbiser JL, Matsui W, Győrffy B, Konstantopoulos K, Sukumar S, Marignani PA, Saxena NK, Sharma D. Activation of tumor suppressor LKB1 by honokiol abrogates cancer stem-like phenotype in breast cancer via inhibition of oncogenic Stat3. Oncogene 2017; 36:5709-5721. [PMID: 28581518 DOI: 10.1038/onc.2017.164] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 04/09/2017] [Accepted: 04/10/2017] [Indexed: 12/12/2022]
Abstract
Tumor suppressor and upstream master kinase Liver kinase B1 (LKB1) plays a significant role in suppressing cancer growth and metastatic progression. We show that low-LKB1 expression significantly correlates with poor survival outcome in breast cancer. In line with this observation, loss-of-LKB1 rendered breast cancer cells highly migratory and invasive, attaining cancer stem cell-like phenotype. Accordingly, LKB1-null breast cancer cells exhibited an increased ability to form mammospheres and elevated expression of pluripotency-factors (Oct4, Nanog and Sox2), properties also observed in spontaneous tumors in Lkb1-/- mice. Conversely, LKB1-overexpression in LKB1-null cells abrogated invasion, migration and mammosphere-formation. Honokiol (HNK), a bioactive molecule from Magnolia grandiflora increased LKB1 expression, inhibited individual cell-motility and abrogated the stem-like phenotype of breast cancer cells by reducing the formation of mammosphere, expression of pluripotency-factors and aldehyde dehydrogenase activity. LKB1, and its substrate, AMP-dependent protein kinase (AMPK) are important for HNK-mediated inhibition of pluripotency factors since LKB1-silencing and AMPK-inhibition abrogated, while LKB1-overexpression and AMPK-activation potentiated HNK's effects. Mechanistic studies showed that HNK inhibited Stat3-phosphorylation/activation in an LKB1-dependent manner, preventing its recruitment to canonical binding-sites in the promoters of Nanog, Oct4 and Sox2. Thus, inhibition of the coactivation-function of Stat3 resulted in suppression of expression of pluripotency factors. Further, we showed that HNK inhibited breast tumorigenesis in mice in an LKB1-dependent manner. Molecular analyses of HNK-treated xenografts corroborated our in vitro mechanistic findings. Collectively, these results present the first in vitro and in vivo evidence to support crosstalk between LKB1, Stat3 and pluripotency factors in breast cancer and effective anticancer modulation of this axis with HNK treatment.
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Affiliation(s)
- S Sengupta
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - A Nagalingam
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - N Muniraj
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - M Y Bonner
- Department of Dermatology, Emory University School of Medicine, Winship Cancer Institute, Atlanta, GA, USA
| | - P Mistriotis
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore MD, USA
| | - A Afthinos
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore MD, USA
| | - P Kuppusamy
- Department of Medicine, University of Maryland School of Medicine, Baltimore MD, USA
| | - D Lanoue
- Department of Biochemistry and Molecular Biology, Dalhousie University, Nova Scotia Canada
| | - S Cho
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - P Korangath
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - M Shriver
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - A Begum
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - V F Merino
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - C-Y Huang
- Division of Biostatistics and Bioinformatics, the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD, USA
| | - J L Arbiser
- Department of Dermatology, Emory University School of Medicine, Winship Cancer Institute, Atlanta, GA, USA.,Atlanta Veterans Administration Medical Center, Atlanta, GA, USA
| | - W Matsui
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - B Győrffy
- MTA TTK Momentum Cancer Biomarker Research Group, Budapest, Hungary.,Semmelweis University 2nd Department of Pediatrics, Budapest, Hungary
| | - K Konstantopoulos
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore MD, USA
| | - S Sukumar
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
| | - P A Marignani
- Department of Biochemistry and Molecular Biology, Dalhousie University, Nova Scotia Canada
| | - N K Saxena
- Department of Medicine, University of Maryland School of Medicine, Baltimore MD, USA
| | - D Sharma
- Department of Oncology, Johns Hopkins University School of Medicine and the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore MD, USA
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42
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Makker A, Goel MM, Mahdi AA, Bhatia V, Das V, Agarwal A, Pandey A. PI3K/Akt/mTOR signaling & its regulator tumour suppressor genes PTEN & LKB1 in human uterine leiomyomas. Indian J Med Res 2017; 143:S112-S119. [PMID: 27748285 PMCID: PMC5080920 DOI: 10.4103/0971-5916.191808] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Background & objectives: Despite their high occurrence and associated significant level of morbidity manifesting as spectrum of clinical symptoms, the pathogenesis of uterine leiomyomas (ULs) remains unclear. We investigated expression profile of tumour suppressor genes PTEN (phosphatase and tensin homolog deleted on chromosome ten) and LKB1 (liver kinase B1), and key signaling components of P13K (phosphatidylinositol 3-kinase)/Akt (protein kinase B)/mTOR (mammalian target of rapamycin) pathway in leiomyomas and adjacent normal myometrium in women of reproductive age, to explore the possibility of targeting this pathway for future therapeutic implications. Methods: Real time PCR (qPCR) was used to quantify relative gene expression levels of PTEN, Akt1, Akt2, mTOR, LKB1 and VEGFA (vascular endothelial growth factor A) in leiomyoma as compared to adjacent normal myometrium. Immunohistochemistry was subsequently performed to analyze expression of PTEN, phospho-Akt, phospho-mTOR, phospho-S6, LKB1 and VEGFA in leiomyoma and adjacent normal myometrium. Results: Significant upregulation of PTEN (2.52 fold; P=0.03) and LKB1 (3.93 fold; P=0.01), and downregulation of VEGFA (2.95 fold; P=0.01) genes were observed in leiomyoma as compared to normal myometrium. Transcript levels of Akt1, Akt2 and mTOR did not vary significantly between leiomyoma and myometrium. An increased immunoexpression of PTEN (P=0.015) and LKB1 (P<0.001) and decreased expression of VEGFA (P=0.01) was observed in leiomyoma as compared to myometrium. Immunostaining for activated (phosphorylated) Akt, mTOR and S6 was absent or low in majority of leiomyoma and myometrium. Interpretation & conclusions: Upregulation of PTEN and LKB1 in concert with negative or low levels of activated Akt, mTOR and S6 indicates that PI3K/Akt/mTOR pathway may not play a significant role in pathogenesis of leiomyoma.
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Affiliation(s)
- Annu Makker
- Post-Graduate Department of Pathology, King George's Medical University, Lucknow, India
| | - Madhu Mati Goel
- Post-Graduate Department of Pathology, King George's Medical University, Lucknow, India
| | - Abbas Ali Mahdi
- Department of Biochemistry, King George's Medical University, Lucknow, India
| | - Vikram Bhatia
- Post-Graduate Department of Pathology, King George's Medical University, Lucknow, India
| | - Vinita Das
- Department of Obstetrics & Gynecology, King George's Medical University, Lucknow, India
| | - Anjoo Agarwal
- Department of Obstetrics & Gynecology, King George's Medical University, Lucknow, India
| | - Amita Pandey
- Department of Obstetrics & Gynecology, King George's Medical University, Lucknow, India
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43
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MARK2 inhibits the growth of HeLa cells through AMPK and reverses epithelial-mesenchymal transition. Oncol Rep 2017; 38:237-244. [PMID: 28560405 DOI: 10.3892/or.2017.5686] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Accepted: 05/03/2017] [Indexed: 11/05/2022] Open
Abstract
Microtubule affinity-regulating kinases (MARKs; MARK1, MARK2, MARK3 and MARK4) act directly downstream of LKB1, the multitasking tumor-suppressor kinase, and thereby mediate its biological effects. Current understanding of the function of MARKs is greatly restricted to regulation of cell polarity. However, whether or how MARKs contribute to cellular growth control remains largely unknown. In the present study, we utilized an inducible lentiviral expression system that allows rapid MARK expression in LKB1-deficient HeLa cells, and characterized additional functions of MARKs: overexpression of MARK2 in HeLa cells resulted in a decrease in cell growth, inhibition of colony formation and arrest in G1 cell cycle phase, with AMPK as the putative downstream effector upregulating the expression of p21 and p16. MARK2 was found to play a role in F-actin reorganization and to contribute to reversal of epithelial‑mesenchymal transition (EMT) as exemplified in the case of HeLa cells that exhibited phenotypic changes, reduced cell migration and invasion. Our findings unveil the coordinated regulation of cell growth and EMT mediated by MARK2, and also provide new insights into the mechanisms underlying the anti-metastatic activity of MARK2.
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44
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Jia C, Medina V, Liu C, He L, Qian D, Taojian T, Okamoto CT, Stiles BL. Crosstalk of LKB1- and PTEN-regulated signals in liver morphogenesis and tumor development. Hepatol Commun 2017; 1:153-167. [PMID: 29152604 PMCID: PMC5687583 DOI: 10.1002/hep4.1027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Liver kinase B 1 (LKB1 or STK11) and phosphatase and tensin homologue deleted on chromosome 10 (PTEN) are two tumor suppressors that regulate the mammalian target of rapamycin signaling pathway. Deletion studies show that loss of either Lkb1 (Lkb+/–) or Pten (PtenloxP/loxP; Alb‐Cre+) leads to liver injury and development of hepatocarcinoma. In this study, we investigated the crosstalk of LKB1 and PTEN loss during tumorigenesis and liver development. We show that haplo‐insufficiency of Lkb1 in the liver leads to advanced tumor development in Pten‐null mice (PtenloxP/loxP; LkbloxP/+; Alb‐Cre+). Our analysis shows that LKB1 and PTEN interact with each other in their regulation of fatty acid synthase as well as p21 expression. The combined loss of LKB1 and PTEN (PtenloxP/loxP; LkbloxP/loxP; Alb‐Cre+) also leads to the inability to form zonal structures in the liver. The lack of metabolic zonal structures is consistent with the inability of the livers to store glycogen as well as elevated plasma bilirubin and alanine aminotransferase, indicative of liver dysfunction. These structural and functional defects are associated with cytoplasm distribution of a canalicular membrane protein multidrug resistant protein 2, which is responsible for clearing bilirubin. This observed regulation of multidrug resistant protein 2 by LKB1 likely contributes to the lack of cellular polarity and the early lethality phenotype associated with the homozygous loss of Lkb1 alone or in combination with Pten. Finally, Pten deletion does not rescue the precocious ductal plate formation reported for Lkb1‐deleted livers. Conclusion: Our study dissected the functional and molecular crosstalk of PTEN and LKB1 and elucidated key molecular targets for such interactions. (Hepatology Communications 2017;1:153‐167)
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Affiliation(s)
- Chengyou Jia
- Department of Nuclear Medicine, Central Laboratory for Medical Research, Shanghai 10th People's Hospital, Tongji University School of Medicine, Shanghai 200072, China.,Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033
| | - Vivian Medina
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033
| | - Chenchang Liu
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033
| | - Lina He
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033
| | - Daohai Qian
- Department of Nuclear Medicine, Central Laboratory for Medical Research, Shanghai 10th People's Hospital, Tongji University School of Medicine, Shanghai 200072, China.,Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033
| | - Tu Taojian
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033
| | - Curtis T Okamoto
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033
| | - Bangyan L Stiles
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033.,Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033
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45
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Deletion of endothelial cell-specific liver kinase B1 increases angiogenesis and tumor growth via vascular endothelial growth factor. Oncogene 2017; 36:4277-4287. [PMID: 28346429 PMCID: PMC5532072 DOI: 10.1038/onc.2017.61] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 01/18/2017] [Accepted: 02/09/2017] [Indexed: 12/25/2022]
Abstract
Liver kinase B1 (LKB1) is a serine/threonine protein kinase ubiquitously expressed in mammalian cells. It was first identified in Peutz-Jeghers syndrome as a tumor suppressor gene. Whether endothelial LKB1 regulates angiogenesis and tumor growth is unknown. In this study, we generated endothelial cell-specific LKB1-knockout (LKB1endo−/−) mice by crossbreeding vascular endothelial-cadherin-Cre mice with LKB1flox/flox mice. Vascular endothelial growth factor (VEGF) level was highly co-stained in endothelial cells but not macrophages in LKB1endo−/− mice. Consistently, LKB1endo−/− mouse tissues including the lung, skin, kidney, and liver showed increased vascular permeability. Tumors implanted in LKB1endo−/− mice but not macrophage-specific LKB1-knockout mice grew faster and showed enhanced vascular permeability and increased angiogenesis as compared with those implanted in wild-type mice. Injection of VEGF-neutralizing antibody but not the isotype-matched control antibody decreased endothelial-cell angiogenesis and tumor growth in vivo. Furthermore, LKB1 deletion enhanced mouse retinal and cell angiogenesis, and knockdown of VEGF by small-interfering RNA decreased endothelial cell proliferation and migration. Re-expression of LKB1 or knockdown of VEGF receptor 2 decreased the over-proliferation and -migration observed in LKB1endo−/− cells. Mechanistically, LKB1 could bind to the VEGF transcription factor, specificity protein 1 (Sp1), which then inhibited the binding of Sp1 to the VEGF promoter to reduce VEGF expression. Endothelial LKB1 may regulate endothelial angiogenesis and tumor growth by modulating Sp1-mediated VEGF expression.
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46
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Le NT, Martin JF, Fujiwara K, Abe JI. Sub-cellular localization specific SUMOylation in the heart. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2041-2055. [PMID: 28130202 DOI: 10.1016/j.bbadis.2017.01.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/21/2016] [Accepted: 01/09/2017] [Indexed: 12/27/2022]
Abstract
Although the majority of SUMO substrates are localized in the nucleus, SUMOylation is not limited to nuclear proteins and can be also detected in extra-nuclear proteins. In this review, we will highlight and discuss how SUMOylation in different cellular compartments regulate biological processes. First, we will discuss the key role of SUMOylation of proteins in the extra-nuclear compartment in cardiomyocytes, which is overwhelmingly cardio-protective. On the other hand, SUMOylation of nuclear proteins is generally detrimental to the cardiac function mainly because of the trans-repressive nature of SUMOylation on many transcription factors. We will also discuss the potential role of SUMOylation in epigenetic regulation. In this review, we will propose a new concept that shuttling of SUMO proteases between the nuclear and extra-nuclear compartments without changing their enzymatic activity regulates the extent of SUMOylation in these compartments and determines the response and fate of cardiomyocytes after cardiac insults. Approaches focused specifically to inhibit this shuttling in cardiomyocytes will be necessary to understand the whole picture of SUMOylation and its pathophysiological consequences in the heart, especially after cardiac insults. This article is part of a Special Issue entitled: Genetic and epigenetic control of heart failure - edited by Jun Ren & Megan Yingmei Zhang.
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Affiliation(s)
- Nhat-Tu Le
- Department of Cardiology - Research, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - James F Martin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Keigi Fujiwara
- Department of Cardiology - Research, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jun-Ichi Abe
- Department of Cardiology - Research, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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47
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Loss of liver kinase B1 causes planar polarity defects in cochlear hair cells in mice. Front Med 2016; 10:481-489. [DOI: 10.1007/s11684-016-0494-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 09/01/2016] [Indexed: 12/11/2022]
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48
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Deletion of Lkb1 in adult mice results in body weight reduction and lethality. Sci Rep 2016; 6:36561. [PMID: 27824128 PMCID: PMC5099919 DOI: 10.1038/srep36561] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 10/18/2016] [Indexed: 12/22/2022] Open
Abstract
Liver kinase B1 (Lkb1) plays crucial roles in development, metabolism and survival. As constitutive knockout of Lkb1 in mice leads to embryonic lethality, whether Lkb1 is required for the growth and survival of adult mice is unclear. Here we address this question using a tamoxifen-inducible Lkb1 knockout (KO) mouse model: Rosa26-CreER: Lkb1flox/flox (abbreviated as Rosa-Lkb1). The Rosa-Lkb1 mice exhibited body weight reduction and died within 6 weeks after tamoxifen induction. The body weight reduction was due to reduced weight of various tissues but the brown and white adipose tissues underwent much more pronounced weight reduction relative to the overall body weight reduction. Accordingly, the Rosa-Lkb1 mice had increased blood glucose levels and were intolerant to glucose challenge. Expression levels of adipogenic and lipogenic genes in adipose tissues were also dramatically reduced by Lkb1 deletion. Additionally, Lkb1 deletion reduced lipid deposition and increased expression of mitochondrial (Pgc1a, Cox5b and Cox7a) and hepatic gluconeogenesis related genes (Pepck) in liver. Finally, the Rosa-Lkb1 mice had much reduced oxygen consumption, carbon dioxide production, and energy expenditure. These results demonstrate that Lkb1 plays an important role in maintaining body weight, liver and adipose tissue function, blood glucose homeostasis and survival in adult mice.
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49
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Creuzet SE, Viallet JP, Ghawitian M, Torch S, Thélu J, Alrajeh M, Radu AG, Bouvard D, Costagliola F, Borgne ML, Buchet-Poyau K, Aznar N, Buschlen S, Hosoya H, Thibert C, Billaud M. LKB1 signaling in cephalic neural crest cells is essential for vertebrate head development. Dev Biol 2016; 418:283-96. [DOI: 10.1016/j.ydbio.2016.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 07/19/2016] [Accepted: 08/06/2016] [Indexed: 11/25/2022]
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50
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Rungsung I, Ramaswamy A. Insights into the structural dynamics of Liver kinase B1 (LKB1) by the binding of STe20 Related Adapterα (STRADα) and Mouse protein 25α (MO25α) co-activators. J Biomol Struct Dyn 2016; 35:1138-1152. [PMID: 27160967 DOI: 10.1080/07391102.2016.1173593] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
LKB1, the tumour suppressor, is found mutated in Peutz-Jeghers syndrome (PJS). The LKB1 is a serine-threonine kinase protein that is allosterically activated by the binding of STRADα and MO25α without phosphorylating the Thr212 present at activation loop. The present study aims to highlight the structural dynamics and complexation mechanism during the allosteric activation of LKB1 by these co-activators using molecular dynamics simulations. The all atom simulations performed on the complexes of LKB1 with ATP, STRADα, and MO25α for a period of 30 ns reveal that binding of STRADα and MO25α significantly stabilizes the highly flexible regions of LKB1 such as ATP binding region (β1-β2 loop), catalytic & activation loop segments and αG helix. Also, binding of STRADα and MO25α to LKB1 promotes coordinated motion between N- and C-lobes along with the catalytic & activation loops by forming H-bonds between LKB1 and co-activators, which further facilitate to establish the conserved attributes of active LKB1 such as (i) formation of salt bridge between Lys78 and Glu98, (ii) formation of stable hydrophobic R- and C-spines, and (iii) interaction between both catalytic and activation loops. Especially, the residues of LKB1 interacting with STRADα (Arg74, Glu342) and MO25α (Glu165, Pro203 and Phe204) are observed to play a significant role in stabilizing the (LKB1-ATP)-(STRADα-ATP)-MO25α complex. Overall, the present work highlighting the structural dynamics of LKB1 by the binding of allosteric co-activators is expected to provide a basic understanding on drug design specific to PJS syndrome.
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Affiliation(s)
- Ikrormi Rungsung
- a Centre for Bioinformatics, School of Life Sciences , Pondicherry University , Puducherry 605014 , India
| | - Amutha Ramaswamy
- a Centre for Bioinformatics, School of Life Sciences , Pondicherry University , Puducherry 605014 , India
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